Schizophyllum commune: an unusual of agent bronchopneumonia in an immunocompromised patient

Pneumonia due to Schizophyllum commune in a Patient with Acute Myeloid Leukemia: Case Report and Literature Review

Schizophyllum commune is a mold in phylum Basidiomycota and is an uncommon human pathogen. Sinusitis and allergic bronchopulmonary mycosis are the two major diseases caused by S. commune. Although there have been several reports of invasive fungal diseases, most of them were invasive sinusitis. We present a case of invasive fungal pneumonia due to S. commune, developed in a patient with acute myeloid leukemia presenting neutropenic fever. The diagnosis was made by characteristic macroscopic and microscopic findings of fungal isolate and was confirmed via sequencing of internal transcribed spacer region. The patient was improved after 8 weeks of antifungal therapy based on the susceptibility result. We propose that S. commune should be considered as an emerging pathogen of invasive fungal pneumonia when a patient is under immunocompromised state. We also reviewed global literatures focused on the invasive fungal diseases caused by S. commune.

A Schizophyllum commune fungus ball in a lung cancer cavity: a case report

Background

Schizophyllum commune is a basidiomycete that lives in the environment and can cause infections, mainly those of the respiratory system. Although S. commune is increasingly reported as a cause of allergic bronchopulmonary mycosis and sinusitis, cases of fungal ball formation are extremely uncommon. Identification of S. commune is difficult using routine mycological diagnostic methods, and in clinically suspicious cases, internal transcribed spacer sequencing should be used for diagnosis. Here, we report a first case of lung cancer with a fungal ball formation of S. commune, confirmed by analyzing the internal transcribed spacer.

Case presentation

A 76-year-old man with diabetes and hypertension was admitted to the hospital with a chief complaint of hemosputum, which he had for about 19 months. A computed tomography image of the patient’s chest showed a cavity and internal nodule in the left upper lobe of his lung. A left upper lobectomy was performed, and histopathological examination revealed squamous cell carcinoma of the lung and a fungal ball. The isolate from the surgical specimen was identified as S. commune by analyzing the internal transcribed spacer. The patient had no recurrence of the infection during 5 months of follow-up.

Conclusions

Only three cases of lung fungal balls caused by S. commune have been previously reported, and this is the first case of lung cancer cavity with a fungal ball formation. In cases of fungal ball formation in the lung, S. commune should be considered a possible causative microorganism.

Recent developments in less known and multi-resistant fungal opportunists

Fungal infections have increased in recent years due to host factors, such as oncohaematological and transplant-related disorders, immunosuppressive therapy, and AIDS. Additionally, molecular and proteomic facilities have become available to identify previously unrecognizable opportunists. For these reasons, reports on less-known and recalcitrant mycoses, such as those caused by black fungi, hyaline filamentous fungi, coelomycetes, Mucorales, and non-Candida yeasts have emerged. In this review, novel taxonomy in these groups, which often are multi-resistant to one or several classes of antifungals, is discussed. Clinical presentations, diagnosis and current treatment of some major groups are summarised.

A case of primary pulmonary Schizophyllum commune empyema treated with video-assisted thoracoscopic decortication

Schizophyllum commune (S. commune) is an environmental basidiomycete bracket fungus that can rarely cause invasive fungal disease. Its diagnosis is challenging and often missed. We present a rare case of a 56-year-old diabetic gentleman with a 6-months history of progressive productive cough, small volume hemoptysis and non-resolving fungal empyema treated with video-assisted thoracoscopic decortication. Pulmonary infection of S. Commune is extremely rare and can manifest as complex fungal empyema. Close cooperation between respirologists, thoracic surgeons and microbiologists is critical in the diagnosis and treatment of such cases.

Human infections due to Schizophyllumcommune: Case report and review of the literature

Schizophyllumcommune is an environmental basidiomycetous fungus, causing occasional, predominantly respiratory, infections in humans. Although S. commune is considered an emerging pathogen, some authors pointed out the possibility that the increase in the diagnosed cases may be also due to recent advances in diagnostic technologies now allowing a more prompt and precise identification at the species level. Here we describe the first Italian case of chronic non-invasive fungal rhinosinusitis due to S. commune in an immunocompetent subject and update the literature review on S. commune sinusitis published between 2012-2019. A timely diagnosis is important to avoid local and systemic complications due to infection with this fungus. In our case, prompt identification at species level was only possible with the use of MALDI-TOF mass spectrometry and confirmed by sequence analysis of ribosomal DNA ITS regions, due to the difficulty in achieving a correct and rapid identification using routine morphological analysis.

