Exophiala dermatitidis

Abstract

Exophiala is a genus comprising several species of opportunistic black yeasts, which belongs to Ascomycotina. It is a rare cause of fungal infections. However, infections are often chronic and recalcitrant, and while the number of cases is steadily increasing in both immunocompromised and immunocompetent people, detailed knowledge remains scarce regarding infection mechanisms, virulence factors, specific predisposing factors, risk factors, and host response. The most common manifestations of Exophiala infection are skin infections, and the most frequent type of deep infection is pulmonary infection due to inhalation. The invasive disease ranges from cutaneous or subcutaneous infection to systemic dissemination to internal organs. The final identification of the causative organism should be achieved through a combination of several methods, including the newly introduced diagnostic analysis, matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry, together with sequencing of the ribosomal ribonucleic acid internal transcribed spacer region of the fungi, and histological and culture findings. Regarding treatment, because anti-infective agents and natural compounds exhibited poor antibiofilm activity, few treatments have ultimately been found to be effective for specific antifungal therapy, so the optimal antifungal therapy and duration of therapy for these infections remain unknown. Therefore, most forms of disease caused by Exophiala dermatitidis require aggressive combination therapies: Both surgical intervention and aggressive antifungal therapy with novel compounds and azoles are necessary for effective treatment.

Sinobronchial Syndrome Patients with Suspected Non-Tuberculous Mycobacterium Infection Exacerbated by Exophiala dermatitidis Infection

“…Furthermore, MALDI-TOF MS has recently been used for the diagnosis of E. dermatitidis in addition to genetic ribosomal DNA internal transcribed spacer (ITS) sequencing. 1 , 4 , 12 This protein level analysis was also used in the present study, providing accurate results. It is rapid and easy and should be very supportive to identify E. dermatitidis in combination with conventional microbiological methods, as in the bacterial identification we previously reported.…”

“…However, the duration of antifungal therapy may be critical, because some cases were reported to be recurrent although the patient received VRCZ for 11 months. 1 , 2 , 4 More than 2 years of treatment may be necessary depending on the patients’ status. 2 Further studies of prolonged therapy are needed.…”

“… 1 Furthermore, an altered immune status is known to affect the progress of infectious diseases, and the number of cases is steadily increasing in both immunocompromised and immunocompetent people. 4 Detailed knowledge regarding infection mechanisms, virulence factors, specific predisposing factors, risk factors, host responses, and treatment methods remains scarce.…”

The Presence of Exophiala dermatitidis in the Respiratory Tract of Cystic Fibrosis Patients Accelerates Lung Function Decline: A Retrospective Review of Lung Function

“…E. dermatitidis rarely causes infection in the immunocompetent patient, but is more prevalent in the immunocompromised and has been identified as both a commensal bystander and important cause of invasive disease [1]. Aside from superficial skin infection, the respiratory system is the most common site of E. dermatitidis infection [3]. Despite this, the pathological mechanism of respiratory infection remains unclear.…”

“…In the CF lung in particular, it is likely that the nutrient-rich, heavy mucous burden within the lung, coupled with inadequate mucociliary clearance promotes fungal growth, whilst the ongoing use of broad-spectrum antimicrobials may positively select fungi through the stifling of the growth of their competitors [4]. However, the variability of morbidity associated with this organism in both the immunocompromised and immunocompetent patient suggest that there is a more complex interaction of virulence factors, risk factors, and host responses at play than wholly the pulmonary-specific CF defects [3]. It is likely that the mode of infection is through respiratory inhalation of this ubiquitous organism.…”