Coinfection of disseminated Talaromyces marneffei and Mycobacteria kansasii in a patient with papillary thyroid cancer: A case report

Endolithic Fungal Diversity in Antarctic Oligocene Rock Samples Explored Using DNA Metabarcoding

In this study, we evaluated the fungal diversity present associated with cores of Oligocene rocks using a DNA metabarcoding approach. We detected 940,969 DNA reads grouped into 198 amplicon sequence variants (ASVs) representing the phyla Ascomycota, Basidiomycota, Mortierellomycota, Chytridiomycota, Mucoromycota, Rozellomycota, Blastocladiomycota, Monoblepharomycota, Zoopagomycota, Aphelidiomycota (Fungi) and the fungal-like Oomycota (Stramenopila), in rank abundance order. Pseudogymnoascus pannorum, Penicillium sp., Aspergillus sp., Cladosporium sp., Aspergillaceae sp. and Diaporthaceae sp. were assessed to be dominant taxa, with 22 fungal ASVs displaying intermediate abundance and 170 being minor components of the assigned fungal diversity. The data obtained displayed high diversity indices, while rarefaction indicated that the majority of the diversity was detected. However, the diversity indices varied between the cores analysed. The endolithic fungal community detected using a metabarcoding approach in the Oligocene rock samples examined contains a rich and complex mycobiome comprising taxa with different lifestyles, comparable with the diversity reported in recent studies of a range of Antarctic habitats. Due to the high fungal diversity detected, our results suggest the necessity of further research to develop strategies to isolate these fungi in culture for evolutionary, physiological, and biogeochemical studies, and to assess their potential role in biotechnological applications.

HIV-Negative Case of Talaromyces marneffei Pulmonary Infection with Liver Cirrhosis in China: A Case Report and Literature Review

Background

Talaromyces marneffei (TM) is the third most prevalent opportunistic infection in HIV-positive patients after tuberculosis and cryptococcosis. However, such infection of non-HIV individuals has rarely been reported.

Case Presentation

We describe a very rare case of a 52-year-old male who presented with a single space-occupying lesion on the right lung and was eventually diagnosed with pulmonary TM infection. The patient was HIV-negative and had liver cirrhosis with portal vein thrombosis. Lung tissue next-generation sequencing (NGS) revealed TM infection. We successfully treated the patient with voriconazole for 8 weeks and observed lesion absorption via subsequent CT. The patient consumed wild bamboo rats two months before admission. Mutations related to congenital immune deficiency were not detected by whole-exome sequencing.

Conclusion

Early and timely diagnosis is critical for improving patient prognosis. NGS plays a vital role in the diagnosis of pulmonary TM infection in patients. To our knowledge, this is the first published case of pulmonary TM infection in an HIV-negative patient with liver cirrhosis.

Potential use of multikinase inhibitors in immunosuppressed patients with malignancies including thyroid cancer

In this article, we focus on a variety of immunosuppression scenarios and whether multikinase inhibitors, as systemic therapy for advanced thyroid carcinoma (TC), could be useful for the treatment of immunocompromised patients with TC. Lenvatinib and sorafenib, among other MKIs, have become the standard of care for advanced TC based on their efficacy data and despite their adverse effects. Currently, published data on MKIs in immunosuppressed patients are scarce. Secondary malignancies can arise in immunosuppressed patients who have undergone solid organ transplantation, human immunodeficiency virus-infected patients, and hematopoietic stem cell transplant recipients. This review will explore different immunosuppression settings, the risk of secondary malignancies in immunosuppressed patients, and the special characteristics of this population. Some considerations regarding anticancer treatment in immunosuppressed patients with advanced malignancies are reviewed.

