Spectrum of fungal sinusitis

Fungi are diverse and ubiquitous organisms. Their spores are frequently respired and can be found throughout the nose and sinuses. Generally, the human immune system is naturally equipped to eliminate these airborne invaders; however, in approximately 10% of patients, fungal spores and elements become manifest as disease. The manifestation of disease within the nose and paranasal sinuses varies widely from the benign to the utterly malignant and fatal. Fungal infections of the paranasal sinuses can be broadly divided into two categories based on the histopathological diagnosis of tissue invasion. For the purposes of this chapter, fungal disease is either noninvasive or invasive [1,2]. The primary manifestations of noninvasive disease are the development of fungal balls or allergic fungal sinusitis (AFS). Invasive fungal sinusitis occurs either as an acute, rapidly progressive sinusitis or in a chronic fashion. This chapter outlines the diagnosis and treatment of the various forms of fungal sinusitis. A summary of forms of fungal sinusitis can be found in Table 14.1.