Case report: Disseminated Scedosporium apiospermum infection with invasive right atrial mass in a heart transplant patient

Abstract

Scedosporium apiospermum associated endocarditis is extremely rare. We report a case of a disseminated S. apiospermum infection with an invasive right atrial mass in a 52-year-old male, 11 months after heart transplantation, referred to our institution for an endogenous endophthalmitis with a one-month history of diffuse myalgias and fatigue. The patient had been supported two times with extracorporeal membrane oxygenation (ECMO) during the first three postoperative months. The echocardiography on admission revealed a mass in the right atrium attached to a thickened lateral wall. The whole-body [¹⁸F]FDG PET/CT revealed systemic dissemination in the lungs, muscles, and subcutaneous tissue. Blood cultures were positive on day three for filamentous fungi later identified as S. apiospermum. The disease was refractory to a 3-week dual antifungal therapy with voriconazole and anidulafungin in addition to reduced immunosuppression, and palliative care was implemented.

Keywords: Lomentospora prolificans; PET/CT; Scedosporium apiospermum; heart failure; heart tranplantation; infective endocarditis; mycoses.

FIGURE 1

Painful purplish cutaneous nodules (A), pathology examination with Periodic Acid Schiff coloration 10x (B), and colorations with GROCOTT stain of cutaneous nodules showing regular septate filaments connected with 45-degree divisions 10x (C) and 40x (D).

FIGURE 2

Right atrium mass (15 × 18 mm) with thickened lateral wall without associated tricuspid valve anomalies as shown in transthoracic echocardiography [green arrow, Panel (A)] and transesophageal echocardiography [green arrow, Panel (B)].

FIGURE 3

¹⁸F-fluodeoxyglucose ([¹⁸F]FDG) Positron emission tomography (PET)/computed tomography angiography (CTA) findings. Left: Maximum intensity projection image of the whole body showing pathological focal diffuse [¹⁸F]FDG uptake of the trunk as well as the upper and lower extremities. Right: (A) Cardiac CTA showing an heterogeneous mass with irregular margins, in contact with the lateral wall of the right atrium with extension in the pericardial space. (B) Transaxial view of [¹⁸F]FDG PET/CTA showing pathological [¹⁸F]FDG accumulation of the right atrial mass, suggestive of an active infectious process. (C) Transaxial view of [¹⁸F]FDG PET/CTA showing focal subpleural nodules with increase [¹⁸F]FDG accumulation in the left lung, suggestive of septic emboli. (D) Coronal view of [¹⁸F]FDG PET/CT showing focal increased cutaneous and subcutaneous [¹⁸F]FDG accumulation in the proximal part of the lower limbs, suggestive of septic emboli.