Subcutaneous phaeohyphomycosis caused by Phaeoacremonium rubrigenum in an immunosuppressed patient

Phylogenetic Reconstruction of the Calosphaeriales and Togniniales Using Five Genes and Predicted RNA Secondary Structures of ITS, and Flabellascus tenuirostris gen. et sp. nov

The Calosphaeriales is revisited with new collection data, living cultures, morphological studies of ascoma centrum, secondary structures of the internal transcribed spacer (ITS) rDNA and phylogeny based on novel DNA sequences of five nuclear ribosomal and protein-coding loci. Morphological features, molecular evidence and information from predicted RNA secondary structures of ITS converged upon robust phylogenies of the Calosphaeriales and Togniniales. The current concept of the Calosphaeriales includes the Calosphaeriaceae and Pleurostomataceae encompassing five monophyletic genera, Calosphaeria, Flabellascus gen. nov., Jattaea, Pleurostoma and Togniniella, strongly supported by Bayesian and Maximum Likelihood methods. The structural elements of ITS1 form characteristic patterns that are phylogenetically conserved, corroborate observations based on morphology and have a high predictive value at the generic level. Three major clades containing 44 species of Phaeoacremonium were recovered in the closely related Togniniales based on ITS, actin and β-tubulin sequences. They are newly characterized by sexual and RNA structural characters and ecology. This approach is a first step towards understanding of the molecular systematics of Phaeoacremonium and possibly its new classification. In the Calosphaeriales, Jattaea aphanospora sp. nov. and J. ribicola sp. nov. are introduced, Calosphaeria taediosa is combined in Jattaea and epitypified. The sexual morph of Phaeoacremonium cinereum was encountered for the first time on decaying wood and obtained in vitro. In order to achieve a single nomenclature, the genera of asexual morphs linked with the Calosphaeriales are transferred to synonymy of their sexual morphs following the principle of priority, i.e. Calosphaeriophora to Calosphaeria, Phaeocrella to Togniniella and Pleurostomophora to Pleurostoma. Three new combinations are proposed, i.e. Pleurostoma ochraceum comb. nov., P. repens comb. nov. and P. richardsiae comb. nov. The morphology-based key is provided to facilitate identification of genera accepted in the Calosphaeriales.

In Vitro Susceptibility Profiles of Eight Antifungal Drugs against Clinical and Environmental Strains of Phaeoacremonium

In vitro susceptibilities of a worldwide collection of molecularly identified Phaeoacremonium strains (n = 43) belonging to seven species and originating from human and environmental sources were determined for eight antifungal drugs. Voriconazole had the lowest geometric mean MIC (0.35 μg/ml), followed by posaconazole (0.37 μg/ml), amphotericin B (0.4 μg/ml), and isavuconazole (1.16 μg/ml). Caspofungin, anidulafungin, fluconazole, and itraconazole had no activity.

Phaeoacremonium: from esca disease to phaeohyphomycosis

Phaeoacremonium spp. are commonly isolated from stems and branches of diseased woody hosts, and humans with phaeohyphomycosis. The genus Phaeoacremonium (Togniniaceae, Togniniales) has recently been monographed, and presently contains 46 species, while its sexual morph, Togninia, contains 26 epithets, of which 13 are insufficiently known. In this review we summarise information pertaining to the global distribution, pathology, ecology, and detection of these species, and present a case for retaining the genus Phaeoacremonium over that of Togninia. Furthermore, to obtain a single nomenclature, the following new combinations are also proposed: Phaeoacremonium africanum, P. aquaticum, P. fraxinopennsylvanicum, P. griseo-olivaceum, P. inconspicuum, P. leptorrhynchum, P. minimum, and P. vibratile.

Dual Invasive Infection with Phaeoacremonium parasiticum and Paraconiothyrium cyclothyrioides in a Renal Transplant Recipient: Case Report and Comprehensive Review of the Literature of Phaeoacremonium Phaeohyphomycosis

