Diagnosis and Discussion:
Based on the above clinical, microbiological and pathological
findings, and the absence of identifiable associated diseases,
including infections of the lung, haematologic malignancies, or
exposure to inorganic dust and chemicals, a diagnosis of primary
pulmonary alveolar proteinosis was made.
The light and electron microscopic features are characteristic of pulmonary alveolar proteinosis. In biopsies of this type, a number of agents might be responsible for the alveolar infiltrate and electron microscopy is a rapid way of confirming the characteristic phospholipoproteinaceous secretory material of this rare condition. Ultrastructurally, this material (deranged production and/or catabolism of surfactant) forms myelin-like structures, i.e., round multilayered bodies, embedded within a finely granular background material.
Pulmonary alveolar proteinosis is a rare disease of unknown etiology and variable natural history, which has been associated with a myriad of diseases and disorders (1-3). Most patients present with dyspnea and cough with a small number reporting hemoptysis and chest pain. The diagnosis is usually established by either transbronchial or open-lung biopsy. If the clinical situation warrants it, treatment consists of unilateral or bilateral (whole) lung lavage (1-3). Grossly, the bronchoalveolar lavage fluid has a characteristic milky appearance and considerable sediment. Smears of the fluid sediment show a basophilic, PAS-positive, granular debris with cholesterol crystals and a few alveolar macrophages (2). Ultrastructural examination of the PAS-positive globules seen in smears has shown these to be the multilamellated structures, so it has been suggested that the amorphous granules are themselves diagnostic (3). Pulmonary alveolar proteinosis can occur in both a congenital and infantile form (4).
References:
