RECALLS page 56-74 Flashcards
(311 cards)
1
Q
VRE isolated in the lab, what do you do?
A
Report to infection control officer
2
Q
Enterococcus isolated from CSF, which antibiotic should be used to treat?
A
Ampicillin
3
Q
Zone of inhibition is high, what is the reason?
A
Inoculum size low
4
Q
Zone of inhibition is low, what is the reason?
A
Inoculum size high
5
Q
When do you measure the pH of the media?
A
After rehydration, before autoclaving
6
Q
Which organism is associated with burn patients?
A
Pseudomonas aeruginosa
7
Q
What is the most cost-effective method for identifying Streptococcus pneumoniae?
A
Gram’s stain
8
Q
What is a computerized data entry system called?
A
Informatics
9
Q
Oxacillin sensitivity zone is 20 mm. What should you do?
A
Do cefoxitin sensitivity
10
Q
How to differentiate Vibrio, Aeromonas, and Plesiomonas?
A
Salt tolerance
11
Q
Which medium is used to differentiate Klebsiella pneumoniae and Klebsiella oxytoca for indole?
A
Blood agar
12
Q
Which media is used to isolate the organism causing cystic fibrosis?
A
Rogen Lowe with O₂
13
Q
D+C+E+c+e+, what is the possible genotype?
A
R1R2
14
Q
D+C−E+c+e+, what is the possible genotype?
A
R2r
15
Q
If Anti-E+, Anti-Fya+, and Anti-M+ are detected, which unit is suitable?
A
E−, Fya−, M+ (i.e., negative for E and Fya, positive for M)
16
Q
What differentiates IgG from IgM?
A
Temperature (IgM reacts best at cold temp, IgG at 37°C)
17
Q
Which of the following is expected in polycythemia vera?
A
Platelet high, LAP score high
18
Q
If both PT and PTT are high, which factors might be deficient?
A
Factors II, V, and X
19
Q
INR is 5.2. Which blood component should be transfused?
A
Fresh Frozen Plasma (FFP)
20
Q
In immunocytochemistry, what step is required to remove background staining?
A
Peroxide block (to eliminate endogenous peroxidase activity)
21
Q
What does it mean when there is no band in control or test line in an immunochromatographic spot test?
A
Invalid test (likely procedural error or defective strip)
22
Q
In reticulin staining, what removes unreduced silver?
A
Sodium thiosulfate
23
Q
Which stain is used to demonstrate increased collagen in the liver?
A
Masson’s Trichrome
24
Q
Which stain demonstrates neutral mucin?
A
PAS (Periodic Acid–Schiff)
25
What causes pale eosin staining in H&E?
High pH
26
What is used to differentiate bacteria from debris in Gram stain?
Stain with acridine orange
27
Which of the following is related to specificity?
The ability of a test to correctly identify those without the disease (true negatives)
28
What is affected in a systematic error?
Mean
29
Which factor is activated by Factor XIa?
Factor IX
30
What is the appropriate equipment for sputum processing?
Biosafety cabinet
31
What causes sections to fall off slides during reticulin staining?
Alkalinity of the solution
32
What is true about Bacteroides fragilis?
Endogenous infection from mouth and gut flora
33
Platelets clumping with neutrophils on smear—what anticoagulant can prevent this?
Citrate
34
What does a left shift in the RBC histogram indicate?
Microcytosis
35
In hereditary spherocytosis, which hematological parameter is affected?
MCV (often normal or decreased, but increased MCHC is more specific)
36
Which of the following is not detected using Romanowsky stain?
Heinz bodies
37
How is WBC count calculated?
WBC × dilution factor ÷ volume of area counted (exact formula varies with method)
38
How is corrected WBC count calculated (in presence of NRBCs)?
(WBC count × 100) ÷ (NRBCs + 100)
39
How is MCH calculated?
(Hemoglobin × 10) ÷ RBC count
40
How is absolute reticulocyte count calculated?
Reticulocyte % × RBC count ÷ 100
41
What is neutropenia?
A decreased absolute neutrophil count (ANC) below reference interval (often <1.5 × 10⁹/L)
42
A 1-day-old child has neutropenia without blasts reported by the Coulter counter. What is the next step?
Review the smear manually
43
You detect Plasmodium falciparum. What should be done next?