Resolving the pathogenicity factors of a novel opportunistic fungus Schizophyllum commune at molecular level

Schizophyllum commune is a well-known mushroom forming fungi which is an edible one due to its nutritive value. It exhibits a special wood degrading mechanism to grow in decay matters by releasing a series of enzymes. These enzymes might make them an opportunistic pathogen which has been reported to infect various animals and human beings too. Although these fungi were identified as human and animal pathogens, their mechanisms of pathogenesis and the key virulence factors involved in disease establishment are not known. In this study, we reported this fungal infection in freshwater fish for the first time and its morphological features. Further, we employed RNA-seq technique to identify the major virulence factors involved in the pathogenesis in fish and the network of interaction between the identified virulence factors were analysed. Also, we confirmed the virulence roles of this fungus during infection by qRT-PCR analysis. This study emphasizes the virulence nature of the common mushroom forming food fungus and the involvement of enzymes such as phosphoinositide phospholipase C, hexosaminidase and few toxins such as pesticidal and insecticidal crystal proteins which opened a new avenue in the virulence nature of edible mushrooms.

A case of otitis externa caused by Schizophyllum commune: An approach to antimicrobial stewardship using Gram staining of otorrhea in a medical clinic

Recently, basidiomycete Schizophyllum commune has been reported as a cause of allergic bronchopulmonary mycosis. However, it is rare as a cause of otitis externa. We experienced a very rare case of otitis externa caused by S. commune in a 68-year-old man with a history of chronic otitis media. We performed Gram staining at the first consultation and follow-up treatment and found fungal cells on the smear and treated him with an appropriate antifungal drug. The results of identification and antifungal susceptibility testing obtained in cooperation with clinical microbiologists at other facilities was very important for future treatment planning decisions. Medical practitioners worldwide should introduce a Gram staining tool into their workflow and cooperate closely with clinical microbiologists to achieve antimicrobial stewardship.

First report on cutaneous infectious granuloma caused by Schizophyllum commune

Background

Schizophyllum commune, a basidiomycetous fungus, is a common invader of rotten wood. This fungus rarely causes mycotic disease in humans, especially cutaneous infection. In this paper, we describe the first case of cutaneous granuloma caused by S. commune in a Chinese woman.

Case presentation

A 25-year-old female with a two-year history of erythema, papules, nodules, and scales on her sole of left foot was presented to our outpatient center. Samples were obtained by the scraping of lesion and for light microscopy. Hyphae were observed by microscopic examination. We carried out a skin tissue biopsy, which showed multiple granulomatous nodules. Biopsy specimens were also inoculated onto media. After being cultured on SDA at 27 °C for 7 days, spreading-woolly-white colonies grew on the inoculation sites of media containing chloramphenicol only and there^,s no other colonies grew. S. commune was identified by morphology methods, biochemical tests, and PCR sequencing. Pathological findings also aided in diagnosing cutaneous fungal granuloma. Oral itraconazole was applied. After 1 month of therapy, rashes on her left foot and pain were improved.

Conclusion

We describe the first case of cutaneous granuloma caused by Schizophyllum commune, which illustrates the importance of recognizing uncommon pathogenic fungal infections.

Uses and importance of wild fungi: traditional knowledge from the Tshopo province in the Democratic Republic of the Congo

BACKGROUND

Wild mushrooms constitute an important non-timber forest product that provides diverse substances and services, especially food and income for local communities from many parts of the world. This study presents original ethnomycological documentation from the dense rainforests of the Democratic Republic of the Congo.

METHODS

Ethnomycological surveys were made within local communities near the biosphere reserve of Yangambi and the Yoko forest reserve. The interviews involved 160 informants from six different ethnic communities (Bakumu, Turumbu, Topoke, Lokele, Ngelema, and Ngando). Specific reported use (RU), the relative importance (RI), and the cultural significance (CS) of wild edible fungi were calculated using quantitative data from enquiries.

RESULTS

The people from Tshopo use 73 species of wild mushrooms either for food (68 species), as medicine (9 species), in a recreational context (2 species), or related to myths and beliefs (7 species). Women are more involved in harvesting and are the main holders of cultural aspects related to fungi. The results show that knowledge of useful mushrooms differs between ethnic groups. The Ngando people have the highest ethnomycological expertise, which is expressed in their extensive cultural and practical use of fungi. Pleurotus tuber-regium is the most important species (MCSI = 1.9 and p value < 2.2e^-16) as it is being used for food, as a medicine, and more. Daldinia eschscholtzii is the most important (MUI = 0.86 and p value < 2.2e^-16) for medicinal applications, while Schizophyllum commune, Auricularia cornea, A. delicata, Marasmius buzungolo, and Lentinus squarrosulus are mostly appreciated for food. The latter five species are all wood-decaying saprotrophs.

CONCLUSION

Despite the presence of edible ectomycorrhizal taxa in the dense rainforests of Tshopo, local people only seem to have an interest in saprotrophic taxa. Some mushroom pickers deliberately cut down host trees to promote the development of saprotrophic taxa. Inducing forest degradation is considered beneficial as it promotes the development of saprotrophic taxa. The domestication of locally appreciated saprotrophic lignicolous fungi is proposed as a mitigating measure against fellings.