Pulmonary Talaromycosis: A Window into the Immunopathogenesis of an Endemic Mycosis

Talaromycosis is an invasive mycosis caused by the thermally dimorphic saprophytic fungus Talaromyces marneffei (Tm) endemic in Asia. Like other endemic mycoses, talaromycosis occurs predominantly in immunocompromised and, to a lesser extent, immunocompetent hosts. The lungs are the primary portal of entry, and pulmonary manifestations provide a window into the immunopathogenesis of talaromycosis. Failure of alveolar macrophages to destroy Tm results in reticuloendothelial system dissemination and multi-organ disease. Primary or secondary immune defects that reduce CD4+ T cells, INF-γ, IL-12, and IL-17 functions, such as HIV infection, anti-interferon-γ autoantibodies, STAT-1 and STAT-3 mutations, and CD40 ligand deficiency, highlight the central roles of Th1 and Th17 effector cells in the control of Tm infection. Both upper and lower respiratory infections can manifest as localised or disseminated disease. Upper respiratory disease appears unique to talaromycosis, presenting with oropharyngeal lesions and obstructive tracheobronchial masses. Lower respiratory disease is protean, including alveolar consolidation, solitary or multiple nodules, mediastinal lymphadenopathy, cavitary disease, and pleural effusion. Structural lung disease such as chronic obstructive pulmonary disease is an emerging risk factor in immunocompetent hosts. Mortality, up to 55%, is driven by delayed or missed diagnosis. Rapid, non-culture-based diagnostics including antigen and PCR assays are shown to be superior to blood culture for diagnosis, but still require rigorous clinical validation and commercialisation. Our current understanding of acute pulmonary infections is limited by the lack of an antibody test. Such a tool is expected to unveil a larger disease burden and wider clinical spectrum of talaromycosis.

Disseminated Coinfection by Mycobacterium fortuitum and Talaromyces marneffei in a Non-HIV Case

Background

Mycobacterium fortuitum is a rapidly growing non-tuberculous mycobacterium (NTM) with weak pathogenicity. Here, we present a rare case of disseminated M. fortuitum and Talaromyces marneffei coinfection in a human immunodeficiency virus (HIV) negative patient.

Case Presentation

A 28-year-old female was admitted to our hospital due to 2 months of swelling of lymph nodes on the right side of her cervix, accompanied by repeated low fever for more than 1 month. Biopsy of the right cervical lymph node and endobronchial ultrasound-guided transbronchial fine needle aspiration (EBUS-TBNA) both suggested granulomatous inflammation. The bacterial culture and mycobacteria examination of the lesion as well as HIV antibody test were all negative. Disseminated T. marneffei infection was diagnosed by the quantitative polymerase chain reaction (qPCR) results from the blood showing 1798 copies/ul. In the meantime, treatment with amphotericin B combined with cefoxitin was administered for suspected NTM infection. However, the once-dropped fever recurred and the lymph nodes continued to swell. Metagenomics next-generation sequencing (mNGS) detection of the lymph nodes indicated M. fortuitum. After combination treatment with amphotericin B, voriconazole, linazolamide, and imipenem, the patient's body temperature returned to normal, the lymph node swelling was gradually reduced, and the lung lesion was absorbed.

Conclusion

We report the first case of an HIV-negative patient diagnosed with disseminated M. fortuitum and T. marneffei coinfection with nonspecific clinical manifestation, in order to heighten awareness of these infections.

Talaromyces marneffei and nontuberculous mycobacteria co-infection in HIV-negative patients

