A 36-year-old man presented to our hospital because of abnormal findings on chest X-ray, without any symptoms. He was a never-smoker with no family history of lung disease. High-resolution computed tomography showed diffuse reticular shadows and micronodules with calcification (Picture A and B). Bronchoalveolar lavage and transbronchial lung biopsies revealed no abnormality. A surgical lung biopsy was performed, and a pathological examination of the biopsied specimen showed dendriform ossification with mature bone marrow within the lung parenchyma without other diseases (Picture C and D). These observations results in a diagnosis of dendriform pulmonary ossification (DPO). DPO is an extremely rare disease and rarely diagnosed while the patient is alive (1). DPO is classified as idiopathic or secondary. The aetiology of idiopathic DPO is unknown, but secondary DPO is associated with pre-existing lung diseases (2). As our patient had no pre-existing disease, idiopathic DPO was diagnosed. Despite not receiving any treatment, the patient has remained asymptomatic for eight years now.
Picture.
The patient provided his informed consent for the publication of this case.
The authors state that they have no Conflict of Interest (COI).
References
- 1. Lara JF, Catroppo JF, Kim DU, et al. Dendriform pulmonary ossification, a form of diffuse pulmonary ossification: report of a 26-y autopsy experience. Arch Pathol Lab Med 129: 348-353, 2005. [DOI] [PubMed] [Google Scholar]
- 2. Fernández-Bussy S, Labarca G, Pires Y, et al. Dendriform pulmonary ossification. Respir Care 60: e64-e67, 2015. [DOI] [PubMed] [Google Scholar]

