Micro II Quiz 9, 10, 11, 12
If not inoculated immediately, viral specimens should be stored in viral transport media for up to 48 hours. What is the correct storage temperature (° C)? 0 to 4 35-37 22-25 42 30
0 to 4
The definitive diagnosis of viral infections using serological methods involves the demonstration of a _?_ between acute and convalescent specimens. 4 fold rise in titer decreasing titer Single elevated titer negative titer Constant low titer
4 fold rise in titer
Which of the following is evidence of acute rubella virus infection (german measles)? 1/8 >1/64 1/16 4-fold rise in titer (acute/convalescent sera) 1/32
4-fold rise in titer (acute/convalescent sera)
Proper collection of a sample for recovery of Enterobius vermicularis includes collecting: A 24-hour urine collection A first morning stool collection with proper preservative A scotch tape preparation from the perianal region Peripheral blood from a finger
A scotch tape preparation from the perianal region
The causative agents of lumby jaw are: Clostridiumspp Bacteroides spp Prevotella spp Actinomycesspp
Actinomycesspp
An oxidase positive, gram negative rod isolated from a stool culture has the following biochemical characteristics: lactose fermentation = negative sucrose fermentation = positive DNase production = positive gelatin hydrolysis = positive no growth in 3% NaCl ornithine decarboxylase = positive lysine decarboxylase = negativearginine dihydrolase = positive This organism is most likely Aeromonas hydrophila Vibrio parahaemolyticus Vibrio cholera Pseudomonas aeruginosa Plesiomonas shigelloides
Aeromonas hydrophila
Which of the following is the causative agent of bartholinitis? Neisseria gonorrhoeae Anaerobic and polymicrobic infections originating from normal genital flora E. coli and other enteric organisms
Anaerobic and polymicrobic infections originating from normal genital flora
A parasite found in the Far East is commonly known as the rat lungworm. In humans, ingestion of raw slugs, snails, or prawns leads to a benign meningitis characterized by eosinophilia of the blood and cerebrospinal fluid. What is the genus-species name of this parasite? Angiostrongylus cantonensis Dracunculus medinensis Angiostrongylus costaricensis Gnathostoma spinigerum Dirofilaria immitis
Angiostrongylus cantonensis
Which parasite causes eosinophilic meningoencephalitis, a form of larva migrans causing fever, headache, stiff neck, and increased cells in the spinal fluid? Necator americanus Angiostrongylus cantonensis Ancylostoma braziliense Strongyloides stercoralis
Angiostrongylus cantonensis
A young child, whose family has recently emigrated from Brazil, exhibits the following symptoms: severe abdominal pain, fever, anorexia, and vomiting. He is seen by a physician who discovers a large mass within the colo‑rectal area during his physical examination of the patient. This large mass is confirmed by radiographic evidence (X-rays). Following surgical resection to remove the mass, a worm-like organism is found within the tissue by the pathologist. Considering the country of origin, the symptoms, and the lab findings, this organism is most likely - Angiostrongylus cantonensis Dracunculus medinensis Angiostrongylus costaricensis Trichinella spiralis Dirofilaria immitis
Angiostrongylus costaricensis
What adult nematode can grow to lengths of 25 to 30 cm in length, have a width approximately that of a pencil, and is capable of causing intestinal obstruction or piercing the bowel wall causing peritonitis and possibly death? Ascaris lumbricoides Necator americanus Ancylostoma duodenale Trichuris trichiura Enterobius vermicularis
Ascaris lumbricoides
A stool specimen that was still warm from body heat is received in the parasitology section of the laboratory. The direct wet mount is performed immediately and motile organisms are clearly seen with the low power objective. The parasitic forms have the following microscopic morphology: number of nuclei = 2 a large cytostome is present a kidney-bean or horseshoe shaped macronucleus numerous cilia cover the parasite a small, round micronucleus which is not visible directional motility
Balantidium coli
Actively motile parasites are seen in a saline direct wet mount. The organisms possess the following characteristics: small round micronucleus large kidney-bean or horseshoe shaped macronucleus large, funnel-shaped cytostome numerous cilia providing directional motility 2 size ranges: 42-62 and 90-120 This organism is most likely Entamoeba histolytica Balantidium coli Entamoeba coli Dientamoeba fragilis Giardia duodenalis
Balantidium coli
What is the only ciliate which parasitizes man? Giardia duodenalis Balantidium coli Dientamoeba fragilis Chilomastix mesnili Pentrarichomonas hominis
Balantidium coli
Penicillin resistance in Neisseria gonorrhoeae can be due to the organism producing: Beta-D-galactosidase Beta-lactamase Butyrate esterase DNase
Beta-lactamase
The appearance of the classic erythema migrans lesion is associated with which of the following? Leptospira interrogans Borrelia burgdorferi Treponema carateum Rickettsia rickettsia
Borrelia burgdorferi
What is the name of the inactive stage of Toxoplasma gondii, which may cause reactivation of toxoplasmosis in immunocompromised patients (AIDS, transplant, leukemia and lymphoma patients, etc). This is the quiescent or dormant stage which encysts in the tissues of infected hosts (small mammals, cattle, chicken, humans, etc).
Bradyzoites
A 36-year-old man who has been traveling through the orient is experiencing a tender region in the inguinal region. A blood film is made, and sheathed microfilariae with four to five subterminal nuclei and two terminal nuclei in the tail are identified using Giemsa stain. The organism is most likely: Wuchereria bancrofti Onchocerca volvulus Loa loa Brugia malayi
Brugia malayi
Examination of a peripheral blood smear reveals the presence of microfilariae with the following characteristics: a size range of 175-230 microns (µm) the presence of a sheath nuclei extending into the tip of the tail 2 terminal nuclei are distinctly separate from the other caudal nuclei The parasitic organism which produces microfilariae that fit this description is - Brugia malayi Onchocerca volvulus Wuchereria bancrofti Loa loa
Brugia malayi
? , which inhabits the hair follicles and sebaceous glands, does not cause a serious parasitic disease but has been associated with acne, comedones (blackheads), and keratitis. Sarcoptes scabiei (scabies mite) Pediculus humanus humanus(body louse) Eutrombicula sp. (trombiculid mites) Pediculus humanus capitis(head louse) Demodex folliculorum (hair follicle mite)
Demodex folliculorum (hair follicle mite)
Trophozoite forms which appeared to be amoeboid are seen on a trichrome-stained stool smear. The organisms seen have the following morphologic characteristics: number of nuclei = 1 or 2 (60%) numerous vacuoles in the cytoplasm no peripheral chromatin ingested bacteria, yeast, and organic debris karyosome is "fragmented" size range = 7-12 µm
Dientamoeba fragilis
Infection by this organism can cause B12 deficiency:
Dipyllobothrium latum
The heartworm of dogs and cats is known as - Dirofilaria immitis Gnathostoma spinigerum Trichinella spiralis Onchocerca volvulus Dracunculus medinensis
Dirofilaria immitis
Proper design of a urogenital swab expressly intended for the collection of urethral discharge should include what feature? Charcoal-treated cotton or rayon Antibiotic-treated calcium alginate Non flexible Shaft of wood and not flexible Dacron-tipped swabs
Charcoal-treated cotton or rayon
Examination of a saline direct wet mount of a fresh stool specimen reveals the presence of mononuclear organisms with the following characteristics: 3 anterior flagella and a spiral groove which appears to run around the body Cytostomal fibrils in the shape of a "shepherd's crook" surround the cytostome The size range is 10-20 microns
Chilomastix mesnili
Which of the following is the causative agent of nongonococcal urethritis? mumps virus Chlamydia trachomatis Gardnerella, Prevotella spp, Porphyromonas spp, Peptostreptococcus spp, Mobiluncus spp N. gonorrhoeae and C. trachomatis
Chlamydia trachomatis
Profuse watery diarrhea (i.e., "rice water stools"), leading to dramatic fluid loss, severe dehydration, and hypotension that frequently leads to death, is the hallmark of which toxin activity? Cholera toxin (CT) Enteric endotoxin Shiga toxin Toxin A
Cholera toxin (CT)
