Phaeoacremonium parasiticum invasive infections and airway colonization characterized by agar block smear and ITS and β-tubulin gene sequencing

Phaeohyphomycosis in China

Background

Due to more attentions paid to melanized fungi over the past few decades and under the background of the global coronavirus disease 2019 pandemic (COVID-19) the fact that the virus itself and the immunosuppressive agents such as glucocorticoids can further increase the risk of infections of deep mycoses, the number of patients with phaeohyphomycosis (PHM) has a substantial increase. Their spectrum is broad and the early diagnosis and treatments are extremely sticky. This study aims to more comprehensively understand the clinical features of phaeohyphomycosis in China over 35 years and to establish a more applicable systematical classification and severity grades of lesions to guide treatments and prognosis.

Methods

We reviewed 174 cases of proven phaeohyphomycosis reported in Chinese and English language literature from 1987 to 2021 and we also made the accurate classification definitions and detailed information about the epidemiology, species of clinical dematiaceous fungi, minimum inhibitory concentration values, clinical features, treatments, and prognosis.

Results

The mortality of cerebral, disseminated and pulmonary phaeohyphomycosis are 55%, 36%, and 25%. Nearly 19% of patients had poor quality of life caused by the complications such as disability, disfigurements, and blindness. The overall misdiagnosis rate of phaeohyphomycosis was 74%. Moderate to severe rashes are accounting for 82% of subcutaneous phaeohyphomycosis. The areas of the head and face are mostly affected accounting for 16% of severe rashes. Nearly 30% of invasive infections of phaeohyphomycosis are triggered by recurrent lesions. Voriconazole, itraconazole, amphotericin B deoxycholate (AmB-DOC), and terbinafine were most commonly used but diagnosis and treatments of phaeohyphomycosis remain challenging in reality.

Conclusions

Our classifications are likely to be more practical and easier to popularize, and there are still also plenty of characteristics in these non-specific lesions. There’re no significant variations in cure rates, or death rates between three grades of lesions. But patients with severe rashes have longer courses and lower effective rates.

The type isolate of a rare Phaeoacremonium species as a cause of human eumycetoma

An isolate of unknown identity that had been identified as causing eumycetoma was retained in an international culture collection, and eventually became the nomenclatural type isolate of the rarely encountered Phaeoacremonium sphinctrophorum. The case featured an indurated, painless, swollen lesion on the dorsum of the foot that had developed in a Canadian resident who had previously been a farmer in Laos. Resection alone was curative.

Candida Tropicalis renal microabscesses in a child with leukemia confirmed using nucleic acid amplification and recovery after prolonged antifungal and corticosteroid treatment

We report the first case of microabscesses detected by polymerase chain reaction (PCR) amplification of nucleic acid from ultrasound-guided aspirated fluid in a three-year old boy with acute lymphoblastic leukemia and febrile neutropenia during induction chemotherapy. Fever persisted despite effective antifungal treatment. The addition of corticosteroid therapy successfully controlled the suspected immune reconstitution inflammatory syndrome (IRIS). This case highlights the utility of PCR and adjunctive corticosteroid in the approach of Candida tropicalis renal microabscesses in leukemic patients undergoing chemotherapy.

Phaeoacremonium Tenosynovitis of the Wrist

A 79-year-old man presented with a painless, soft, subcutaneous mass lesion of the right volar wrist that had been slowly growing for 3 years. A cloudy, yellow serous effusion was aspirated from the punctured mass, from which Phaeoacremonium spp., an extremely rare cause of tenosynovitis, was isolated in culture. Total synovectomy was performed without the use of antifungal agents. No recurrence or complications occurred as of 6 months after surgery. Fungal infection is rare but should be considered in the differentiation of chronic tenosynovitis.

Dielectrophoresis for Biomedical Sciences Applications: A Review

Dielectrophoresis (DEP) is a label-free, accurate, fast, low-cost diagnostic technique that uses the principles of polarization and the motion of bioparticles in applied electric fields. This technique has been proven to be beneficial in various fields, including environmental research, polymer research, biosensors, microfluidics, medicine and diagnostics. Biomedical science research is one of the major research areas that could potentially benefit from DEP technology for diverse applications. Nevertheless, many medical science research investigations have yet to benefit from the possibilities offered by DEP. This paper critically reviews the fundamentals, recent progress, current challenges, future directions and potential applications of research investigations in the medical sciences utilizing DEP technique. This review will also act as a guide and reference for medical researchers and scientists to explore and utilize the DEP technique in their research fields.

