Subcutaneous phaeohyphomycosis and nocardiosis in a kidney transplant patient

Dematiaceous fungal infections in solid organ transplantation: systematic review and bayesian meta-analysis

BACKGROUND

Dematiaceous fungi cause a number of infectious syndromes referred to as phaeohyphomycosis among both immunocompetent and immunocompromised hosts. We performed a systematic review to characterize these infections in solid organ transplant recipients (SOTR).

METHODS

We searched PubMed database (last searched 1/6/2022) for English-language reports on dematiaceous fungal infections in SOTR. Included reports needed individualized demographic, treatment, and outcome data; pediatric reports were excluded. A universally applicable bias assessment was performed on reports. Models for infection type and outcome were created using the Bayesian paradigm.

RESULTS

We included 149 reports on 201 cases of dematiaceous fungal infections in SOTR. The mean age was 54 years, 72% were men, and kidney recipients accounted for 61% of cases. Skin and soft tissue infection (SSTI) was the most common infectious syndrome (73%). Death from infection occurred in 7% of cases (14/201), with disseminated (32%) cases having the highest mortality. Our model for infection type predicted the relative probability of central nervous system infection to be highest in liver recipients. Across all transplant types, higher relative probabilities of disseminated and pulmonary infections occur in the early post-transplant period, and the predicted probabilities for these infection types decreased after 100 months post-transplantation.

DISCUSSION

We identified SSTI as the most common dematiaceous fungal infections in SOTR. Disseminated infections carried the worst prognosis. The evidence in this review is limited by the heterogeneity of included cases. No funding source was used, and this review's protocol was not registered. This article is protected by copyright. All rights reserved.

Case for diagnosis. Subcutaneous phaeohyphomycosis

Subcutaneous phaeohyphomycosis is an infection caused by dematiaceous fungi which mainly affects immunosuppressed patients. We report a case of subcutaneous phaeohyphomycosis on the back of the left hand in a kidney transplant patient who had been taking prednisone, tacrolimus, and azathioprine daily for 3 years.

Melanized fungi in human disease

Melanized or dematiaceous fungi are associated with a wide variety of infectious syndromes, including chromoblastomycosis, mycetoma, and phaeohyphomycosis. [corrected]. Many are soil organisms and are generally distributed worldwide, though certain species appear to have restricted geographic ranges. Though they are uncommon causes of disease, melanized fungi have been increasingly recognized as important pathogens, with most reports occurring in the past 20 years. The spectrum of diseases with which they are associated has also broadened and includes allergic disease, superficial and deep local infections, pneumonia, brain abscess, and disseminated infection. For some infections in immunocompetent individuals, such as allergic fungal sinusitis and brain abscess, they are among the most common etiologic fungi. Melanin is a likely virulence factor for these fungi. Diagnosis relies on careful microscopic and pathological examination, as well as clinical assessment of the patient, as these fungi are often considered contaminants. Therapy varies depending upon the clinical syndrome. Local infection may be cured with excision alone, while systemic disease is often refractory to therapy. Triazoles such as voriconazole, posaconazole, and itraconazole have the most consistent in vitro activity. Further studies are needed to better understand the pathogenesis and optimal treatment of these uncommon infections.

Deep dermatophytosis caused by Trichophyton rubrum with concomitant disseminated nocardiosis in a renal transplant recipient

Deep dermatophytosis and nocardiosis are uncommon infections. This article describes a patient who was immunosuppressed with deep dermatophytosis caused by Trichophyton rubrum and concurrent disseminated nocardiosis. The infections occurred 16 years after the patient underwent renal transplantation, and may have been related to tacrolimus therapy.

Primary cutaneous fungal infections in solid organ transplantation: a case series

Cutaneous fungal infections in solid-organ transplant patients present in a variety of nonspecific ways, requiring a high index of suspicion to diagnose correctly. In the present series of four transplant recipients, subsequent primary cutaneous fungal infections presented as papules, plaques, ulcers and subcutaneous nodules. Transplantations included one cardiac, two renal and one renal-pancreatic transplant. Fungal infections were limited to the skin; there was no evidence of disseminated disease in any case. The pathogens isolated were Scedosporium apiospermum (Pseudallescheria boydii), Alternaria species, Aspergillus fumigatus, and a coelomycete in the Coniothyrium-Microsphaeropsis complex of dark molds. Individuals were successfully treated with surgical debridement, antifungal agents, and reduction of immunosuppressive therapy. All patients and allografts survived. Accurate diagnosis, aggressive surgery and appropriate antifungal therapy, combined with close outpatient follow-up, optimize the likelihood of a cure in a transplant population.

Fungal skin infections in organ transplant recipients

Transplantation is now currently and increasingly performed for the treatment of various acute and chronic diseases. Today the kidney, heart, lung, heart-lung, liver, pancreas, kidney-pancreas, small bowel and bone marrow are being transplanted. The immunological status of patients receiving such transplants exposes them to the risk of developing bacterial, viral and fungal infections. The etiological agents of mycotic diseases involving the skin of transplant recipients range from the common dermatophytes through yeasts such as Candida spp., Malassezia spp. and dimorphic fungi to the emerging molds Fusarium spp. and Pseudallescheria boydii. The very wide spectrum of fungi causing cutaneous disease produces equally varied clinical aspects. Lesions may be typical, but are very often aspecific or ambiguous. Cutaneous lesions may be the sign of a trivial mycotic disease or the marker of a disseminated, potentially lethal fungal illness, so great attention should be given to their early recognition. Cutaneous manifestations due to Candida spp., Aspergillus spp., dematiaceous fungi and Pityrosporum folliculitis are usually observed early after transplant, cryptococcosis more than 6 months later, while the frequency of dermatophytoses increases as time goes by. Coccidioides immitis, Histoplasma capsulatum and Blastomyces dermatitidis may appear any time after transplantation. The management of the more severe forms of cutaneous mycosis in transplant recipients is difficult. Besides the fact that early recognition is not easy, there are also problems regarding the effectiveness and the toxicity of the therapy and drug-drug interactions. Prophylactic measures to avoid fungal contamination must be performed during hospitalization; patients should be taught how to avoid contamination, not only during the first period after transplantation, when high dosage immunosuppressive drugs are given, but also later when a normal lifestyle is resumed.