Ten-Year Experience of Cutaneous and/or Subcutaneous Infections Due to Coelomycetes in France

Abstract

Background. Coelomycetes are rarely but increasingly reported in association with human infections involving mostly skin and subcutaneous tissues, both in immunocompetent and immunocompromised patients. Coelomycetes constitute a heterogeneous group of filamentous fungi with distinct morphological characteristics in culture, namely an ability to produce asexual spores within fruit bodies. Methods. We included all cases of proven primary cutaneous and/or subcutaneous infections due to coelomycetes received for identification at the French National Reference Center for Invasive Mycoses and Antifungals between 2005 and 2014. Eumycetoma, chromoblastomycosis, and disseminated infections were excluded. Results. Eighteen cases were analyzed. The median age was 60.5 years. In all cases, patients originated from tropical or subtropical areas. An underlying immunodepression was present in 89% of cases. Cutaneous and/or subcutaneous lesions, mainly nodules, abscesses, or infiltrated plaques, were observed in distal body areas. Isolates of different genera of coelomycetes were identified: Medicopsis (6), Paraconiothyrium (3), Gloniopsis (3), Diaporthe (3), Peyronellaea (2), Lasiodiplodia (1). Lesion treatment consisted of complete (10) or partial (2) surgical excision and/or the use of systemic antifungal therapy, namely voriconazole (5) and posaconazole (4). Literature review yielded 48 additional cases of cutaneous and/or subcutaneous infections due to coelomycetes. Conclusions. Infectious diseases physicians should suspect coelomycetes when observing cutaneous and/or subcutaneous infections in immunocompromised hosts from tropical areas; a sequence-based approach is crucial for strains identification but must be supported by consistent phenotypic features; surgical treatment should be favored for solitary, well limited lesions; new triazoles may be used in case of extensive lesions, especially in immunocompromised patients.

Keywords: Medicopsis romeroi; Paraconiothyrium sp; coelomycetes; cutaneous phaeohyphomycosis; subcutaneous abscess.

Figure 1.

Patient 1. (A and B) Painless subcutaneous cyst of the left foot containing a puriform liquid in a 59-year-old woman with polymyalgia rheumatica treated by corticosteroid therapy. (C) Hematoxylin-eosin staining showed a deep dermal abscess mixed with granulomatous inflammation (×40). The black triangle labels the cyst lumen. (D) Hematoxylin-eosin staining (×1000) with high magnification of a multinucleated cell (black star) and pigmented fungal hyphae (black arrows) (×1000). (E) Gomori methenamine silver stain and (F) periodic acid-Schiff staining ([E], ×400; [F], ×1000) revealed globose or elongated septate hyphal elements (black arrows).

Figure 2.

Patient 13. Pigmented infiltrated plaque of the right knee associated with diffuse subcutaneous infiltration in a 62-year-old kidney transplant recipient. (A) Full and (B) close-up views (courtesy of Camille Frances). (C and D) Hematoxylin-eosin staining revealed a dense dermal infiltrate with granulomatous inflammation, associating neutrophils, lymphocytes, epithelioid, and multinucleated cells, as well as pigmented fungal hyphae ([C], ×100; [D], ×400). (E) Periodic acid-Schiff staining showed septate fungal hyphae (×1000). (F) Fontana-Masson staining confirmed the pigmented character of fungal structures (×1000).

Figure 3.

Macroscopic aspect of Medicopsis romeroi on oatmeal agar (OA), 28°C, 14 days (A); immersed pycnidium of strain CNRMA11.1115 on OA medium (B); conidiophores and conidiogenous cells from a pycnidium of M romeroi (C) small, hyaline conidia of Gloniopsis sp strain (D); mature, septate, striated conidia of Lasiodiplodia theobromae species.