Malacoplakia in childhood. Case report with ultrastructural observations and review of the literature.

Malacoplakia involving the adrenal gland and colon was found in a 6-week-old infant. To our knowledge, this is the first reported instance of adrenal involvement and it occurred in the youngest patient described to have malacoplakia. The adrenal gland was the site of a previous hemorrhage. Ultrastructurally, the cytoplasm of the malacoplakia cells contained numerous granular inclusions within which were tetrad-shaped particles resembling ferritin. A thorough search failed to show the presence of any bacteria. Several recent papers have suggested that malacoplakia represents a morphologic manifestation of altered host macrophage response and that Gram-negative enteric bacilli are the usual specific etiologic agents. The pathologic findings in the present case raise the possibility that the lesion in this instance represents an altered macrophage response to extravasated erythrocytes alone or to erythrocytes and bacteria.