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.

Clinical Characteristics, Laboratory Identification, and In Vitro Antifungal Susceptibility of Yarrowia (Candida) lipolytica Isolates Causing Fungemia: a Multicenter, Prospective Surveillance Study

Our case series showed that uncomplicated Yarrowia lipolytica fungemia might be treated with catheter removal alone. The Vitek 2 YST identification (ID) card system, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), and internal transcribed spacer and 25S nuclear ribosomal DNA (nrDNA) gene sequencing provided reliable identification. All isolates had low MICs to voriconazole, echinocandins, and amphotericin B.

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.

Metabolomics Analysis Reveals Specific Novel Tetrapeptide and Potential Anti-Inflammatory Metabolites in Pathogenic Aspergillus species

Infections related to Aspergillus species have emerged to become an important focus in infectious diseases, as a result of the increasing use of immunosuppressive agents and high fatality associated with invasive aspergillosis. However, laboratory diagnosis of Aspergillus infections remains difficult. In this study, by comparing the metabolomic profiles of the culture supernatants of 30 strains of six pathogenic Aspergillus species (A. fumigatus, A. flavus, A. niger, A. terreus, A. nomius and A. tamarii) and 31 strains of 10 non-Aspergillus fungi, eight compounds present in all strains of the six Aspergillus species but not in any strain of the non-Aspergillus fungi were observed. One of the eight compounds, Leu–Glu–Leu–Glu, is a novel tetrapeptide and represents the first linear tetrapeptide observed in Aspergillus species, which we propose to be named aspergitide. Two other closely related Aspergillus-specific compounds, hydroxy-(sulfooxy)benzoic acid and (sulfooxy)benzoic acid, may possess anti-inflammatory properties, as 2-(sulfooxy)benzoic acid possesses a structure similar to those of aspirin [2-(acetoxy)benzoic acid] and salicylic acid (2-hydroxybenzoic acid). Further studies to examine the potentials of these Aspergillus-specific compounds for laboratory diagnosis of aspergillosis are warranted and further experiments will reveal whether Leu–Glu–Leu–Glu, hydroxy-(sulfooxy)benzoic acid and (sulfooxy)benzoic acid are virulent factors of the pathogenic Aspergillus species.

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.

Subcutaneous phaeohyphomycosis in a patient with IgG4-related sclerosing disease caused by a novel ascomycete, Hongkongmyces pedis gen. et sp. nov.: first report of human infection associated with the family Lindgomycetaceae

No members of the freshwater ascomycetes family Lindgomycetaceae have been associated with human infections. We isolated a mould (HKU35(T)) from the biopsy specimen of a patient with invasive foot infection and underlying immunoglobulin G4-related sclerosing disease. Histology showed florid, suppurative, granulomatous inflammation in the dermis, with central microabscess formation surrounded by epithelioid histiocytes, scattered giant cells, and a small number of lymphocytes. A Grocott stain revealed fungal elements in the center of the lesion. On Sabouraud glucose agar, HKU35(T) grew as gray and velvety colonies. Among the members of the family Lindgomycetaceae, HKU35(T) was the only strain that grew at 37°C. Microscopically, only sterile mycelia, but no fruiting bodies, were observed. HKU35(T) was susceptible to itrazonazole, voriconazole, and posaconazole, which was in line with the patient's clinical response to itraconazole treatment. Internal transcribed spacer and partial 18S nuclear rDNA (nrDNA), 28S nrDNA, β-tubulin gene, and EF1α gene sequencing showed that HKU35(T) occupied a unique phylogenetic position, most closely related to but distinct from members of the genera Clohesyomyces and Lindgomyces. We propose a new genus and species, Hongkongmyces pedis gen. et sp. nov., to describe this fungus, which belongs to the family Lindgomycetaceae in the orderPleosporales of class Dothideomycetes. This case also represents the first report of human infection associated with the family Lindgomycetaceae.

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.

