[Allopurinol-induced DRESS complicated by hemophagocytic lymphohistiocytosis]

Drug hypersensitivity syndrome is among the most severe drug hypersensitivity reactions and in rare cases it may progress to hemophagocytic lymphohistiocytosis. Herein, we report a case of allopurinol-induced drug reaction with eosinophilia and systemic symptoms complicated by hemophagocytic lymphohistiocytosis.

An 18-year-old girl presented with maculopapular rash associated with cervical lymphadenopahy appearing 3 weeks after treatment with allopurinol. Her hemodynamic status at admission was unstable. Cutaneous examination revealed an itchy maculopapular rash, which was purpuric at certain sites, together with facial edema. The diagnosis of drug hypersensitivity was suggested and was confirmed by histological examination of a skin biopsy. Allopurinol was stopped. Two weeks later, however, eosinophilia was noted. Further, four days after discontinuation of allopurinol, in view of the laboratory signs of bicytopenia, hyponatremia, hypertriglyceridemia and hyperferritinaemia, as well as the presence of hemophagocytosis in bone marrow, a diagnosis was made of lymphohistiocytosis hemophagocytic syndrome complicating a drug reaction with eosinophilia and systemic symptoms. Moreover, viral serology tests were negative. The patient was given intravenous immunoglobulin and the outcome was good.

The literature contains only very few reports of drug reaction with eosinophilia and systemic symptoms complicated by hemophagocytic lymphohistiocytosis. The incriminated drugs were vancomycin, lamotrigine and phenobarbital. To our knowledge, there has only been one report of allopurinol-induced drug reaction with eosinophilia and systemic symptoms complicated by hemophagocytic lymphohistiocytosis.