exam 4 microbio

Please select the bacterial genus that has similar features to Pseudomonas and a comparable mode of operation.

Acinetobacter

What bacterial species has become a high-profile pathogen associated with drug-resistant infections in military personnel with combat injuries?

Acinetobacter baumannii

How does the toxin enter the cell?

After B binds to host cell receptors, both A and B enter the host cell by endocytosis.

After the A-B toxin enters the cell,

B is removed by exocytosis.

Which of the following organisms would look most similar to Neisseria meningitidis on a Gram-stained smear?

Branhamella catarrhalis

Please select the explanation for why cancer patients have a higher risk of getting more serious listeriosis infections.

Cancer patients are immunosuppressed, and this increases the severity of this disease.

Please choose the answer that indicates the significance of E. coli O157:H7 to test your understanding of this organism.

Its role in food-borne illness outbreaks has prompted random testing and required labeling of meat products.

Having received no prenatal care, a young woman arrives at a hospital after many hours of labor and delivers a baby girl. Three days later the baby girl is listless, nursing poorly, and is running a fever. Blood cultures are done, and after 24 hours, they are Gram stained and show the presence of gram-positive cocci in pairs and short chains. Upon subculture, these form colonies that are beta hemolytic on blood agar. Further tests demonstrate that the isolate is catalase negative, resistant to bacitracin, and is CAMP test positive. What is the identification of this organism?

Streptococcus agalactiae

Which bacterium is considered a group B Streptococcus?

Streptococcus agalactiae

Which pathogen is the most common cause of neonatal pneumonia, sepsis, and meningitis in the United States?

Streptococcus agalactiae

An 8-month-old infant has been brought to the ER with a high fever. Her parents indicate that she has not been eating or drinking well and has been very irritable until the last few hours during which she has been only minimally responsive. Suspecting meningitis, a spinal tap is done and the CSF sample is sent to the lab for analysis. The white blood cell count on the sample is profoundly elevated, the protein content is elevated, and the glucose level is depressed. The Gram-stained smear shows gram-positive cocci in pairs. Cultures are done and after overnight incubation, alpha hemolytic colonies are observed on the blood plate. These colonies contain gram-positive cocci, which are catalase negative. An optochin susceptibility test is done and there is a large zone of inhibition around the disk. What is the identification of this isolate?

Streptococcus pneumoniae

A positive Quellung reaction, or capsular swelling, is confirmatory for

Streptococcus pneumoniae.

Most cases of otitis media in children are due to infection with

Streptococcus pneumoniae.

Scarlet fever is caused by strains of

Streptococcus pyogenes.

All of the following are correct about Streptococcus pyogenes, except

most strains do not have a capsule.

In the absence of a bacterial sample of Staphylococcus epidermis, a student could swab their

nose

All species of Staphylococcus

produce catalase.

The M protein of Streptococcus pyogenes

protects against phagocytosis and enhances adherence.

Streptococcus pyogenes causes all the following, except

scalded skin syndrome.

Infections caused by Staphylococcus aureus include all of the following, except

sore throat.

Effective treatment of abcesses due to MRSA infection generally includes __________.

surgical draining of the abscess to clear it of pus and other foreign bodies

After diagnosing 19 cases of legionellosis among Disneyland visitors or employees, health officials likely

tested water within the cooling towers for the presence of bacteria.

Patients suffering from anthrax are typically given the antibiotic ciprofloxacin, but may still die because

the antibiotic does nothing to inhibit the action of anthrax toxin.

All of the following are correct about Staphylococcus aureus, except

the body's most powerful defense against it lies in the T-cell response.

In the name of the bacterium E. coli O157:H7 the O and H represent

the flagellar antigen and the cell wall antigen.

Infections with Mycobacterium fortuitum, Mycobacterium abscessus, and Mycobacterium chelonae typically occur when

the host defenses are compromised through medical procedures.

All the following pertain to Staphylococcus epidermidis infections, except

the organism produces a large number of tissue damaging enzymes and toxins.

Long-term sequelae of Group A streptococcal infections include all the following, except

transmission of sequelae via respiratory secretions from a patient with streptococcal sore throat.

Early onset Group B Streptococcal infection of infants is generally prevented by

treating the mother with intravenous penicillin throughout labor.

