Dendriform Pulmonary Ossification, a Form of Diffuse Pulmonary Ossification: Report of a 26-Year Autopsy Experience

Abstract

Abstract Context.—Dendriform pulmonary ossification (DPO) is an uncommon form of diffuse pulmonary ossification that typically affects the pulmonary interstitium in a setting of interstitial fibrosis. Objective.—To determine the incidence and characteristics of DPO and correlate the clinical, radiographic, and pathologic features in order to better understand its pathogenesis and behavior and facilitate proper therapy. Design.—Adult autopsies performed at a tertiary care center from 1978 to 2004 were reviewed to identify cases of DPO. Clinical, radiographic, and pathologic findings, including ultrastructural studies in select cases, were analyzed and correlated. Results.—Eight cases of DPO were identified from 1393 adult autopsies. None of the cases was diagnosed antemortem. The prevalence of DPO was 0.5%, and the incidence was 0.28 cases per year. Most patients had a history of chronic lung disease, and all were 65 years of age or older. Conclusions.—Dendriform pulmonary ossification is an uncommon and unusual entity seen incidentally at autopsy and associated with chronic lung disease. It is well demonstrated in postmortem examination, confirmed by microscopy and ultrastructural study, but rarely diagnosed and virtually never considered clinically. Clinical diagnoses include bronchiectasis and interstitial pneumonitis based on radiographic evidence. With its associated radiographic/pathologic findings, DPO should be considered in the differential diagnosis of chronic lung disease.