Disseminated Cryptococcus gattii infection preceding onset of pulmonary alveolar proteinosis

Abstract

A 50-year-old immunocompetent man presented with intracranial space-occupying lesions and a right lung mass. This was found to be disseminated Cryptococcus gattii infection. Following 15 months of anti-fungal therapy, imaging showed reduction in the size of the pulmonary cryptococcoma and new multi-lobar ground-glass opacities interspersed with a crazy-paving pattern. Surgical lung biopsy was performed after bronchoscopic evaluation was non-yielding. Histology showed intra-alveolar accumulation of foamy macrophages and airspaces containing periodic acid Schiff-positive amorphous eosinophilic material with strong immune positivity for surfactant A, consistent with a diagnosis of pulmonary alveolar proteinosis (PAP). The majority of adult-onset PAP is due to the presence of anti-granulocyte macrophage colony-stimulating factor antibodies. Opportunistic fungal and mycobacterial infections are known to occur in these patients due to alveolar macrophage and neutrophilic dysfunction. The onset of PAP may occur concurrently with, or be temporally distinct from, opportunistic infections. For patients with respiratory failure, whole lung lavage is a therapeutic strategy.