Primary tuberculosis is marked by

tubercles in the lungs.

Pulmonary nocardiosis has symptoms that are very similar to ________.

tuberculosis

Please choose the high-risk population for contracting brucellosis.

veterinarian

Please select the age group that is predominantly affected by both cutaneous and pharyngeal S. pyogenes infection.

young children and pre-adolescents

In A-B toxins,

A is the toxic part.

Production of enterotoxin is a characteristic of

Clostridium difficile.

Anthrax is

All of the choices are correct.

Treatment and control of anthrax include

All of the choices are correct.

Disease/s caused by Streptococcus pneumoniae include

All of these choices are correct.

Neisseria gonorrhoeae is

All of these choices are correct.

Please choose the correct statement comparing Bacillus cereus to Clostridium perfringens.

All of these choices are correct.

Please select possible transmission method(s) for Legionella pneumophila.

All of these choices are correct.

Please select the answer that describes the state of diagnostics for tuberculosis infections.

All of these choices are correct.

Please select the explanation for why day-care centers are often associated with food-borne illnesses caused by Shigella.

All of these choices are correct.

Scarlet fever involves

All of these choices are correct.

The viridans streptococci are

All of these choices are correct.

Production of a neurotoxin that binds to target sites on spinal cord neurons responsible for inhibiting skeletal muscle contraction is a characteristic of

Clostridium tetani.

Which is not correct about Bacillus cereus?

Causes a zoonosis

A patient has a deep wound infection, and the specimen taken for microbial identification in the lab is a tissue sample from within the wound. Please choose the most likely organism causing the infection.

Clostridium

Which form of anthrax involves a black eschar on the skin?

Cutaneous

Common traveler's diarrhea is usually due to infection with

Escherichia coli.

Please select the pathogen from the genus Streptococcus that correctly represents the most serious pathogen of this group.

Group A beta-hemolytic S. pyogenes

A pregnant woman is told she has a positive CAMP test and should be treated with a course of antibiotics. This test is indicative of

Group B streptococci.

Please choose the reason why gas gangrene infections can be treated with oxygen therapy successfully.

High pressure oxygen is delivered to the infected tissue, creating an unfavorable habitat for anaerobic Clostridium.

Please select the answer that explains how humans most commonly contract plague.

Humans are accidental hosts when they get between the flea and its preferred rodent hosts.

Which chemical produced by S. aureus is also known as "spreading factor"?

Hyaluronidase

If left untreated, an infection with __________ can lead to pelvic inflammatory disease and infertility.

Neisseria gonorrhoeae

In which of the following situations would Staphylococcus epidermidis be the most likely etiologic agent?

Infected IV catheter site

Please choose the answer that explains how the chemical leukocidin, produced by S. aureus, affects the host.

Inflammation and phagocytosis are severely compromised.

Please select the disease that Haemophilus bacteria do not cause.

Influenza

Which is incorrect about Staphylococcus aureus food intoxication?

Ingestion of the pathogen allows it to multiply and damage the GI tract lining.

A patient has a suspicious skin infection and a culture is taken. Which media would be appropriate to select for staphylococci?

Mannitol salt agar

Acinetobacter baumanii has become a high-profile opportunistic pathogen, causing wound infections, urinary tract infections, pneumonia, and septicemia. What is the reason for its high-profile nature?

Many strains of A. baumanii are highly resistant to antibiotics.

The instillation of antibiotics in newborn's eyes will prevent ophthalmia neonatorum in newborns. This disease is caused by

Neisseria gonorrhoeae.

Please choose the correct statement that differentiates N. meningitidis and N. gonorrhoeae.

N. meningitidis is often a normal microbiota organism that causes no symptoms, whereas N. gonorrhoeae is not a member of the normal microbiota.

Sue brought her daughter Amy to the pediatrician complaining of a sore throat. The physician examines Amy and observes that her throat is bright red and there are white pus-filled nodules on her tonsils. Which of the following conclusions should be made?

She should have a rapid strep test performed before a diagnosis is made.

Please choose the correct statement about pneumococcal pneumonia.

Pneumonia is a common secondary infection, occurring after a person's defenses are depleted.

Please select the genus which represents an opportunistic noncoliform.

Proteus

Which type of anthrax is called "woolsorter's disease"?

