Pulmonary Alveolar Microlithiasis

Abstract

Pulmonary alveolar microlithiasis is a rare pulmonary disorder of unknown etiology characterized by intra-alveolar development and deposition of microliths or calcispherytes consisting of calcium phosphate. Approximately 400 cases of this rare disorder have been described in the literature. The age range of patients is from newborn to 80 years, with a mean age at diagnosis of about 35 years. No sexual predominance has been noted. In about half of the reported cases, a familial pattern has been found, with the disease usually affecting the siblings. The progression of the disease is generally very slow, some patients having been followed up for more than 30 years without evidence of change. Pulmonary function studies demonstrate a tendency toward a restrictive pattern. Chest roentgenography, high-resolution computed tomographic chest scan, and technetium-99m lung scan are useful in the diagnosis. A definitive diagnosis can be established by bronchoalveolar lavage or lung biopsy. There is no known therapy for this unusual disorder. In patients who develop progressive respiratory insufficiency and cor pulmonale, lung transplantations have been performed.

Pulmonary alveolar microlithiasis: two case reports and review of the literature

“…The disease is usually discovered from birth up to 40 yrs of age, and is mostly diagnosed incidentally during pulmonary radiography of the chest for other reasons [7,8,12,19]. Many patients have no clinical symptoms, and most of the cases either have normal pulmonary function or a mild restrictive pattern [11,19].…”

“…Many patients have no clinical symptoms, and most of the cases either have normal pulmonary function or a mild restrictive pattern [11,19].…”

“…In some patients, the disease remains static, while it in others worsens over time, progressing into pulmonary fibrosis, respiratory failure and cor pulmonale [12,19,20].…”

“…Although the SLC34A2 gene is involved in phosphate homeostasis in several organs, including the lung [14,15], blood levels of calcium and phosphate are usually normal in PAM [2,19,22,23]. However, one case has been reported with slightly low normal serum phosphate and low 24-h urinary excretion of phosphate and calcium [18], and another with serum calcium below normal [24].…”

CD8+ T-cell alveolitis in familial pulmonary alveolar microlithiasis

“…The relationship between this immune dysregulation and genetic background in pulmonary alveolar microlithiasis warrants further investigation. KEYWORDS: Bronchoalveolar lavage, diffuse lung disease, pulmonary alveolar microlithiasis, T-CD8 lymphocytes, T-receptor repertoire P ulmonary alveolar microlithiasis (PAM) is a rare diffuse lung disease characterised by progressive intra-alveolar formation and accumulation of tiny, rounded corpuscles called microliths [1]. The analysis of reported cases reveals that the disease is prevalent amongst family units with a high rate of consanguinity among the parents of affected individuals [2,3], suggesting the hypothesis of the role of genetic factors in causing PAM [4].…”