Lung, pleural and colon actinomycosis in an immunocompromised patient: a rare form of presentation.

Actinomycosis is caused by gram-positive filamentous organisms of the genus Actinomyces, which may spread through trauma. Most commonly, it is a cervicofacial disease due to dental infection or a thoracic disease secondary to aspiration of foreign bodies. Primary abdominal infection usually follows some form of mucosal disruption. Any organ of the human body may be involved so that a wide range of symptoms may be present. We report a rare form of actinomycosis involving the lung, pleura and colon concomitantly in an immunocompromised patient. A fine needle aspiration from a lung lesion detected the characteristic sulfur granules, and a pleural effusion culture confirmed the diagnosis. Clinical manifestations and treatment are discussed. Actinomycetes are rarely opportunistic agents in immunocompromised patients; thus the disease deserves special attention in those patients.