PulmonaryCorrect

Please choose the answer that describes why serological testing is very commonly done on streptococcal bacteria.

Serological testing, using antigen-antibody testing, is a fast way to identify bacterial species.

The patient is a 34-year-old man, who is complaining of night sweats, weight loss, diarrhea, and fatigue. He is diagnosed with Mycobacterium avium complex. Please select the explanation that describes why this patient might have this disease.

The patient has AIDS.

Foods are often salted (dried fish), acidified (chopped garlic), or desiccated (dried milk) to prevent the growth of bacteria. Which bacterial species could still be a threat under these conditions?

Staphylococcus aureus

Which pathogen has drug-resistant strains called MRSA?

Staphylococcus aureus

Occasionally, an episode of food poisoning occurs which centers around processed ham, sausage, or salted pork. These episodes are almost always assumed to be due to ingestion of Staphylococcus aureus unless other evidence proves differently. This is because

Staphylococcus aureus is one of the few bacteria able to multiply in foods as salty as sausage, ham, or salted pork.

One reason Staphylococcus aureus can be spread through the sharing of athletic equipment is that __________.

Staphylococcus aureus is resistant to salt, and its growth is not inhibited by sweat

A 48-year-old man has had nasal surgery and absorbent material has been inserted into his nasal cavity to control bleeding. Several hours ago he began to complain of a headache and has since developed a red rash over much of his body and is experiencing muscle cramps and diarrhea. His blood pressure has dropped to 75/50 mg Hg. This patient's illness is most likely caused by

Staphylococcus aureus — toxic shock syndrome toxin

A common food intoxication is caused by enterotoxin-producing strains of

Staphylococcus aureus.

Which of the following would be found in the scalp?

Staphylococcus capitis

Which of the following is commonly found on the human skin?

Staphylococcus epidermis

Please choose the statement that explains why patient specimens have to be plated and cultured using differential and selective media for laboratory diagnosis of staphylococcal infections.

Staphylococcus grows in areas of the body that are highly populated with normal microbiota, so these media inhibit other microorganisms, making it easier to find staphylococci.

Please choose the species of Staphylococcus that is not a human pathogen.

Staphylococcus pyogenes

Which organism is associated with commonly causing urinary tract infections in sexually active young adult and adolescent females?

Staphylococcus saprophyticus

Which chemical, produced by S. aureus, digests blood clots?

Staphylokinase

Why is antibiotic use a common cause of Clostridioides difficile infections?

The antibiotic wipes out the normal bacteria in the gut, allowing C. difficile to overgrow.

Please select the statement that best explains why leprosy is mainly a skin disease.

The bacterium M. leprae grows best at the cooler temperature of 30 degrees C.

Please choose the feature which allows Brucella to be an exemplary pathogen.

The bacterium can live within macrophages, and therefore, it can be carried to locations around the body as the WBCs move.

Please select the answer which describes why pulmonary anthrax is more deadly than cutaneous anthrax.

The destruction of macrophages reduces host resistance.

Please select the statement that explains why it is important to be able to differentiate between the coliform and noncoliform members of the Enterobacteriaceae family.

The noncoliform bacteria are the true pathogens of this family, while the coliforms are opportunistic pathogens.

A patient in emergency has been in a car accident, and the doctors are worried about pulmonary aspiration of gastric contents. The ER staff inserts an endotracheal tube into the trachea and sends him off to the floor to a hospital room. Now, four days later, he has an infection, and the culprit has been identified by the microbiology lab as Pseudomonas aeruginosa. Please select the answer that best explains why he now has this pulmonary infection.

The invasive intubation procedure allowed the entry of the bacterium into the relatively microbial-free environment of the lung.

Please select the statement that best explains why leprosy patients have deformed extremities.

The nerves, damaged by the bacterium, cannot send sensory information to the brain, so the person does not know when tissue damage has been done.

John has been diagnosed with gonorrhea and he is worried about his ex-girlfriend, with whom he had been having sex. But she hasn't said anything about it to him, so he just decides to not say anything. Please choose the statement that best explains why his girlfriend does not have symptoms.

The rate of symptoms, particularly in women, can be very low.

Please select the answer that explains how the E. coli O157:H7 strain can have a large systemic effect.

