MediaLab Practice Exam 1

A rejuvenation solution may be used up to how many days following expiration of a red cell unit?

3 days

An aqueous 2.00 M HCl solution is prepared with a total volume of 0.475 L. The molecular weight of HCl is 36.46 g/mol. What mass of hydrochloric acid (in grams) is needed for the solution?

34.6 g

Which of the following is a mechanism known to cause platelet satellitosis (satellitism)? - An antibody directed against factor VIII - An antibody directed against von Willebrand factor (vWF) - An antibody directed against the platelet membrane - An antibody directed against fibrinogen

An antibody directed against the platelet membrane

What antibody cause ABO HDFN

Anti-A,B

Which of the following D variants has the best likelihood to receive D-positive RBCs without any adverse effects? - Del - Partial D - Partial weak D - C in Trans to RHD

C in Trans to RHD

A tech receives a call from the floor regarding antimicrobial therapy. The patient culture yielded an aerobic Gram-negative bacillus and the physician would like to use an antibiotic that inhibits cell wall synthesis. Which of the following antibiotics would be the best choice? - Gentamicin - Tetracycline - Ciprofloxacin - Cefazolin

Cefazolin

A monoclonal B-cell population (Kappa or Lambda predominant) with expression of CD19, CD20, CD23, and co-expression of CD5 is consistent with which of the following? - A normal B cell - Chronic lymphocytic leukemia - Mantle cell lymphoma - A mature T cell

Chronic lymphocytic leukemia

Which of the following clinical laboratory departments performs the most tests?

Clinical Chemistry

____________ focuses on the relationships between xenobiotics and disease states. This area emphasizes not only diagnostic testing but also therapeutic intervention

Clinical toxicology

Which one of the following statements about lipoproteins is FALSE: - Elevated LDL causes a decreased risk of atherosclerosis - Reduced LDL causes a decreased risk of atherosclerosis - Elevated HDL causes a decreased risk of atherosclerosis - Elevated total cholesterol causes an increased risk of atherosclerosis

Elevated LDL causes a decreased risk of atherosclerosis

________________ includes the evaluation of environmental chemical pollutants and their impact on human health.

Environmental toxicology

___________________ is characterized by agranular platelets and mild thrombocytopenia.

Gray platelet syndrome

Which type of antibodies are known to cause transfusion-related acute lung injury (TRALI) reactions?

HLA antibodies

Which strictly human pathogen causes chancroid, a highly contagious, sexually transmitted genital ulcer disease?

Haemophilus ducreyi

The alkaline hemoglobin electrophoresis pattern shown on the right includes controls for A, S, and C; and A and F above and below the patient results. (NOTE: ASC and AF are labeled for the controls and do not indicate the migration order.) The patient was tested in duplicate, and the results are in lanes 3 and 4. The patient lanes (3 and 4) displayed in these hemoglobin electrophoresis patterns are consistent with what diagnosis?

HbS/HPFH

A new tech has a presumptive Shigella species via biochemical identification on a stool culture. To confirm, serological testing is performed. The serological testing is negative and the quality control which was run simultaneously passed. What should the tech do next?

Heat a suspension of the organism and then repeat the serological testing

Which test is considered a more reliable method of monitoring long-term diabetes control? - Random plasma glucose - Hgb A1c - Glucose oxidase - Hexokinase

Hgb A1c

The second fasted moving hemoglobin in alkaline hemoglobin electrophoresis is ______________

Hgb F

_______________________ infection occurs after inhalation of conidia from infective structures in the environment.

Histoplasma capsulatum

Anti-A,B is what type of antibody?

IgG

_____has a half-life of 1-3 days; it is the first antibody produced in an immune response.

IgM

A patient presents with an elevation of unconjugated bilirubin, normal serum alkaline phosphatase, normal liver enzymes, and no bilirubin in the urine. This combination would suggest:

Increased rate of hemolysis.

Illustrated in the top photograph is a 3 day old colony incubated at 30o C, with a border to border white hair-like mycelium with peripheral borders of brown and brown-black pigmentation. Although consistent with one of the Zygomycetes, a genus/species identification cannot be made. Observed in the high power photomicrograph is a lactophenol blue stained mount of a fruiting head in which a non-septate hypha terminates in a bulbous columella (arrow) that extends into a spherical sporangiophore. Rhizoids were not observed. From these observations, select from the multiple choices the name of this isolate.

