A Case of Pulmonary Mycetoma Caused by Paecilomyces variotii

Abstract

Fungal infections caused by Paecilomyces species are rare. Although most cases of human infection occur in immunocompromised patients, this species is also being increasingly recognized as a pathogen in immunocompetent individuals. Paecilomyces variotii and P. lilacinus are the most common pathogens in humans. P. variotii infection usually manifests as peritonitis, pneumonia or endophthalmitis. We present the case of an 84-year-old immunocompromised patient with interstitial lung disease, who developed pulmonary mycetoma with isolation of P. variotii in bronchoalveolar lavage fluid culture. We found one similar case in the literature, but Paecilomyces species was not identified. Therefore, this is the first described case of pulmonary mycetoma caused by P. variotii.

Learning points: Paecilomyces are rare causes of fungal infection in humans and occur more frequently in immunocompromised patients.Paecilomyces variotii is one of the most common pathogens of this species and is associated with peritonitis, pneumonia, osteomyelitis, endophthalmitis and fungaemia.To the date, pulmonary mycetoma caused by P. variotii has been described in only one patient in the literature.

Keywords: Paecilomyces variotii; immunosuppression; interstitial lung disease; mycetoma.

Figure 1

Initial chest CT scan revealing interlobular and intralobular septal thickening predominantly in a basal subpleural location

Figure 2

Chest radiograph showing a bilateral reticular pattern predominantly involving the lower lung zones and subpleural lung regions, suggestive of extensive fibrosis

Figure 3

Follow up chest CT scan showing extensive lung fibrosis with multiple cystic lesions, some of which have a typical air-crescent sign suggestive of mycetoma (arrow)