AMT MLT Practice Exam Questions and Answers

Start your preparation with this complete AMT MLT Practice Test pack designed to help you pass the MLT AMT certification exam with confidence on your first attempt. This comprehensive exam prep resource includes 870 high-quality multiple-choice questions with fully detailed explanations, carefully written to reflect real exam difficulty and current 2026 testing standards.

Whether you are a first-time student, recent graduate, or working laboratory professional preparing for certification, this study guide provides the structure and clarity needed for serious preparation. Each question focuses on practical laboratory knowledge, clinical reasoning, and exam-style scenarios to help you think like a certified Medical Laboratory Technician.

This downloadable study resource is ideal for focused revision and structured practice. You can study anytime using the printable PDF format, making it easy to review key concepts, test your knowledge, and build exam confidence before test day. If you want a reliable and effective MLT AMT preparation tool without wasting time on outdated materials, this practice exam pack is built for you.

Who Should Use This Practice Exam?

This AMT MLT Practice Test is designed for serious candidates who want structured and realistic exam preparation. It is ideal for:

• Students preparing for the AMT Medical Laboratory Technician certification
• First-time exam takers who want real exam-style practice
• MLT graduates reviewing core laboratory concepts
• Working lab professionals seeking certification or recertification
• Retakers who want stronger preparation for their next attempt
• Anyone who prefers printable, downloadable PDF study material
• Candidates who want a complete 870-question practice resource

If you are looking for a focused and reliable MLT AMT exam preparation solution, this practice question bank provides the depth and clarity needed for success.

What You Will Learn from This AMT MLT Practice Test

This comprehensive study resource helps you master the key areas tested on the certification exam while strengthening your understanding of real laboratory procedures and clinical decision-making.

With this practice exam, you will:

• Practice with realistic multiple-choice questions similar to the actual exam
• Understand correct answers through detailed, easy-to-follow explanations
• Strengthen knowledge across all major MLT subject areas
• Identify weak topics and focus your revision effectively
• Improve test-taking speed and accuracy
• Build confidence for exam day
• Review essential laboratory principles used in real clinical settings

The questions are designed to reinforce both foundational knowledge and advanced problem-solving skills. Each explanation goes beyond simple answers, helping you understand the reasoning behind correct responses so you can apply concepts confidently during the exam.

Complete Coverage of All Major MLT Topics

This AMT MLT Practice Test includes 870 questions that cover the full range of topics typically tested on the certification exam. The content is structured to provide balanced preparation across all major laboratory disciplines.

Core subjects covered include:

• Hematology and coagulation
• Clinical chemistry
• Microbiology and parasitology
• Immunology and serology
• Blood banking and transfusion medicine
• Urinalysis and body fluids
• Laboratory safety and quality control
• Instrumentation and laboratory procedures

Each section is designed to mirror real exam expectations and ensure you gain a complete understanding of essential laboratory concepts. The goal is not just memorization but true comprehension that supports both exam success and real-world laboratory performance.

What’s Included in this Practice Exam Questions?

Your downloadable exam prep package includes everything needed for structured and effective preparation:

✔ 870 updated practice questions
✔ Multiple-choice format (real exam style)
✔ Fully detailed answer explanations
✔ Coverage of all major MLT exam topics
✔ Printable and mobile-friendly PDF format
✔ Organized for easy study and review
✔ Instant download access after purchase

This complete practice set allows you to study at your own pace, review difficult topics, and return to questions as needed. The printable format also makes it convenient for offline study sessions.

Realistic Exam-Style Practice for Better Results

Many candidates struggle with certification exams not because they lack knowledge, but because they lack realistic practice. This question bank is designed to simulate actual exam conditions and help you prepare effectively.

You will encounter:

• Scenario-based clinical questions
• Calculation and interpretation problems
• Quality control and lab math concepts
• Blood bank compatibility and antibody cases
• Microbiology identification scenarios
• Chemistry and hematology analysis questions

This structured approach ensures you become familiar with how questions are presented and how to analyze them quickly and accurately during the exam.

