ASCP CERTIFICATION EXAM 2025/2026
LABORATORY PROCEDURES WITH VERIFIED
QUESTIONS AND ANSWERS
2026 Exam · 98 Questions · With Rationales
ASCPati.
CERTIFICATION EXAM 2025/2026 LABORATORY PROCEDURES WITH VERIFIED QUESTIONS AND ANSWERS
Question: 1 of 98
A bone marrow aspirate shows marked erythroid hyperplasia with numerous binucleate and multinucleate
erythroid precursors, and Prussian blue staining reveals ring sideroblasts comprising 65% of erythroblasts.
A. Deficiency of pyridoxine-responsive delta-aminolevulinic acid synthase (ALAS2) activity
B. Loss-of-function mutation in the SLC25A38 mitochondrial glycine transporter
C. Somatic SF3B1 spliceosome mutation altering iron-sulfur cluster assembly
D. Autoimmune destruction of erythroblasts mediated by IgG anti-erythroblast antibodies
PREVIOUS CONTINUE
A bone marrow aspirate shows marked erythroid hyperplasia with numerous binucleate
and multinucleate erythroid precursors, and Prussian blue staining reveals ring
sideroblasts comprising 65% of erythroblasts. Which underlying defect best explains
these findings?
A. Deficiency of pyridoxine-responsive delta-aminolevulinic acid synthase (ALAS2) activity
B. Loss-of-function mutation in the SLC25A38 mitochondrial glycine transporter
(Correct) C. Somatic SF3B1 spliceosome mutation altering iron-sulfur cluster assembly
D. Autoimmune destruction of erythroblasts mediated by IgG anti-erythroblast antibodies
Correct Answer: C
Ring sideroblasts exceeding 15% with dysplastic, binucleate erythroid precursors and no anemia reversal after
pyridoxine strongly suggest MDS with SF3B1 mutation (MDS-RS), which impairs mitochondrial iron-sulfur
cluster biogenesis. ALAS2 defects cause X-linked sideroblastic anemia (typically pyridoxine-responsive, without
multilineage dysplasia), SLC25A38 mutations cause congenital sideroblastic anemia in children, and immune
erythroblastopenia lacks ring sideroblasts.
Page 1 | ASCP CERTIFICATION EXAM 2025/2026 LABORATORY PROCEDURES WITH VERIFIED QUESTIONS AND ANSWERS 2026
, ASCP CERTIFICATION EXAM 2025/2026
LABORATORY PROCEDURES WITH VERIFIED
QUESTIONS AND ANSWERS
2026 Exam · 98 Questions · With Rationales
ASCPati.
CERTIFICATION EXAM 2025/2026 LABORATORY PROCEDURES WITH VERIFIED QUESTIONS AND ANSWERS
Question: 2 of 98
A plasma sample for routine coagulation testing is inadvertently collected from a line infusing unfractionated
heparin. Which pattern of laboratory results would most specifically indicate heparin contamination rather than
A. Prolonged PT and aPTT that both correct with normal plasma mixing study
B. Prolonged aPTT with normal PT and normal thrombin time
C. Prolonged aPTT, prolonged thrombin time, and correction of aPTT by heparinase or protamine
D. Prolonged PT and aPTT with decreased fibrinogen and elevated D-dimer
PREVIOUS CONTINUE
A plasma sample for routine coagulation testing is inadvertently collected from a line
infusing unfractionated heparin. Which pattern of laboratory results would most
specifically indicate heparin contamination rather than a true coagulopathy?
A. Prolonged PT and aPTT that both correct with normal plasma mixing study
B. Prolonged aPTT with normal PT and normal thrombin time
(Correct) C. Prolonged aPTT, prolonged thrombin time, and correction of aPTT by heparinase or
protamine
D. Prolonged PT and aPTT with decreased fibrinogen and elevated D-dimer
Correct Answer: C
Heparin potentiates antithrombin, inhibiting thrombin and factor Xa, so it prolongs the aPTT, thrombin time, and
often the PT; the thrombin time is exquisitely sensitive to heparin. Correction of the aPTT by heparinase (or
protamine) confirms heparin effect. A true factor deficiency corrects with normal plasma (A), factor XII
deficiency prolongs aPTT only (B), and DIC produces hypofibrinogenemia with elevated D-dimer (D).
Page 2 | ASCP CERTIFICATION EXAM 2025/2026 LABORATORY PROCEDURES WITH VERIFIED QUESTIONS AND ANSWERS 2026
, ASCP CERTIFICATION EXAM 2025/2026
LABORATORY PROCEDURES WITH VERIFIED
QUESTIONS AND ANSWERS
2026 Exam · 98 Questions · With Rationales
ASCPati.