Mucor species

_________________ is a dermatophyte that commonly causes an itching, scaling skin infection of the feet, known as tinea pedis.

Trichophyton rubrum

What condition is indicated by the following arterial blood gas results? Bicarbonate = 32 mmol/L (Normal = 22 - 29 mmol/L) pCO2 = 65 mm Hg (Normal = 35 - 45 mmHg) pH = 7.28 (normal = 7.35 - 7.45)

Uncompensated respiratory acidosis

Which of the following signs and symptoms may be associated with immediate transfusion reaction, but is NOT usually associated with delayed hemolytic transfusion reaction?

Unexplained bleeding from surgical site

Leukemoid reactions are due to severe infections or inflammatory responses. To state that there is a leukemoid reaction, the Pts' WBC count must be ________________

greater than 25.0 X 10^9/L

Why is the duration of the half-life of IgG significant?

it binds with neonatal Fc receptor.

In hemolytic anemia, the significant morphological finding is ___________________.

microspherocytes

Osmolality measures

salt, urea, and glucose

In disseminated intravascular coagulation (DIC), the significant morphological findings are ___________.

schistocytes

Following a _________________ scattered acanthocytes, echinocytes, target cells, spherocytes, schistocytes, and Howell-Jolly bodies remain in the circulation.

splenectomy

In thalassemia minor, the significant morphological findings are ______________

target cells.

Which of the following reagents is often used to perform a direct antiglobulin test (DAT) to determine if either IgG or complement (or both) is attached to a patient's red cells? - Low-ionic strength solution (LISS) - Polyethylene glycol (PEG) - Anti-C3d - Polyspecific AHG

Polyspecific AHG

Hermaphroditic

Possessing both the male and the female reproductive organs in one body

Note the view of a peripheral blood smear in the photograph. Pictured are scattered acanthocytes, echinocytes, target cells, spherocytes, schistocytes and a Howell-Jolly Body. The condition in which each of these atypical RBC's may be found in the same patient's peripheral blood smear is:

Postsplenectomy syndrome

Which of the following contributes to specific gravity but does NOT contribute to osmolality?

Protein

Which of the following is a bronchodilator used to treat a 39-year-old male asthmatic patient? - Theophylline - Digoxin - Phenobarbital - Amitriptyline

Theophylline

The range between a drug's effective dose and its toxic dose is called?

Therapeutic window

Which type of lipoprotein transports the MAJORITY of cholesterol to cells for steroid hormone synthesis or cell membrane incorporation?

Low-density lipoproteins (LDL)

DTT is effective at denaturing the ___________ antigens.

Lutheran

In what disease states will howell-jolly bodies be seen?

Megaloblastic anemia, hypo-functioning spleen, splenectomy

Which of the following cells is the most common nucleated cell in normal adult bone marrow? - Myeloblast - Promyelocyte - Myelocyte - Metamyelocyte

Metamyelocyte

Which of the following best describes the benefits of the RPR or VDRL tests: - Diagnostic of active syphilis - Diagnostic of latent syphilis - Diagnostic of neuro-syphilis - Monitoring course of treatment

Monitoring course of treatment

What is the half-life of IgG?

18-23 days

All of the following are uses of nucleic acid tests for HIV infection, EXCEPT? - Monitor the effectiveness of antiretroviral therapy - Obtain a baseline value prior to the start of antiretroviral therapy - Diagnose HIV infection - Determine the degree of immune suppression caused by HIV

Determine the degree of immune suppression caused by HIV

The number of patients correctly diagnosed for the disease or not having the disease is defined as:

Efficiency

All of the following are known causes of aplastic anemia, EXCEPT? - Viral infections - Chemical agents - Enzyme deficiencies - Ionizing radiation

Enzyme deficiencies

After performing an antibody panel and a selected cell panel, you still can't rule out S and Fyb. It appears that the patient has anti-e and anti-Jkb, but they are only reacting microscopically. What technique would be the best way to strengthen the suspected antibodies?