Which of the following defines progressive bacterial synergistic gangrene? Slowly progressive infection of the subcutaneous tissue with associated ulceration of portions of the overlying skin Infection of the fascia overlying muscle groups, often with the involvement of the overlying soft tissue Chronic gangrenous condition of the skin most often encountered as a postoperative complication, particularly after abdominal or thoracic surgery Extensive necrosis of muscle caused by infectious agents
Chronic gangrenous condition of the skin most often encountered as a postoperative complication, particularly after abdominal or thoracic surgery
Ingestion of infected copepods may lead to a disease in which the adult worms migrate through deep connective tissue. The disease is usually asymptomatic until the female appears in the subcutaneous tissue where she lies just under the skin. A papule and vesicle appear and eventually an ulcer develops. Larvae are discharged when the ulcer is immersed in water. This parasite is called -
Dracunculus medinensis
Which of the following defines acute urethral syndrome? Inflammation of the kidney parenchyma, calices (cup-shaped division of the renal pelvis), and pelvis Infection of the terminal portion of the lower urinary tract Dysuria frequency, and urgency, but a specimen yielding fewer organisms than 105CFU/mL urine culture Infection of the bladder Isolation of a specified quantitative count of bacteria in an appropriately collected urine specimen obtained from a person without symptoms or signs of urinary infection
Dysuria frequency, and urgency, but a specimen yielding fewer organisms than 105CFU/mL urine culture
The most frequent cause of uncomplicated community-acquired urinary tract infections in: S. saprophyticus Klebisella spp. E. coli Proteus
E. coli
Which of the following is the causative agent of prostatitis? Neisseria gonorrhoeae Anaerobic and polymicrobic infections originating from normal genital flora E. coli and other enteric organisms
E. coli and other enteric organisms
Human feces is not a recommended specimen in the detection of:
Echinococcus granulosus
Hydatid cysts are the diagnostic stage for: Hymenolepis nana Taenia solium Echinococcus granulosus Hymenolepis diminuta Taenia saginata
Echinococcus granulosus
Examination of a trichrome stained smear from a stool specimen revealed the presence of many mononuclear organisms with the following morphological characteristics: numerous vacuoles in the cytoplasm inclusions = bacteria, yeast and organic debris Size range: 5-12 µm (avg. size is approximately 7 µm)peripheral chromatin= none karyosome = large, irregularly shaped the nuclear membrane appears as a thin, delicate line The protozoan parasite isolated in this stool specimen is most likely - Endolimax nana Entamoeba hartmanni Iodamoeba butschlii Entamoeba coli Dientamoeba fragilis
Endolimax nana
Examination of a trichrome stained smear from a stool specimen revealed the presence of many mononuclear organisms with the following morphologic characteristics: numerous vacuoles in the cytoplasm peripheral chromatin is unevenly distributed karyosome is large, irregularly shaped & eccentricbacteria, yeast and organic debris in the cytoplasm coarsely granular cytoplasm (no hyaline ectoplasm) size range is 15-50 µm (microns) This protozoan parasite is most likely - Entamoeba polecki Entamoeba dispar Entamoeba coli Entamoeba histolytica Entamoeba hartmanni
Entamoeba coli
A loose, watery stool with blood and mucus is received. A fecal smear is prepared and stained with Trichrome staining reagents. When examined with the oil immersion lens, trophic forms with the following morphologic features are seen: number of nuclei = 1 finely granular endoplasm and hyaline ectoplasm small, round, centrally-located karyosome inclusions: ingested red blood cells evenly distributed peripheral chromatin size range = 12-60 microns (µm)
Entamoeba histolytica
Examination of a stained stool smear revealed amoebae with the following characteristics: finely granular endoplasm with hyaline (clear) ectoplasm peripheral chromatin is evenly distributed and the karyosome is small, round, and centrally located cytoplasmic inclusions include ingested red blood cells size range is 12 to 60 microns This protozoan parasite seen in both the saline and iodine DWM is most likely? Entamoeba histolytica Entamoeba polecki Entamoeba coli Entamoeba dispar Entamoeba hartmanni
Entamoeba histolytica
A stool specimen was sent to the laboratory to be examined for helminth ova (eggs) and protozoa parasites (O & P). No parasites were seen on the direct wet mount (saline or iodine) but spherical objects were seen in the sediment from the concentration procedure. The same organisms were seen on the trichrome-stained fecal smear. The organisms had the following morphological characteristics: number of nuclei = 1 to 4 elongate chromatin bodies with rounded ends small, round, centrally-located karyosome hyaline cyst wall and fine granular cytoplasm evenly distributed peripheral chromatin size range = 10-20 microns (µm) These objects are most likely- Entamoeba coli cysts Iodamoeba butschlii Entamoeba hartmanni cysts Giardia lamblia cysts Entamoeba histolytica/disparcysts
Entamoeba histolytica/disparcysts
The most common etiologic agent in uncomplicated community-acquired urinary tract infection is: Escherichia coli Klebsiella spp. Staphylococcus saprophyticus Streptococcus pyogenes
Escherichia coli
The six‑legged larvae of ? are ectoparasites of vertebrates, but the eight‑legged larvae and adults parasitize other arthropods. In human infestation, the larvae feed on tissue juices. The saliva produces an intense pruritis (itching) and a severe dermatitis. Sarcoptes scabiei (scabies mite) Pediculus humanus humanus(body louse) Eutrombicula sp. (chiggers) Pediculus humanus capitis(head louse) Demodex folliculorum (hair follicle mite)
Eutrombicula sp. (chiggers)
Which of the following defines myositis? Slowly progressive infection of the subcutaneous tissue with associated ulceration of portions of the overlying skin Infection of the fascia overlying muscle groups, often with the involvement of the overlying soft tissue Chronic gangrenous condition of the skin most often encountered as a postoperative complication, particularly after abdominal or thoracic surgery Extensive necrosis of muscle caused by infectious agents
Extensive necrosis of muscle caused by infectious agents.
The adults of ? are leaf shaped with an anteriorly located "cephalic cone".
Fasciola hepatica
The adults of ? are leaf shaped with an anteriorly located "cephalic cone". Fasciola hepatica Heterophyes heterophyes Fasciolopsis buski Paragonimus westermani
Fasciola hepatica
The infective stage for the agents of filariasis (the microfilariae) are - Metacercariae Sporozoites Cercariae Embryonated eggs Filariform larvae (3rd stage)
Filariform larvae (3rd stage)
The painful stings of ? result in flares and wheals up to an inch or more in diameter. Fire ants Tunga penetrans (chigoe fleas) Dermacentor andersoni (wood tick) Oestrus ovis (sheep botflies) Demodex folliculorum (hair follicle mite)
Fire ants
The Heterophyes heterophyes worm, which has a genital sucker that surrounds the genital pore, has a variety of reservoir hosts including dogs, casts, and birds and a second intermediate host of freshwater: Snails Fish Crabs Shrimp
Fish
Which of the following provides the first serologic evidence (marker) of hepatitis B virus (HBV) infection? HBsAg anti-HBc HBcAg anti-HBs HBeAg
HBsAg
The most frequent clinical signs of chronic Chagas disease involve the enlargement of which organ? Heart Liver Spleen Lung
Heart
The porphyrin test was devised to detect strains of Haemophilus capable of: Ampillicin degradation Capsule production Hemin synthesis Chloramphenicol resistance
Hemin synthesis
A stool specimen was submitted for examination to rule out the presence of gastrointestinal parasites. Both the DWM and the formalin-ether concentration procedure revealed helminth eggs with the following characteristics - a size range: 55-75 µm an ovoid shapean extremely thin shell larval development in the early cleavage stage What parasite produces eggs of this description?
Human hookworms
The definitive host for Wuchereria bancrofti is: Mosquito Microfilaria Humans Tabanid fly
Humans
A definitive diagnosis can be made in a Trichinella spiralis infection on the basis of which of the following findings? Presence of adult worms in the feces Identification of encysted larvae through muscle biopsy Presence of cutaneous larvae migrans in the skin Identification of unembryonated eggs in the feces
Identification of encysted larvae through muscle biopsy
The term which refers to the sexually mature, adult arthropod is - Pupa Nymph Larva Imago Nit
Imago
Proper storage of cerebrospinal fluid (CSF) sent to the laboratory for bacterial culture includes:
Incubation at 35°C.