Why Choose This Over Free Practice Tests?

Free practice tests online can be helpful, but they are often incomplete, outdated, or poorly structured. Many lack detailed explanations and do not reflect real exam difficulty.

This MLT AMT exam prep resource is created for serious candidates who want reliable and efficient preparation.

Students choose this resource because it is:

• Comprehensive and structured
• Written in clear, easy-to-understand language
• Based on current exam topics and standards
• Designed to match real exam difficulty
• Focused on helping you pass faster
• Organized for efficient study sessions
• Available instantly with no waiting

Instead of searching multiple websites for scattered practice questions, you get a complete and organized preparation system in one place.

Study Smarter and Build Real Exam Confidence

Preparing for certification requires more than reading textbooks. Success comes from practicing with realistic questions and understanding how to apply knowledge in exam scenarios.

This AMT MLT Practice Test helps you:

• Strengthen critical thinking skills
• Improve accuracy and speed
• Recognize common exam patterns
• Build confidence through repetition
• Reduce exam anxiety through preparation

By working through 870 carefully developed questions and explanations, you gain the practice and confidence needed to approach exam day fully prepared.

Instant Access and Flexible Study

After download, you can begin studying immediately. The format allows you to:

• Study on mobile, tablet, or computer
• Print for offline review
• Use for daily revision sessions
• Practice in timed exam conditions
• Review explanations anytime

This flexibility makes it easy to fit exam preparation into your schedule, whether you are studying full-time or balancing work and coursework.

Prepare with Confidence

If you are preparing for certification and want a reliable, structured, and comprehensive study resource, this MLT AMT practice exam pack provides the depth and realism needed to succeed.

With 870 exam-style questions, detailed explanations, and complete topic coverage, you can strengthen your knowledge, improve test performance, and move closer to passing the exam with confidence.

Download your complete AMT MLT Practice Test today and start preparing smarter for exam success.

Sample Questions and Answers

Question 1

Which anticoagulant tube is primarily used for hematology testing such as CBC?

A. Sodium citrate
B. Heparin
C. EDTA
D. Fluoride oxalate

Correct Answer: C. EDTA

Detailed Explanation:
EDTA (ethylenediaminetetraacetic acid) is the preferred anticoagulant for hematology testing because it preserves cellular morphology and prevents clotting by binding calcium. This ensures accurate counting and evaluation of red blood cells, white blood cells, and platelets. Sodium citrate is mainly used for coagulation testing, heparin for chemistry testing, and fluoride oxalate for glucose analysis. EDTA maintains cell integrity longer than other anticoagulants, which is essential for automated and manual blood cell analysis. Using an incorrect tube can lead to inaccurate results, including cell distortion or clot formation that invalidates the sample.

Question 2

Which white blood cell type is most commonly elevated during bacterial infections?

A. Lymphocytes
B. Monocytes
C. Neutrophils
D. Eosinophils

Correct Answer: C. Neutrophils

Detailed Explanation:
Neutrophils are the body’s first line of defense against bacterial infections and are typically elevated in acute bacterial conditions. A high neutrophil count, known as neutrophilia, often indicates an active infection or inflammation. These cells function by engulfing and destroying bacteria through phagocytosis. Lymphocytes are more associated with viral infections, eosinophils increase in allergic reactions and parasitic infections, and monocytes rise during chronic infections and inflammatory disorders. Recognizing neutrophilia helps laboratory professionals correlate results with clinical conditions and assists physicians in diagnosing bacterial infections promptly.

Question 3

Which test is most commonly used to evaluate kidney function?

A. ALT
B. Creatinine
C. Bilirubin
D. Amylase

Correct Answer: B. Creatinine

Detailed Explanation:
Serum creatinine is a key indicator of kidney function because it reflects the glomerular filtration rate (GFR). Creatinine is a waste product produced by muscle metabolism and is normally filtered out by the kidneys. Elevated creatinine levels suggest impaired kidney function or decreased filtration ability. While BUN is also used to evaluate kidney function, creatinine provides a more specific assessment. ALT measures liver function, bilirubin evaluates liver and bile duct health, and amylase is related to pancreatic function. Monitoring creatinine levels helps clinicians detect kidney disease early and manage treatment effectively.

