Pulmonary ossification: pathogenesis

• Grant number: 11/21431-4
• Support Opportunities: Regular Research Grants
• Start date: June 01, 2012
• End date: August 31, 2013
• Field of knowledge: Health Sciences - Medicine - Pathological Anatomy and Clinical Pathology
• Principal Investigator: Simone Gusmão Ramos
• Grantee: Simone Gusmão Ramos
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Diffuse pulmonary ossification (DPO) is a rare condition of unknown pathogenesis in which mature bone is found in the pulmonary parenchyma. Most commonly, it affects old-aged men. Patients can be asymptomatic or have minimal complaints, and usually DPO represents an unexplained radiographic finding. Many cases are diagnosed at autopsy. Several predisposing conditions are associated with pulmonary parenchyma calcification with or without ossification, but it may also be idiopathic. Two histological types of pulmonary ossification have been described: (1) a nodular circumscribed form and (2) a dendriform type. The pathogenesis of pulmonary ossification is unknown. Serum calcium and phosphorus levels are usually normal. Growth factors from cells involved in this extracellular matrix formation and resolution of inflammation have been suggested to play a role in this process, but nowadays there are no data proofing it. The aim of this study is to demonstrate if patients with OPD show bone morphogenic protein-2 (BMP-2), a member of the TGF- ß (transforming growth factor) superfamily, and IL-1 ß in higher values when compared with other fibroproliferative diseases of the pulmonary parenchyma, such as BOOP and IPF, using Western blot techniques. These findings could confirm that BMP-2 and IL-1 ß have a fundamental role in the development of heterotopic bone in the pulmonary parenchyma in humans. (AU)