Scopulariopsis/Microascus isolation in lung transplant recipients: A report of three cases and a review of the literature

Microascus cirrosus SZ 2021: A potentially new genotype of Microascus cirrosus, which can cause fatal pulmonary infection in patients with acute leukemia following haplo‑HSCT

Uncommon Microascus cirrosus (M. cirrosus) species have been reported to cause an increasing number of subcutaneous and invasive fungal infections worldwide; since the first human infection was reported in 1992, seven cases have been reported in PubMed. The present study reports a novel genotype named M. cirrosus SZ 2021 isolated from a patient undergoing hematopoietic stem cell transplantation, who exhibited extensive drug resistance and suffered a fatal pulmonary infection. This isolated M. cirrosus was cultured and determined by morphological observation, multi-locus sequence typing, matrix-assisted laser desorption and ionization time-of-flight mass spectrometry, and whole genome sequencing by next-generation sequencing. The whole nucleotide sequence (32.61 Mb) has been uploaded in the NCBI database (PRJNA835605). In addition, M. cirrosus SZ 2021 was not sensitive to the commonly used antifungal drugs, including fluconazole, amphotericin B, 5-flucytosine and caspofungin. The current literature on human infections by M. cirrosus was reviewed to closely define the comprehensive clinical characteristics and etiological identification. In brief, the present study identified a new M. cirrosus and summarized the clinical characteristics of fungal pneumonia by M. cirrosus species. Complete laboratory identification methods from morphology to gene sequencing were also established for an improved etiological identification and further investigation into the real prevalence of invasive pneumonia by M. cirrosus.

Pulmonary Microascus cirrosus infection in an immunocompetent patient with bronchiectasis: A case report

Microascus species are widely distributed and rarely cause invasive infection in humans. Here we report a case of lung Microascus cirrosus infection in an immunocompetent patient with bronchiectasis. While on systemic voriconazole and aerosolized amphotericin B for three months, the patient's overall condition improved. This case report highlights the possibility of rare pathogen infection occurred in a bronchiectasis patient, as well as the importance of accurate diagnosis and individualized therapy of pulmonary Microascus infection.

Nebulized Micafungin Treatment for Scopulariopsis/Microascus Tracheobronchitis in Lung Transplant Recipients

Scopulariopsis/Microascus isolates cause infections with high mortality in lung transplant recipients. Treatment is challenging due to antimicrobial resistance. We describe two cases of Scopulariopsis/Microascus tracheobronchitis in lung transplant recipients successfully treated with nebulized micafungin. This antifungal was well tolerated and achieved high concentrations in epithelial lining fluid up to 14 h after nebulization without significant plasma concentrations. Nebulized micafungin may be a safe and effective option for the treatment of fungal tracheobronchitis.

First reported case of disseminated Microascus gracilis infection in a lung transplant patient

Microascus gracilis is a specie of the genus Microascus in the family of Microascaceae and has been isolated from lung. It has never been reported as the cause of disseminated infection in humans. Herein, we report a fatal case of disseminated Microascus gracilis infection in a 65-year-old man with a history of primary idiopathic pulmonary fibrosis, status-post bilateral lung transplant. His course was complicated by donor lung cultures positive for multiple organisms and persistent pleural effusions. Multiple lung biopsy and bronchial lavage specimens were negative for mold. Later, pleural fluid cultures grew M. gracilis confirmed by DNA sequencing. Despite aggressive antifungal treatment, the patient continued to deteriorate with altered mental status. Imaging showed scattered hemorrhagic and hypodense lesions in the brain. The patient eventually succumbed to his infections and a restricted autopsy was performed. Autopsy findings included multiple hemorrhagic foci and abscesses involving the whole brain. Numerous punctuate, tan-white circular lesions were on the endocardium and diffuse tan exudates covered the pericardium and lungs. Histologically, similar fungal organisms with septate branching hyphae and short chains of conidia were identified, along with hemorrhage, neutrophilic inflammation, and necrosis in the brain, pleura, peripheral parenchyma of lungs and heart. This is the first reported case of disseminated M. gracilis infection in an immunosuppressed human, indicating it can cause localized infections and disseminated infections. This case increases our awareness of such fatal opportunistic infections, particularly in lung transplant patients, and urges earlier aggressive prophylaxis, diagnosis, and treatment.

China lung transplantation developing: past, present and future

Lung transplantation in China has been developing for almost 40 years (1979-2019). The pioneers of this procedure experienced struggles and obstacles upon accomplishment of the initial 20 cases of lung transplantation. Like the expanding process of transplant programs elsewhere in western countries and other regions in Asia, transplant teams in China have found their own way to step forward, with the establishment of the two largest centers in Beijing and Wuxi. Since 2015, which was a novel start and milestone for transplant affairs in China, the pace of transplant volume and comparable quality of care for lung transplant recipients have increased noticeably. We reviewed the advancement of lung transplantation programs and registry setup in China and indicated that more socioeconomic factors and human care aspects needed to be considered to benefit Chinese recipients, which may further inspire the modification of criteria of listing and organ utilization based on East Asian cultural and traditional origins.

Lung transplantation in China between 2015 and 2018

BACKGROUND

Lung transplantation (LT) has been demonstrated as the only effective therapy for patients with end-stage lung diseases. Increasing listed lung transplant candidates and expanding volumes of lung transplant centers across China require well-organized programs and registry data collection based on the large population. This study aimed to summarize and analyze the data of LT development in China.

METHODS

We retrospectively collected and analyzed data from the China Lung Transplantation Registry (CLuTR). Key data were reported from the registry with transplant types, indications, donor and recipient characteristics, outcomes and survival. The survival <30 days, 1-year and 3-year survival rates were estimated with risk factors identified.

RESULTS

CLuTR contained data from 1053 lung transplants performed through January 1st, 2015 to December 31st, 2018 reported by 18 registered transplant centers. The largest category of diagnosis before transplantation was idiopathic interstitial pneumonitis. The total <30 days, 1-year and 3-year survival rates in CLuTR were 81.45%, 70.11%, and 61.16% with discrepancy by indications. Large proportion of recipients who were more than 60 years old required higher standard of care. Infection-related complications resulted in more death events in the early post-surgery periods. New York Heart Association grading at listing, extra-corporeal membrane oxygenation usage peri-transplantation, allograft dysfunction (primary graft dysfunction >Grade 0), renal insufficiency (estimated glomerular filtration rate <60 mL·min·1.73 m), were independently associated with a higher risk for 3-year mortality in the entire cohort.

CONCLUSIONS

Facing more end-stage of lung diseases and comorbidities, this study analyzed the outcomes and survival of LT recipients in China. Further prospectively stratified analyses with longer follow-up will be needed.