MediaLab Practice
A manual white blood cell count was performed by the hematology technologist. The cell counts for each of two sides was 38 and 42 respectively. All nine large squares were counted on each side. The dilution for this kit was pre-measured at 1:10. What should the technologist report as the white cell count?
0.44 x 109/L; (40 x 10) / (9 x 1mm2 x 0.1mm) = 444.4/mm3 (can be converted to 0.44 x 109/L)
Which Gram positive bacilli will show a positive result for urease?
Actinomyces naeslundii
At a minimum, how frequently should an ocular micrometer be calibrated?
After major cleaning of the microscope or replacing objectives and as part of annual maintenance.
Which Aspergillus species has been recovered from the cornea?
Aspergillus fumigatus
Which of the following D variants has the best likelihood to receive D-positive RBCs without any adverse effects?
C in Trans to RHD
Which cardiac biomarker is a regulator of myocyte contraction?
CTnT
Which of the following is least likely to interfere with the measurement of hemoglobin?
Cold agglutinin
Cystine-tellurite blood agar is recommended for the isolation of which organism?
Corynebacterium diphtheriae
he measurement of sodium and chloride in the sweat is the most useful test for the diagnosis of what condition/disease?
Cystic fibrosis
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.
A two-year old male patient has the following hemogram results: Hgb = 6.7g/dL Hct = 20% Platelets = 355 x 109/L RBC = 3.0 x1012/L WBC = 8.75 x 109/L Differential = 6% eos, 20% segs, 68% lymphs, 6% monos
Dietary iron deficiency
The laboratory test most commonly used to establish a definitive diagnosis of primary syphilis is:
Direct fluorescent antibody test
In which of the following cases should Rh Immune Globulin (RhIG) be given?
Ectopic pregnancy
Which one of the following organisms is typically urease negative:
Escherichia
All of the following are Lancefield carbohydrate antigens found on beta-hemolytic Streptococcus species. All of the following antigens are found on organisms from the Streptococcus anginosus group EXCEPT?
F
An isolated crenated erythrocyte with spicules is seen on an otherwise normocytic normochromic peripheral blood smear. Which of the following statements is true?
Finding is most likely an artifact caused by poor smear preparation
During which stage of a syphilis infection will a patient develop the painless chancre?
First stage
Which of these methods measures fetal hemoglobin or D positive red cells or both to evaluate fetomaternal hemorrhage?
Flow cytometry
All of the following statements about fluorometry are true, EXCEPT:
Fluorescence is indirectly proportional to the analyte being measured.
Which term describes the cellular morphology of bacteria with a pointed end?
Fusiform
All of the following represent a 2 week temporary deferral from donating blood or blood products EXCEPT:
German measles (rubella) vaccine
All of the following would be suitable for the identification of bacterial antigens, EXCEPT?
Gram Stain Reactions; -Gram stain reactions will not help to identify bacterial antigens since it cannot help bind to cell membrane antigens.
The gel electrophoresis pattern for hemoglobin S (HbS) shows which of the following migration patterns?
HbS migrates with HbD in alkaline and alone in acid electrophoresis.
A new tech has a presumptive Salmonella 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 one of the physical examination results below may be cause to reject a donor from blood donation?
Hemoglobin of 12.0 g/dL (The hemoglobin level of a donor should be greater than or equal to 12.5 g/dL.)
An electrophoretic separation of lactate dehydrogenase isoenzyme that demonstrates elevation in LD-1 greater than LD-2 could be indicative of:
Hemolysis
The autohemolysis test is MOST useful in the diagnosis of which condition?
Hereditary spherocytosis
Which genetic description will NOT contain Bart's hemoglobin at birth ?
Heterozygous alpha thalassemia-2
Which test is considered a more reliable method of monitoring long-term diabetes control?
Hgb A1C
The primary mechanism responsible for glomerular filtration is: The correct answer is highlighted below
Hydrostatic differential in glomerular tufts
How does hydroxyurea aid in the treatment of sickle cell disease?
Induces increased production of HbF
Why might serum ferritin (SF) alone be considered a less than optimal screening test for hereditary hemochromatosis (HH)?
It is an acute phase reactant that is frequently elevated in a variety of clinical conditions.
Which one of the following is a TRUE statement concerning alkaline phosphatase?
It is increased in obstructive jaundice
Which of the following antigens are well developed on fetal cells?
