Eosinophilic leukemoid reaction associated with carbamazepine hypersensitivity

Carbamazepine is widely used in the treatment of epilepsy, neuralgic pain, and bipolar affective disorders. Several adverse drug reactions have been described during the course of carbamazepine administration, including exanthemata and hematological reactions. Carbamazepine is one of the common drugs that have been implicated in the etiology of drug hypersensitivity syndrome. A 50-year-old male presented with generalized erythroderma following 10 weeks of ingestion of carbamazepine 200 mg daily for idiopathic epilepsy. His systemic examination was within normal limits. Blood counts revealed marked eosinophilia of 52% (absolute eosinophil count of 10,400 per mm3). Bone marrow aspiration revealed a moderate increase in the eosinophilic series with cells showing normal morphology. The eosinophil counts returned to normal after 2 weeks of oral prednisolone therapy. This case is reported because of its rarity in the Indian medical literature.