Idiopathic dendriform pulmonary ossification diagnosed by bronchoscopic lung cryobiopsy: A case report.

Dendriform pulmonary ossification (DPO) is a rare condition characterized by heterotopic bone production of unknown origin within the pulmonary tissue. Many cases are asymptomatic with slow progression and are often diagnosed incidentally during autopsy. Thus, only few cases are diagnosed while the patient is still alive since surgical lung biopsy is often needed for pathological diagnosis. This is the case of a 37-year-old man treated at our hospital due to abnormal findings on chest x-ray without any symptoms. His high-resolution computed tomography revealed diffuse reticular shadows and micronodules, consistent with calcification. He underwent transbronchial lung cryobiopsy (TBLC) and was diagnosed with idiopathic DPO based on pathological findings. To our knowledge, this is the first reported case of DPO diagnosed using TBLC. TBLC can be a useful yet minimally invasive diagnostic tool to diagnose DPO and other interstitial lung diseases.