PE26.{10-15,17} | Hemato-Oncology Examination and Investigations — Summary & Reflection

KEY TAKEAWAYS

Key take-aways from this module (PE26.10–PE26.17):

Abdominal examination: Always begin with inspection and Traube's space percussion. Palpate the spleen from the right iliac fossa, moving diagonally toward the left costal margin; never begin at the costal margin. Measure in centimetres below the costal margin and use Hackett grading.

CBC interpretation: Apply age-appropriate reference ranges. Anaemia cut-offs: <11 g/dL (6 mo–5 yr), <11.5 g/dL (5–12 yr), <12 g/dL (12–14 yr). Key index: high RDW + low MCV = IDA; normal RDW + low MCV = thalassaemia trait. Pancytopenia = exclude aplastic anaemia and leukaemia. Coagulation: prolonged PT + normal aPTT = extrinsic pathway (factor VII); prolonged aPTT + normal PT = intrinsic pathway (haemophilia A/B).

Peripheral smear: Spread at 30–45°, read in single-layer zone. IDA = pencil cells + high RDW; megaloblastic = oval macrocytes + hypersegmented neutrophils (≥5 lobes); spherocytes = hereditary spherocytosis/AIHA (high MCHC); sickle cells = HbSS; target cells = thalassaemia/liver disease; blasts = leukaemia (even 1 blast is an emergency finding). Auer rods = AML.

Haemoglobin electrophoresis: HbA2 >3.5% = beta-thalassaemia trait (correct iron deficiency first). No HbA + HbS dominant = HbSS. Elevated HbF beyond 6 months = thalassaemia major or HPFH.

Bone marrow aspiration: PSIS in children >18 months; anterior tibial plateau in infants <18 months. Aspiration ≤0.5 mL prevents dilution. Proceed under conscious sedation in children.

Referral criteria: Same-day referral: blasts on smear, Hb <6 g/dL with haemodynamic compromise, platelets <10,000/µL, ANC <200/µL with fever, acute splenic sequestration. Elective referral: iron-unresponsive anaemia, confirmed thalassaemia major or HbSS, hereditary spherocytosis with symptoms.

Splenectomy: Indications include hereditary spherocytosis (≥6 yr), thalassaemia major with hypersplenism (≥5–6 yr), chronic refractory ITP (≥5 yr), and acute/recurrent splenic sequestration in HbSS. Mandatory pre-op vaccinations: PCV13, PPSV23, Hib, MenACWY. Post-op penicillin prophylaxis and OPSI education are non-negotiable.

REFLECT

Consider Riya from the opening scenario — the 6-year-old girl with massive splenomegaly, haemoglobin 5.8 g/dL, TLC 78,000/µL with 35% blasts, who presented to a primary care clinic. You have now built the skill-set to manage the entire diagnostic pathway: you can examine the abdomen systematically and quantify her splenomegaly; you can interpret the CBC with its alarming blast count and recognise this as a haematological emergency requiring same-day referral; you can read the peripheral smear and identify the blast morphology; and you understand that haemoglobin electrophoresis, while important later, is not the immediate priority here — the blast cells demand BMA at the tertiary centre before anything else. Reflect on the following:

• Which single clinical finding — physical examination or investigation — was the most decisive in determining that this child needed urgent transfer today rather than outpatient management?
• How would your counselling of Riya's mother differ if the CBC showed microcytic anaemia, normal TLC, and normal platelet count — i.e., a more chronic, less urgent presentation?
• After your residency, when you work at a primary health centre in a district with high thalassaemia prevalence, what system-level change would you advocate for — based on the referral criteria you have learned — to reduce late diagnosis of thalassaemia major in the community?

The competencies in this module are the clinical foundation upon which every haematological diagnosis in children rests. Mastering them is not optional — it is the difference between a child who receives timely curative therapy and one who presents too late.