CERTIFICATION EXAM 2025/2026 LABORATORY PROCEDURES WITH VERIFIED QUESTIONS AND ANSWERS
Question: 3 of 98
A serum protein electrophoresis pattern shows a broad gamma-region band with a monoclonal spike, and
immunofixation reveals IgG kappa. Serum free light chain (sFLC) assay shows an abnormal kappa/lambda
A. Bone marrow plasmacytosis of 35% with lytic bone lesions
B. Congo red-positive tissue deposits with apple-green birefringence and elevated NT-proBNP
C. Hypercalcemia, renal insufficiency, anemia, and lytic lesions (CRAB criteria)
D. Serum M-protein > 3 g/dL with > 10% clonal plasma cells
PREVIOUS CONTINUE
A serum protein electrophoresis pattern shows a broad gamma-region band with a
monoclonal spike, and immunofixation reveals IgG kappa. Serum free light chain (sFLC)
assay shows an abnormal kappa/lambda ratio of 42 (normal 0.26-1.65). Which additional
finding is most consistent with AL amyloidosis rather than multiple myeloma?
A. Bone marrow plasmacytosis of 35% with lytic bone lesions
(Correct) B. Congo red-positive tissue deposits with apple-green birefringence and elevated
NT-proBNP
C. Hypercalcemia, renal insufficiency, anemia, and lytic lesions (CRAB criteria)
D. Serum M-protein > 3 g/dL with > 10% clonal plasma cells
Correct Answer: B
AL amyloidosis is defined by Congo red-positive amyloid deposits with apple-green birefringence under
polarized light; cardiac involvement (elevated NT-proBNP) is common. Multiple myeloma (A, C, D) requires
CRAB features or specific clonal burden thresholds, but amyloidosis can occur with low tumor burden. The
abnormal sFLC ratio supports a clonal plasma cell disorder but does not distinguish the two entities.
Page 3 | ASCP CERTIFICATION EXAM 2025/2026 LABORATORY PROCEDURES WITH VERIFIED QUESTIONS AND ANSWERS 2026
, ASCP CERTIFICATION EXAM 2025/2026
LABORATORY PROCEDURES WITH VERIFIED
QUESTIONS AND ANSWERS
2026 Exam · 98 Questions · With Rationales
ASCPati.
CERTIFICATION EXAM 2025/2026 LABORATORY PROCEDURES WITH VERIFIED QUESTIONS AND ANSWERS
Question: 4 of 98
A patient's serum creatinine is 2.8 mg/dL (stable), and a 24-hour urine collection yields 1.2 g protein. The
calculated protein/creatinine ratio on a random urine sample is 3.5 mg/mg. Which statement best interprets
A. The random protein/creatinine ratio is invalid because it must be calculated from a 24-hour collection.
B. The protein/creatinine ratio of 3.5 mg/mg corresponds to approximately 3.5 g protein per day, consistent with
C. The discrepancy between the 24-hour protein (1.2 g) and the ratio (3.5 mg/mg) indicates a collection error.
D. The ratio is unreliable because creatinine excretion varies with muscle mass and diet.
PREVIOUS CONTINUE
A patient's serum creatinine is 2.8 mg/dL (stable), and a 24-hour urine collection yields 1.2
g protein. The calculated protein/creatinine ratio on a random urine sample is 3.5 mg/mg.
Which statement best interprets these results?
A. The random protein/creatinine ratio is invalid because it must be calculated from a 24-hour
collection.
(Correct) B. The protein/creatinine ratio of 3.5 mg/mg corresponds to approximately 3.5 g protein per
day, consistent with nephrotic-range proteinuria.
C. The discrepancy between the 24-hour protein (1.2 g) and the ratio (3.5 mg/mg) indicates a
collection error.
D. The ratio is unreliable because creatinine excretion varies with muscle mass and diet.
Correct Answer: B
The urine protein/creatinine ratio (mg/mg) approximates 24-hour protein excretion in grams per day when
creatinine excretion is near 1 g/day, so 3.5 mg/mg 3.5 g/day, which is nephrotic range. The 24-hour value of 1.2
g may reflect incomplete collection or day-to-day variability. The ratio is valid on a random sample (A), and
while creatinine excretion varies (D), the ratio remains a useful estimate; the discrepancy does not
automatically indicate error (C).
