Anaemia: diagnostic approach — viva

Opening

Examiner: The haemoglobin is 82 g/L. How do you start? [1]

Candidate: First I confirm the child is stable, because severe anaemia can present with cardiac compromise. Then I classify the count rather than jump to a diagnosis. I ask two questions: what is the mean corpuscular volume, and is the reticulocyte count appropriate? Those two answers, plus a peripheral film, organise almost every case before any second-line test. [1] [3]

Branch A — Microcytic, low reticulocyte

Examiner: The MCV is 64 femtolitres, reticulocytes low, ferritin low. [1]

Candidate: That sits in the microcytic, production-limited cell, and low ferritin confirms iron deficiency. I correct the driver such as excess cow's milk, start oral elemental iron at 3 to 6 milligrams per kilogram per day, and plan a response check expecting a reticulocyte rise first. I still keep the microcytic mimics on the differential. [1]

Branch B — Microcytic, normal ferritin

Examiner: Iron studies are normal, red cell count is high, ancestry suggests trait. [4]

Candidate: I consider thalassaemia trait and add a haemoglobinopathy screen, because trait mimics iron deficiency but does not need iron unless deficiency coexists. I would not commit this child to indefinite iron. I also keep anaemia of inflammation and lead on the list. [4] [6]

Branch C — Macrocytic

Examiner: Now the MCV is 106 femtolitres with hypersegmented neutrophils. [5]

Candidate: That points to megaloblastic anaemia from B12 or folate deficiency. I confirm with serum B12 and folate, look for malabsorption or pernicious anaemia, and replace the missing vitamin. I also remember that a marked reticulocytosis from active haemolysis can raise the volume, so I read the reticulocyte count. [5]

Branch D — Cytopenias and fever

Examiner: Platelets and neutrophils are now low, and the child is febrile. [2]

Candidate: This is a suspected marrow pathology or malignancy, and it is a time-critical infection risk. I treat neutropenic fever with empirical broad-spectrum antibiotics, arrange same-day film and senior haematology review, and prepare for marrow examination with cytogenetics. I would not trial iron. [2]

Close

Examiner: Give me your disposition principle. [2]

Candidate: Stable, single-lineage, low-risk children can be worked up as outpatients with a named review and safety-net. Children with severe symptoms, active haemolysis, multi-lineage cytopenias, fever or suspected marrow failure need same-day escalation, with diagnostic samples drawn before transfusion whenever it is safe. [2]