Cytological diagnosis of Penicillium marneffei infection

Analysis of clinical characteristics and prognosis of talaromycosis (with or without human immunodeficiency virus) from a non-endemic area: a retrospective study

Purpose

Talaromyces marneffei (TM) is a pathogenic fungus endemic in Southeast Asia and human immunodeficiency virus (HIV)-positive populations, but studies related to non-endemic areas and HIV-negative populations are still limited. Therefore, this study aims to provide more additional evidence for clinical work of talaromycosis.

Methods

To collect clinical information of patients with talaromycosis admitted to hospitals in Zhejiang Province, China from January 1, 2010 to May 31, 2020, retrospectively analyzed clinical characteristics and prognosis, COX multivariate regression analysis was used for survival analysis.

Results

A total of 92 patients were enrolled, including 76 males, 73 HIV-positive patients, with an average age of 40.1 ± 13.0. Compared to HIV-positive group, the negative group had higher admission age (47.7 ± 14.6 vs 38.1 ± 11.9, p = 0.003) and lower proportion of male (89.0% vs 57.9%, p = 0.004), there was no significant difference in imaging of lungs. There were significantly more HIV-positive patients in those with pleural effusion (100% vs 69.4%, p = 0.001). COX multivariate regression analysis suggested pleural effusion (HR = 3.220; 95% CI 1.117–9.287; p = 0.030) and HIV infection (HR = 0.057; 95% CI 0.009–0.370; p = 0.003) which were independent predictors of prognosis in patients with talaromycosis.

Conclusions

In non-endemic areas, clinical symptoms, signs, and laboratory tests of patients with talaromycosis are similar to those in endemic areas. Patients with pleural effusion have lower survival rate, HIV-infected people are less likely to relapse, and there is no significant correlation between extent of lung involvement and survival of infected patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s15010-021-01679-6.

Diagnosis of Pulmonary Infections Due to Endemic Fungi

Endemic mycoses including Histoplasma, Blastomyces, Coccidioides, Paracoccidioides, and Talaromyces are dimorphic fungi that can cause a variety of clinical manifestations, including respiratory infections. Their pulmonary presentations are variable, and diagnosis is often delayed as they can mimic other infectious and non-infectious causes of pulmonary disease. Delay in diagnosis can lead to unnecessary antibiotic use, repeat hospitalizations, and increased morbidity and mortality. The diagnosis of endemic fungal pulmonary infections often relies on multiple diagnostic tests including culture, tissue histopathology, antigen assays, and antibody assays. Due to the increased use of immunosuppressive agents and the widening geographic ranges where these infections are being found, the prevalence of endemic fungal infections is increasing. Physicians need to be aware of the clinical manifestations of pulmonary infections due to endemic fungal in order to ensure that the proper diagnostic work up is obtained promptly. A high index of suspicion is particularly important in patients with suspected pulmonary infections who have failed to improve despite antibiotics in the appropriate setting. We present a review diagnostic testing for pulmonary infections due to endemic mycoses.

Determinants of prognosis in Talaromyces marneffei infections with respiratory system lesions

Background:

Little study has investigated the differences between Talatomyces marneffei (T. marneffei) respiratory infection and tuberculosis and the prognostic factors of such infection. This study investigated the characteristics and prognostic factors of T. marneffei infections with respiratory lesions and the causes of misdiagnosis.

Methods:

Clinical characteristics and prognoses of patients with T. marneffei infections with respiratory system lesion were investigated. T. marneffei diagnosis followed isolation from clinical specimens using standard culture, cytology, and histopathology. Survival curves were estimated by using Kaplan-Meier analysis, with log-rank test to compare differences in survival rates between groups. Univariate and multivariate Cox regression analyses were also performed to assess significant differences in clinical characteristics of overall survival.

Results:

Of 126 patients diagnosed with T. marneffei infections, 63 (50.0%) had T. marneffei respiratory system infections; 38.1% (24/63) were misdiagnosed as having tuberculosis. Human immunodeficiency virus (HIV) infection, CD4/CD8 < 0.5, percentage of CD4⁺ T cells <42.8%, and length of time from onset to confirmation of diagnosis >105 days were potential risk factors for poor prognoses. Length of time from onset to confirmation of diagnosis persisted as an independent predictor of all-cause mortality in multivariate analysis (odds ratio: 0.083, 95.0% confidence interval: 0.021–0.326, P < 0.001). However, the size of the lung lesions, dyspnea, thoracalgia, mediastinal lymphadenopathy, and pleural effusion did not significantly predict overall survival. There was no significant difference in prognosis according to the type of treatment.

