Atypical mycobacterial infection complicating mineral oil pneumonia.

Two patients had pulmonary infections with atypical mycobacteria superimposed on mineral oil pneumonia. In both cases, long-standing laxative use and neurological disorders led to development of the lipid pneumonia. The pathogenicity of the rapidly growing mycobacteria causing infection in the two patients is apparently enhanced by the presence of mineral oil, a relationship supported by experimental studies. The clinical diagnosis of both atypical mycobacterial infection and mineral oil pneumonia may be difficult, but the presence of one should suggest the possibility of occurrence of the other.