Question 4

What is the primary purpose of quality control in the clinical laboratory?

A. Increase workload
B. Reduce staff
C. Ensure accuracy and reliability of test results
D. Speed up reporting time

Correct Answer: C. Ensure accuracy and reliability of test results

Detailed Explanation:
Quality control (QC) ensures that laboratory results are accurate, reliable, and consistent. It involves running control samples, calibrating instruments, and monitoring procedures to detect errors before patient results are reported. Effective QC helps prevent diagnostic mistakes, protects patient safety, and ensures compliance with regulatory standards. Without QC, inaccurate results could lead to incorrect treatment decisions. While efficient reporting and workflow are important, the primary goal of QC is maintaining high testing standards and ensuring laboratory data can be trusted by healthcare providers.

Question 5

Which blood component carries oxygen throughout the body?

A. Platelets
B. Plasma
C. Red blood cells
D. White blood cells

Correct Answer: C. Red blood cells

Detailed Explanation:
Red blood cells (RBCs) transport oxygen from the lungs to tissues through hemoglobin, a protein that binds oxygen molecules. They also carry carbon dioxide back to the lungs for removal. Platelets are responsible for clotting, plasma carries nutrients and proteins, and white blood cells fight infection. RBCs are uniquely designed with a biconcave shape that increases surface area for gas exchange and flexibility to pass through small capillaries. A decrease in RBC count or hemoglobin levels can lead to anemia, causing fatigue and reduced oxygen delivery to tissues.

Question 6

Which microorganism is most commonly associated with urinary tract infections (UTIs)?

A. Staphylococcus aureus
B. Escherichia coli
C. Streptococcus pyogenes
D. Mycobacterium tuberculosis

Correct Answer: B. Escherichia coli

Detailed Explanation:
Escherichia coli (E. coli) is the most common cause of urinary tract infections, accounting for the majority of community-acquired cases. This bacterium normally resides in the intestinal tract but can enter the urinary system and multiply, causing infection. Laboratory identification typically involves urine culture and sensitivity testing to guide antibiotic therapy. Staphylococcus aureus can cause UTIs but is less common, while Streptococcus pyogenes is more associated with throat infections and Mycobacterium tuberculosis causes tuberculosis. Accurate identification of E. coli is essential for proper treatment and prevention of complications.

Question 7

What does a high erythrocyte sedimentation rate (ESR) typically indicate?

A. Dehydration
B. Inflammation
C. Hypoglycemia
D. Low platelet count

Correct Answer: B. Inflammation

Detailed Explanation:
An elevated erythrocyte sedimentation rate (ESR) is a nonspecific marker of inflammation. It measures how quickly red blood cells settle at the bottom of a test tube over a set period. Faster settling occurs when inflammatory proteins are present in the blood. High ESR values can indicate infections, autoimmune disorders, or chronic inflammatory diseases such as rheumatoid arthritis. Although ESR does not identify a specific condition, it is useful for monitoring disease progression and response to treatment. Other options like dehydration or hypoglycemia do not directly affect ESR in the same way.

Question 8

Which laboratory department performs prothrombin time (PT) testing?

A. Hematology
B. Microbiology
C. Coagulation
D. Immunology

Correct Answer: C. Coagulation

Detailed Explanation:
Prothrombin time (PT) testing is performed in the coagulation section of the laboratory. It measures how long it takes blood to clot and evaluates the extrinsic and common clotting pathways. PT is commonly used to monitor patients on anticoagulant therapy such as warfarin and to assess liver function or bleeding disorders. Although coagulation is sometimes grouped under hematology, it is typically treated as a specialized section due to its focus on clotting factors and hemostasis. Accurate PT results are critical for managing patient treatment and preventing excessive bleeding or clotting.

Question 9

Which specimen is most appropriate for blood glucose testing?

