Allergic aspergillosis of the respiratory tract.

Aspergillus, a genus of spore forming fungi found worldwide, affects the respiratory tract in many ways [1, 2]. The spores of this ubiquitous mould are dispersed by wind in the atmosphere and inhalation is the primary route of access in almost all forms of aspergillosis. The spectrum of Aspergillus-associated respiratory disorders comprises three well defined clinical categories (table 1): allergic manifestations, saprophytic colonisation of the respiratory tract and invasive disseminated disease [1]. Amongst the allergic aspergillosis disorders, allergic bronchopulmonary aspergillosis (ABPA) is the most recognised form. Since it was first described in England, UK, in 1952 [3], it has been documented around the world [4]. Although ABPA and allergic Aspergillus sinusitis (AAS) are mostly encountered in atopic individuals, hypersensitivity pneumonitis can occur in the nonatopic population.