Silicoproteinosis Masquerading as Community-Acquired Pneumonia

Pulmonary alveolar proteinosis is a rare disorder first described in the literature in 1958. It has been associated with numerous causes, including silica exposure,1-4 infection,2 malignancy,2,5 and inhala-tion of assorted irritant dusts or solvents.6 It is a disease process characterized by an accumulation of granular periodic acid-Schiff (PAS)-positive mate-rial in the alveoli. Disruption of type II pneumo-cytes might contribute to the disease process.4 The chest radiograph classically shows bilateral sym-metrical air space disease, although variations have been reported. The clinical symptoms and signs of pulmonary alveolar proteinosis are varied, ranging from asymptomatic to acute respiratory failure. 7 The case described below illustrates the symp-toms of mild silicoproteinosis, a specific variant of pulmonary alveolar proteinosis associated with sil-ica dust exposure and silicate particles in alveolar material. Silicoproteinosis can imitate other pul-monary disease processes, such as community-ac-quired pneumonia. Silicoproteinosis can be due to a unique pathophysiologic insult or a superinfec-tion. Infectious agents include multiple possible organisms, such as Nocardia, staphylococcus, Hae-mophilus injluenzae, mycobacterium, and Cryptococ-CUS. 2,8,9 In addition to the treatment of different infectious causes, recognition of pulmonary alveo-lar proteinosis is essential in its management. Bron-choalveolar lavage is the effective treatment in the acute setting, whereas longer term management includes removing the patient from the inciting exposure and treating residual symptoms support-ively. Case Report A 25-year-old man complained of flu-like symp-toms of diaphoresis, chills, headache, and mini