Which of the following defines cystitis? Inflammation of the kidney parenchyma, calices (cup-shaped division of the renal pelvis), and pelvis Infection of the terminal portion of the lower urinary tract Dysuria frequency, and urgency, but a specimen yielding fewer organisms than 105CFU/mL urine culture Infection of the bladder Isolation of a specified quantitative count of bacteria in an appropriately collected urine specimen obtained from a person without symptoms or signs of urinary infection
Infection of the bladder
Which of the following defines necrotizing fasciitis? Slowly progressive infection of the subcutaneous tissue with associated ulceration of portions of the overlying skin Infection of the fascia overlying muscle groups, often with the involvement of the overlying soft tissue Chronic gangrenous condition of the skin most often encountered as a postoperative complication, particularly after abdominal or thoracic surgery Extensive necrosis of muscle caused by infectious agents
Infection of the fascia overlying muscle groups, often with the involvement of the overlying soft tissue
Which of the following defines urethritis? Inflammation of the kidney parenchyma, calices (cup-shaped division of the renal pelvis), and pelvis Infection of the terminal portion of the lower urinary tract Dysuria frequency, and urgency, but a specimen yielding fewer organisms than 105CFU/mL urine culture Infection of the bladder Isolation of a specified quantitative count of bacteria in an appropriately collected urine specimen obtained from a pe
Infection of the terminal portion of the lower urinary tract
Which of the following defines chorioamnionitis? Polymicrobial type of vaginitis characterized by mild perivaginal irritation and a foul-smelling discharge Infection of the uterus and its contents during pregnancy Inflammation of the vaginal mucosa resulting in an abnormal discharge and offensive odor or itching Mild-to-severe inflammation of the testicles that is generally acquired by blood-borne dissemination of viruses such as the mumps virus
Infection of the uterus and its contents during pregnancy
Which of the following defines pyelonephritis? Inflammation of the kidney parenchyma, calices (cup-shaped division of the renal pelvis), and pelvis Infection of the terminal portion of the lower urinary tract Dysuria frequency, and urgency, but a specimen yielding fewer organisms than 105CFU/mL urine culture Infection of the bladder Isolation of a specified quantitative count of bacteria in an appropriately collected urine speci
Inflammation of the kidney parenchyma, calices (cup-shaped division of the renal pelvis), and pelvis
Which of the following defines vaginitis? Polymicrobial type of vaginitis characterized by mild perivaginal irritation and a foul-smelling discharge Infection of the uterus and its contents during pregnancy Inflammation of the vaginal mucosa resulting in an abnormal discharge and offensive odor or itching Mild-to-severe inflammation of the testicles that is generally acquired by blood-borne dissemination of viruses such as the mumps virus
Inflammation of the vaginal mucosa resulting in an abnormal discharge and offensive odor or itching.
Infection with Taenia saginata is transmitted through - Skin penetration by filariform larvae Ingestion of cysticercus larvae in pork Ingestion of cysticercus larvae in beef Skin penetration by rhabditiform larvae Ingestion of plerocercoid larvae
Ingestion of cysticercus larvae in beef
Humans and animals which harbor the developmental stages of a parasite (larval forms) or hosts in which asexual reproduction alone occurs are called- Reservoir hosts Intermediate hosts Accidental hosts Definitive hosts Incidental hosts
Intermediate hosts
Examination of a saline direct wet mount of a fresh stool specimen reveals the presence of mononuclear organisms with the following characteristics: numerous vacuoles in the cytoplasm containing bacteria, yeast, and organic debris no peripheral chromatin is seen and the karyosome is large and irregularly shaped the karyolymph space appears "dirty" due to the presence of chromatin granules the size range is 4 to 20µm (average size = 9-12 µm) The organism seen in this wet mount preparation is most likely - Entamoeba histolytica Iodamoeba butschlii Entamoeba coli Chilomastix mesnili Endolimax nana
Iodamoeba butschlii
Examination of a trichrome stained smear from a preserved stool specimen reveals the presence of numerous cysts with the following characteristics: Single nucleus with a large, irregularly shaped karysome There is no peripheral chromatin. A large glycogen vacuole is present The karyolymph space contains chromatin granules in the shape of a crescent creating a "flower basket" nucleus. The size range is 9 to 11 microns. What is the identity of this parasite? Entamoeba polecki Naegleria fowler Endolimax nana Entamoeba coli Iodamoeba butschlii
Iodamoeba butschlii
Which of the following defines asymptomatic bacteriuria?
Isolation of a specified quantitative count of bacteria in an appropriately collected urine specimen obtained from a person without symptoms or signs of urinary infection.
Which of the following is the vector for Leishmania mexicana? Rhodnius / Triatoma / Panstrongylus (Reduviid or Kissing bugs) Lutzomyia (sandflies) Glossina (Tsetse flies) Simulium (Black fly / buffalo gnat)
Lutzomyia (sandflies)
If a Wood's lamp examination of skin lesions reveals a golden-yellow fluorescence, then what superficial mycoses are expected? Malassezia furfur Trichosporon spp Candida albicans Cryptococcus neoformans
Malassezia furfur
A peripheral blood smear is examined revealing the presence of microfilariae with the following characteristics: an average size of 93 µm no sheath is present nuclei extent into the tip of the tail. A pair of terminal nuclei is slightly separated from the other caudal nuclei The parasitic organism which produces microfilaria that fit this description is - Brugia malayi Mansonella streptocerca Mansonella perstans Mansonella ozzardi
Mansonella perstans
What term is used to describe the transmission of infective organisms from feces or contaminated soil to food by the feet or mouth parts of insects? No development or growth of the parasite occurs in the insect. Mechanical transfer Metamorphosis Transovarial transmission Biological transmission Biological vectors
Mechanical transfer
Asexual reproduction of malarial parasites in the liver and in red blood cells results in the production of ? which are found within schizonts. Tachyzoites Sporozoites Hypnozoites Bradyzoites Merozoites
Merozoites
In arthropods, maturation from one developmental stage to another is called -
Metamorphosis
Which of the following defines orchitis? Polymicrobial type of vaginitis characterized by mild perivaginal irritation and a foul-smelling discharge Infection of the uterus and its contents during pregnancy Inflammation of the vaginal mucosa resulting in an abnormal discharge and offensive odor or itching Mild-to-severe inflammation of the testicles that is generally acquired by blood-borne dissemination of viruses such as the mumps virus
Mild-to-severe inflammation of the testicles that is generally acquired by blood-borne dissemination of viruses such as the mumps virus
Which of the following is a test for immunity to visceral leishmaniasis? It is negative during active disease but positive after recovery Mantoux skin test Montenegro skin test Sporotrichin skin test tuberculin skin test
Montenegro skin test
Which of the following is the causative agent of epididymitis? mumps virus Chlamydia trachomatis Gardnerella, Prevotella spp, Porphyromonas spp, Peptostreptococcus spp, Mobiluncus spp N. gonorrhoeae and C. trachomatis
N. gonorrhoeae and C. trachomatis
The etiologic (causative) agent of primary amoebic meningoencephalitis (PAM), a rapidly progressive, invariably fatal disease whose entire course seldom exceeds 3-7 days is - Entamoeba histolytica Acanthamoeba astronyxis Naegleria fowleri Endolimax nana Acanthamoeba castellani
Naegleria fowleri
Which of the following is the causative agent of cervicitis? Neisseria gonorrhoeae Anaerobic and polymicrobic infections originating from normal genital flora E. coli and other enteric organisms
Neisseria gonorrhoeae
A braching Gram-positive, partially acid-fast organism is isolated from a bronchial washing on a 63-year-old woman receiving chemotherapy. The organism does not hydrolyze casein, tyrosine, or xanthine. The most likely genus causing the infection is: Actinomadura Erysepelothrix Nocardia Streptomyces
Nocardia
A fibrous skin nodule is removed from the back of a patient from Central America. A microfilaria seen upon microscopic exam of the nodule is most likely: Wuchereria bancrofti Brugia malayi Onchocerca volvulus Loa loa
Onchocerca volvulus
Which microfilariae are usually not found circulating in the peripheral blood? Brugia malayi Wuchereria bancrofti Onchocerca volvulus Loa loa
Onchocerca volvulus
Which species of blood and tissue nematode produces microfilariae found in the subcutaneous tissues having the following characteristics: a size range of 150 to over 350 microns (µm) no sheath is presentnuclei do not extend into the tip of the tail (the tail is free of nuclei) The parasitic organism which produces microfilariae that fit this description is -
Onchocerca volvulus
An infection that results when cervical microorganisms travel upward to the endometrium, fallopian tubes, and other pelvic structures and produce inflammatory conditions such as endometritis, salpingitis, peritonitis, or abscesses is: chorioamnionitis bartholinitis cervicitis PID
PID
Small, glistening, white objects are observed in the scalp hairs of a child. Actively motile adult forms, which are dorso-ventrally flattened, are also seen crawling among the hair shafts. What is the name of this ectoparasite?