Enzyme panel

_______________________ removes a large number of red blood cells from the patient and returns the patient's plasma and platelets along with compatible allogeneic donor red blood cells.

Erythrocytapheresis (RBC exchange)

Which of the following organisms is the most common cause of acute cystitis? - Escherichia coli - Klebsiella pneumoniae - Chlamydia trachomatis - Staphylococcus epidermidis

Escherichia coli

In which of the following conditions would you expect to find Howell-Jolly bodies? - Iron deficiency anemia - Splenomegaly - Diabetes - Megaloblastic anemia

Megaloblastic anemia

This antinuclear antibody (ANA) pattern is characterized by granular staining in the nuclei of the interphase cells (a). There is also an absence of staining in the chromosomal area of the metaphase mitotic cells (b). The slide is viewed using fluorescent microscopy. Which pattern is this?

Speckled

Which type of lipoprotein is the least dense?

chylomicrons

___________________causes harmless jaundice caused by hyperbilirubinemia and does not require treatment.

Gilbert's syndrome

________________________ has abnormal screening tests for platelet function; however, the platelet count and size are normal.

Glanzmann's thrombasthenia

A patient is being treated with gentamicin for a Gram-negative bacterial infection. The chemistry department has repeating peak and trough orders on the patient. Which of the following antibiotic classes does gentamicin belong to?

Aminoglycosides

Identify a characteristic of an organ-non specific disorder that distinguishes it from an organ specific disorder.

Lesions caused by deposition of antigen-antibody immune complexes

Which of the following is a genetic platelet disorder characterized by giant platelets, abnormal screening tests for platelet function and moderate to severe thrombocytopenia? - Glanzmann's thrombasthenia - Gray platelet syndrome - Delta storage pool disease - Bernard-Soulier syndrome

Bernard-Soulier syndrome

Which of the following tumor markers is associated with testicular cancer? - PSA - CEA - Beta hCG - CA-125

Beta hCG

A beta-hemolytic Streptococcus was isolated from a throat culture. It gave the following biochemical reactions: Bacitracin - Susceptible Bile esculin - Negative 6.5% NaCl - No growth CAMP - Negative SXT - Resistant What is the presumptive identification?

Beta hemolytic Streptococcus, Group A

Which of the following substances can cause a false positive result for blood on the urine chemical reagent strip? - Ascorbic acid - Bleach in the collecting bottle - High levels of nitrite - High specific gravity

Bleach in the collecting bottle

______________ is caused by Mycobacterium ulcerans, which would exhibit growth at 32oC.

Buruli's ulcer

In HbSS blood, an increased amount of which of the following surface antigens on young sickle cells (reticulocytes) may allow platelets to form a bridge between the reticulocytes and endothelial cells, ultimately leading to vaso-occlusion? - CD3 - CD4 - CD8 - CD36

CD36

The measurement of sodium and chloride in the sweat is the most useful test for the diagnosis of what condition/disease?

Cystic fibrosis

Infections with all of the following viruses could cause malignant disease, except: - Human papillomavirus (HPV) - Epstein-Barr Virus (EBV) - Human Herpesvirus 8 (HHV-8) - Cytomegalovirus (CMV)

Cytomegalovirus (CMV)

Which of the following patients is eligible for RhIG? - D-positive woman, 28 weeks gestation, no unexpected antibodies - D-negative woman, 28 weeks gestation, no unexpected antibodies - D-negative woman, 28 weeks gestation, immune anti-D present in serum - D-positive woman, 28 weeks gestation, anti-K present in serum

D-negative woman, 28 weeks gestation, no unexpected antibodies

Which of the following species or organisms is the most likely to cause mycotic keratitis (fungal infection of the cornea)?

Fusarium species

What are Howell-Jolly bodies composed of?

DNA

What are the expected results of the laboratory markers in iron deficiency anemia?

Decreased serum iron, increased transferrin, decreased ferritin, decreased percent saturation, and increased total iron-binding capacity.

Individuals with ____________ phenotype possess a low number of D antigen sites that can go undetected in routine serological testing.

Del

A Rh negative individual has produced an anti-D antibody. Which situation has the ability to stimulate this production of anti-D?

Delivering a Rh positive baby.