Despite increasing reports of human infection, data about the optimal care of Phaeoacremonium infections are missing. We report a case of an infection due to Phaeoacremonium parasiticum and Paraconiothyrium cyclothyrioides, initially localized to skin and soft tissue, in a kidney transplant patient. Despite surgical drainage and excision of the lesion and combination antifungal therapy with voriconazole and liposomal amphotericin B, a disseminated infection involving the lungs and brain developed and led to death. We performed a systematic literature review to assess the general features and outcome of human infections due to Phaeoacremonium species. Thirty-six articles were selected, and 42 patients, including ours, were reviewed. Thirty-one patients (74%) were immunocompromised because of organ or bone marrow transplantation (n = 17), diabetes or glucose intolerance (n = 10), rheumatoid arthritis or Still's disease (n = 4), chronic hematological diseases (n = 3), or chronic granulomatous disease (n = 3). Ten patients (24%) reported initial cutaneous trauma. Skin and soft tissue infections represented 57% of infections (n = 24), and disseminated infections, all occurring in immunocompromised patients, represented 14% of infections (n = 6). The main antifungal drugs used were azoles (n = 41) and amphotericin B (n = 16). Surgical excision or drainage was performed in 64% of cases (n = 27). The cure rate was 67% (n = 28). There were 10% cases of treatment failure or partial response (n = 4), 19% relapses (n = 8), and 7% losses to follow-up (n = 3). The death rate was 19% (n = 8). Management of Phaeoacremonium infections is complex because of slow laboratory identification and limited clinical data, and treatment relies on a combination of surgery and systemic antifungal therapy.

Pulmonary phaeohyphomycosis caused by phaeoacremonium in a kidney transplant recipient: successful treatment with posaconazole

We report a rare case of pulmonary phaeohyphomycosis in a 49-year-old woman 6 years after kidney transplantation. She presented with dyspnea, cough, and fatigue. Her chest CT scan revealed nodular opacities in the right upper lung. A fine needle aspirate biopsy culture yielded Phaeoacremonium and surgical pathology of the biopsy showed chronic inflammation. We successfully treated her with posaconazole and managed drug interactions between posaconazole and tacrolimus. This is the second reported case of biopsy-proven pulmonary infection by Phaeoacremonium in a kidney transplant recipient and successfully treated with posaconazole.

Phaeohyphomycosis Caused by Phaeoacremonium rubrigenum in an Immunosuppressive Patient: A Case Report and Review of the Literature

Phaeohyphomycosis (PHM) is a rare, deep fungal infection of the skin and subcutaneous tissues caused by dematiaceous fungi. In this report, we describe a case of PHM caused by Phaeoacremonium rubrigenum, which is generally known to infect woody plants. We detected the gray-blackish villi by biopsy culture material, and slide culture revealed the conidia arising from slightly tapering phialides. Furthermore, we differentiated these fungi as P. rubrigenum by Basic Local Alignment Search Tool (BLAST) algorithm. We performed surgical debridement of disseminated nodules and administered oral itraconazole for a duration of 4 weeks. One year after stopping itraconazole, there was no sign of relapsing subcutaneous nodules. To our knowledge, this is the third case report of PHM developing from skin infection by P. rubrigenum in human.

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.

Phaeoacremonium parasiticum subcutaneous infection in a kidney-transplanted patient successfully treated by surgery

Human infection caused by Phaeoacremonium parasiticum is increasingly being reported. However, only a few case reports show its role as a soil-related contaminant of kidney recipients. We report here a case of a subcutaneous infection by P. parasiticum in a transplanted man. After 4 years, he reported a nonpainful nodule on his forefinger. It was surgically excised. Histological examination revealed dense fibrous connective tissue showing an extensive granulomatous reaction, including the presence of a wooden sliver, and hyaline, branched, and septate hyphae. Six months later, the patient relapsed and underwent large excision. Culture was positive for P. parasiticum. No antifungal drug was administered. Surgical excision was successful.

Mycotic cysts: report of 21 cases including eight pheomycotic cysts from Saudi Arabia

BACKGROUND

Mycotic cysts are subcutaneous cystic granulomas caused by either dematiaceous (pigmented) fungi (pheomycotic cysts) or eumycotic (nonpigmented fungi) present in soil, wood, and decaying plant material. These fungi gain access to the tissues via a wooden splinter or thorn. No deep tissue involvement or extension to bone is known to occur.

METHODS

We reviewed our surgical pathology files for the last 32 years. All cases with the diagnosis of cysts with fungi, thorns, or splinters and associated granulomatous and acute inflammation were reviewed. Gomori's silver and periodic acid-Schiff stains were performed in all cases.