Perform % parasitemia count
44
You detect Plasmodium vivax. What is the next step?
Perform % parasitemia count
45
In a PCR cycle, no product is detected colorimetrically after 30 cycles. What would you do?
Report negative
46
In a PCR cycle, no product is detected colorimetrically after 20 cycles. What is your next step?
Do more cycles
47
What would you do if the potassium value of a patient is 6.5 mmol/L?
Immediately call the physician
48
A friend told you to do a STAT test for an instrument you’re not familiar with. What would you do?
Report to the supervisor
49
Which antiseptic is appropriate for blood alcohol collection?
Soap and water
50
Wristband is not with the patient—how would you identify them?
Ask the nurse
51
Which tissue requires 2-week fixation?
a. Brain
52
For which of the following patients can you reject specimen collection?
c. Aggressive
53
What information is required with the full name during aliquot transport?
a. Accession number
54
How do you track a urine sample during the culture process?
b. Accession number
55
Urine result: WBC <2–4, RBC <0–2, moderate blood reaction. What does this indicate?
a. Hemoglobinuria
56
If a urine specimen for culture is left at room temperature for 24 hours, what is expected?
c. Normal flora overgrows
57
How do you transport a specimen for Neisseria gonorrhoeae?
b. Chocolate plate with CO₂
58
A 1/10 diluted urine specimen with 0.01 mL loop yields 86 colonies. What is the CFU/mL?
8.6 × 10⁵ CFU/mL
59
What would you do if there’s saline residue in the automatic crossmatch machine?
Flush the tube/kube
60
Gram-negative intracellular diplococci isolated from sputum is likely:
c. Moraxella catarrhalis
61
Urea is normal and creatinine is high in a new healthy patient. What should you do?
b. Repeat the test
62
What is the effect of saline in the zone phenomenon?
Reduces the reaction
63
What is the reducer in the Gordon and Sweet method?
10% Formalin
64
What is the reducer in the Von Kossa method?
Hydroquinone (standard answer; confirm with lab SOPs)
65
Ice crystal artifact in histology is due to:
Slow freezing
66
Which ABO group has the greatest amount of immune hemagglutinins (IH)?
Group O
67
Which stain differentiates myeloblasts from monoblasts?
NSE (Non-specific esterase)
68
Glucose mean = 5.4 mmol/L, SD = 0.1 mmol/L. If result is 5.1 mmol/L, what should you do?
a. Reject the result (as it is beyond ±3 SD)
69
How is the anion gap calculated?
Na⁺ – (Cl⁻ + HCO₃⁻)
70
What is the formula for creatinine clearance?
(Urine creatinine × Urine volume) / (Plasma creatinine × Time in minutes)
71
What to do if the urine sample for osmolality is turbid?
a. Centrifuge
72
What is the method for urine osmolality measurement by freezing point?
Freezing point depression method
73
Which plasma type is acceptable for magnesium determination?
b. Heparin
74
For a nitric acid spill, which PPE is required?
a. Rubber gloves
75
How should you handle a large spill of flammable liquid?
b. Report to the maintenance department
76
Which chemical requires low-gravity fume hood storage?
a. Nitric acid
77
Which antibody is related to urticarial transfusion reactions?
IgE
78
What should you do if the tube coagulase test is negative after 24 hours at 37°C?
Re-incubate at room temperature (RT) for an additional 24 hours
79
What should you do if you get a positive result with the latex coagulase test?
b. Do tube coagulase test
80
Under which act is the employer responsible for the employee’s safety?
Occupational Health and Safety Act (OHSA) (depends on jurisdiction; in Canada, it’s OHSA)
81
What causes muscle to stain pale pink in Masson’s Trichrome?
Inadequate use of phosphomolybdic acid
82
You get multiple bands after running PCR. What should be done?
Design a more specific primer
83
What is the ESR test used for?
To detect inflammation or monitor inflammatory diseases such as infections, autoimmune disorders, and cancers
84
ESR is used for detecting what type of condition?
Detecting a chronic disease (e.g., autoimmune disorders, chronic infections)
85
Which of the following is an example of in vitro sensitization?
a) DAT (Direct Antiglobulin Test)
86
A sample was drawn and refrigerated before centrifugation. Serum was separated the next day and tested for cold agglutinins. What is the effect on the test?
b) Falsely decreased
87
Leukocyte esterase is negative on a urine dipstick but 10–20 WBCs are seen on microscopy. What is the likely cause?