Pediculus humanus capitis(head louse)
Small, glistening, white objects are observed in the scalp hairs of a child. Actively motile adult forms, which are dorso-ventrally flattened, are also seen crawling among the hair shafts. What is the name of this ectoparasite? Sarcoptes scabiei (scabies mite) Pediculus humanus humanus(body louse) Eutrombicula sp. (trombiculid mites) Pediculus humanus capitis(head louse) Demodex folliculorum (hair follicle mite)
Pediculus humanus capitis(head louse)
Mycoplasmas are organisms without cell walls. Which antimicrobial agents would be ineffective in treating infections involving this bacterium? Tetracycline Aminoglycosides Penicillin Rifampin
Penicillin
A stained stool smear reveals the presence of a mononuclear organism with the following characteristics: An anteriorly located nucleus 4 flagella and an undulating membrane costa and undulating membrane run the length of bodyjerky, non-directional motility The size range is 7 to 15 µm The intestinal protozoan described above is most likely - Giardia duodenalis Pentatrichomonas hominis Chilomastix mesnili Trichomonas vaginalis Dientamoeba fragilis
Pentatrichomonas hominis
Which of the following is the vector for Leishmania tropica? Rhodnius / Triatoma / Panstrongylus (Reduviid or Kissing bugs) Phlebotomus (sandflies) Glossina (Tsetse flies) Simulium (Black fly / buffalo gnat)
Phlebotomus (sandflies)
Examination of a peripheral blood smear revealed the presence of malarial parasites. Only ring forms, many with double chromatin dots, were seen on the peripheral blood smear. In many cases red cells contained multiple malarial parasites. Other characteristics included - sausage (banana) shaped gametocytes no Schüffner's dots a fever cycle of 36-48 hours schizonts: 8-36 merozoites (average of 24) This organism is most likely - Plasmodium vivax Plasmodium falciparum Plasmodium malariae Plasmodium ovale
Plasmodium falciparum
The causative agent of cerebral malaria and black water fever is - Plasmodium vivax Plasmodium falciparum Plasmodium malariae Plasmodium ovale
Plasmodium falciparum
This parasite has the following characteristics:Banana shaped gametocytes in RBCsMultiple ring forms in RBCsAll RBCs are infected The identification of the parasite is: Plasmodium falciparum Plasmodium malariae Plasmodium ovale Plasmodium vivax
Plasmodium falciparum
Examination of a peripheral blood smear revealed the presence of trophic forms and schizonts within a patient's RBCs. Infected RBCs appeared to be pale and larger than normal. Maturing trophozoites were highly motile, exhibiting bizarre shapes when stained. Other characteristics of this malarial parasitic forms were noted - ring forms with a single chromatin dot Schüffner's dots are presenta fever cycle of 48 hours schizonts with 12-24 merozoites (average of 16) This organism is most likely - Plasmodium vivax Plasmodium falciparum Plasmodium malariae Plasmodium ovale
Plasmodium vivax
Malarial parasites are seen on a peripheral blood smear. Infected red cells appear to be pale and larger than normal, oval shaped, and have ragged margins. Other characteristics include - Schüffner's dots are present ring forms with a single chromatin dot a fever cycle of 48 hours schizonts with an average of 8 merozoites What is the name of this parasite? Plasmodium vivax Plasmodium falciparum Plasmodium malariae Plasmoidum ovale
Plasmoidum ovale
Which of the following defines bacterial vaginosis? Polymicrobial type of vaginitis characterized by mild perivaginal irritation and a foul-smelling discharge Infection of the uterus and its contents during pregnancy Inflammation of the vaginal mucosa resulting in an abnormal discharge and offensive odor or itching Mild-to-severe inflammation of the testicles that is generally acquired by blood-borne dissemination of viruses such as the mumps virus
Polymicrobial type of vaginitis characterized by mild perivaginal irritation and a foul-smelling discharge
The influenza B virus usually causes a mild upper respiratory disease in children. Administration of salicylates (such as aspirin) to relieve the flu-like symptoms, may lead to a life threatening condition known as - pharyngitis (sore throat) viremia orchitis Reye's syndrome conjunctivitis
Reye's syndrome
Which of the following is the vector for Trypanosoma cruzi? Rhodnius / Triatoma / Panstrongylus (Reduviid or Kissing bugs) Lutzomyia (sandflies) Glossina (Tsetse flies) Simulium (Black fly / buffalo gnat)
Rhodnius / Triatoma / Panstrongylus (Reduviid or Kissing bugs)
Which of the following is the vector for Trypanosoma rangeli?
Rhodnius / Triatoma / Panstrongylus (Reduviid or Kissing bugs)
An organism that many women carry as part of their normal genital microbial flora that may be transmitted to the neonate during childbirth is: Staphylococcus Escherichia coli S. agalactiae G. vaginalis
S. agalactiae
Which of the following is an important cause of neonatal sepsis (as a result of colonization of the vaginal tract of pregnant women)? Streptococcus pyogenes (group A) S. agalactiae (group B) S. pneumonia Enterococcus faecalis viridans streptococci
S. agalactiae (group B)
The causative agent of mange (animals) and scabies (man) is - Pediculus humanus humanus Sarcoptes scabiei Pediculus humanus corporis Demodex folliculorum Pthirus pubis
Sarcoptes scabiei
Examination of a stool specimen reveals the presence of an egg with the following characteristics: embryonated size range of 55-85 µm ovoid to spherical shapethin shell yellowish brown color no lateral or terminal spine
Schistosoma japonicum
A large lateral spine is characteristic of which Schistosoma egg? Schistosoma mansoni Schistosoma japonicum Schistosoma haematobium Schistosoma mekongi
Schistosoma mansoni
Examination of a stool specimen reveals eggs with the following characteristics: embryonated an elongated, ovoid shape size range of 114-180 µm thin shell yellowish brown color large lateral spine The parasite which produces eggs of this description is - Schistosoma mansoni Schistosoma japonicum Schistosoma haemotobium Fasciola / Fasciolopsis
Schistosoma mansoni
Which of the following trematodes is dioecious (separate males & females)? The male is incurved to form the gynecophoral canal. Fasciola hepatica (sheep liver fluke) Schistosoma species (blood flukes) Fasciolopsis buski (giant intestinal fluke) Paragonimus westermani (lung fluke)
Schistosoma species (blood flukes)
What is the principal means of distinguishing Entamoeba histolytica from Entamoeba hartmanni by light microscopy? Size of the trophozoite Appearance of karyosome Appearance of nuclear chomatin Number of nuclei in cyst form
Size of the trophozoite
Which of the following defines meleney ulcer? Slowly progressive infection of the subcutaneous tissue with associated ulceration of portions of the overlying skin Infection of the fascia overlying muscle groups, often with the involvement of the overlying soft tissue Chronic gangrenous condition of the skin most often encountered as a postoperative complication, particularly after abdominal or thoracic surgery Extensive necrosis of muscle caused by infectious agents
Slowly progressive infection of the subcutaneous tissue with associated ulceration of portions of the overlying skin.
The first intermediate host of the Schistosomes is freshwater: Fish Snails Crabs Crayfish
Snails
The infective stage for Isospora belli is the mature oöcyst containing 2 sporocysts each containing 4 -
Sporozoites
Folliculitis, furuncles, and carbuncles are localized abscesses either in or around hair follicles. Which organism is the most common etiologic agent for all three infections? Pseudomonas aeruginosa Staphylococcus epidermidis Escherichia coli Staphylococcus aureus
Staphylococcus aureus
A 36-year-old man enters the emergency department with lesions that are painful, red, swollen, and indurated. He is febrile and exhibiting regional lymphadenopathy (swollen glands). The lesions are marked and well demarcated with a raised border. Which organism is most likely responsible for causing this infection? Streptococcus pyogenes P. aeruginosa Microsporum spp Bacteroides fragilis group
Streptococcus pyogenes
Which of the following statements is true regarding onchocerciasis? The adult worm is present in the blood The microfilariae are in the blood during the late evening hours The diagnostic test of choice is the skin snip The parasite resides in the deep lymphatics
The diagnostic test of choice is the skin snip
Vibrio parahaemolyticus is best isolated from feces on: Eosin methylene blue (EMB) agar Hektoen enteric (HE) agar Salmonella Shigella (SS) agar Thiosulfate citrate bile salts (TCBS) agar
Thiosulfate citrate bile salts (TCBS) agar
Dermacentor andersoni (the wood tick) is associated with tick paralysis caused by - Loss of blood Trypanosomes in the blood Anaphylaxis (allergic reaction) Transmission of microfilaria Toxins in the saliva
Toxins in the saliva
Visceral larva migrans is associated with which of the following organisms?
Toxocara
? is the cause of visceral larval migrans. First stage larvae, unable to develop into adults, migrate through the tissues and develop into second stage larvae. Development to the adult stage (mating, and the production of eggs) can only be completed in puppies less than 5 weeks of age.