________________________ is a dense granule deficiency with a normal platelet count.

Delta storage pool disease

The Lutheran b antigen (Lub) is a high incidence antigen. A patient has developed an anti-Lub. All of the screening cells and antibody identification panel cells are positive at AHG. What can be used in testing so that the blood bank can determine if there are other clinically significant antibodies present in this patient?

Dithiothreitol (DTT)

Which condition is caused by deficient secretion of bilirubin into the bile canaliculi? - Gilbert's disease - Neonatal hyperbilirubinemia - Dubin-Johnson syndrome - Crigler-Najjar syndrome

Dubin-Johnson syndrome

______________________ is an autosomal recessive disorder that causes an increase of conjugated bilirubin without elevation of liver enzymes (ALT, AST). This condition is associated with a defect in the ability of hepatocytes to secrete conjugated bilirubin into the bile.

Dubin-Johnson syndrome

Conditions that produce elevated CSF protein levels include all of the following EXCEPT: - Meningitis - Multiple sclerosis - Hemorrhage - Fluid leak

Fluid leak

Which type of toxicology is primarily concerned with medical and legal consequences of exposure to chemicals and drugs?

Forensic toxicology

Agar plates on a positive blood culture are incubated for 48 hours and no growth is visible on the agar plates. The tech reviews the initial Gram stain from the blood culture bottle, which reveals tiny pleomorphic Gram-negative coccobacilli. What organism should the tech suspect and what should the tech do next?

Francisella tularensis; Sub blood culture bottle to a media with cysteine for optimal growth

A 56-year old female was taken to the emergency room in a coma by her employer's nurse. She had lost 35 pounds in 3 months; she was always thirsty; drinking a lot of water and running to the bathroom. The following are her laboratory results: What is the MOST likely cause of this patient's symptoms?

Insulin-dependent diabetes mellitus

The _______________________ is a procedure in which the red blood cells are lysed and the bodies of microfilariae are killed and straightened for better identification. The specimen is then centrifuged to concentrate it and the sediment is spread on a side and stained for review.

Knott technique

Which one of these Lewis blood group system phenotypes usually produces anti-Lea? - Le(a+b+) - Le(a+b-) - Le(a-b+) - Le(a-b-)

Le(a-b-)

The cells included in the composite image were found in the peripheral blood smear of a patient with the following results: total WBC of 21.5 x 109/L. Differential count: metamyelocytes 4 band neutrophils 16 segmented neutrophils 48 monocytes 6 eosinophils 1 basophils 1 lymphocytes 24 This hematologic picture is most consistent with:

Left shift

A 34-year-old female was seen in the dermatology clinic for some lesions on her fingers that had not responded to topical antimicrobial therapy. A tissue biopsy was sent for histological examination, routine culture, acid-fast bacilli (AFB) culture, and fungal culture. There was no growth on any culture, but AFB were seen in the histological preparations. The tissue culture for AFB had been incubated at both 35oC and 32oC, in liquid media and on media with hemoglobin added for several weeks. What is the most likely diagnosis of her skin lesions?

Leprosy

Enzyme-multiplied immunoassay techniques (EMIT) differ from all other types of enzyme immunoassays in that:

No separation of bound and free antigen is required.

Patterns of hydrolysis of tyrosine, xanthine, and casein are characteristics helpful in making species identifications within which genera?

Nocardia

The Sudan III stain is used to confirm the presence of:

Oval fat bodies

Which of the following might cause a false positive indirect antiglobulin test (IAT)? - Failure to adequately wash cells. - Delay in the addition of antiglobulin reagent. - Over-centrifugation - High concentration of IgG paraprotein in a patient's serum.

Over-centrifugation

Multiple ring forms in red blood cells are most frequently seen in which Plasmodium species infection?

P. falciparum

_______________________ is the study of how variations in the human genome affect a given individual's response to medications

Pharmacogenomics (Pharmacogenetics)

____________________ is the study of drug disposition in the body - how and when drugs enter the circulation, how long they stay there, and how they are eliminated.

Pharmacokinetics

What procedure utilizes leukapheresis to collect the buffy coat from whole blood?

Photopheresis

____________________ is the removal and retention of the plasma, with return of all cellular components to the patient.

Plasmapheresis

Which of the following tests require a 72-hour stool (fecal) collection?