Page 4 | ASCP CERTIFICATION EXAM 2025/2026 LABORATORY PROCEDURES WITH VERIFIED QUESTIONS AND ANSWERS 2026
LABORATORY PROCEDURES WITH VERIFIED
QUESTIONS AND ANSWERS
2026 Exam · 98 Questions · With Rationales
ASCPati.
CERTIFICATION EXAM 2025/2026 LABORATORY PROCEDURES WITH VERIFIED QUESTIONS AND ANSWERS
Question: 1 of 98
A bone marrow aspirate shows marked erythroid hyperplasia with numerous binucleate and multinucleate
erythroid precursors, and Prussian blue staining reveals ring sideroblasts comprising 65% of erythroblasts.
A. Deficiency of pyridoxine-responsive delta-aminolevulinic acid synthase (ALAS2) activity
B. Loss-of-function mutation in the SLC25A38 mitochondrial glycine transporter
C. Somatic SF3B1 spliceosome mutation altering iron-sulfur cluster assembly
D. Autoimmune destruction of erythroblasts mediated by IgG anti-erythroblast antibodies
PREVIOUS CONTINUE
A bone marrow aspirate shows marked erythroid hyperplasia with numerous binucleate
and multinucleate erythroid precursors, and Prussian blue staining reveals ring
sideroblasts comprising 65% of erythroblasts. Which underlying defect best explains
these findings?
A. Deficiency of pyridoxine-responsive delta-aminolevulinic acid synthase (ALAS2) activity
B. Loss-of-function mutation in the SLC25A38 mitochondrial glycine transporter
(Correct) C. Somatic SF3B1 spliceosome mutation altering iron-sulfur cluster assembly
D. Autoimmune destruction of erythroblasts mediated by IgG anti-erythroblast antibodies
Correct Answer: C
Ring sideroblasts exceeding 15% with dysplastic, binucleate erythroid precursors and no anemia reversal after
pyridoxine strongly suggest MDS with SF3B1 mutation (MDS-RS), which impairs mitochondrial iron-sulfur
cluster biogenesis. ALAS2 defects cause X-linked sideroblastic anemia (typically pyridoxine-responsive, without
multilineage dysplasia), SLC25A38 mutations cause congenital sideroblastic anemia in children, and immune
erythroblastopenia lacks ring sideroblasts.
Page 1 | ASCP CERTIFICATION EXAM 2025/2026 LABORATORY PROCEDURES WITH VERIFIED QUESTIONS AND ANSWERS 2026
, ASCP CERTIFICATION EXAM 2025/2026
LABORATORY PROCEDURES WITH VERIFIED
QUESTIONS AND ANSWERS
2026 Exam · 98 Questions · With Rationales
ASCPati.
CERTIFICATION EXAM 2025/2026 LABORATORY PROCEDURES WITH VERIFIED QUESTIONS AND ANSWERS
Question: 2 of 98
A plasma sample for routine coagulation testing is inadvertently collected from a line infusing unfractionated
heparin. Which pattern of laboratory results would most specifically indicate heparin contamination rather than
A. Prolonged PT and aPTT that both correct with normal plasma mixing study
B. Prolonged aPTT with normal PT and normal thrombin time
C. Prolonged aPTT, prolonged thrombin time, and correction of aPTT by heparinase or protamine
D. Prolonged PT and aPTT with decreased fibrinogen and elevated D-dimer
PREVIOUS CONTINUE
A plasma sample for routine coagulation testing is inadvertently collected from a line
infusing unfractionated heparin. Which pattern of laboratory results would most
specifically indicate heparin contamination rather than a true coagulopathy?
A. Prolonged PT and aPTT that both correct with normal plasma mixing study
B. Prolonged aPTT with normal PT and normal thrombin time
(Correct) C. Prolonged aPTT, prolonged thrombin time, and correction of aPTT by heparinase or
protamine
D. Prolonged PT and aPTT with decreased fibrinogen and elevated D-dimer
Correct Answer: C
Heparin potentiates antithrombin, inhibiting thrombin and factor Xa, so it prolongs the aPTT, thrombin time, and
often the PT; the thrombin time is exquisitely sensitive to heparin. Correction of the aPTT by heparinase (or
protamine) confirms heparin effect. A true factor deficiency corrects with normal plasma (A), factor XII
deficiency prolongs aPTT only (B), and DIC produces hypofibrinogenemia with elevated D-dimer (D).
Page 2 | ASCP CERTIFICATION EXAM 2025/2026 LABORATORY PROCEDURES WITH VERIFIED QUESTIONS AND ANSWERS 2026
, ASCP CERTIFICATION EXAM 2025/2026
LABORATORY PROCEDURES WITH VERIFIED
QUESTIONS AND ANSWERS
2026 Exam · 98 Questions · With Rationales
ASCPati.
