In vitro interactions of calcineurin inhibitors with conventional antifungal agents against the yeast form of Penicillium marneffei

Bio-preservatives and essential oils as an alternative to chemical preservatives in the baking industry: a concurrent review

The use of chemical preservatives in the baking industry is a common practice to extend the shelf life of baked goods However, there is growing interest in natural alternatives due to worries about the security and potential health risks of these chemicals. The purpose of this concurrent review is to investigate the potential of using essential oils and bio-preservatives in place of chemical preservatives in the baking industry. With a focus on their efficiency in extending the shelf life of baked goods, the review includes a thorough analysis of the most recent research on the use of bio-preservatives and essential oils in food preservation. The findings suggest that bio-preservatives and essential oils can be effective in preserving baked goods and may offer a safer and more natural alternative to chemical preservatives. However, further research is needed to fully understand the potential of these natural alternatives and to optimize their use in the baking industry.

Talaromycosis from Wuhan: two-case report and literature review

Background

Talaromycosis is a serious opportunistic infectious disease caused by Talaromyces marneffei, which mostly occurs in immunocompromised patients. The disease is mainly prevalent in tropical countries and regions of Southeast Asia and South Asia, but non-endemic areas also have patients with Talaromycosis. The disease has no characteristic clinical manifestations and is difficult to diagnose. Delayed diagnosis often leads to death.

Case presentation

Both patients had cellular immunodeficiency. Case 1 had a history of acquired immune deficiency syndrome, and case 2 had a history of renal transplantation and glucose-6-phosphate dehydrogenase deficiency. They all had fever, anemia, fatigue, and skin lesions. Case 1 had gastrointestinal bleeding, enlarged lymph nodes, and hepatosplenomegaly. Case 2 had cough and dyspnea. Both patients had thrombocytopenia and hypoalbuminemia; an increased neutrophil ratio, procalcitonin, and C-reactive protein; and abnormal liver function and coagulation dysfunction. Case 1 sputum culture, blood culture, and bronchoalveolar lavage fluid were positive for T. marneffei. T. marneffei was detected in the blood culture of case 2, with infection of Candida parapsilosis and Pneumocystis jirovecii. Chest computed tomography scan mainly showed pulmonary exudative lesions. Although these two patients were actively treated, they died of poor efficacy.

Conclusion

Talaromycosis has an insidious onset, long course, atypical clinical symptoms, imaging performance and laboratory results, difficult diagnosis, and high mortality. Therefore, it is important to promptly consider and treat Talaromycosis in immunocompromised patients upon infection in order to reduce mortality.

Development and validation of a colorimetric antifungal susceptibility testing method for the dimorphic fungus Talaromyces marneffei

Antifungal drug resistance is an emerging cause of treatment failure in invasive fungal infections, and antifungal susceptibility testing (AFST) may inform treatment decisions. Currently, there are no established AFST guidelines for Talaromyces marneffei (Tm) or other dimorphic fungi. We developed a colorimetric AFST method using a fluorescent redox indicator alamarBlue, which changes from blue to pink in proportion to cellular metabolic activity. We determined the optimal time for alamarBlue addition to be 24 h post-inoculation and for MIC reading to be 72 h post-inoculation. Our method allows three ways to determine minimum inhibitory concentration (MIC): visual inspection of color change, optical density, and fluorescence intensity. We validated the assay by determining the MICs for seven antifungals against 32 Tm clinical isolates and assessed the essential agreement (EA) and inter-rater reliability between our alamarBlue and the Clinical Laboratory Standard Institute (CLSI) broth microdilution methods. The MIC ranges (from low to high) were: 0.008-0.025 μg/ml for itraconazole, 0.004-0.13 μg/ml for voriconazole, 0.03-0.13 μg/ml for posaconazole, 0.06-0.5 µg/ml for flucytosine, 0.5-1 µg/ml for amphotericin B, 0.5-4 µg/ml for caspofungin, and 0.5-16 µg/ml for fluconazole. The EAs were 100% between all three MIC readouts of the alamarBlue method, and 94%-100% between the alamarBlue and CLSI methods. Our alamarBlue method had substantially higher inter-rater agreement and offers a more reliable method that can be standardized across laboratories in both high- and low-resource settings compared to the established CLSI methodology.