A. Serum
B. Plasma with fluoride
C. Whole blood without anticoagulant
D. Urine

Correct Answer: B. Plasma with fluoride

Detailed Explanation:
Plasma collected in a fluoride tube is ideal for glucose testing because fluoride inhibits glycolysis, preventing cells from consuming glucose after collection. This preserves accurate glucose levels until analysis. Serum can also be used but may show decreased glucose if processing is delayed. Whole blood without anticoagulant can clot and alter results, while urine glucose testing is less accurate for diagnosing current blood glucose levels. Using fluoride plasma ensures reliable measurement, which is essential for diagnosing diabetes and monitoring glycemic control.

Question 10

Which cell type is responsible for antibody production?

A. T lymphocytes
B. B lymphocytes
C. Neutrophils
D. Basophils

Correct Answer: B. B lymphocytes

Detailed Explanation:
B lymphocytes are responsible for producing antibodies as part of the adaptive immune response. When exposed to an antigen, B cells differentiate into plasma cells that secrete specific antibodies targeting that antigen. These antibodies help neutralize pathogens and mark them for destruction. T lymphocytes play roles in cell-mediated immunity, neutrophils perform phagocytosis, and basophils release histamine during allergic responses. Understanding B cell function is essential in immunology and helps explain vaccine responses, autoimmune diseases, and immune deficiencies.

Question 11

Which test is used to monitor long-term glucose control in diabetic patients?

A. Fasting glucose
B. HbA1c
C. Random glucose
D. Glucose tolerance test

Correct Answer: B. HbA1c

Detailed Explanation:
Hemoglobin A1c (HbA1c) reflects average blood glucose levels over the previous two to three months by measuring glucose attached to hemoglobin in red blood cells. It provides a long-term assessment of diabetes control and helps clinicians adjust treatment plans. Fasting glucose and random glucose tests show only current levels, while the glucose tolerance test evaluates how the body handles sugar over a short period. HbA1c is widely used because it offers a stable and reliable indicator of glycemic control and risk of complications.

Question 12

Which safety practice is most important when handling all patient specimens?

A. Wearing jewelry
B. Universal precautions
C. Working without gloves
D. Ignoring labels

Correct Answer: B. Universal precautions

Detailed Explanation:
Universal precautions require treating all patient specimens as potentially infectious and using appropriate personal protective equipment (PPE) such as gloves, lab coats, and eye protection. This approach prevents exposure to bloodborne pathogens like hepatitis B, hepatitis C, and HIV. Proper labeling, hand hygiene, and safe disposal of sharps are also essential components. Ignoring safety protocols increases the risk of laboratory-acquired infections. Universal precautions are a standard requirement in all clinical laboratories and protect both staff and patients.

Question 13

Which instrument is commonly used to measure hemoglobin levels?

A. Spectrophotometer
B. Centrifuge
C. Microscope
D. Incubator

Correct Answer: A. Spectrophotometer

Detailed Explanation:
A spectrophotometer measures hemoglobin by detecting light absorbance at specific wavelengths after a chemical reaction forms a colored compound. The absorbance is proportional to hemoglobin concentration. This method is widely used in automated hematology analyzers and manual testing. Centrifuges separate blood components, microscopes are used for cell examination, and incubators support microbial growth. Accurate hemoglobin measurement is essential for diagnosing anemia, monitoring blood loss, and assessing overall oxygen-carrying capacity.

Question 14

Which electrolyte is most important for cardiac function?

A. Sodium
B. Potassium
C. Chloride
D. Magnesium

Correct Answer: B. Potassium

Detailed Explanation:
Potassium plays a critical role in cardiac muscle contraction and electrical conduction. Abnormal potassium levels can lead to arrhythmias, which may be life-threatening. Hyperkalemia can cause dangerous heart rhythm disturbances, while hypokalemia can lead to muscle weakness and irregular heartbeat. Although sodium and magnesium also influence cardiac function, potassium has the most direct effect on cardiac electrical activity. Monitoring potassium levels is essential in patients with kidney disease, those taking certain medications, or individuals with heart conditions.