RESULTS

Twenty-one cases of mycotic cyst were found, including eight pheomycotic cysts (one with a recurrent lesion seen 11 months after the initial excision of the cyst). Thirteen cysts had nonpigmented fungal hyphae. There were 14 males and seven females, with an age range of 5-76 years. The dorsum of the foot was the most frequently affected site (12 cases). Four cases involved the fingers, two involved the knee area, two involved the big toe, and one each involved the leg, ankle, and forearm. The cysts measured 0.6-4.5 cm in diameter. Histologically, there was granulomatous inflammation with a variable degree of neutrophilic infiltrate giving central abscess formation. Twelve cases showed a wooden splinter. All cases were positive for fungal organisms, mostly septate hyphae and spores that were highlighted by special stains. Fungal pigment, ranging from yellow-brown to light brown to black, was observed in eight cases. No extension to deep tissues was noted. The clinical impression varied widely including ganglion, sebaceous cyst, giant cell tumor of the tendon sheath, and lipoma. One patient was immunosuppressed following renal transplantation. All patients were treated by simple excision. No antifungal chemotherapy was needed or administered in any of the patients. One patient had a recurrence of his lesion within 1 year as a result of inadequate initial excision. A second re-excision was curative.

CONCLUSION

Mycotic cysts are uncommonly encountered lesions that can be easily missed, especially in cases with scant fungal elements, thus requiring special stains to detect the organisms. We reported 21 cases of mycotic cyst, including eight pheomycotic cysts, with emphasis on the histopathologic recognition of this unusual entity.

Subcutaneous phaeohyphomycosis caused byPhaeoacremonium parasiticumin a renal transplant patient

A 49-year-old renally transplanted man, under a five-year course of immunosuppressive therapy with prednisone and cyclosporine A, experienced a subcutaneous phaeohyphomycosis caused by Phaeoacremonium parasiticum. The clinical presentation consisted of impressive, large, inflammatory and draining cystic tumors on the left foot that had been present for one year. A significant improvement was obtained with itraconazole plus intralesional injection with amphotericin B. Drug interaction was observed between itraconazole and cyclosporine A causing a severe hypertensive crisis and requiring a temporary sharp reduction in cyclosporine administration. Subcutaneous phaeohyphomycosis caused by P. parasiticum is uncommon among major organ transplant patients but several cases have previously been published and some patterns are emerging, e.g., limbs are generally involved but no known traumatic event has preceded lesion development. The identification of the case isolate was confirmed using a recently published online system based in part on beta-tubulin sequence comparison.

Species of Phaeoacremonium associated with infections in humans and environmental reservoirs in infected woody plants

To date, three species of Phaeoacremonium have been associated with phaeohyphomycosis. These are P. parasiticum (formerly Phialophora parasitica), P. inflatipes, and P. rubrigenum. Numerous unknown isolates resembling Phaeoacremonium spp. have in recent years been isolated from human patients as well as from woody plants that appear to be the main environmental source of these fungi. Nine new Phaeoacremonium species, of which six were obtained as etiologic agents of human opportunistic infection, are reported. They can be identified based on their cultural and morphological characters, and the identifications are strongly supported in phylogenetic analyses of partial sequences of the actin, beta-tubulin, and calmodulin genes. A multiple-entry electronic key based on morphological, cultural, and beta-tubulin sequence data was developed to facilitate routine species identification. Reexamination of all isolates of P. inflatipes associated with human disease showed them to be misidentified and to belong to the new taxa described here.

Phaeoacremonium rubrigenum — Hyphomycete associated with bark beetles found in Czechia

Phaeoacremonium is a recently described genus (Crous et al. 1996) associated with decline diseases of woody hosts and with human infections. During a study of surface mycobiota of the oak bark beetles, the hyphomycetous microfungus Phaeoacremonium rubrigenum was isolated from larvae of Scolytus intricatus (Coleoptera: Scolytidae) and their galleries on Quercus robur and also from an adult of Leperisinus fraxini found under the bark of Fraxinus excelsior. The species determination was confirmed by rDNA (ITS1-5.8S-ITS2) comparison. P. rubrigenum was recorded for the first time in Czechia. The records on oak are considered to be the first ones in the world. A description of morphological features and figures of the fungus are given. Representative strains are maintained in the Culture Collection of Fungi (CCF), Faculty of Science, Charles University (Prague, Czechia).

Two cases of subcutaneous infection due to Phaeoacremonium spp

We describe two cases in Brazil of human subcutaneous infections due to Phaeoacremonium spp. The first case was caused by Phaeoacremonium aleophilum. The patient presented with a unique fistulized nodule on the left ankle. The fungus was detected by direct microscopic examination and was isolated repeatedly from material collected from the lesion. This is the first reported case of human infection caused by this fungus. The second case was caused by Phaeoacremonium rubrigenum. The patient presented with multiple nodules around the left ankle and foot. The fungus was detected by direct examination of pus and histological sections of the nodules. It was repeatedly isolated from the clinical specimens. This is the second reported case of human infection caused by this species.