Toxocara canis/cati(non-human ascarids)
? is the cause of visceral larval migrans. First stage larvae, unable to develop into adults, migrate through the tissues and develop into second stage larvae. Development to the adult stage (mating, and the production of eggs) can only be completed in puppies less than 5 weeks of age. Dirofilaria immitis Dipylidium caninum Gnathostoma spinigerum Toxocara canis/cati(non-human ascarids) Dracunculus medinensis
Toxocara canis/cati(non-human ascarids)
Motile organisms are seen in a young female's urine specimen. This organism has an undulating membrane and costa that run down ½ the length of the body, there are four anterior flagella, and an axostyle extending from the posterior end. The characteristic motility is jerky and non-directional. This organism is most likely- Giardia duodenalis Pentatrichomonas hominis Dientamoeba fragilis Balantidium coli Trichomonas vaginalis
Trichomonas vaginalis
Examination of a direct wet mount revealed the presence of helminth eggs with the following characteristics - a size range of 75-95 µm an ovoid shapean extremely thin shell with somewhat pointed ends larval development in the early cleavage stage What parasite produces eggs of this description? Trichuris trichiura human hookworms Trichostrongylus species Ascaris lumbricoides Enterobius vermicularis
Trichostrongylus species
Winterbottom's sign, enlargement of the posterior cervical lymph nodes, is characteristic for - Trypanosoma cruzi Trypanosoma brucei rhodesiense Trypanosoma rangeli Trypanosoma brucei gambiense
Trypanosoma brucei gambiense
A patient, with a history of travel to East Africa has been admitted into the hospital with a febrile illness. When a peripheral blood smear is examined, parasitic forms with the following characteristics are observed: pleomorphic, fusiform shapes, some are short (15 μm), broad, and lack a free flagellum. Some are long (up to 30 μm) and slender with a flagellum exiting the anterior end. In both forms the nucleus is centrally located, a small round kinetoplast is located posteriorly and an undulating membrane runs the length of the body. This organism is most likely: Trypanosoma cruzi (American trypanosomiasis) Trypanosoma brucei gambiensi Trypanosoma rangeli(non-pathogen) Trypanosoma brucei rhodesiensi
Trypanosoma brucei rhodesiensi
What hemoflagellate is associated with Romana's sign (inflammation & edema of the face with marked edema of the eyelids)? Trypanosoma cruzi Trypanosoma rhodesiense Trypanosoma rangeli Trypanosoma gambiense
Trypanosoma cruzi
Xenodiagnosis, which requires the use of laboratory bred, trypanosome-free reduviid (kissing) bugs, can be used to diagnose infection caused by ? . This method is useful in chronic cases seen in older children and adults where the number of trypanosomes may be low in number. Trypanosoma cruzi Trypanosoma gambiense Trypanosoma rhodesiense Leishmania donovani
Trypanosoma cruzi
__________________ produces a disease similar to that of the Gambian form but is more virulent. It is rapidly progressive and patients frequently die before full development of the signs of meningoencephalitis. The incubation period is short and trypomastigotes appear in the blood early in the disease and in large numbers. Trypanosoma cruzi Trypanosoma rhodesiense Trypanosoma rangeli Trypanosoma gambiense
Trypanosoma rhodesiense
A 60-year-old Brazilian patient with cardiac irregularities and congestive heart failure suddenly dies. Examination of the myocardium revealed numerous amastigotes, an indication that the cause of death was most likely: Leishamanisis with Leishmania donovani Leishmaniasis with Leishmania braziliense Trypanosomiasis with Trypanosoma gambiense Trypanosomiasis with Trypanosoma cruzi
Trypanosomiasis with Trypanosoma cruzi
Which one of the following features of Taenia saginata helps distinguish it from Taenia solium?
Unarmed rostellum
The eggs of the blood fluke Schistosoma haematobium range from 110 to 170 µm long by 40 to 70 µm wide and have a sharp, pointed terminal spine. In which specimen is the organism most likely found? Ascites fluid Sputum Bile Urine
Urine
What form of leishmaniasis can mimic either typhoid fever or malaria because of symptoms which can include diarrhea and intermittent fevers? The parasite is not confined to subcutaneous tissues and mucous membranes but may occur throughout the body.
Visceral leishmaniasis
A peripheral blood smear is examined revealing the presence of microfilariae with the following characteristics: Nocturnal periodicity a size range of 245-300 µmthe presence of a sheath the tip of the tail is free of nuclei The parasitic organism which produces microfilaria that fit this description is - Brugia malayi Onchocerca volvulus Wuchereria bancrofti Loa loa
Wuchereria bancrofti
What is the specimen of choice to diagnose infection caused by Onchocerca volvulus? Blood collected from the hours of 10 pm to 4 am a skin snip Blood collected during daytime hours a stool specimen
a skin snip
What family of viruses is the causative agent of self-limited, respiratory, ocular, and gastrointestinal diseases in infants less than 4 years of age and military recruits? adenoviruses coronaviruses herpesviruses paramyxoviruses rhinoviruses
adenoviruses
A hematoxylin and eosin stained section of cardiac tissue is being examined by a pathologist. Within the cardiac muscle are parasitic forms with the following morphologic characteristics: an ovoid shape size of 3.3 X 4.5 µm an intracytoplasmic flagellum a kinetoplast an eccentrically located nucleus These forms are called: amastigotes epimastigotes promastigotes trypomastigotes
amastigotes
The middle layer of membranes surrounding the brain and spinal column is the: dura mater meninges arachnoid pia mater
arachnoid
An increase of lymphocytes and other mononuclear cells (pleocytosis) in the CSF and negative bacterial and fungal cultures is referred to as: meningoencephalitis aseptic meningitis encephalitis pleocytosis
aseptic meningitis
Large amounts of epithelial cells, many of which are covered by tiny gram-variable rods and coccobacilli, and the absence of inflammatory cells in vaginal discharge are signs of: pelvic inflammatory disease (PID) bartholinitis cervicitis bacterial vaginosis
bacterial vaginosis
The specimen of choice to demonstrate the organism which causes espundia (mucocutaneous leishmaniasis) is - liver puncture splenic puncture biopsy of the leading edge of the ulcer sternal marrow aspirate
biopsy of the leading edge of the ulcer
Which of the following is the vector for Onchocercus volvulus? mosquitos (Aedes, Anopheles, Culex, Mansonia species) mango flies (Chrysops species) black flies (Simulium species) small midges (Culicoides species)
black flies (Simulium species)
The infective stage of Schistosoma species is - cercariae (skin penetration) metacercaria in crustaceans metacercaria in fish metacercaria on water vegetation
cercariae (skin penetration)
An infection of the uterus and its contents during pregnancy is called: PID bartholinitis cervicitis chorioamnionitis
chorioamnionitis
Specialized secretory cells centrally located in the brain in the third and fourth ventricles that produce CSF are called the: choroid plexus ventricles meninges pia mater
choroid plexus
What viruses are responsible for most colds which occur during the winter? rhinoviruses coronaviruses adenoviruses rhabdoviruses togaviruses
coronaviruses
The etiologic agent of herpangina is - coxsackie A virus adenoviruses coxsackie B virus noroviruses herpes simplex viruses
coxsackie A virus
Parainfluenza virus is cause of a spasmodic laryngitis characterized by difficult breathing and a hoarse, metallic cough (said to resemble a seal's bark). This condition is known as - croup viremia orchitis Reye's syndrome whooping cough
croup
Virus induced changes in cells grown in flasks or petri dishes (cell cultures) such as inclusions (intracellular structures), necrosis, "giant" cells, cytoplasmic modifications, vacuolization, etc. are known as immunofluorescence immune adherence autofluorescence complement activation cytopathic effect (CPE)
cytopathic effect (CPE)
Virus detection by examining stained cells (tissue sections or cell cultures) using brightfield microscopy is called - virus neutralization electron microscopy cytopathology nucleic acid testing immunofluorescence
cytopathology
In the Schick test small amounts of toxin are injected under the skin to demonstrate the presence of neutralizing antibody (antitoxin). The purpose if this test is to‑ demonstrate exposure to Mycobacterium species and seroconversion demonstrate immunity to the tetanus toxin demonstrate immunity to the diphtheria toxin. demonstrate immunity to the pertussis toxin.
demonstrate immunity to the diphtheria toxin.