Question 15

Which organism is identified using acid-fast staining?

A. Staphylococcus
B. Mycobacterium
C. Streptococcus
D. Candida

Correct Answer: B. Mycobacterium

Detailed Explanation:
Acid-fast staining is used to identify Mycobacterium species, including Mycobacterium tuberculosis. These bacteria have a waxy cell wall containing mycolic acid that retains stain even after acid-alcohol decolorization. This property distinguishes them from other bacteria. Early detection of acid-fast bacilli is critical for diagnosing tuberculosis and initiating treatment. Staphylococcus and Streptococcus are identified using Gram staining, while Candida is a fungal organism detected through other methods. Proper staining technique ensures accurate identification and infection control.

Question 16

Which blood type is considered the universal donor for red cells?

A. A positive
B. B negative
C. AB positive
D. O negative

Correct Answer: D. O negative

Detailed Explanation:
O negative blood is considered the universal donor for red blood cell transfusions because it lacks A, B, and Rh antigens. This reduces the risk of transfusion reactions when given to patients of different blood types. It is especially important in emergency situations when there is no time for blood typing. However, compatibility testing is still preferred whenever possible. AB positive is the universal recipient for red cells. Understanding blood group compatibility is essential to prevent hemolytic transfusion reactions and ensure patient safety.

Question 17

Which test evaluates liver function?

A. Troponin
B. ALT
C. CK-MB
D. Creatinine

Correct Answer: B. ALT

Detailed Explanation:
Alanine aminotransferase (ALT) is a liver enzyme released into the bloodstream when liver cells are damaged. Elevated ALT levels indicate liver injury from conditions such as hepatitis, fatty liver disease, or medication toxicity. Troponin and CK-MB assess cardiac injury, while creatinine evaluates kidney function. ALT is often measured alongside AST and other liver enzymes to provide a comprehensive picture of liver health. Monitoring ALT helps detect liver disease early and guides treatment decisions.

Question 18

What is the main purpose of centrifugation in the laboratory?

A. Heat samples
B. Separate components by density
C. Sterilize equipment
D. Measure pH

Correct Answer: B. Separate components by density

Detailed Explanation:
Centrifugation separates blood components based on density by spinning samples at high speed. This process allows plasma or serum to be separated from cells for testing. It is essential for chemistry, hematology, and coagulation testing. Proper centrifugation ensures accurate results by preventing contamination between components. Heating samples, sterilizing equipment, and measuring pH are unrelated functions. Correct centrifuge settings and balancing are important to avoid sample damage or equipment malfunction.

Question 19

Which vitamin deficiency leads to megaloblastic anemia?

A. Vitamin C
B. Vitamin D
C. Vitamin B12
D. Vitamin K

Correct Answer: C. Vitamin B12

Detailed Explanation:
Vitamin B12 deficiency leads to megaloblastic anemia characterized by large, immature red blood cells due to impaired DNA synthesis. Patients may also experience neurological symptoms such as numbness and memory issues. Laboratory findings include increased mean corpuscular volume (MCV) and hypersegmented neutrophils. Vitamin B12 is essential for red blood cell production and nerve function. Vitamin C deficiency causes scurvy, vitamin D affects bone health, and vitamin K is involved in clotting. Identifying B12 deficiency allows timely treatment and prevents complications.

Question 20

Which parameter is measured in a complete blood count (CBC)?

A. Cholesterol
B. Hemoglobin
C. Glucose
D. Calcium

Correct Answer: B. Hemoglobin

Detailed Explanation:
A complete blood count (CBC) measures several blood parameters including hemoglobin, hematocrit, red blood cell count, white blood cell count, and platelet count. Hemoglobin measurement is essential for evaluating oxygen-carrying capacity and diagnosing anemia or polycythemia. Cholesterol, glucose, and calcium are measured in chemistry panels rather than CBC. The CBC is one of the most commonly ordered laboratory tests and provides valuable information about overall health, infection, and hematologic disorders. Accurate CBC results guide diagnosis and treatment decisions.

