Cutaneous alternariosis microscopically mimicking blastomycosis

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.

Computational identification and antifungal bioassay reveals phytosterols as potential inhibitor of Alternaria arborescens

Alternaria arborescens is a major pathogen for crops like tomato, tangerine and so on and its control is mostly dependent on the application of chemical agents. Plants as the sources of natural products are very attractive option for developing eco-friendly and natural antifungal agents. In this study, we modeled three-dimensional structure of chorismate synthase (CS) enzyme from A. arborescens. Docking studies of phytosterols, namely, γ-sitosterol and β-sitosterol, with CS showed them to be potential inhibitor of CS. To explore the stability and conformational flexibility of all the AaCS complex systems, molecular dynamics simulations were performed. None of the putative inhibitors as well as β- and γ-sitosterol showed interaction with the FMNH₂ binding pocket of the tomato CS (major host of A. arborescens) indicating their suitability as antifungal compounds inhibiting the shikimate pathway without causing any harm to the host. An in vivo antifungal bioassay showed a significant reduction in fungal growth in the presence of β-sitosterol (500 ppm) which resulted in ∼23% and ∼17% reduction in fungal fresh and dry weight, respectively, at 8 days after inoculation. This study provides experimental evidence establishing natural sterols like β-sitosterol can be useful in curbing A. arborescens damage in an eco-friendly manner.Communicated by Ramaswamy H. Sarma.

Iatrogenic immunosuppression may favour Alternaria skin lesion flares

Alternaria spp may cause opportunistic mycoses in the skin after cutaneous inoculation or through blood dissemination in immune-suppressed patients. Here, we describe a case of cutaneous infection with Alternaria spp in a 62-year-old man, presenting with multifocal papules and erythematous nodules involving distal limbs bilaterally. The absence of inflammatory bowel disease was confirmed by a gastroenterologist. The patient was under treatment for uveitis of unknown origin with immunosuppressive doses of cyclosporin and prednisolone for approximately 3 months. The diagnosis was based on clinical signs, demonstration of fungal elements in skin biopsies and deep fungal culture. Complete clinical remission was achieved by oral and systemic treatment with antifungal drugs. However, because cessation of the immunosuppressive medication was not possible, his clinical history was characterised by multiple flares requiring each time oral and intravenous antifungal treatment.

Cutaneous alternariosis in a renal transplant patient successfully treated with posaconazole: Case report and literature review

Cutaneous alternariosis is an uncommon fungal infection that most commonly presents in organ transplant patients on immunosuppressive therapy. There are no clinical trials or guidelines to guide treatment of this condition, however itraconazole is the most commonly used antifungal in published cases. Here we report on a case of cutaneous alternariosis in a renal transplant recipient treated with a newer antifungal, posaconazole. A review of published reports of cutaneous alternariosis since 2008 is also discussed.

Cutaneous blastomycosis: a clue to a systemic disease

A 55-year-old male presented with back pain and slightly tender annular plaques with central ulceration on his face. A skin biopsy revealed scattered yeast with broad based buds. A CT scan of the abdomen revealed a pathologic T12 fracture. Tissue obtained from the spine confirmed budding yeasts. The patient was diagnosed with disseminated blastomycosis. The patient was treated with amphotericin and itraconazole and completely recovered.