Conclusions:

T. marneffei infections involving the respiratory system are common. The critical determinants of prognosis are HIV infection, CD4/CD8, percentage of CD4⁺ T cells, type of treatment, and the time range from onset to confirmation of diagnosis. Rapid and accurate diagnosis is crucial for improving prognosis.

Accuracy of rapid diagnosis of Talaromyces marneffei: A systematic review and meta-analysis

Background

To examine the accuracy of Rapid Diagnosis of Talaromyces marneffei (RDTM) in order to improve diagnosis and treatment for clinical measures and reduce the mortality due to associated infections.

Methods

In this systematic review and meta-analysis, we screened PubMed, Ovid (Cochrane library) and Web of Science, Chinese database CNKI and Wanfang for articles published between 1956 and December, 2017. Data were taken from cross-sectional studies as well as from baseline measurements in longitudinal studies with clinical follow-up. Articles were excluded if they did not contain a cohort with T. marneffei and a control cohort or a cohort with standard fungus culture. Data were extracted by two authors and checked by three for accuracy. For quality assessment, modified QUADAS-2 criteria were used.

Results

The 26 included diagnostic studies enrolled 5,594 objectives in 632 patients with T. marneffei infections and 2,612 negative controls between 1996 and 2017 in Thailand, Vietnam and China. The total combined sensitivity and specificity of rapid diagnosis of T. marneffei was 0.82 (95% CI: 0.68–0.90) and 0.99 (95% CI: 0.98–1.00). According to the experimental method, the included studies can be divided into three subgroups, including PCR-based, ELISA-based and others. The results showed these three subgroups had a highly pooled specificity of 1.00 (95% CI: 0.99–1.00), 0.99 (0.98–1.00) and 0.97 (95% CI: 0.91–1.00), respectively, while combined sensitivity was 0.84 (95% CI: 0.37–0.98), 0.82 (95% CI: 0.64–0.92) and 0.77 (95% CI: 0.54–0.91), respectively.

Conclusions

Although serological methods with a high specificity is essential for potential rapid diagnostic, false-negative results can be obtained in the serum samples, there is no suitable rapid serological test to refer to as is the case with TM infection.

Penicillium marneffei infection in a HIV-Positive patient: A comparison of bronchial washing cytology and biopsy

Penicilliosis is a disseminated and progressive infection that is mainly found in immunocompromised individuals, especially those with human immunodeficiency virus (HIV) infection. Because of the high mortality of patients with disseminated Penicillium marneffei infection, rapid diagnosis and early treatment are required. Diagnosis is traditionally made by biopsy and/or culture of blood or any involved organ. Cytology offers several advantages over biopsy, including more rapid diagnosis and greater resolution of cytomorphologic details of organisms, allowing rapid initiation of treatment. Here, we describe a case of penicilliosis in an HIV-positive patient with emphasis on the morphological characteristics of the organism in cytologic specimens, as well as a comparison of bronchial washing and biopsy findings.

Talaromyces (Penicillium) marneffei infection in non-HIV-infected patients

Talaromyces (Penicillium) marneffei is an important pathogenic thermally dimorphic fungus causing systemic mycosis in Southeast Asia. The clinical significance of T. marneffei became evident when the human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome epidemic arrived in Southeast Asia in 1988. Subsequently, a decline in the incidence of T. marneffei infection among HIV-infected patients was seen in regions with access to highly active antiretroviral therapy and other control measures for HIV. Since the 1990s, an increasing number of T. marneffei infections have been reported among non-HIV-infected patients with impaired cell-mediated immunity. Their comorbidities included primary adult-onset immunodeficiency due to anti-interferon-gamma autoantibodies and secondary immunosuppressive conditions including other autoimmune diseases, solid organ and hematopoietic stem cell transplantations, T-lymphocyte-depleting immunsuppressive drugs and novel anti-cancer targeted therapies such as anti-CD20 monoclonal antibodies and kinase inhibitors. Moreover, improved immunological diagnostics identified more primary immunodeficiency syndromes associated with T. marneffei infection in children. The higher case-fatality rate of T. marneffei infection in non-HIV-infected than HIV-infected patients might be related to delayed diagnosis due to the lack of clinical suspicion. Correction of the underlying immune defects and early use of antifungals are important treatment strategies. Clinicians should be familiar with the changing epidemiology and clinical management of T. marneffei infection among non-HIV-infected patients.

