Disseminated Blastomycosis With Pulmonary, Cutaneous, and Splenic Involvement in a Construction Worker: A Case Report

Blastomycosis is a systemic fungal infection that is caused by Blastomyces dermatitidis or Blastomyces gilchristii. Although the lungs are the primary site of infection, blastomycosis can disseminate to the skin, bones, genitourinary system, and, rarely, visceral organs such as the spleen. Occupational exposure to soil and decaying matter, particularly in construction workers, increases the risk of blastomycosis infection. A 40-year-old male presented with a progressively enlarging right facial lesion, which initially appeared as a small papule. The lesion had gradually increased in size and pain over several months and failed to respond to antibiotics. Notable symptoms include generalized fatigue, low mood, intermittent morning headaches, confusion, poor appetite with weight loss, intermittent night sweats, and joint pain. The diagnostic workup included imaging findings of an exophytic skin lesion arising from the right cheek, pulmonary micronodules and consolidation, and splenic changes. Serum Blastomyces antigen testing was positive, fungal culture of tissue from the facial lesion grew Blastomyces dermatitidis, and histopathologic examination demonstrated granulomatous inflammation with broad-based budding yeast within the dermis, supporting the diagnosis of disseminated blastomycosis. Liposomal amphotericin B induction therapy was initiated, and the facial lesion improved. The patient was discharged home with a transition to oral itraconazole. This report presents a case of disseminated blastomycosis involving the lungs, skin, and spleen in an immunocompetent individual. High index of suspicion and recognition of cutaneous lesions in the context of occupational and environmental risk factors for blastomycosis enable early diagnosis and treatment.