Superoxide anion hyperproduction by neutrophils in a case of myelodysplastic syndrome. Association with Sweet's syndrome and interstitial pneumonia.

The complication of Sweet's syndrome and interstitial pneumonia occurred in a patient with myelodysplastic syndrome. Superoxide anion production by the patient's neutrophils was considerably higher than that by neutrophils obtained from normal controls after stimulation with opsonized zymosan, phorbol myristate acetate, or myristic acid. Prednisone, which a potent inhibitor of superoxide anion production by neutrophils, dramatically improved the skin and pulmonary lesions, suggesting that they were parts of the same clinical spectrum associated with the superoxide anion hyperproduction.