Kell
What is the probable identity of an organism isolated from a wound culture that demonstrates the following test results? Phenylalanine Deaminase = negative TSI = A/A gas Citrate = positive Lysine = positive SIM = negative/negative/negative Urea = weakly positive
Klebsiella pneumoniae
Which of the following tests on amniotic fluid would be included when assessing fetal lung maturity:
L/S ratio; The lecithin/sphingomyelin ratio is determined by examining the amniotic fluid of a pregnant mother. Because amniotic fluid is continuously swallowed or inhaled and then replaced or exhaled in uterus the ratio can be measured to determine how much surfactant is in the fetal lungs.
From the choices listed below, which organism is classified as an aerotolerant anaerobe?
Lactobacillus species
In the hookworm life cycle, which of the following is considered the noninfective larval form?
Rhabditiform
Which yeast species is most likely the colony morphology as seen in the bottom right image
Rhodotorula species
To ensure quality within the preanalytical phase of laboratory testing, quality assurance activities includes monitoring all of the following preanalytical variables EXCEPT:
Selection of reference materials used for validation purposes; - Selection and evaluation of reference materials are factors that can impact the analytical phase of clinical laboratory testing. Analytical variables include calibration of balances, temperature monitoring (e.g. refrigerators, freezers, water baths), and water quality.
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.
Speckled
The body of an adult tapeworm is known as the:
Strobila
A tech is testing a sorbitol negative isolate for possible E.coli O157: H7 from the MacConkey with sorbitol agar plate. The biochemical identification proves the organism is E.coli. Serological testing for the O157 somatic antigen is positive. Serological testing for the H7 flagellar antigen is negative. Quality control for all serological testing passed. What should the tech do next?
Subculture the organism to motility medium for repeat H7 serological testing
When a Specked Nuclear Antibody (ANA) pattern is observed, what follow-up test for antibodies related to Systemic Lupus Erythematosus (SLE) is not beneficial?
Testing for antibodies to U1RNP+ and dcSSc
When collecting a urine specimen for workplace drug testing, which of the following situations may indicate that the specimen has been tampered with or adulterated?
The specific gravity test result is 1.001
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.
Which one of the following statements concerning Vitamin D is correct?
Vitamin D acts as a hormone in calcium regulation.
Which marker is most useful for the detection of gestational trophoblastic disease?
hCG (human chorionic gonadotropin)
In the steps involved in performing a bone marrow differential what objective is used and how many cells must be counted?
100x (oil), 200 cells
A serum ferritin above what level would be suggestive of iron overload and possibly hereditary hemochromatosis (HH) in a pre-menopausal woman?
200 ng/mL
How many standard deviations (SD) above and below the mean is accepted as being an appropriate control limit range on a control chart utilizing the Westgard rules:
3SD
If parents have the blood group genotypes AA and BO, what is the possibility of having a child with a blood type of A?
50%
Adult (normal) Hemoglobin is made up of the following composition:
>95% HbA, <3.5% HbA2, <1-2% HbF
From the IgG molecule illustration, which region is the heavy chain?
A = Heavy chain
A hepatic function panel A consists of which of the following tests?
AST, ALT, Alkaline Phosphatase, Total Protein, Albumin, Total Bilirubin, Direct Bilirubin;
Which of the following blood tests is used in the determination of prostate cancer?
Acid phosphatase
ll of the following are factors that will affect migration in gel electrophoresis, EXCEPT?
Amount of light present
Which of the following blood tests is used to determine acute pancreatitis?
Amylase; Amylase test helps to determine acute pancreatitis. It should be collected in a gel-barrier serum tube (red or gold top). Hemolysis and lipemia should be avoided. Serum should be separated from cells immediately and refrigerated for storage.
On a quiet evening shift at a small hospital, you encounter a specimen with a positive antibody screen. As per your current laboratory protocol, you check for agglutination at the immediate spin phase of testing; and then again at the antihuman gloubulin (AHG) phase of 37°C. According to your laboratory guidelines, a single homozygous cell may be used to rule out an antibody. Based on the following 3-cell screen performed by tube, which of the following clinically significant antibodies are you unable to rule out?
Anti-Fya, -C, -Lub
If detected in antibody screen testing, which of the following antibodies is NOT considered clinically significant in prenatal patients?
Anti-Leb
Homogentisic acid in urine will cause urine to be which of the following colors?
Brown/black
Error rates in the laboratory are estimated at what rate?
Between 1:164 to 1:8300 results.
To assess drug concentrations during the trough phase:
Blood should be drawnimmediately before the next dose is given.
This species of Candida accounts for around 20 percent of urinary yeast isolates.
Candida glabrata
Which of the following statement is INCORRECT regarding the bone marrow biopsy specimen?
Cellular morphologic detail can be determined.
