Clinical characteristics and epidemiology of pulmonary pseudallescheriasis

Abstract

Background: Some members of the Pseudallescheria (anamorph Scedosporium) have emerged as an important cause of life-threatening infections in humans. These fungi may reach the lungs and bronchial tree causing a wide range of manifestations, from colonization of airways to deep pulmonary infections. Frequently, they may also disseminate to other organs, with a predilection for the brain. In otherwise healthy patients, the infection is characterized by non-invasive type involvement, while invasive and/or disseminated infections were mostly seen in immunocompromised patients.

Aims: We reviewed all the available reports on Pseudallescheria/Scedosporium pulmonary infections, focusing on the geographical distribution, immune status of infected individuals, type of infections, clinical manifestations, treatment and outcome.

Results and conclusions: The main clinical manifestations of the 189 cases of pulmonary pseudallescheriasis reviewed were pneumonia (89), followed by fungus ball (26), and chest abscess (18). Some patients had more than one type of invasive pulmonary manifestations. Among patients with pneumonia, several cases of pneumonia associated with near-drowning (10/89, 11.2%) have also been reported in immunocompetent hosts. Major underlying conditions for non-invasive pulmonary infection were preexisting lung cavities and medical immunosuppression for invasive pulmonary infection. Saprobic airway colonization was mostly seen in patients with mucosal dysfunction, i.e. patients with cystic fibrosis. The mortality rate was closely related to the infection type, being 26.8% in non-invasive type (fungus balls) and 57.2% in invasive type.