Malignant external otitis and polymorphonuclear leukocyte migration impairment. Improvement with ascorbic acid.

Malignant external otitis (MEO) is a rare disease due to a Pseudomonas infection of the external ear occurring in an elderly patient with uncontrolled diabetes mellitus. Its high mortality raises the question of an alteration of the defense mechanisms of the body. A 58-year-old man was affected with MEO, and after several months of unsuccessful treatment, a study of the function of his polymorphonuclear neutrophil leukocytes (PMNs) revealed a defect of the migration capability. Ascorbic acid (vitamin C) was proved in vitro to be able to improve the results of the migration test. The patient was treated for one month with ascorbic acid and, parallel to the normalization of the chemotaxis test results, the ear lesions healed. The mechanism of such an alteration of the PMN function, implying several factors (the active infection, old age, and diabetes mellitus), is still unclear. Nevertheless, it is certainly important to test the PMN function in patients with MEO and treat them with immunomodulators.