The diagnosis of hepatitis A virus (HAV) infection is best accomplished through - isolation and identification from a stool specimen using a cell culture demonstration of anti-HAV antibodies using enzyme immunoassay (EIA) electron microscopy to detect the virus in feces demonstration of elevated liver enzymes examination of hepatocytes for cytopathic effect (liver biopsy)
demonstration of anti-HAV antibodies using enzyme immunoassay (EIA)
The best test procedure (sensitive and specific) to diagnose hepatitis D virus (HDV) infection is based on - isolation and identification of the virus in cell culture demonstration of a rise in titer using hemagglutination inhibition electron microscopy to detect the virus in feces demonstration of antibody to the delta antigen using enzyme immunoassay (EIA) examination of hepatocytes for cytopathic effect (liver biopsy)
demonstration of antibody to the delta antigen using enzyme immunoassay (EIA)
What is the arthropod vector of the parasite which causes heartworm in dogs and cats? Crysops species (mango flies) Simulium species (black flies or buffalo gnats) Culicoides species (small midges) Phlebotomus species (sandflies) different mosquito species
different mosquito species
A 1 year old (y/o) child in severe respiratory distress is admitted to the hospital with symptoms including: fever, chills, sore throat, and dry, non-productive cough. Chest radiography (X-ray) reveals a patchy, diffuse infiltrate in both lungs, indicating viral pneumonia. The clinician suspects the etiologic agent may be respiratory syncytial virus (RSV). Select a procedure which will allow RSV to be identified quickly so effective treatment can be provided as soon as possible. direct fluorescent antibody (DFA) stain of nasal washings or sputum hemagglutination inhibition testing of patient's serum demonstrating a 4-fold rise in titer electron microscopy to demonstrate if the size and shape is characteristic for RSV applying neutral red strain to demonstrate neutralization of the virus by the patient's serum
direct fluorescent antibody (DFA) stain of nasal washings or sputum
The outermost layer of membranes surrounding the brain and spinal column is the: dura mater meninges arachnoid pia mater
dura mater
The term acute urethral syndrome is use to describe a syndrome of symptoms that include: greater than 105 colony-forming units of bacteria per milliliter (CFU/mL) or urine, dysuria, and frequent urination dysuria, frequency, and urgency but a specimen yielding fewer organisms that 105 CFU/mL urine on culture fever and flank pain, dysuria, vomiting, diarrhea, chills, increased heart rate, and lower abdominal pain dysuria, frequency and urgency along with tenderness and pain over the area of the bladder
dysuria, frequency, and urgency but a specimen yielding fewer organisms that 10^5 CFU/mL urine on culture
A 24 y/o male is experiencing malaise, fatigue, fever, sore throat, lymphadenopathy, and splenomegaly. The clinician suspects infectious mononucleosis but the Davidsohn differential absorption test for heterophil antibody is negative. Serologic testing for Epstein-Barr virus (EBV) specific antibodies is performed. The following results are obtained: VCA - IgM = positive early antigen-diffuse (EA-D) antibody = negativeVCA - IgG = negative EBV nuclear antigen (EBNA) antibody = negative Based on these results the diagnosis should be - early acute infection with EBV past infection with EBV EBV acute infection cytomegalovirus (CMV) mononucleosis
early acute infection with EBV
The period of intracellular viral synthesis where there is no visible evidence of viral replication is during which phase of the replication cycle? attachment eclipse maturation uncoating penetration
eclipse
It is possible to identify virus groups on the basis of size and shape of the virion (the infectious virus particle) using which of the following procedures? cytopathic effect (CPE) Gram stain electron microscopy neutral red stain complement fixation
electron microscopy
Chyluria is a result of lymphatic rupture and fluid entering the urine. Another lymphatic condition caused by Wuchereria bancrafti is: calabar swelling elephantiasis river blindness pruritic rash
elephantiasis
An inflammation of the brain parenchyma that is usually a result of viral infection is: meningoencephalitis aseptic meningitis encephalitis meningitis
encephalitis
Contact with the poison hairs of catepillars may cause erythema, swelling, burning, and itching. This condition is known as - myiasis infestation lepidopterism larval toxicosis erucism
erucism
Infections that are acquired during sexual activity are referred to as: endogenous infections pyelonephritis exogenous infections upper tract infections
exogenous infections
An abnormal passage between two organs or leading from an internal organ to the body surface is known as a: fistula sinus tract necrotizing fascia decubitus
fistula
An abscess that begins as a red nodule in a hair follicle that ultimately becomes painful and full of pus is a: folliculitis furuncle carbuncle erthrasma
furuncle
A patient is diagnosed with gas gangrene in the skin as a result of bullous lesions associated with sepsis. The Gram-stain reaction and morphologic features of the most probable pathogen causing this infection is: gram-positive cocci gram-positive bacilli gram-negative coccobacilli gram-negative bacilli
gram-positive bacilli
The Runyon system of classification is based on: colonial and microscopic morphologic characteristics. biochemical characteristics. growth rate and colonial pigmentation. genotypic characteristics.
growth rate and colonial pigmentation.
Most viruses can agglutinate certain species of RBC's. This hemagglutination is inhibited by neutralizing antibody. This phenomenon is the basis of (the) _?_ . virus neutralization test chemiluminescent immunoassays hemagglutination inhibition test enzyme immunoassays complement fixation test
hemagglutination inhibition test
The most common source(s) of infection in the central nervous system (CNS) is (are): hematogenous spread infections at other sites such as otitis media organisms gaining access because of anatomic defects in CNS structures bacteria that are able to travel along nerves leading to the brain
hematogenous spread
Which of the following is a defective RNA virus which is surrounded by delta antigen and HBsAg? It must be transmitted as a simultaneous infection with HBV or as a super infection of HBsAg carriers. hepatitis A virus hepatitis D virus hepatitis B virus hepatitis E virus hepatitis C virus
hepatitis D virus
Which hepatitis virus causes a self-limited disease (patients recover without treatment) transmitted by the fecal-oral route? In pregnant women it causes a more severe clinical syndrome called fulminant hepatic failure which has a much higher mortality rate. hepatitis A virus hepatitis D virus hepatitis B virus hepatitis E virus hepatitis C virus
hepatitis E virus
Small, vesicular (blister-like) lesions which coalesce to form larger, ulcerative lesions which often occur at the mucocutaneous junction of the lip (cold sores) are caused most often by - herpes simplex virus type 1 the rubella virus herpes simplex virus type 2 coxsackie virus A and B varicella-zoster virus
herpes simplex virus type 1
A 17 y/o female, who is sexually active, is suffering from painful, ulcerative lesions of the urogenital tract. Material from the base of these lesions is examined microscopically (Tsank or Papanicola preparation) revealing the presence of giant, multinucleate cells with intranuclear inclusions. This is most likely indicative of ?infection. rubeola virus coxsackie virus herpes simplex virus type 1 varicella zoster virus (VZV) herpes simplex virus type 2
herpes simplex virus type 2
For this species of fly, the gravid female fly deposits her eggs on the abdomen of biting flies, ticks, and mosquitos, which deposit the eggs on their human host when they feed. The larvae penetrate the skin producing a painful furuncular lesion. When sufficiently developed the larval form emerges from the tissues, falls to the ground, and pupates in the soil. human botfly (Dermatobia hominis) horse botfly: Gasterophilus tumbu fly (Cordylobia anthrophagia) screwworm fly (Cochliomyia hominivorax) sheep botfly (Oestrus ovis)
human botfly (Dermatobia hominis)
The etiologic agent of exanthum subitum ( or roseola infantum, an acute, self-limited disease of infants characterized by high fever and a maculopapular rash) and possibly multiple sclerosis as well, is - rubeola virus human herpes virus 6 varicella-zoster virus variola virus rubella virus
human herpes virus 6
Proper storage of cerebrospinal fluid (CSF) sent to the laboratory for bacterial culture includes: refrigeration for up to 23 hours freezing at 70oC incubation at 35oC freezing at temperatures above 70oC
incubation at 35oC
With ?, viral DNA is incorporated into the DNA of infected B lymphocytes. Viral antigen is then expressed on the surface of the infected cells stimulating T lymphocytes to divide. These activated T lymphocytes appear on the peripheral blood smear as atypical lymphocytes or "Downey cells". adenovirus infection infectious mononucleosis cytomegalic inclusion disease chicken pox genital herpes
infectious mononucleosis
