Aplastic Anaemia
Severely hypocellular marrow (<10%) with fat replacement, pancytopenia, and appropriately elevated EPO (compensatory response to anaemia) is the classic picture of aplastic anaemia, typically driven by autoimmune T-cell attack on haematopoietic stem cells.
APLASTIC ANAEMIA
- Definition: Pancytopenia resulting from hypoplasia of the bone marrow
- Classification: Primary (congenital or acquired) or Secondary
Read this in Aplastic Anemia: Causes, Symptoms & Treatment | Hematology
What our notes say
- Severely hypocellular marrow (<10%) with fat replacement, pancytopenia, and appropriately elevated EPO (compensatory response to anaemia) is the classic picture of aplastic anaemia, typically driven by autoimmune T-cell attack on haematopoietic stem cells. (Haematopathology MCQs: Blood Disorders & Anemia Explained)
- This is the opposite picture from aplastic anaemia (hypocellular marrow), a classic exam contrast. (Hematology & Blood Transfusion Pathology: MDS, Stem Cell Transplant)
- Tests useful in the diagnosis of aplastic anaemia include the following, except: (Internal Medicine (MBIM 4100) main exam, Paper One: 3 July 2019)
- Severe aplastic anaemia has a neutrophil count below 0.5 × 10⁹/L. (Internal Medicine (MBIM 4100) main exam, Paper One: 3 July 2019)
- Under-production: iron, folate or B12 deficiency, HIV, TB, chronic kidney disease, malignancy, aplastic anaemia. (Approach to anaemia)
- In a bone marrow biopsy of a patient with aplastic anaemia, you would expect to find: (HEMATOLOGY EOY 2025 — Past Paper Questions & Answers)
Study material on Aplastic Anaemia
- Aplastic Anemia: Causes, Symptoms & Treatment | Hematology
- Haematology Exam 2025: MCQs on Anaemia, Leukaemia & Clotting
- MDS, Myelofibrosis & HLH: Key Blood Disorders Explained
- Haematology End of Year 2025 Past Paper — MKU MBML 3200 Questions & Answers
- Hematopathology MCQs & Essays: MBChB Exam Revision Guide
- Internal Medicine (MBIM 4100) main exam, Paper One: 3 July 2019
- HEMATOLOGY EOY 2025
- Platelet Disorders
- Renal, Liver, Cardiac & Adrenal Function Tests for Year 3
- Haematopathology MCQs: Blood Disorders & Anemia Explained
- Haematology Exam 2025: MCQs on Anaemia, Leukaemia & Clotting
Practice questions on Aplastic Anaemia
Aplastic anaemia is characterized by
- Hypercellular marrow with dyserythropoiesis
- Pancytopaenia with hypocellular (fatty) bone marrow
- Macrocytosis with normal marrow cellularity
- Elevated reticulocyte count
Answer: B. Aplastic anaemia involves destruction or suppression of haematopoietic stem cells, leading to empty fatty marrow and pancytopaenia with low reticulocytes. ---
In a bone marrow biopsy of a patient with aplastic anaemia, you would expect to find
- Hypercellular marrow with many erythroblasts
- Increased megakaryocytes
- Fatty replacement and hypocellularity
- Increased lymphoid follicles
Answer: C. Aplastic anaemia is characterised by marrow hypocellularity with replacement by fat, reflecting stem cell failure. ---
Which of the following is a known cause of aplastic anaemia?
- Vitamin B12 deficiency
- Epstein-Barr virus infection
- Parvovirus B19
- Chloramphenicol use
Answer: D. Chloramphenicol is a classic drug cause of idiosyncratic bone marrow aplasia through direct toxicity to haematopoietic stem cells. ---