Which antinuclear antibody (ANA) pattern is seen in the image on the right, which represents the result of an ANA test viewed using fluorescent microscopy?
Centromere
Which of the following clinical laboratory departments performs the most tests?
Chemistry
A variety of additives are used in blood collection tubes. Which of the following additives prevents clotting by inhibiting thrombin and thromboplastin?
Lithium or sodium heparin
An important metallic activator of alkaline phosphatase and creatine kinase is:
Magnesium
Which of the following best describes the benefits of the RPR or VDRL tests:
Monitoring course of treatment
Which of the following organisms are aerobic, Gram negative diplococci that do not ferment sugars and is DNAse positive?
Moraxella Catarrhalis
You are collecting a blood specimen to be used for forensic (legal) alcohol testing. Which of the following must be done before you can start the specimen collection process?
Must inform the patient that the blood about to be collected is for alcohol testing.
Observe the bone marrow sample in the image to the right. All of the descriptors below apply EXCEPT?
Myeloid precursors predominant
Proteins in a buffer that sets the pH at 8.6 will become ___________ charged and migrate to the ____________.
Negatively; Anode
A 41-year-old man is admitted to the hospital complaining of a decreased frequency of urination, a constant bloated feeling, weight gain, and mild edema of the ankles and eyes. Urinalysis results are as follows: Color: pale yellow Microscopic Results: Clarity: clear RBCs 0-2 pH: 5.0 WBCs 0-2 Sp. Gravity 1.010 Casts: 2-5 hyaline, 0 - 3 fatty casts, 0 - 2 waxy casts Glucose: 2+Few transitional epithelial cells Ketones: negativeFew oval fat bodies Protein- 3+Blood: moderate Bilirubin: negative Bacteria: negative Urobilinogen: normal Nitrate: negative**A large amount of white foam was noted.
Nephrotic syndrome
Which of the following organisms appear Gram-positive when using the Gram Stain?
Peptostreptococcus anaerobius
What procedure utilizes leukapheresis to collect the buffy coat from whole blood?
Photopheresis
In which developmental stage do red blood cells begin forming hemoglobin in amounts large enough to be visualized on a Wright-stained bone marrow aspirate smear?
Polychromatic normoblast
This image represents a field of red blood cells (RBCs) stained using a supravital stain. How would these cells appear if viewed on a Wright-stained smear?
Polychromatophilic RBCs
Which finding best distinguishes immune hemolytic anemia from other hemolytic anemias?
Positive DAT
Illustrated in the photograph is the 4-day slow growth of colonies recovered on an anaerobic culture. Note the small size of the colonies growing on anaerobic blood agar, distinctive for brown-black pigmentation surrounded by a wide zone of beta hemolysis. Gram stain revealed small, gram-negative coccobacilli. Most strains are biochemically inactive, although glucose and lactose fermentation are positive (saccharolytic). A common source would be from an infection of the oral cavity or from an infected human bite wound. From these observations, select from the multiple choices the identification of this isolate.
Prevotella melaninogenica
A specimen drawn from an indwelling catheter that was contaminated by heparin would be indicated by:
Prolonged aPTT and normal reptilase time test; - Heparin contamination is characterized by an elevation in the aPTT test and can also cause an increased PT test as well. Reptilase time tests are used to eliminate the effects of heparin contamination as the reagents and method are resistant to the effects of antithrombin III, unlike the PT and aPTT tests.
Which of the following tests require a 72-hour stool (fecal) collection?
Quantitative fecal fat;
Which adsorption technique removes cold (IgM) antibodies, particularly anti-I specificities?
Rabbit erythrocyte stroma (RESt)
Which of the following conditions would argue in favor of therapeutic drug monitoring (TDM) for a given drug?
The drug is given chronically.
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:
The intended response here is left shift. A left shift is an increase in immature granulocytes, primarily band neutrophils and metamyelocytes. Other findings associated with a left shift are toxic granulation and Döhle inclusion bodies in the neutrophils.
The qualitative differences between A1 and A2 phenotypes includes all of the following EXCEPT:
The lack of agglutination of patient red cells with anti-A reagent.
The type of hypersensitivity reaction associated with macrophage activation, cytokine-mediated inflammation is:
Type IV
Which purine base is found in RNA and not in DNA?
Uracil
A tech is working with a small, Gram-negative coccobacillus that may be Brucella spp. Which of the following tests could the tech use to rule out this organism?
Urease negative
A blood sample is left on a phlebotomy tray for four hours before it is delivered to the laboratory. Which group of tests could still be performed?
Uric acid, BUN, creatinine. Uric acid, BUN, and creatinine are not affected by the delay in testing.
