Osteitis and chronic rhinosinusitis: a review of the current literature.

Chronic rhinosinusitis is a common debilitating condition characterized by inflammation of the nose and paranasal sinuses. Osteitis is an associated finding but it is not clear whether it is cause or effect. This review will report on studies that have examined the role of osteitis in CRS, with the ultimate aim of clarifying the definition, pathogenesis and clinical implications of this relatively new clinical entity. Literature searches of Medline, EMBASE and CENTRAL using the search terms osteitis, rhinosinusitis, sinusitis, rhinitis, chronic disease, and recurrence were performed. 21 articles were identified and reviewed. The papers highlighted key pathological features including periosteal thickening, new woven bone formation, bone resorption, fibrosis and inflammatory cell infiltration. Radiological grading systems and basic science research into the role of matrix metalloproteinases and P-glycoprotein were also identified and reviewed.