Primary pulmonary botryomycosis with parietal pleura involvement.

Botryomycosis is a rare chronic suppurative disease characterized by the presence of eosinophilic granules containing the causative bacteria on histological study of an abscess specimen. The majority of cases involve the skin and visceral involvement is rare. A 54-year-old man with primary pulmonary botryomycosis which involved parietal pleura presented with exertional dyspnea for 2 weeks. Echo-guided aspiration of lung mass yielded viridans streptococci and positive Gram stain of the surgical specimen indicated viridians streptococci was the causative pathogen. There was no recurrence during 2 years of follow-up after surgery and antibiotic treatment. Early differentiation of botryomycosis from lung cancer, pulmonary tuberculosis, and actinomycosis is essential.