Defective monocyte oxidative metabolism in a child with non-pneumonic legionellosis.

A case of non-pneumonic legionellosis with gastrointestinal manifestations is described in a 13-year-old boy without premorbidity. A selective defect in monocyte oxidative metabolism was found and consistently demonstrated throughout the following year. We suggest that the observed monocyte deficiency may have facilitated the development of legionnaires disease and that otherwise normal monocyte function may have contributed to the favourable course of disease.