The toxin produced by the bacteria is spread by blood, disrupting protein synthesis within cells of the body.

Please select the explanation for why the members of the bacterial family Enterobacteriaceae are commonly pathogenic to humans.

This family of bacteria commonly inhabits the human body as normal flora.

Please select the explanation for why the E. coli 0157:H7 is such a potent pathogen.

This strain of E. coli makes an extra toxin in addition to its endotoxin.

Please select the correct explanation for why Erysipelothrix rhusiopathiae is considered to be an occupational pathogen.

Workers handling animals or their wastes are at risk for transmission.

All of the following pertain to gonorrhea, except

a chancre-type lesion develops at the portal of entry.

Streptococcus pneumoniae is

a gram-positive diplococcus with a capsule.

Rebecca Lancefield differentiated streptococci on the basis of differences in their

cell wall carbohydrates in a serological test.

People at greatest risk for pneumococcal infections include all the following, except

adolescents and young adults.

The most common site where carriers of Staphylococcus aureus carry this pathogen is

anterior nares (nostrils).

Please choose the feature of Pseudomonas that makes it a difficult organism to control in a hospital environment.

antibiotic resistance

Bacillus species commonly produce _________, which have been an important contribution to human health.

antibiotics

Symptoms of Toxic Shock Syndrome include all the following, except

appearance of flesh being "eaten" down to the muscle.

Necrotizing fasciitis is

associated with strains of Streptococcus pyogenes producing destructive enzymes and toxins.

Meningococcemia is

associated with vascular hemorrhage and petechiae.

The tetanus immune globulin used to treat the patient in this case was meant to

bind to tetanus toxin.

Please choose the correct mechanism of botulinum toxin.

blocks the release of acetylcholine neurotransmitter from the axon foot vesicles so muscle cannot get message to contract

The food-borne disease that involves neurotoxin is

botulism

The flea is the vector that carries the Yersinia bacterium from animal to animal, causing _______ plague.

bubonic

In the lab students were given two samples of bacteria; both were exposed to hydrogen peroxide. Bacterial sample #1 exhibited bubbles, whereas bacterial sample #2 did not. What enzyme was detected in sample #1?

catalase

Staphylococci can be differentiated from streptococci by the

catalase test.

Please select the mammal population that receives the greatest percentage of anthrax vaccine because it is at the highest risk of getting the disease.

cattle

The enzyme that coagulates plasma is

coagulase.

A patient's infection spreads rapidly through the lungs. The mixture is of exudate, cells, and bacterial cells that have solidified the air space. This is called

consolidation

Which occupation would carry the greatest risk of contracting a Mycobacterium marinum infection?

employee at a fish store

The O antigen of Enterobacteriaceae cell walls consists of lipopolysaccharide, which has a lipid portion referred to as _________.

endotoxin

The Group A streptococcal infection that has symptoms of fever, edema of skin near portal of entry, and an elevated red, hot vesicular lesion is

erysipelas.

The toxin of Staphylococcus aureus strains that causes blisters and desquamation of skin in scalded skin syndrome is

exfoliative toxin.

Please choose the most serious illness associated with E. coli.

hemolytic uremic syndrome

Please select the answer that differentiates between typhoidal and non-typhoidal salmonelloses.

if the organism moves into the blood and replicates

In this case, a positive skin test for tuberculosis was considered to be any reaction greater than 5 mm in diameter, as opposed to the normal cutoff of 10 mm. This was likely done because

investigators sought to increase the liklihood of identifying even those testing weakly TB positive.

All of the following pertain to Enterococcus faecalis, except

it belong to Lancefield Group B streptococci.

All of the following pertain to Neisseria meningitidis, except

it is a common cause of bacterial pneumonia.

All of the following are associated with subacute endocarditis, except

it is caused by immune system autoantibodies that attack heart and valve tissue.

All of the following pertain to Clostridium difficile infection, except

it is due to ingestion of contaminated, improperly stored, cooked meats and gravies.

Staphylococcus aureus is troublesome in the hospital environment because __________.

it is resistant to concentrations of salt that would inhibit the growth of most bacterial species

Streptococcal pharyngitis involves all the following, except

it is usually caused by the viridans streptococci.

The main distinction between the coliforms and noncoliforms is the ability to utilize _______ as a nutrient.

lactose