The way to the diagnosis of alveolar proteinosis: what is decisive?

In this article, we describe the course and diagnosis of pulmonary alveolar proteinosis (PAP) based on two cases from our practice. The first case is a 52-yearold woman, the second a 34-year-old man. Both referred patients were examined by a pulmonologist for interstitial lung disease, in the first case also with transition to pulmonary fibrosis. As part of the differential diagnosis, these patients were hospitalized at the NÚTPCHaHCH in Vyšné Hágy. Chest X-ray showed diffuse bilateral lung infiltrates, in the first patient locally confluent. Chest CT showed parenchymal involvement of the lungs with bilateral ground-glass opacities with thickened interlobular septa (crazy paving). Bronchoscopic examination was performed in both patients with bronchoalveolar lavage, which had a characteristic milky-glazed appearance. Videothoracoscopic lung biopsy was additionally indicated and histopathologically there were pulmonary alveolar proteinosis confirmed. Therapeutically, the patients underwent large volume lung lavage, with clinical condition improvement, including radiological findings improvement. We point out the basic pillars of the diagnosis of pulmonary alveolar proteinosis, which are the pattern of pulmonary involvement in the radiographic and CT (or HRCT) images, the characteristic appearance of the bronchoalveolar lavage fluid, and additionally also the histopathologic pattern of pulmonary involvement in this disease. We emphasize the need for centralized management of patients with lung diseases, which is particularly urgent in cases of rare diseases, where it provides rapid availability of all relevant diagnostic and therapeutic options, including large-volume lung lavage.