The predominant organism in vaginal secretions from normal women of reproductive age is: lactobacilli Streptococcus agalactiae Enterobacteriaceae Staphylococci
lactobacilli
A culture performed on a vaginal specimen collected from a 38-year-old would likely grow primarily: group B beta-hemolytic streptococci staphylococci and corynebacteria lactobacilli, Enterobacteriaceae, streptococci, and staphylococci G. vaginalis, Prevotella spp, Peptostreptococcus spp, and Mobiluncus spp
lactobacilli, Enterobacteriaceae, streptococci, and staphylococci
Contact with the hairs of moths and butterflies, which causes dermatitis, is called -
lepidopterism
Which of the following is the vector for Loa loa? mosquitos (Aedes, Anopheles, Culex, Mansonia species) mango flies (Chrysops species) black flies (Simulium species) small midges (Culicoides species)
mango flies (Chrysops species)
A collective term used for the three layers of membranes surrounding the brain and spinal column is the: dura mater meninges arachnoid pia mater
meninges
Infection within the subarachnoid space or throughout the pia mater and the arachnoid membrane is referred to as: meningoencephalitis aseptic meningitis encephalitis meningitis
meningitis
A condition characterized by concomitant meningitis that occurs with encephalitis is called: meningoencephalitis aseptic meningitis encephalitis pleocytosis
meningoencephalitis
The infective stage of Fasiolopsis buski and Fasciola hepatica is - cercariae (skin penetration) metacercaria in crustaceans metacercaria in fish metacercaria on water vegetation
metacercaria on water vegetation
The infective stage for Paragonimus westermani (the lung fluke) is ingestion of - embryonated eggs in contaminated food/water metacercariae in crustaceans (crabs/crayfish) metacercariae in the flesh of fish metacercariae (bamboo shoots/water chestnuts)
metacercariae in crustaceans (crabs/crayfish)
The infective stage for Chagas' disease (American sleeping sickness) is the - Amastigote epimastigote promastigote metacyclic trypomastigote
metacyclic trypomastigote
Which of the following is the vector for Brugia malayi? mosquitos (Aedes, Anopheles, Culex, Mansonia species) mango flies (Chrysops species) black flies (Simulium species) small midges (Culicoides species)
mosquitos (Aedes, Anopheles, Culex, Mansonia species)
Which of the following is the vector for Wuchereria bancrofti? mosquitos (Aedes, Anopheles, Culex, Mansonia species) mango flies (Chrysops species) black flies (Simulium species) small midges (Culicoides species)
mosquitos (Aedes, Anopheles, Culex, Mansonia species)
Which virus usually causes a mild disease in children, characterized by an inflamed pharynx and swollen parotid (salivary) glands, but may cause orchitis (inflammation of the testicles) and ovaritis in adults? measles echoviruses rubella rabies mumps
mumps
Which of the following is the causative agent of orchitis? mumps virus Chlamydia trachomatis Gardnerella, Prevotella spp, Porphyromonas spp, Peptostreptococcus spp, Mobiluncus spp N. gonorrhoeae and C. trachomatis
mumps virus
A stool specimen is sent to the laboratory for examination. Eggs with the following characteristics are recovered: a size range of 30-47 µm a spherical or broadly ovoid shape a thin to moderately thick shell a six-hooked onchosphere with bipolar knobs and filaments What parasite should be reported? Taenia species Diphyllobothrium latum Dipylidium caninum Hymenolepis diminuta Hymenolepis nana
nana
Viral pneumonia caused by influenza A can usually be treated effectively with - oseltamivir (Tamiflu) or zanamivir (Relenza) ribavirin azidothymidine (AZT) and protease inhibitors acyclovir
oseltamivir (Tamiflu) or zanamivir (Relenza)
Tests to demonstrate antibodies to EBV using the Davidsohn differential absorption test for heterophil antibody is negative. Serologic testing for Epstein-Barr virus (EBV) specific antibodies is performed. The following results are obtained: VCA - IgM = negative early antigen-diffuse (EA-D) antibody = negativeVCA - IgG = positive EBV nuclear antigen (EBNA) antibody = positive Based on these results the diagnosis should be - Early acute infection with EBV past infection with EBV EBV acute infection cytomegalovirus (CMV) mononucleosis
past infection with EBV
The term ? refers to an organism which derives part or all of its nourishment from the host and in the process causes injury to the host by its mechanical, traumatic, or toxic activities. spurious parasite obligate parasite pseudoparasite pathogenic parasite commensal parasite
pathogenic parasite
Which of the following media is selective for gram positive bacteria (inhibits the growth of gram negative bacteria)? This medium is used to isolate gram positive cocci such as staphylococci and streptococci from specimens taken from areas colonized by other microbes. phenylethanol agar (PEA) Martin-Lewis modified Thayer-Martin MacConkey Buffered charcoal yeast extract (BCYE
phenylethanol agar (PEA)
The innermost membrane layer surrounding the brain and spinal column is the: dura mater meninges arachnoid pia mater
pia mater
The specimen of choice to diagnose Enterobius vermicularis (pinworm) infection is - stool: Direct Wet Mount (DWM) and Concentration (Conc.) procedure. pinworm paddle lung tissue: Gomori Methenamine Silver (GMS) stain or Giemsa stain. serum to demonstrate a significant rise in antibody titer (serology) material aspirated from a hydatid cyst (hydatid sand)
pinworm paddle
Which virus, in the Enterovirus family, causes a febrile illness that may result in irreversible paralysis (0.1% of the cases)? The first vaccine against this virus was developed by Jonas Salk but an oral vaccine (an attenuated strain) developed by Albert Sabin was used for mass inoculation, virtually eradicating the virus from the United States. herpes simplex virus (HSV) coxsackie viruses human immunodeficiency virus (HIV) eastern equine encephalitis virus poliovirus
poliovirus
A 6-year-old girl is diagnosed with a bullous impetigo infection. Based on this information, the catalase and coagulase results of the infecting organism are expected to be catalase-_____ and coagulase-_____. negative; negative positive; negative positive; positive negative; positive
positive; positive
The infective stage for Leishmania donovani is the - amastigote epimastigote promastigote metacyclic trypomastigote
promastigote
The presence of cytoplasmic inclusions in nerve cells (negri bodies) is a confirmatory test for the diagnosis a fatal viral encephalitis known as - eastern equine encephalitis (EEE) HSV type 1 encephalitis western equine encephalitis (WEE) rabies St. Louis encephalitis (SLE)
rabies
The major cause of the common cold during the fall and spring are - rhinoviruses coronaviruses adenoviruses rhabdoviruses togaviruses
rhinoviruses
The etiologic agents of infant gastroenterititis whose morphology resembles a wheel with a large hub and short spokes because of its double-shelled capsid are - noroviruses rotaviruses coronaviruses influenza viruses togaviruses
rotaviruses
The presence of Koplick's spots (bright red spots with a blue-white central speck on the mucosa of the lips and oral cavity) is diagnostic for - rubella (German measles) rubeola (measles) mumps norovirus infection coxsackie A virus infection
rubeola (measles)
This female fly lays eggs on unbroken skin or wounds. When the eggs hatch, the larvae burrow deeply into healthy tissue or bone. This is particularly dangerous if the larvae migrate into the middle ear, nasal sinuses and the brain. Even if the host dies the larvae will continue to thrive in the dead body. What is the name of this species of fly? human botfly (Dermatobia hominis) horse botfly: Gasterophilus tumbu fly (Cordylobia anthrophaga) screwworm fly (Cochliomyia hominivorax) sheep botfly (Oestrus ovis)
screwworm fly (Cochliomyia hominivorax)
In late winter and early spring the respiratory syncytial virus is responsible for outbreaks of ? in nurseries. croup viremia orchitis Reye's syndrome severe respiratory distress and viral pneumonia
severe respiratory distress and viral pneumonia
Transmission of Ancylostoma duodenale (old world hookworm) infection (infective stage) is through - skin penetration by filariform larvae in soil ingestion of cysticercus larvae in beef ingestion of cysticercoid larvae in grain skin penetration by rhabditiform larvae ingestion of embryonated eggs in contaminated food or water
skin penetration by filariform larvae in soil
Which of the following is the vector for Mansonella perstans? mosquitos (Aedes, Anopheles, Culex, Mansonia species) mango flies (Chrysops species) black flies (Simulium species) small midges (Culicoides species)
small midges (Culicoides species)
The specimen of choice to diagnose infection caused by Paragonimus westermani(the lung fluke) is a -
sputum or stool specimen
The predominant organisms in vaginal secretions from normal prepubescent girls and postmenopausal women are: lactobacilli S. agalactiae Enterobacteriaceae staphylococci
staphylococci
A culture performed on a vaginal specimen collected from a 60-year-old woman would likely grow primarily: group B beta-hemolytic streptococci staphylococci and corynebacteria Enterobacteriaceae, streptococci, staphylococci, lactobacilli, and anaerobes G. vaginalis, Prevotella spp., Peptostreptococcus spp., and Mobiluncusspp.
