AUTHOR=Di Somma C. , Annunziata A. , Coppola A. , Polistina G. E. , Marotta A. , Fiorentino G. TITLE=Pulmonary ossification: a case report JOURNAL=Frontiers in Medicine VOLUME=Volume 12 - 2025 YEAR=2025 URL=https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2025.1615806 DOI=10.3389/fmed.2025.1615806 ISSN=2296-858X ABSTRACT=Pulmonary calcification and ossification are uncommon findings characterized by the deposition of calcium salts or bone tissue in the lung, generally associated with chronic kidney disease, hyperparathyroidism, and several other causes (1). Ossification is bone formation without or with marrow elements in the lung (1). In some patients, a new entity of subclinical primary hyperparathyroidism has been detected, characterized by persistently elevated parathyroid hormone concentration and normal serum calcium level, usually asymptomatic (2). CT scan is the standard method for detecting calcification and ossification. Radiological presentation on CT is characterized by round or lobulated nodules (3). Follow-up consists of monitoring lung images and lung function to assess disease progression. It suggests an annual CT scan. In this case, we presented a rare association of dendriform ossification with normocalcemic hyperparathyroidism, in particular, in a patient with pulmonary ossification, subclinical primary hyperparathyroidism, and diffuse calcifications.