14-month old boy with abrupt-onset petechiae and bruising

A healthy 14-month-old boy presented with a 2-day history of widespread petechiae and bruising. Parents were originally from East Asia, and the boy was born in the UK. He was clinically well with no organomegaly. He had a normal birth history. Newborn bloodspot screening performed on day 5 of life was normal. He had a full and varied diet; thriving with height and weight between 75th and 91st centiles. Examination was otherwise unremarkable. Initial blood results were: haemoglobin 87 g/L (normal range (NR) 113–141), platelets 22×109/L (NR 150–450×109), mean cell volume 54.4 fL (NR 71–85), mean cell haemoglobin 14.1 pg (NR 23–31), reticulocytes 2.1% (NR 0.5–1.5), normal biochemistry, inflammatory markers and coagulation screen. Iron studies: iron 15 µmol/L (NR 13–31), transferrin 273 mg/dL (NR 170–370), total iron binding capacity serum 61 µmol/L (NR 45–73) and iron saturation 25% (NR >16). Figure 1 Blood film. Figure 2 Chromatogram. Figure 3 Annotated blood film. Blood film microscopy (figure 1) and haemoglobin electrophoresis (figure 2) were performed. Leucocyte immunophenotyping was normal. What does the blood film show? What is the most likely diagnosis? 1. Thrombocytopaenia and iron deficiency anaemia 2. Thrombocytopaenia and thalassaemia 3. Bone marrow failure 4. Haemolytic anaemia How should the patient be managed? Answers can be found on page 2 . ### Answer to question 1 #### Short answer Anisopoikilocytosis (variation in size and shape), including tear drop poikilocytes (green arrows), microcytic, hypochromic red cells and target cells (red arrows) (figure 3). Platelets are seen (blue arrows) but …