Pulmonary Fungal Infections in Immunocompetent Patients

Abstract

Fungi are a group of microorganisms encompassing thousands of species, with only a minority causing disease in humans. Fungal pathogens and infections are increasing global public health problems. They are an important cause of opportunistic infections in immunocompromised patients; however, they can also affect immunocompetent individuals. This paper reviews the incidence, clinical features, radiographic manifestations, and pathological findings of major fungal infections in non-immunocompromised patients. Only a restricted subset of fungi, specifically the endemic dimorphic fungi, selected Aspergillus manifestations, and Cryptococcus gattii are consistently associated with pulmonary infection in immunocompetent individuals. Endemic mycoses are determined by their geographic distribution, which makes it necessary to consider the diagnosis when pulmonary infection occurs in endemic areas. However, their clinical and radiological manifestations are frequently nonspecific. On the other hand, other fungi, mainly Aspergillus spp. are involved in a variety of diseases, including allergic bronchopulmonary aspergillosis, which is frequently diagnosed based on imaging criteria, and a series of conditions in the spectrum of chronic aspergillosis, including simple aspergilloma, chronic cavitary pulmonary aspergillosis, chronic fibrosing pulmonary aspergillosis, subacute invasive pulmonary aspergillosis, and aspergillus nodules.