Quantitative fecal fat

Which of the following statements is true regarding primary hemostatic process resulting from vascular damage? - Inhibition of platelet function by interaction with collagen. - Platelet adhesion through Weibel-Palade bodies. - Platelet aggregation through interaction of von Willebrand factor and glycoprotein IIb/IIIa. - Rapid and immediate vasoconstriction by contraction of smooth muscles.

Rapid and immediate vasoconstriction by contraction of smooth muscles.

All of the following are benefits of autologous donation EXCEPT: - Reduces exposure to infectious diseases - Readily available in case of an unexpected emergency - Reduces demand for homologous blood transfusions - Eliminates sensitization to cellular blood components

Readily available in case of an unexpected emergency

What would be the next step when an EDTA specimen had an automated platelet count of 61,000/mm3 and the platelets were surrounding the neutrophils on the differential?

Recollect a specimen for a platelet count without using EDTA

In the hookworm life cycle, which of the following is considered the noninfective larval form? - Rhabditiform - Filariform - Proglottids - Cercariae

Rhabditiform

A WBC differential count on CSF should be performed using the following technique:

Stained smear of a cyto-centrifuged specimen

Which of the following is LEAST likely to stimulate the production of reactive lymphocytes? The correct answer is highlighted below - Staphylococcus aureus - Cytomegalovirus (CMV) - Epstein-Barr virus - Toxoplasma gondii

Staphylococcus aureus

The light tan, delicate, cottony colony that covers the entire surface of the SABHI agar plate grew in 3 days when incubated at 30° C as illustrated in the top photograph. This morphology is characteristic of one of the Zygomycetes. As the colony morphology is non-selective, the identification of this isolate is made by observing the characteristic fruiting head as illustrated in the bottom lactophenol blue-stained photomicrograph. From these observations, select the name of this isolate from the list of multiple choices. - Mucor species - Rhizopus species - Syncephalastrum species - Cunninghamella species

Syncephalastrum species

Contact dermatitis is mediated by:

T lymphocytes (and macrophages)

A mother's serologic results are shown above. Her newborn types as group A Rh positive with a (1+) positive direct antiglobulin test (DAT). Which of the following investigative tests would be most useful to resolve the cause of the positive DAT and should be done FIRST? - Test an eluate prepared from newborn's red cells against an antibody identification panel by IAT. - Test newborn's plasma against group A1 red cells and group O antibody screen cells by IAT. - Test newborn's plasma against mother's red cells by IAT. - Test newborn's plasma against father's red cells by IAT.

Test newborn's plasma against group A1 red cells and group O antibody screen cells by IAT.

The qualitative differences between A1 and A2 phenotypes includes all of the following EXCEPT: - The formation of anti-A1 in A subgroups. - The amount of transferase enzymes. - The length of the precursor oligosaccharide chains. - The lack of agglutination of patient red cells with anti-A reagent.

The lack of agglutination of patient red cells with anti-A reagent.

Which of the following best describes the methodology for FISH? -Uses directly labeled fluorescent nucleotides or probes with reporter molecules that are indirectly detected by fluorescent antibodies or affinity molecules - Signal amplification test that uses signal amplification and alkaline phosphatase - Target amplification test that uses thermal cycling and DNA polymerase - Target amplification test using thermal cycling and DNA ligase

Uses directly labeled fluorescent nucleotides or probes with reporter molecules that are indirectly detected by fluorescent antibodies or affinity molecules

What causes polyacrylamide gels to have greater resolution of proteins than agarose gels? The correct answer is highlighted below - Polysaccharide composition - Electroendosmosis - Transparency - Varying pore size in each polyacrylamide layer

Varying pore size in each polyacrylamide layer

A patient presents to the emergency room with severe headaches, nausea, and vomiting. CSF chemistry results are as follows: Protein - 74 mg/dL (15-45 mg/dL) Glucose - 53 mg/dL (40-85 mg/dL) Based on the patient's complaints and the above laboratory results what is the most probable condition?

Viral meningitis

Most disorders associated with a primary immunodeficiency are _________ disorders.

B-Cell disorders

What percentage of glycerol is most commonly used when freezing red blood cell units?

