Pulmonary Alveolar Microlithiasis: An Indolent Disease with Astounding Radiological Findings

Pulmonary Alveolar Microlithiasis is a disorder in which calcospherites composed of calcium and phosphorous accumulate in the alveoli throughout the lung parenchyma leading to a progressive infiltrative lung disease. It can present completely asymptomatically in early childhood, only to end with cor pulmonale in later life. We report two cases- the first, a six-year-old boy who had a strong familial history of lung diseases and presented with a history of chronic cough. No further symptoms were elicited, although two elder familial members had passed away of cor pulmonale in their mid -30s. The other is an eight-year-old boy referred to as a case of “non-responsive pulmonary tuberculosis, diagnosed sans microbiological evidence. Respiratory examination, and growth were normal in both children. Chest X-ray had a typical ‘Stone Lung’ appearance. The clinical findings were in contrast to the radiological picture and hence a CT scan (Chest) was done. On further suspicion, lung biopsy and genetic analysis established the diagnosis of Pulmonary Alveolar Microlithiasis The patients were given supportive treatment and started on oral Etidronate. With an indolent clinical course, Pulmonary Alveolar Microlithiasis poises itself to remain a “missed diagnosis” with eventual poor outcome, unless the paediatrician is vary about the astounding radiological findings, which should immediately prompt towards further workup for the disease.