Disseminated Talaromyces marneffei and Mycobacterium intracellulare coinfection in an HIV-infected patient

A 25-year-old man with human immunodeficiency virus (HIV) infection presented with fever that had lasted 1 month. The CD4+ T lymphocyte count was 7 cells/μL and computed tomography showed several small lung nodules, splenomegaly, and multiple lymphadenopathy. Talaromyces marneffei was isolated in the initial blood cultures. As the fever persisted despite clearance of fungemia and 10 days of liposomal amphotericin B treatment, cervical lymph node fine-needle aspiration was performed. Mycobacterium intracellulare was isolated from sputum and neck node aspiration cultures. The patient was successfully treated with liposomal amphotericin B, clarithromycin, and ethambutol in addition to antiretroviral therapy. This case suggests that we should consider coinfection of opportunistic pathogens in febrile immunosuppressed patients if the patient does not respond properly to the initial treatment.

A case of Penicillium marneffei infection involving the main tracheal structure

Background

Penicillium marneffei is the only dimorphic member of the genus and is an emerging pathogenic fungus that can cause fatal systemic mycosis. Penicillium marneffei disseminates hematogenously to other locations. Penicillium marneffei infection most commonly involves the skin, lungs, and reticuloendothelial system, including the bone, bone marrow, joints, lymph nodes, pericardium, liver, and spleen. Involvement of the mesenteric and central nervous systems has also been reported. Infection involving the trachea has not been previously reported.

Case presentation

We herein report a previously healthy 28-year-old male farmer from Guangxi Province without HIV who became infected with P. marneffei. The infection primarily affected the trachea, resulting in structural damage to the cartilage, tracheal stenosis, and tracheal absence. The infection also involved the lungs and lymph nodes. After antifungal treatment and surgery, his symptoms, signs, and lung imaging findings showed significant improvement. This is the first such case report.

Conclusion

Penicillium marneffei infection in normal hosts is characterized by an insidious onset, various clinical manifestations, and common misdiagnosis, leading to high mortality rates. Penicillium marneffei hematogenously disseminates throughout the whole body. This is the first reported case of P. marneffei infection involving the main trachea with subsequent structural damage to the tracheal cartilage, severe tracheostenosis, and tracheal absence.

Penicillium marneffei Infection in AIDS

Penicillium marneffei is a dimorphic fungus which is endemic in Southeast Asia. It is an opportunistic pathogen which has emerged to become an AIDS-defining illness in the endemic areas. Early diagnosis with prompt initiation of treatment is crucial for its management. Prompt diagnosis can often be established through careful cytological and histological examination of clinical specimens although microbiological culture remains the gold standard for its diagnosis. Standard antifungal treatment for AIDS patients with penicilliosis is well established. Highly active antiretroviral therapy should be started early together with the antifungal treatment. Special attention should be paid to potential drug interaction between antiretroviral and antifungal treatments. Secondary prophylaxis may be discontinued with a low risk of relapse of the infection once the immune dysfunction has improved.

An imprint method for detecting leptospires in the hamster model of vaccine-mediated immunity for leptospirosis

In determining the efficacy of new vaccine candidates for leptospirosis, the primary end point is death and an important secondary end point is sterilizing immunity. However, evaluation of this end point is often hampered by the time-consuming demands and complexity of methods such as culture isolation (CI). In this study, we evaluated the use of an imprint (or touch preparation) method (IM) in detecting the presence of leptospires in tissues of hamsters infected with Leptospira interrogans serovar Copenhageni. In a dissemination study, compared to CI, the IM led to equal or improved detection of leptospires in kidney, liver, lung and blood samples collected post-infection and overall concordance was good (kappa=0.61). Furthermore, in an evaluation of hamsters immunized with a recombinant leptospiral protein-based vaccine candidate and subsequently challenged, the agreement between the CI and IM was very good (kappa=0.84). These findings indicate that the IM is a rapid method for the direct observation of Leptospira spp. that can be readily applied to evaluating infection in experimental animals and determining sterilizing immunity when screening potential vaccine candidates.