A 6-year-old boy has developmental delay, thumb anomalies, radial ray defects, short stature, and pancytopenia. Chromosome breakage analysis shows increased sensitivity to diepoxybutane. Which finding is most likely on his blood film?

• A Macro-ovalocytes with hypersegmented neutrophils
• B Schistocytes with thrombocytosis
• C Macrocytosis with elevated fetal hemoglobin ✓
• D Teardrop cells with leukoerythroblastosis

Explanation

Fanconi anemia is an autosomal recessive DNA repair disorder presenting with congenital radial ray and thumb anomalies plus aplastic anemia, typically in childhood. The smear commonly shows macrocytosis, and HbF is characteristically elevated. Diepoxybutane-induced chromosomal breakage is diagnostic. Leukoerythroblastosis with teardrop cells suggests myelofibrosis, seen in older adults, eliminating D.

Reference: Nelson Textbook of Pediatrics, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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