CERTIFICATION EXAM 2025/2026 LABORATORY PROCEDURES WITH VERIFIED QUESTIONS AND ANSWERS
Question: 3 of 98
A serum protein electrophoresis pattern shows a broad gamma-region band with a monoclonal spike, and
immunofixation reveals IgG kappa. Serum free light chain (sFLC) assay shows an abnormal kappa/lambda
A. Bone marrow plasmacytosis of 35% with lytic bone lesions
B. Congo red-positive tissue deposits with apple-green birefringence and elevated NT-proBNP
C. Hypercalcemia, renal insufficiency, anemia, and lytic lesions (CRAB criteria)
D. Serum M-protein > 3 g/dL with > 10% clonal plasma cells
PREVIOUS CONTINUE
A serum protein electrophoresis pattern shows a broad gamma-region band with a
monoclonal spike, and immunofixation reveals IgG kappa. Serum free light chain (sFLC)
assay shows an abnormal kappa/lambda ratio of 42 (normal 0.26-1.65). Which additional
finding is most consistent with AL amyloidosis rather than multiple myeloma?
A. Bone marrow plasmacytosis of 35% with lytic bone lesions
(Correct) B. Congo red-positive tissue deposits with apple-green birefringence and elevated
NT-proBNP
C. Hypercalcemia, renal insufficiency, anemia, and lytic lesions (CRAB criteria)
D. Serum M-protein > 3 g/dL with > 10% clonal plasma cells
Correct Answer: B
AL amyloidosis is defined by Congo red-positive amyloid deposits with apple-green birefringence under
polarized light; cardiac involvement (elevated NT-proBNP) is common. Multiple myeloma (A, C, D) requires
CRAB features or specific clonal burden thresholds, but amyloidosis can occur with low tumor burden. The
abnormal sFLC ratio supports a clonal plasma cell disorder but does not distinguish the two entities.
Page 3 | ASCP CERTIFICATION EXAM 2025/2026 LABORATORY PROCEDURES WITH VERIFIED QUESTIONS AND ANSWERS 2026
, ASCP CERTIFICATION EXAM 2025/2026
LABORATORY PROCEDURES WITH VERIFIED
QUESTIONS AND ANSWERS
2026 Exam · 98 Questions · With Rationales
ASCPati.
CERTIFICATION EXAM 2025/2026 LABORATORY PROCEDURES WITH VERIFIED QUESTIONS AND ANSWERS
Question: 4 of 98
A patient's serum creatinine is 2.8 mg/dL (stable), and a 24-hour urine collection yields 1.2 g protein. The
calculated protein/creatinine ratio on a random urine sample is 3.5 mg/mg. Which statement best interprets
A. The random protein/creatinine ratio is invalid because it must be calculated from a 24-hour collection.
B. The protein/creatinine ratio of 3.5 mg/mg corresponds to approximately 3.5 g protein per day, consistent with
C. The discrepancy between the 24-hour protein (1.2 g) and the ratio (3.5 mg/mg) indicates a collection error.
D. The ratio is unreliable because creatinine excretion varies with muscle mass and diet.
PREVIOUS CONTINUE
A patient's serum creatinine is 2.8 mg/dL (stable), and a 24-hour urine collection yields 1.2
g protein. The calculated protein/creatinine ratio on a random urine sample is 3.5 mg/mg.
Which statement best interprets these results?
A. The random protein/creatinine ratio is invalid because it must be calculated from a 24-hour
collection.
(Correct) B. The protein/creatinine ratio of 3.5 mg/mg corresponds to approximately 3.5 g protein per
day, consistent with nephrotic-range proteinuria.
C. The discrepancy between the 24-hour protein (1.2 g) and the ratio (3.5 mg/mg) indicates a
collection error.
D. The ratio is unreliable because creatinine excretion varies with muscle mass and diet.
Correct Answer: B
The urine protein/creatinine ratio (mg/mg) approximates 24-hour protein excretion in grams per day when
creatinine excretion is near 1 g/day, so 3.5 mg/mg 3.5 g/day, which is nephrotic range. The 24-hour value of 1.2
g may reflect incomplete collection or day-to-day variability. The ratio is valid on a random sample (A), and
while creatinine excretion varies (D), the ratio remains a useful estimate; the discrepancy does not
automatically indicate error (C).
Page 4 | ASCP CERTIFICATION EXAM 2025/2026 LABORATORY PROCEDURES WITH VERIFIED QUESTIONS AND ANSWERS 2026