High glucose concentration (can inhibit the leukocyte esterase reaction)
88
What is the correct order of donning PPE?
Gown → Mask/Respirator → Goggles/Face shield → Gloves
89
A specimen clotted and was refrigerated overnight. A cold agglutinin titre was performed the next day. What is the expected result?
Falsely low
90
What is not removed from the red cell button after washing prior to testing?
Wash saline
91
Urine leukocytes negative on dipstick, but WBC 20–50/hpf seen microscopically. What is the likely cause?
High glucose concentration
92
What should a technologist do at a workshop during accreditation?
Learn about new analyzers and stay within laboratory practice scope
93
Urine leukocytes and nitrites are negative. What should you do?
Report as normal
94
Which organism shows bipolar staining?
Yersinia pestis
95
In Masson’s Trichrome, blue staining with black nuclei and pale red cytoplasm—what needs to be done?
Adjust dye proportions or staining time
96
APTT is 90s, INR is 1.1, and patient has no bleeding history or anticoagulants. What factor deficiency is likely?
Factor XII (12)
97
Which factor is activated when APTT reagent is added?
Factor XII
98
What differentiates primary from secondary fibrinolysis?
Increased D-dimers and decreased fibrinogen in secondary fibrinolysis
99
Which fixative dehydrates to fix proteins?
Ethanol
100
Hemoglobin is consistently reading 180 g/L. What could be the cause?
Expired diluent or blocked aperture
101
Leukemic anemia with 75% blasts. What helps differentiate the type?
Presence of Auer rods
102
What is expected in hyperparathyroidism?
High calcium and low phosphate
103
A patient has Na⁺: 140, Cl⁻: 118, K⁺ >8. What is the likely cause?
Electrolyte imbalance (e.g., sample hemolysis or renal failure)
104
Important step in immunofluorescence?
Proper antibody incubation and thorough washing
105
Tissue received with labeled requisition but the sample is unlabeled. What should be done?
Resolve labeling issue before proceeding
106
Given SD = 0.1 and Mean = 5, what percentage exceeds 5.01?
2.5%
107
Blood culture machine is not working. What can you do to accelerate microorganism detection?
Perform direct Gram stain
108
Urine sample with <10⁵ CFU/L. What will help in detection?
Fluorescence with acridine orange
109
What happens in competitive immunoassay if incubation is decreased?
False decrease in result
110
What is used to assess cancerous margin lesions?
Histopathologic margin evaluation
111
QC1 = +2.25SD, QC2 = –1.95SD, Na⁺ = 140 mmol/L. What should you do?
Recalibrate analyzer before reporting
112
Coffin-shaped crystals in alkaline urine indicate?
Triple phosphate crystals
113
Why do technologists perform one annual blood draw?
Process improvement and competency validation
114
PCR electrophoresis bands did not move far from application point. What is the likely cause?
Low ionic strength or low voltage during electrophoresis
115
Which antibody is least likely to be detected at Immediate Spin (IS) phase?
Anti-Jka
116
Which of the following is an example of in vitro sensitization?
DAT (Direct Antiglobulin Test)
117
A patient develops urticaria during transfusion. What is the likely cause?
Allergic reaction
118
What happens if the anti-roll device in a cryostat is not properly adjusted?
Tissue sections will vary in thickness (thin and thick sections)
119
What antibody is responsible for anaphylactic transfusion reactions?
IgA (in IgA-deficient patients)
120
What color does Mycobacterium leprae stain in Kinyoun stain after carbol fuchsin?
Red
121
Mom: O Rh-negative with anti-D and anti-Le, Baby: A Rh-positive, DAT positive. What is the explanation?
Anti-D coating baby’s red cells
122
A Hemophilia A patient is bleeding severely. What is the treatment of choice?
Factor VIII concentrate
123
Haemophilus influenzae with beta-lactamase—what is its ampicillin susceptibility?
Resistant
124
QC: S. aureus catalase negative, Streptococcus catalase positive. What should you do?
Repeat QC with proper organisms
125
When should you refuse a blood draw?
When the patient is aggressive
126
What is the first thing to do when you arrive at the patient’s bedside?
