Acute hemolytic anemia induced by a pyrazolonic drug in a child with glucose-6-phosphate dehydrogenase deficiency.

In a 36-month-old child a severe hemolytic anemia occurred after the administration of a pyrazolonic drug. Erythrocyte glucose-6-phosphate dehydrogenase activity was absent in the patient. Intermediate enzymatic levels were demonstrated in the mother and in the maternal grand-mother with a corresponding erythrocyte mosaicism at the methemoglobin elution test. Some cells showed Heinz bodies and peculiar changes in the morphology in the initial phase of the crisis. There is no mention in the literature of a hemolytic action of this drug.