Question 21

A 68-year-old patient presents with fatigue and pallor. CBC results show: Hb 8.2 g/dL, MCV 72 fL, ferritin low, TIBC high. Which condition is most likely?

A. Vitamin B12 deficiency
B. Iron deficiency anemia
C. Aplastic anemia
D. Hemolytic anemia

Correct Answer: B. Iron deficiency anemia

Detailed Explanation:
The patient shows classic findings of iron deficiency anemia: low hemoglobin, low MCV (microcytic), low ferritin (decreased iron stores), and elevated total iron-binding capacity (TIBC), which reflects increased transferrin availability to capture iron. Vitamin B12 deficiency would show macrocytosis (high MCV). Aplastic anemia usually presents with pancytopenia, and hemolytic anemia shows elevated bilirubin and reticulocytes. Iron deficiency is the most consistent diagnosis based on laboratory findings and clinical presentation.

Question 22

A patient’s CBC shows WBC 18,000/µL with 85% neutrophils and band forms present. What does this indicate?

A. Viral infection
B. Acute bacterial infection
C. Allergic reaction
D. Chronic anemia

Correct Answer: B. Acute bacterial infection

Detailed Explanation:
An elevated white blood cell count with neutrophilia and bandemia (increased immature neutrophils) indicates an acute bacterial infection. The bone marrow releases immature neutrophils during severe infection to fight pathogens. This “left shift” is a classic sign of bacterial inflammation. Viral infections usually show lymphocytosis rather than neutrophilia. Recognizing this pattern helps clinicians initiate appropriate antibiotic therapy quickly and monitor infection severity.

Question 23

A patient develops fever, chills, and back pain 15 minutes after starting a transfusion. Plasma appears red after centrifugation. What is the FIRST action?

A. Continue transfusion slowly
B. Stop transfusion immediately
C. Add saline
D. Send urine sample only

Correct Answer: B. Stop transfusion immediately

Detailed Explanation:
These are classic signs of acute hemolytic transfusion reaction, usually due to ABO incompatibility. The first and most critical action is to stop the transfusion immediately to prevent further hemolysis and possible renal failure or shock. After stopping, maintain IV with saline and notify physician and blood bank. Clerical checks and repeat crossmatch follow. Continuing transfusion could be fatal. Immediate cessation always comes before investigation.

Question 24

Forward typing: Anti-A 4+, Anti-B 0
Reverse typing: A cells 0, B cells 0
Most likely cause?

A. Group A
B. Weak subgroup of A
C. Group AB
D. Technical error only

Correct Answer: C. Group AB

Detailed Explanation:
Forward typing shows A antigen present. Reverse typing shows no antibodies against A or B, meaning patient plasma does not react with either A or B cells. This indicates absence of anti-A and anti-B antibodies — consistent with group AB. In AB individuals, both antigens exist and no reverse antibodies form. ABO discrepancies must be resolved before transfusion to avoid fatal reactions.

Question 25

ABG: pH 7.50, pCO₂ 30, HCO₃⁻ 18
Interpretation?

A. Respiratory alkalosis only
B. Metabolic acidosis only
C. Mixed respiratory alkalosis + metabolic acidosis
D. Normal compensation

Correct Answer: C. Mixed respiratory alkalosis + metabolic acidosis

Detailed Explanation:
High pH indicates alkalosis. Low pCO₂ suggests respiratory alkalosis. However, bicarbonate is also low, which normally indicates metabolic acidosis. Since both abnormalities move pH in opposite directions, this indicates a mixed disorder, not compensation. Mixed acid-base problems are commonly tested in certification exams.

26. Blood Bank Case – ABO Discrepancy Following Massive Transfusion

A 64-year-old trauma patient received 14 units of O-negative packed red blood cells during emergency surgery before his blood type was known.

Forty-eight hours later, a pretransfusion specimen collected for additional blood products shows:

Forward Typing

• Anti-A: Mixed-field (mf)
• Anti-B: 0
• Anti-D: Positive

Reverse Typing

• A₁ Cells: 0
• B Cells: 4+

The patient was previously documented as Group A Rh-positive.

