Pulmonary Scedosporium apiospermum Infection with Pulmonary Tumorlet in an Immunocompetent Patient

Abstract

Scedosporium apiospermum is an opportunistic fungus that can cause various types of infections, including localized infections and life-threatening disseminated infections, particularly in immunocompromised patients. Treatment is especially challenging due to its multidrug resistance. We herein report the case of a 73-year-old woman who was non-immunocompromised but developed S. apiospermum lung infection and a pulmonary tumorlet. To our knowledge, this is the first report of the coexistence of pulmonary S. apiospermum infection and tumorlet. The lung lesion was successfully treated by surgical excision without any antifungal agents, and no recurrence of the tumorlet or S. apiospermum infection has occurred.

Keywords: Pseudallescheria boydii; Scedosporium apiospermum; fungus ball; pulmonary tumorlet.

Figure 1.

Chest X-ray (A) and contrast-enhanced computed tomography (B) on admission.

Figure 2.

(A) Colony appearance of Scedosporium apiospermum on a PDA plate. After incubation at 30°C for 20 days, the front surface (left panel) and back surface (right panel) of the plate were photographed. (B) A microscopic examination of the slide culture stained with lactophenol cotton blue. Branching spectated hyphae and single oval sessile conidia at the top of conidiophores (×1,000).

Figure 3.

(A) Gross pathology of the right middle lobe. The arrowheads indicate fungus ball-like tissue filling cystic bronchiectasis. (B) The fungus ball was composed of hyphal elements on the left side of the arrows. The arrows indicate bronchial epithelium. No fungal invasion exceeded the bronchial walls. The tumorlet nests are on the right side of the bronchial epithelium (circle), (Hematoxylin and Eosin staining, ×25). (C) Branching and septate hyphae (arrows) and conidia (arrowheads), (Gomori’s methenamie silver, ×400).

Figure 4.

The nodule consists of a uniform population of cells with oval or spindle nuclei. Rosette formation is evident (A, Hematoxylin and Eosin staining, ×200). Strongly positive immunostaining for Chromogranin A (B, ×100), Synaptophysin (C, ×200) and CD 56 (D, ×100) was observed in the carcinoid tumorlet.