Identify the patient
127
What is a disadvantage of POCT (Point of Care Testing)?
It is expensive
128
How should conflict in the lab be addressed?
Through collaboration
129
What does the Ct (cycle threshold) value represent in real-time PCR?
The cycle number at which fluorescence exceeds background threshold
130
What should be considered in laboratory budget planning?
Sick time, accident reports, shift scheduling
131
A unit of frozen plasma is delivered without dry ice. What should be done?
Discard the unit
132
Pale cytoplasmic staining in H&E stain is due to?
High pH of eosin
133
What chemical should be stored grounded?
Glacial acetic acid
134
Platelet satellitism around neutrophils is observed. What should be done?
Recollect using sodium citrate as anticoagulant
135
Which organism is commonly isolated from cystic fibrosis patients?
Pseudomonas aeruginosa
136
An unlabelled blood sample is received. What should be done?
Recollect the sample
137
A smaller zone of inhibition is noted for 2 days in a row. What is the best explanation?
Expired antibiotic discs
138
Anaerobic jar methylene blue indicator is still blue after 30 minutes. What should be done?
Allow more time for anaerobic conditions to develop
139
Condensation in the anaerobic jar is present, but the methylene blue indicator is still blue after 48 hours. What is the issue?
Lid gasket is defective
140
Tissue received in formalin for culture. What should be done?
Reject the specimen
141
What are Levy-Jennings charts used for?
Quality control interpretation
142
Which RBC inclusion contains DNA?
Howell-Jolly bodies
143
What is the correct technique when inoculating urine culture?
Use calibrated loop vertically
144
Von Kossa stained slide did not stain well. What is the cause?
Inadequate exposure to light
145
A plasma donor unit arrives without dry ice. What should you do?
Reject the unit
146
Anti-Lea antibody is detected in a pregnant woman. What should be done?
Report the finding (Anti-Lea is not clinically significant in pregnancy)
147
In the Coombs test, no agglutination is observed after adding AHG and centrifugation. What should you do?
Add Coombs control cells to confirm AHG activity
148
In phenotyping, what type of cell should be used?
Heterozygous cells with weakest antigen expression
149
How often should blood bank refrigerators be monitored?
Every 4 hours (or continuously with alarmed systems)
150
An increase in dialysis patients will increase workload in which departments?
Chemistry and Hematology
151
Who should be prioritized for transfusion?
Emergency amputation patient
152
What must be done before releasing blood for transfusion?
Perform a visual inspection of the unit
153
How long should transfusion investigation samples be stored?
7 days at refrigerator temperature
154
What is the optimal long-term storage temperature for AHG reagent?
4°C
155
Which disinfectant is ineffective against fungi?
Ethanol (kills bacteria but not all fungi)
156
Alpha-hemolytic, catalase-negative, optochin-resistant, bile-solubility-positive organism is most likely:
Streptococcus pneumoniae
157
What test should follow a slide coagulase test?
Tube coagulase test
158
What biosafety cabinet is required for handling infectious aerosols?
BSC Class II
159
What is the acceptable time frame for transporting anaerobic surgical specimens?
Less than 2 hours
160
What can cause a larger zone of inhibition in susceptibility testing?
Decreased agar depth (thinner media)
161
What disinfectant should be used for a Mycobacterium tuberculosis (MTB) spill?
70–90% alcohol
162
What should be done before transporting Bacillus anthracis?
Notify the receiving lab and use proper containment
163
Swarming observed on a susceptibility test plate—what should be done?
Measure the zone as usual
164
Which organism is commonly isolated from burn patients?
Pseudomonas aeruginosa
165
Common cause of pharyngitis?
Group A Streptococcus
166
A candle jar shows blue indicator after 24 hours. What does this mean?
There is a leak in the jar
167
Contamination on blood agar plate may lead to what result?
False positive culture
168
What is the most economical method for bacterial workup?
Isolation and identification
169
What is used for DNase QC testing?
DNase-positive and negative control organisms
170
What is the causative organism of whooping cough?
Bordetella pertussis
171
You are given three organisms with their antibiotics; Enterococcus is listed as sensitive to vancomycin. What should you do?
Report as vancomycin-sensitive
172
A 24-hour urine is sent for both culture and sodium testing. What is the correct action?
