Marked hypereosinophilia and rash as initial presentation of acute myeloid leukemia with t(8;21)

Excerpt

A 22-year-old woman presented with 1-month history of generalized pruritic dermatoses after taking weight loss supplements. The rash was unresponsive to steroids, and she developed low grade fever and malaise. She had no past history of eczema, allergic rhinitis, or atopy. On examination, there were multiple large, annular, infiltrated plaques with post-inflammatory hyperpigmentation over her arms, torso, and thighs (Fig. 1a, b). A full blood count showed mild anemia (Hb 11.4 g/L), leukocytosis (19.69 × 10⁹/L) with marked eosinophilia (11.95 × 10⁹/L), and moderate thrombocytopenia (68 × 10⁹/L). Skin biopsy revealed eosinophil-rich perivascular infiltrates with no leukemic infiltrates. Peripheral blood film showed dysplastic eosinophils with hyperlobated nuclei, sparse granulation and abnormal blue granules (Fig. 1d–f). Occasional agranular blasts with basophilic cytoplasm were seen (Fig. 1g). The bone marrow aspirate was hypercellular with marked eosinophilia (27% eosinophil precursors) and 9% blasts (Fig. 1c). Flow cytometry detected 9% blasts expressing CD34, CD117, MPO, CD13, CD33 and aberrant CD19. Cytogenetic analysis showed t(8;21)(q22;q22) with no additional abnormalities. c-Kit mutation was negative. Molecular studies did not detect FIP1L1-PDGFRA or BCR-ABL rearrangements.

…