Epidural abscess caused by Schizophyllum commune: A rare case of rhinogenic cranial complication by a filamentous basidiomycete

Central nervous system (CNS) infections due to filamentous basidiomycetes are extremely rare. We encountered a case of epidural abscess due to Schizophyllum commune that extended from sinusitis. A 53-year-old Japanese man presented at our hospital with a headache. Computed tomography (CT) of the cranium and sinuses showed ethmoid and sphenoid sinusitis with no intracranial abnormalities. The patient was diagnosed with acute sinusitis and underwent antibiotic treatment. However, the symptoms deteriorated, and the patient came to our hospital again with consciousness disturbance. CT scan of the cranium and sinuses showed no improvement of sinusitis after antibiotic therapy and an epidural abscess emerged in the middle cranial fossa. Therefore, emergency craniotomy and endoscopic sinus fenestration were performed. Filamentous fungal elements were observed in both rhinorrhoea and epidural abscess. The symptoms improved after the operation and administration of liposomal amphotericin B. The clinical isolate was identified as S. commune by a molecular-based method. To our knowledge, this is the first report of epidural abscess due to this fungus. Although rare, clinicians should be aware that S. commune could be a causative agent of CNS infections.

First isolation of Schizophyllum commune in a harbor seal (Phoca vitulina)

To date, Schizophyllum commune infection has been identified in only humans and dogs. A 7-year-old female harbor seal (Phoca vitulina) died after exhibiting corneal opacity, anorexia, and labored respiration. At necropsy, phthisis of the left eyeball was detected, and multiple nodular lesions were observed in the thoracic and abdominal regions, especially in the lung, heart, and lymph nodes. Histopathologically, numerous hyphae were seen in granulomatous lesions in the eyes, lung, heart, and lymph nodules. An isolate on potato dextrose agar from the eyes, lung, and sputum yielded a rapidly growing white woolly mycelia with basidiocarps (fruiting bodies) at 37°C. A suitable temperature for mycelial growth was obtained at 25°C, although sustained growth also occurred at 37°C. The fungal isolate, KH-JPN15-011, had distinctive features including hyphae bearing spicules and clamp connections, which were consistent with the characteristics of basidiomycete fungus. The sequence of the internal transcribed spacer region of nuclear ribosomal DNA showed 99.67% (617 bp) similarity with those of S. commune Phylogenetic analysis showed that the present isolate is most closely related to the samples from the Old World. This is the first report of a fatal disease caused by S. commune in exotic animals. Previously reported human and canine infections have not included granulomatous endophthalmitis and myocarditis. After considering these and previous findings, there is a possibility that S. commune from the Old World may include numerous highly pathogenic strains.

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.

Filamentous Basidiomycetes in the Clinical Laboratory

Filamentous basidiomycetes are difficult to identify in the clinical laboratory, mostly due to lack of sporulation, and their role as agents of fungal infection can be difficult to assess. More cases of infection with these agents are being reported as more laboratories gain proficiency with the recognition of their subtle morphologic features and the use of DNA-based methods for identification. Most infections occur in the respiratory tract and sinuses, although brain infection has been reported. Susceptibility testing suggests that these agents will respond well to azole drugs other than fluconazole.

Molecular characterization and in vitro antifungal susceptibility profile of Schizophyllum commune, an emerging basidiomycete in bronchopulmonary mycoses

Schizophyllum commune (n = 30) showed lowest geometric mean MICs of isavuconazole (0.19 μg/ml), itraconazole (0.2 μg/ml), voriconazole (0.24 μg/ml), and amphotericin B (0.29 μg/ml) and high geometric mean MICs of fluconazole (19.39 μg/ml) and flucytosine (17.28 μg/ml). Five cases (of 8) of allergic bronchopulmonary mycosis that were treated with itraconazole had no recrudescence after 6 to 24 months of follow-up. One case each of invasive pulmonary mycosis and fungal ball were treated successfully with voriconazole and itraconazole.

Schizophyllum commune as an emerging fungal pathogen: a review and report of two cases

We report Schizophyllum commune as the aetiological agent of one case each of allergic broncho-pulmonary mycosis (ABPM) and pulmonary fungal ball, and present a literature review. The fungus was characterised by clamp connections, hyphal spicules, and formation of basidiocarps with basidiospores. The phenotypic identification was confirmed by sequencing of the ITS region. To-date, ABPM and pulmonary fungal ball to S. commune have been reported exclusively from Japan and North America respectively. Of the 71 globally reported cases due to S. commune, 45 (63%) were bronchopulmonary, 22 (31%) sinusitis and 4 extrapulmonary. Taken together, cases of bronchopulmonary disease and sinusitis numbered 67 (94%), indicating the respiratory tract as the primary target of disease. Concerning the country-wise distribution, Japan topped the list with 33 cases (46%), followed by Iran - 7 cases (10%), U.S.A. - 6 cases (9%), and a lower prevalence of 1.4-6% for the remaining 12 countries. The preponderance of the disease in Japan may be attributed to its greater awareness vis-à-vis that in other countries rather than to any geographical/climatic factors. We believe that the burden of S. commune-incited disease is currently underestimated, warranting comprehensive prospective studies to determine its prevalence.