staphylococci and corynebacteria
The specimen of choice to demonstrate visceral leishmaniasis is ? because it is the procedure which carries the least amount of risk to the patient. Other procedures may be more productive but the risk of uncontrolled hemorrhage is much greater and patients may bleed to death. splenic puncture liver puncture sternal marrow aspirate cardiac stick
sternal marrow aspirate
Humans contract Chagas disease when the reduviid bug defecates while taking a blood meal and the parasites in the feces are rubbed or scratched into the bite wound or onto mucosal surfaces. Which stage in the blood infects the host cells? amastigote epimastigote trypomastigote promastigote
trypomastigote
The vector Glossina palpalis group transmits the Trypanosoma brucei gambiense organism. The diagnostic stage is the: amastigote epimastigote trypomastigote promastigote
trypomastigote
The female fly of ? lays her eggs in feces and urine-contaminated soil or clothing. The larvae hatch and penetrate the skin. This arthropod is a major cause of cutaneous myiasis in Africa.
tumbu fly (Cordylobia anthrophagia)
The period, during viral replication where the capsid is removed by host enzymes is called - absorption eclipse penetration maturation uncoating
uncoating
Mucosal antibacterial properties, a valvelike mechanism, host immune responses, and defensins are all host defense mechanisms found in the ________ tract. digestive upper respiratory urinary genital
urinary
Most viruses are shed from the respiratory or gastrointestinal tracts but the specimen of choice to diagnose cytomegalovirus (CMV) infection is/are - throat swabs nasal washings feces urine fluid from vesicular lesions
urine
An infection of the vaginal mucosa resulting in an abnormal discharge and offensive odor or itching is referred to as: chorioamnionitis bartholinitis cervicitis vaginitis
vaginitis
Shingles is caused by reactivation of - HSV type 1 rubella virus HSV type 2 coxsackie virus varicella zoster virus
varicella zoster virus
The flora of the female genital tract: consists primarily of staphylococci, corynebacteria, and Neisseria consists primarily of Enterobacteriaceae, streptococci, and staphylococci. consists primarily of S. agalactiae and staphylococci varies with the pH and estrogen concentration of the mucosa
varies with the pH and estrogen concentration of the mucosa
The large, fluid-filled spaces within the brain are called the: choroid plexus ventricles meninges pia mater
ventricles
In the ? test a suspension of the test virus and patient serum are mixed and incubated. If antibody directed against the virus is present in the patient's serum it will destroy the ability of the virus to infect cells. This is tested by adding the mixture (virus suspension and patient serum) to a cell culture and looking for cytopathic effect. If infectivity of the test virus is lost due to specific antibody in the serum of the patient, there will be no cytopathic effect in the cell culture. If the patient does not have the viral infection there is no antibody to prevent the virus from infecting the cells of the cell culture and cytopathic effect will be seen. virus neutralization complement fixation hemagglutination inhibition indirect fluorescent antibody enzyme immunoassay
virus neutralization
Which of the following is the mode of transmission of Dracunculus medinensis? Ingestion of __?___. Swine Copepods Crabs Snails
Copepods
The resident microflora that can colonize the bladder and other structures of the urinary tract are: Enterobacteriaceae yeast Propionibacterium acnes Corynebacteria
Corynebacteria
The stage in a protozoan parasite's life cycle that is resistant to the environment and allows existence outside the body of the host is called the- Egg Cyst Trophozoite Larva Oöcyst
Cyst
Which second intermediate host ingests the cercariae of Clonorchis? Snail Crustacean Copepod Freshwater fisH
Freshwater fisH
The only intermediate host required in the life cycle of blood flukes is a: Copepod Crustacean Freshwater snail Freshwater fish
Freshwater snail
The most predominant anaerobe isolated in animal bites is: Veillonellaspp Clostridium spp Prevotellaspp Fusobacteriumspp
Fusobacteriumspp
The type of vaginitis referred to as bacterial vaginosis is thought to be caused by: Gardnerella vaginalis S. agalactiae Lactobacillusspp. Enterococcusspp.
Gardnerella vaginalis
Which of the following is the causative agent of bacterial vaginosis? mumps virus Chlamydia trachomatis Gardnerella, Prevotella spp, Porphyromonas spp, Peptostreptococcus spp, Mobiluncus spp N. gonorrhoeae and C. trachomatis
Gardnerella, Prevotella spp, Porphyromonas spp, Peptostreptococcus spp, Mobiluncus spp
The trophozoites of ? are found in the small intestine and can be demonstrated using the string test or by examining a duodenal aspirate. In a saline direct wet mount from a fresh specimen, the organism exhibits "falling leaf" motility. Giardia duodenalis Pentarichomonas hominis Dientamoeba fragilis Chilomastix mesnili Balantidium coli
Giardia duodenalis
Which protozoan parasite exhibits "falling leaf" motility? Trichomonas hominis Chilomastix mesnili Trichomonas vaginalis Dientamoeba fragilis Giardia lamblia
Giardia lamblia
Which of the following is the vector for Trypanosoma brucei gambiense?
Glossina (Tsetse flies)
Infection by this tissue nematode involves ingestion of pickled or poorly cooked fish, fowl, frogs, or snakes (all of which may serve as a second intermediate host). The spiny-headed larval forms do not mature but continue to migrate through the body of infected humans.
Gnathostoma spinigerum
Infection by this tissue nematode involves ingestion of pickled or poorly cooked fish, fowl, frogs, or snakes (all of which may serve as a second intermediate host). The spiny-headed larval forms do not mature but continue to migrate through the body of infected humans. Angiostrongylus cantonensis Dracunculus medinensis Angiostrongylus costaricensis Gnathostoma spinigerum Dirofilaria immitis
Gnathostoma spinigerum
In the phylum Arthropoda, segmented wormlike organisms which mature through a series of instars are called - Pupae Nymphs Larvae Imagos Nit
Larvae
What is the name of the spider (the most venomous in North America) which delivers a bite that is especially dangerous to children? The female is easily recognized because it is shiny, black, and usually has a red, hourglass-shaped marking on the dorsal side of her spherical shaped abdomen. Latrodectus mactans (black widow) Dermacentor andersoni (wood tick) Loxosceles reclusa (brown recluse) Sceliphron caementarium (mud dauber) Centruroides exilicauda(scorpion)
Latrodectus mactans (black widow)
What hemoflagellate causes a form of cutaneous leishmaniasis which can spread to mucous membranes (mucocutaneous leishmaniasis)? The lesions are erosive and if untreated may lead to loss of the soft parts of the nose, lips, and soft palate. Leishmania braziliensis Leishmania mexicana Leishmania donovani Leishmania tropica
Leishmania braziliensis
The characteristic lesions associated with ? are moist, ulcerative lesions which tend to ulcerate very early. They are seen primarily on the lower limbs and there may be secondary or satellite lesions. This disease is primarily a disease of rural areas and rodents (resevoir hosts) serve as important sources of human infection. Leishmania major Leishmania donovani Leishmania tropica Leishmania Mexicana
Leishmania major
What hemoflagellate causes an acute skin disease with a duration of 3 to 6 months? The lesions are moist, ulcerate early in the course of the disease, and are primarily on the lower limbs. Multiple lesions may be seen. Leishmania major Leishmania braziliensis Leishmania tropica Leishmania mexicana
Leishmania major
Which form of American cutaneous leishmaniasis is usually characterized by a single lesion, most often found on the ear with extensive destruction of cartilage possible? Leishmania major Leishmania pifanoi Leishmania mexicana Leishmania braziliensis
Leishmania mexicana
What hemoflagellate causes a diffuse cutaneous visceral leishmaniasis which can spread over the body? The lesions do not ulcerate and bear a resemblance to lepromatous lesions. Even though infected, the patient remains in good health. Leishmania braziliensis Leishmania donovani Leishmania Mexicana Leishmania pifanoi
Leishmania pifanoi
What hemoflagellate causes a chronic skin disease (lasting a year or more) characterized by a single, dry, ulcerative lesion found primarily on the face? This chronic illness lasts a year or more. Leishmania tropica Leishmania pifanoi Leishmania major Leishmania braziliensis
Leishmania tropica
A peripheral blood smear is made on a patient from Nigeria who is suspected of having filariasis. When the smear is examined, microfilariae with the following characteristics are found: diurnal periodicity a size range of 250-300 µm the presence of a sheath nuclei which extend into the tip of the tail The parasitic organism which produces microfilaria that fit this description is - Brugia malayi Onchocerca volvulus Wuchereria bancrofti Loa loa
Loa loa
The scientific name (genus-species) of the parasite known as the African eye worm comes from its African name. It is most conspicuous and irritating when adults cross the conjuctiva. Removal involves the use of a 10% cocaine solution to immobilize adult worms. What is the genus-species name of the African eyeworm? Brugia malayi Onchocerca volvulus Wuchereria bancrofti Loa loa
Loa loa
Which species of nematode produces microfilariae which exhibit diurnal periodicity (occur in the blood in greatest number during the daylight hours)? Wuchereria bancrofti Onchocerca volvulus Loa loa Brugia malayi
Loa loa
