The mold conundrum in chronic rhinosinusitis: where do we stand today?

Chronic rhinosinusitis (CRS) is an inflammatory disorder affecting the nose and paranasal sinuses. Although bacteria have long been implicated as pathogens in most forms of CRS, fungi may be responsible for some forms. Several recent studies demonstrated that, under optimal conditions, fungi can be identified in the nose and paranasal sinuses of nearly every individual (including all CRS patients). An aberrant immune response to these ubiquitous fungi has been suggested to explain the development of CRS in some individuals. Several mechanisms requiring additional research, including adequate controls, have been proposed and are reviewed in this article. Although preliminary trials suggested that CRS signs and symptoms improve upon treatment with topical and oral antifungal agents, several double-blind, placebo-controlled trials demonstrated the contrary. In the absence of convincing immunologic data and evidence of clinical improvement upon therapy with antifungal agents, the case against fungi remains unproven.