Reject for culture; accept for sodium
173
What should be done with a sample for Salmonella typhi testing?
Boil and repeat testing after 15 minutes
174
Which type of cell increases in synovial fluid during infection?
Neutrophils
175
What happens to white blood cells in urine that stands too long?
WBCs disintegrate
176
Urine strip shows 1+ leukocytes and negative nitrite. What should be reported?
Report as NORMAL
177
Prism-shaped crystals in urine are typically:
Triple phosphate
178
What test differentiates myeloblasts from monoblasts?
Non-Specific Esterase (NSE)
179
Which hematology parameters are affected by lipemia?
MCH, MCHC, Hemoglobin
180
What is the typical appearance of an atypical lymphocyte?
Low nucleus-to-cytoplasm (N:C) ratio
181
If sickle cells are seen on a smear, what should be done?
Perform hemoglobin electrophoresis
182
Which cell is characteristically seen in chronic lymphocytic leukemia (CLL)?
Smudge cell
183
If a healthy patient has prolonged PTT, what should be done?
Check previous results for comparison
184
Which cell is not typically seen during infection?
Hypersegmented neutrophils
185
What is the formula to compute corrected WBC?
(WBC × 100) / (NRBC + 100)
186
An increase in target cells may indicate:
Liver disease or thalassemia
187
Schistocytes are increased in which condition?
Hemolytic uremic syndrome (HUS)
188
If MCV is normal but RDW is increased (e.g., MCV = 80%, RDW = 20%), the likely diagnosis is:
Early normocytic normochromic anemia
189
Osmotic fragility test shows increased lysis. What condition does this indicate?
Hereditary spherocytosis
190
What is the standard processing time for ESR testing?
2 hours
191
Which WBC shows the most forward scatter in flow cytometry?
Monocyte
192
Which condition causes increased factor VIII?
Fractionated heparin (as part of acute phase response)
193
A clotted specimen primarily affects which parameters?
WBC and platelet count
194
Which inclusion body cannot be stained with Romanowsky stain?
Heinz bodies
195
How is MCV (mean corpuscular volume) calculated?
(Hematocrit × 10) / RBC count
196
Rule of 3: Hemoglobin is approximately one-third of hematocrit. If Hct is 45%, what is the expected hemoglobin?
15 g/dL
197
What should be done if high MCV is suspected due to cold agglutinins?
Pre-warm the sample
198
Platelet count is low due to satellitism. What is the corrective action?
Recollect the sample using sodium citrate
199
What is the platelet count status in disseminated intravascular coagulation (DIC)?
Thrombocytopenia
200
When should calibration and QC be performed on an analyzer?
Daily, after maintenance, or when results deviate from expected values
201
When should a specimen and test result be repeated?
If results are critically abnormal, inconsistent, or affected by known interferences
202
When should machine maintenance be performed?
As per manufacturer guidelines and when errors or issues are observed
203
How is standard deviation (SD) calculated?
SD = (CV × mean) / 100
204
How is coefficient of variation (CV%) calculated?
CV% = (SD / mean) × 100
205
How is creatinine clearance calculated?
[(Urine creatinine × urine volume) / (plasma creatinine × time)] × 1.73 / BSA
206
A standard was diluted twice. What is the impact on the test result?
Falsely high result
207
A downward trend in a QC graph indicates what type of error?
Systematic error
208
A QC value of 125 is observed within acceptable range. What should you do?
Accept the result
209
Decreased sodium and potassium levels suggest which condition?
Addison’s disease
210
Upon detecting increased potassium, what should be done?
Repeat the collection
211
Which of the following test results requires an immediate phone call to the physician?
Potassium 7.6 mmol/L
212
If potassium is increased, what is the first step?
Verify the result
213
What can cause a false positive in freezing point depression osmolality testing?
Lipemia
214
Acetaminophen level is 88 µmol/L. What should be done?
Confirm the timing of the second dose
215
A high osmolal gap is associated with the ingestion of which substance?
Alcohol
216
What is a common disadvantage of Point-of-Care Testing (POCT)?
Expensive
217
Blood glucose is 14 mmol/L. What should be done next?
Verify with patient condition or previous results (confirm)
218
What is the primary purpose of dehydration in tissue processing?