Misidentification of Aspergillus nomius and Aspergillus tamarii as Aspergillus flavus: characterization by internal transcribed spacer, β-Tubulin, and calmodulin gene sequencing, metabolic fingerprinting, and matrix-assisted laser desorption ionization-time of flight mass spectrometry

Aspergillus nomius and Aspergillus tamarii are Aspergillus species that phenotypically resemble Aspergillus flavus. In the last decade, a number of case reports have identified A. nomius and A. tamarii as causes of human infections. In this study, using an internal transcribed spacer, β-tubulin, and calmodulin gene sequencing, only 8 of 11 clinical isolates reported as A. flavus in our clinical microbiology laboratory by phenotypic methods were identified as A. flavus. The other three isolates were A. nomius (n = 2) or A. tamarii (n = 1). The results corresponded with those of metabolic fingerprinting, in which the A. flavus, A. nomius, and A. tamarii strains were separated into three clusters based on ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC MS) analysis. The first two patients with A. nomius infections had invasive aspergillosis and chronic cavitary and fibrosing pulmonary and pleural aspergillosis, respectively, whereas the third patient had A. tamarii colonization of the airway. Identification of the 11 clinical isolates and three reference strains by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) showed that only six of the nine strains of A. flavus were identified correctly. None of the strains of A. nomius and A. tamarii was correctly identified. β-Tubulin or the calmodulin gene should be the gene target of choice for identifying A. flavus, A. nomius, and A. tamarii. To improve the usefulness of MALDI-TOF MS, the number of strains for each species in MALDI-TOF MS databases should be expanded to cover intraspecies variability.

Fatal empyema thoracis caused by Schizophyllum commune with cross-reactive cryptococcal antigenemia

We report a fatal case of Schizophyllum commune empyema thoracis with cross-reactive cryptococcal antigenemia. In vitro testing confirmed the ability of the fungus to cause a positive cryptococcal antigen latex agglutination system (CALAS) test result. Such a result may lead to delay in diagnosis and treatment, as most strains of S. commune are resistant to fluconazole.

Sporopachydermia cereana fungaemia in refractory leukaemia presenting as breakthrough infection during micafungin therapy

The Sporopachydermia cereana species lives in decaying stems of cactus and is exceptionally rare as a human pathogen. A 57-year-old man with therapy-refractory acute promyelocytic leukaemia developed severe neutropaenia. After about 3 weeks of micafungin used as prophylaxis, he developed high fever, multiple pulmonary nodular infiltrates and a painful leg lesion. Blood culture yielded a yeast which was not identified by the Vitek 2 system. On ITS1-5.8S-ITS2 gene sequencing, the isolate was identified as S. cereana. Antifungal sensitivity by the Etest showed that the minimum inhibitory concentration for fluconazole was 0.75 μg/mL, and for anidulafungin, it was >32 μg/mL. He responded to liposomal amphotericin B but later died of Escherichia coli septicaemia. There were no cactus plants in the vicinity, suggesting that S. cereana might have alternative habitats.

Clinical spectrum of exophiala infections and a novel Exophiala species, Exophiala hongkongensis

We characterized 12 Exophiala strains isolated from patients over a 15-year period to the species level using phenotypic tests and internal transcribed spacer (ITS) and Rpb1 sequencing and described the clinical spectrum of the 12 patients. Eight patients had nail or skin infections, two had invasive infections, and two had colonization of the gastrointestinal tract. ITS and Rpb1 sequencing showed that 11 of the 12 strains were known Exophiala species (E. oligosperma [n = 3], E. jeanselmei [n = 2], E. lecanii-corni [n = 2], E. bergeri [n = 1], E. cancerae [n = 1], E. dermatitidis [n = 1], and E. xenobiotica [n = 1]), which included the first reported cases of onychomycosis caused by E. bergeri and E. oligosperma. The 12th strain (HKU32(T)), isolated from the nail clipping of the right big toe of a 68-year-old female patient with onychomycosis, possessed unique morphological characteristics distinct from other Exophiala species. It grew very slowly and had a velvety colony texture after 28 days, short conidiophores of the same olivaceous color as the supporting hyphae, numerous spores, and no chlamydospore-like cells. ITS, Rpb1, β-tubulin, and β-actin gene sequencing unambiguously showed that HKU32(T) was clustered with but formed branches distinct from other Exophiala species in phylogenetic trees. We propose the new species Exophiala hongkongensis to describe this novel fungus.