40%

There is NO anemia at birth in ___________ HDFN

ABO

There is NO elevated bilirubin at birth in ___________ HDFN

ABO

Formation of which of the following forms of poikilocytosis listed below is associated with absence of beta-lipoproteins (abetalipoproteinemia)?

Acanthocytes

Which of the following characteristics of hemolytic disease of the fetus and newborn (HDFN) is NOT different for ABO and Rh HDFN? Disease predicted in titers Anemia at birth Antibody is IgG Bilirubin at birth

Antibody is IgG

________________ typically causes otitis externa and can also be associated with sinusitis.

Aspergillus niger

A patient was admitted to the hospital for fever, chills, weight loss, headaches, and fatigue. The patient mentioned that he had cut his hand while hunting wild boar a couple of weeks ago. Blood cultures were received in the microbiology laboratory and several days later a bone marrow specimen on the patient was received. The blood culture was positive after 5 days and the bone marrow grew a small, convex, smooth colony after 48 hours on sheep blood and chocolate agar. A gram stain was performed and demonstrated small Gram-negative coccobacilli organisms. Which of the following organisms is the cause of infection for this patient? - Bacillus anthracis - Brucella suis - Acinetobacter species - Moraxella species

Brucella suis

Which of the following genotypes is found with the highest frequency in the Caucasian population?

CDe/ce

8-Hydroxyquinoline and Ortho-Cresolphthalein complexone (CPC) reagent is commonly used in the determination of:

Calcium

A Gram stain of drainage from an open wound revealed gram-positive bacilli with spores. This description would commonly rule out which one of the following organisms? (Choose the BEST response.)

Clostridium perfringens The presence of spores virtually rules out Clostridium perfringens. While the organism does produce spores, they are rarely seen in clinical infections.

Although care should be taken when working with all fungus cultures in the laboratory, personnel are particularly prone to develop laboratory acquired infections from the inhalation of airborne species of:

Coccidioides immitis

________________ uses the results from animal experiments to predict what level of exposure will cause harm in humans.

Descriptive toxicology

In the upper image is a short, thin, thread-like adult worm. The lower image is the scolex of this worm, with a protruding armed scolex and a row of hooklets. Also known as the "dwarf tapeworm", what is this cestode that also commonly infects children?

Hymenolepis nana

Patients with which of the following conditions would benefit most from washed red cells:

IgA deficiency with anti-IgA

___________ has a half-life of 18-23 days; it is important for B-cell activation and/or regulation.

IgD

_________ has a half-life of 5-6 days; it participates in an immediate hypersensitivity reaction.

IgE

The Knott technique is used to identify:

Loa loa

Erythema migrans, spirochetemia, and chronic arthritis are three stages in the progress of:

Lyme disease

A patient has a history of repeated spontaneous abortion. Coagulation studies reveal an elevated APTT, normal PT, normal platelet function, and normal thrombin time. Schistocytes were seen on the peripheral blood smear. Which test should be performed to determine if the patient has lupus anticoagulant?

Platelet neutralization test

A patient, who recently received a transfusion of three units of red cells, is DAT-positive with an IgG specificity. What would be the best method to identify the patient's phenotype?

Polymerase chain reaction-based assay

There is anemia at birth in ___________ HDFN

Rh

There is elevated bilirubin at birth in ___________ HDFN

Rh

___________ HDFN is predicted in titers

Rh HDFN

____________________ is commonly associated with sinusitis.

Scedosporium apiospermum

All of the adult forms of the following worms are hermaphroditic, EXCEPT: - Hymenolepis - Taenia - Schistosoma - Clonorchis

Schistosoma

Which of the following statements is TRUE for specific gravity measured by the urine chemical reagent strip method?

The urine chemical reagent strip method is not affected by the presence of x-ray contrast media in the urine specimen.

In alkaline hemoglobin electrophoresis, band A is closest to the _____________

anode

Which of the following can lower the amount of current needed to cause electricity-induced injury? - Ground wires - Wet skin - More carbon dioxide in the air - Dry skin

Wet skin

A reaction is in ____________ kinetics when the reaction rate depends only on enzyme concentration.

Zero-order

The gene loci for the alpha-globin chains are adjacent to the locus for which other globin chain? Beta Delta Epsilon Zeta

Zeta