To describe the clinical features and the risk factors for nontuberculous mycobacteria (NTM) and Talaromyces marneffei (TM) co-infections in HIV-negative patients. A multicenter retrospective study in 13 hospitals, and a systematic literature review were performed of original articles published in English related to TM/NTM co-infections. HIV-negative patients with TM and NTM co-infections comprised Group 1; TM-only infection Group 2; NTM-only infection Group 3; and healthy volunteers Group 4. Univariate logistic analysis was used to estimate the potential risk factors of TM/NTM co-infections. A total of 22 cases of TM and NTM co-infections were enrolled. Of these, 17 patients (77.3%) had a missed diagnosis of one of the TM or NTM pathogens. The anti-IFN-γ autoantibodies (AIGAs) titer, white blood cell (WBC), neutrophil counts (N), erythrocyte sedimentation rate (ESR), C reactive protein (CRP), globulin, and immunoglobulin G (IgG) levels of Group 1 were higher than those of the other groups, whereas the levels of CD4⁺T cells was lower than those of other groups. There was a significant negative correlation between the AIGA titers and the number of CD4⁺T cells (P < 0.05). Factors including the ratio of the actual values to the cut-off values of AIGAs, WBC, N, HGB, CD4⁺T cells, IgG, IgM, IgA, serum globulin, ESR, and CRP were taken as potential risk factors for TM and NTM co-infection. Most patients with TM and NTM co-infection had a missed diagnosis of one of the TM or NTM pathogens. The levels of AIGAs, WBC, N, ESR, and CRP in TM and NTM co-infections were remarkably higher than in mono-infection. High-titer AIGAs may be a potential risk factor and susceptibility factor for co-infection of TM and NTM in HIV-negative hosts.

Clinical findings of Talaromyces marneffei infection among patients with anti-interferon-γ immunodeficiency: a prospective cohort study

Background

Talaromyces marneffei (T. marneffei) infection has been associated with adult-onset immunodeficiency due to anti-IFN-γ autoantibodies. We aimed to investigate the clinical features of non-HIV-infected patients with T. marneffei infection in southern China.

Methods

Between January 2018 and September 2020, we enrolled patients with T. marneffei infection who were HIV-negative (group TM, n = 42), including anti-IFN-γ autoantibody-positive (group TMP, n = 22) and anti-IFN-γ autoantibody-negative (group TMN, n = 20) patients and healthy controls (group HC, n = 40). Anti-IFN-γ autoantibodies were detected by ELISA. Clinical characteristics and clinical laboratory parameters were recorded.

Results

Compared with anti-IFN-γ autoantibody-negative patients with T. marneffei infection, anti-IFN-γ autoantibody-positive patients did not have underlying respiratory disease; more frequently exhibited dissemination of systemic infections with severe pleural effusion; had higher WBC counts, C-reactive protein levels, erythrocyte sedimentation rates, and neutrophil and CD8⁺ T cell counts; had lower hemoglobin levels; and were more likely to have other intracellular pathogen infections. Most of these patients had poor outcomes despite standardized antimicrobial therapy.

Conclusion

T. marneffei-infected patients with higher anti-IFN-γ autoantibody titers have more severe disease and complex clinical conditions.

Opportunist Coinfections by Nontuberculous Mycobacteria and Fungi in Immunocompromised Patients

Nontuberculous mycobacteria (NTM) and many fungal species (spp.) are commonly associated with opportunistic infections (OPIs) in immunocompromised individuals. Moreover, occurrence of concomitant infection by NTM (mainly spp. of Mycobacterium avium complex and Mycobacterium abscessus complex) and fungal spp. (mainly, Aspergillus fumigatus, Histoplasma capsulatum and Cryptococcus neoformans) is very challenging and is associated with poor patient prognosis. The most frequent clinical symptoms for coinfection and infection by single agents (fungi or NTM) are similar. For this reason, the accurate identification of the aetiological agent(s) is crucial to select the best treatment approach. Despite the significance of this topic it has not been sufficiently addressed in the literature. This review aims at summarizing case reports and studies on NTM and fungi coinfection during the last 20 years. In addition, it briefly characterizes OPIs and coinfection, describes key features of opportunistic pathogens (e.g., NTM and fungi) and human host predisposing conditions to OPIs onset and outcome. The review could interest a wide spectrum of audiences, including medical doctors and scientists, to improve awareness of these infections, leading to early identification in clinical settings and increasing research in the field. Improved diagnosis and availability of therapeutic options might contribute to improve the prognosis of patients' survival.