To remove water and allow infiltration with paraffin wax
219
Fungal elements are overstained with silver. What is the corrective action?
Recut and restain the tissue
220
What does Alcian blue at pH 2.5 stain?
Colonic mucin (acid mucopolysaccharides)
221
What causes overstaining with Alcian blue?
Prolonged staining or improper pH
222
What should not be stored on the floor with a hydrant nearby?
Corrosive acids (e.g., glacial acetic acid)
223
What happens when tissue is cut too fast during microtomy?
Sections curl
224
Tissue slide falls off during staining. What is a likely cause?
Alkalinity of the solution
225
What does a dark brown pigment on H&E stain indicate?
Iron, demonstrated with Perl’s Prussian Blue
226
Glycogen artifacts are most likely due to what issue?
Inadequate fixation
227
How can ice crystal artifact be avoided?
Freeze tissue immediately
228
How should silver waste solutions be disposed of?
According to hazardous chemical disposal protocol (e.g., designated chemical waste container)
229
What is the original color of muscle fibers in Masson’s Trichrome before differentiation?
Yellow
230
What is a critical step in specimen preparation for PCR?
Avoiding contamination and using DNAse/RNAse-free reagents
231
What molecule does Southern blot detect?
DNA
232
How long should you wait before opening a centrifuge after a tube breaks?
30 minutes
233
Where should sharps be discarded?
In a rigid, puncture-proof sharps container
234
What is the term for mislabeled blood specimen?
Negligence
235
Giving test results over the phone without proper verification is a:
Breach of confidentiality
236
What factor can negatively affect communication?
Tone or posture
237
What type of fire extinguisher should be used if a centrifuge motor catches fire?
Type C (electrical fires)
238
You are asked to take on a new shift. What is the best response?
Discuss the benefits and assess availability
239
How should a patient’s identity be confirmed?
Ask for full name and date of birth
240
What should be done immediately in the case of an acid spill on the skin?
Flush with copious amounts of water
241
What is a benefit of maintaining an accurate inventory in the lab?
Reduced cost
242
When should a blood collection be refused?
When the patient is aggressive
243
In which case is there a risk of exposure during aerobic sample handling?
During tube-to-tube transfer
244
What should be done if the barcode scanner is not working?
Reboot the scanner
245
What is the basis of equitable healthcare?
Identity (not income or gender) — refers to patient-centered care, possibly social determinants of health
246
What should be done if there is insufficient CSF volume received?
Ask the doctor to prioritize which test to perform
247
If a doctor wants to add a test after the sample has been collected, what should you do first?
Check the LIS for the date and time of collection
248
What is the proper site for a heel puncture in a 3-day-old baby?
Medial or lateral plantar surface of the heel
249
What is the first action if a colleague experiences an electric shock?
Unplug the socket (if safe to do so)
250
What condition is associated with polychromasia on a peripheral smear?
a) Iron deficiency anemia (IDA)
251
Which of the following is not seen in Disseminated Intravascular Coagulation (DIC)?
Thrombocytosis
252
Which of the following is not commonly seen in bacterial infections?
a) Hypersegmentation
## Footnote
Dohle bodies and toxic granules are typical of bacterial infections.
253
A new dialysis clinic opens in the area. Which departments will likely see an increased workload?
c) Hematology and Chemistry
254
Which type of cell increases in synovial fluid during infection?
Neutrophils
255
What crystal type has a prism or coffin-lid shape in urine?
Triple phosphate
256
What is associated with macro-ovalocytes on a histogram?
a) Shift to the right
257
What should be done if plasma is delivered without dry ice?
a) Discard
258
What is the typical appearance of atypical lymphocytes on a smear?
Low nucleus-to-cytoplasm (N:C) ratio
259
What is the formula for corrected WBC count when nucleated RBCs are present?
Corrected WBC = (WBC × 100) / (NRBC + 100)
260
Which white blood cell has the most forward scatter in flow cytometry?
a) Monocyte
261
What should be done when a low platelet count is due to platelet satellitism?
Recollect the sample using a citrate tube.
262
What electrolyte pattern is typically seen in hyperparathyroidism?
Increased calcium, decreased phosphate
263
An increase in Total Iron Binding Capacity (TIBC) is associated with which condition?
Iron deficiency anemia (IDA)
264
What condition shows increased APTT with normal bleeding time?