What best explains these current typing results?

A. Cold autoantibody interfering with forward typing

B. Mixed red cell populations from recent massive transfusion

C. Acquired B antigen

D. Rouleaux formation

✅ Correct Answer: B. Mixed red cell populations from recent massive transfusion

Detailed Explanation:

Mixed-field agglutination occurs when two populations of red cells are present. After massive transfusion with Group O RBCs, the patient’s own A-positive cells coexist with donor O cells. This creates mixed-field reactions during forward typing. The reverse type reflects the patient’s plasma antibodies rather than donor RBCs.

This scenario is frequently encountered in trauma centers and is considered high-yield for certification exams.

27. Chemistry Instrument Troubleshooting

Morning QC produces the following glucose results:

Yesterday’s QC was completely acceptable.

Calibration was performed overnight.

Which is the MOST likely cause?

A. Random pipetting error

B. Calibration shift

C. Reagent deterioration

D. Water contamination

✅ Correct Answer: B. Calibration shift

Detailed Explanation:

All three QC levels demonstrate a similar positive bias, indicating a systematic error rather than random variation. Because calibration occurred overnight, an incorrect calibration factor is the most likely explanation. Random errors rarely affect all control levels equally.

28. Hematology Analyzer Flag Investigation

A CBC analyzer reports:

Hemoglobin: 14.2 g/dL

Hematocrit: 44%

RBC: 2.3 ×10¹²/L

MCV: 191 fL

MCHC: 32

Analyzer Flags:

• RBC Agglutination Suspected
• Review Smear

Peripheral smear demonstrates numerous red cell clumps.

What should the technologist do FIRST?

A. Perform saline replacement

B. Warm the specimen to 37°C and repeat the CBC

C. Report the values

D. Perform manual hematocrit

✅ Correct Answer: B. Warm the specimen to 37°C and repeat the CBC

Detailed Explanation:

Cold agglutinins cause RBC clumping, falsely decreasing the RBC count while increasing the MCV. The first corrective action is warming the specimen before rerunning the analysis.

29. Comprehensive Case

A patient presents with:

• Hemoglobin: 6.9 g/dL
• Platelets: 18 ×10⁹/L
• Creatinine: 3.1 mg/dL
• LDH: Markedly elevated
• Peripheral smear: Numerous schistocytes
• PT: Normal
• aPTT: Normal

Which diagnosis is MOST likely?

A. Disseminated intravascular coagulation

B. Thrombotic thrombocytopenic purpura

C. Hemophilia A

D. Autoimmune hemolytic anemia

✅ Correct Answer: B. Thrombotic thrombocytopenic purpura

Detailed Explanation:

This presentation is classic for TTP:

• Microangiopathic hemolytic anemia (schistocytes, elevated LDH)
• Severe thrombocytopenia
• Acute kidney injury
• Normal PT and aPTT (distinguishing it from DIC)

Recognizing this pattern is critical because TTP is a hematologic emergency that requires urgent plasma exchange. This type of integrated, multi-step interpretation question closely mirrors the style used on the AMT MLT certification exam.

30. Hematology – Distinguishing Iron Deficiency Anemia from Thalassemia Trait

A 24-year-old woman is evaluated for chronic anemia.

CBC results:

• Hemoglobin: 10.8 g/dL
• RBC count: 5.9 × 10¹²/L
• MCV: 64 fL
• RDW: Normal

Peripheral smear shows target cells with mild hypochromia.

Which diagnosis is MOST likely?

A. Iron deficiency anemia

B. β-thalassemia trait

C. Anemia of chronic disease

D. Sideroblastic anemia

✅ Correct Answer: B. β-thalassemia trait

Detailed Explanation:

Although both iron deficiency anemia and β-thalassemia trait produce microcytosis, thalassemia trait typically has:

• Normal or elevated RBC count
• Markedly low MCV
• Normal RDW
• Target cells on smear

Iron deficiency usually presents with a low RBC count and increased RDW.