Hemophilia (e.g., Factor VIII or IX deficiency)
265
What are Heinz bodies composed of?
Denatured hemoglobin
266
What test is used to confirm sickle cell anemia?
Hemoglobin electrophoresis
267
Which material can cause a false-positive oxidase test?
b) Iron (e.g., nichrome wire)
268
What should be done if tubes break in a centrifuge?
Wait 30 minutes before opening the lid.
269
Why is an MLT required to perform blood collection at least once per year?
a) Process improvement
270
What should be done with tissue submitted in formalin for culture?
Reject the specimen.
271
What is the effect of an increased number of leukemic patients in a facility?
Increased workload in the blood bank.
272
Ground glass appearance observed. What should you do?
c) Inform supervisor
273
What method is used to assess urine colony count when colony count is <1×10⁵?
Fluorometry with acridine orange
274
In electrophoresis at pH 7.8, in which direction does DNA migrate?
a) Towards the anode
275
What protein level is typically low in multiple myeloma?
Albumin
276
What is used as phenotype control in antigen testing?
Heterozygous cells
277
Which analyte is time-sensitive for blood collection?
Cortisol
278
Hemoglobin level increases a few days after transfusion. What is the likely reason?
Bone marrow recovery or erythropoiesis post-treatment
## Footnote
full choices needed for precision.
279
What causes a high osmolal gap?
Alcohol
280
What are the growth conditions of Bacteroides species?
Anaerobic
281
Which tissue is used as control for Perl’s Prussian Blue (PPB) stain?
Liver
282
What happens to leukocytes in urine that stands at room temperature?
They lyse
283
What should you do if the patient appears nervous before blood collection?
a) Show professionalism
284
Who in management is responsible for ensuring your safety?
Due diligence
285
How much blood is required to prepare 750 mL of blood agar?
37.5 mL (5%)
286
What is the purpose of resins in culture media?
To absorb antibiotics
287
You received 300 mL of CSF but multiple tests are requested. What should you do?
Call the doctor to ask which test to prioritize
288
What is the result of incubating too short in susceptibility testing?
b) Patient and QC falsely low
289
A pipette dispenses 20 µL but was set to 0.2 mL. What should be done?
Recalibrate
290
What causes fragmentation in frozen tissue sections?
a) Temperature too warm
291
One side is dark during Kohler illumination. What adjustment is needed?
Adjust centering screws
292
What is a disadvantage of point-of-care testing (POCT)?
Expensive
293
What is the effect of storing a cold agglutinin sample in the fridge overnight?
False increase
294
What is the most effective way to detect an organism?
Isolation and identification
295
How do you compute osmolality (calculated)?
(2 × Na⁺) + (glucose / 18) + (BUN / 2.8)
296
What is the minimum radiation dose for irradiated blood products?
a) 25 Gy
297
What is the best purpose for a frozen section?
Enzyme studies
298
Hemoglobin result increases after a few days. What is the likely cause?
a) Dehydration
299
What is the maximum recommended number of blood cultures in 24 hours?
b) 3 (Equal to or less than 3)
300
What is the correct technique for urine inoculation?
Vertical streaking
301
Which organism is commonly associated with burn infections?
Pseudomonas aeruginosa
302
What organism is primarily responsible for bacterial vaginosis?
Gardnerella vaginalis
303
Mislabelled sample is considered what type of violation?
Negligence
304
What is the proper order or concern in PPE (Personal Protective Equipment)?
Donning: Gown → Mask → Goggles → Gloves
## Footnote
Clarify the specific question if it was about donning/doffing or something else.
305
Which antibiotic is used in susceptibility testing of Streptococcus pneumoniae?
Oxacillin (for screening penicillin resistance)
306
What should be done if urine is turbid before performing an osmolality test?
Centrifuge the specimen
307
What is the most common causative organism for subacute bacterial endocarditis?
Viridans group streptococci
308
What causes thick and thin sections during microtomy?
Loose knife
309
What are the control organisms for the DNase test?
Serratia marcescens (positive) and Escherichia coli (negative)
310
What test should be done if spherocytes are seen in a blood smear?
Direct Antiglobulin Test (DAT)
311
How should acids be stored in the lab?
In a vented cabinet (acid storage cabinet, often low gravity)