A Retrospective Study of Clinical and Immunological Features of a Pediatric Population with Talaromyces marneffei Infection

BACKGROUND

Talaromyces marneffei (T. Marneffei) infection is considered as an indicator of immunosuppression in immunocompromised individuals, leading to multiple organ damage. Our study aimed to evaluate both the clinical characteristics and immunological features of pediatric patients infected with T. marneffei from our institute, providing novel insights into diagnosis and treatment for this life-threatening disease.

METHOD

Thirteen pediatric patients with T. marneffei infection were enrolled in Guangzhou Women and Children's Medical Center during 2012 to 2020. Clinical data and laboratory findings were collected and further analyzed. Pearson correlation coefficient was calculated to determine the relationship between serum immunoglobulins (Igs) levels and white blood cell count, or the absolute lymphocyte count.

RESULTS

Patients were diagnosed as having T. Marneffei infection mainly based on the results of fungal culture and Gram stain of specimens. The most common presentations were fever (69%), pneumonia (38%) and immunodeficiency (38%). The total levels of Igs (IgE, IgA, and IgM) were positively correlated with both white blood cell count and absolute lymphocyte count.

CONCLUSION

Serum Ig expression Pattern in patients diagnosed with T. marneffei infection might serve as an effective prognostic marker which would help with the development of early interventions for children with this fatal disease.

Study on the mechanisms of action of berberine combined with fluconazole against fluconazole-resistant strains of Talaromyces marneffei

Talaromyces (Penicillium) marneffei (T. marneffei) is a thermally dimorphic fungus that can cause opportunistic systemic mycoses. Our previous study demonstrated that concomitant use of berberine (BBR) and fluconazole (FLC) showed a synergistic action against FLC-resistant T. marneffei (B4) in vitro. In this paper, we tried to figure out the antifungal mechanisms of BBR and FLC in T. marneffei FLC-resistant. In the microdilution test, the minimum inhibitory concentration (MIC) of FLC was 256 μg/ml before FLC and BBR combination, and was 8 μg/ml after combination, the partial inhibitory concentration index (FICI) of B4 was 0.28. After the treatments of BBR and FLC, the studies revealed that (i) increase reactive oxygen species (ROS), (ii) reduce ergosterol content, (iii) destroy the integrity of cell wall and membrane, (iv) decrease the expression of genes AtrF, MDR1, PMFCZ, and Cyp51B however ABC1 and MFS change are not obvious. These results confirmed that BBR has antifungal effect on T. marneffei, and the combination with FLC can restore the susceptibility of FLC-resistant strains to FLC, and the reduction of ergosterol content and the down-regulation of gene expression of AtrF, Mdr1, PMFCZ, and Cyp51B are the mechanisms of the antifungal effect after the combination, which provides a theoretical basis for the application of BBR in the treatment of Talaromycosis and opens up new ideas for treatment of Talaromycosis.

Calcineurin A Is Essential in the Regulation of Asexual Development, Stress Responses and Pathogenesis in Talaromyces marneffei

Talaromyces marneffei is a common cause of infection in immunocompromised patients in Southeast Asia and Southern China. The pathogenicity of T. marneffei depends on the ability of the fungus to survive the cytotoxic processes of the host immune system and grow inside host macrophages. These mechanisms that allow T. marneffei to survive macrophage-induced death are poorly understood. In this study, we examined the role of a calcineurin homolog (cnaA) from T. marneffei during growth, morphogenesis and infection. Deletion of the cnaA gene in T. marneffei resulted in a strain with significant defects in conidiation, germination, morphogenesis, cell wall integrity, and resistance to various stressors. The ΔcnaA mutant showed a lower minimal inhibitory concentration (MIC) against caspofungin (16 μg/ml to 2 μg/ml) and micafungin (from 32 μg/ml to 4 μg/ml) compared with the wild-type. These results suggest that targeting calcineurin in combination with echinocandin treatment may be effective for life-threatening systemic T. marneffei infection. Importantly, the cnaA mutant was incapable of adapting to the macrophage environment in vitro and displayed virulence defects in a mouse model of invasive talaromycosis. For the first time, a role has been shown for cnaA in the morphology and pathogenicity of a dimorphic pathogenic filamentous fungus.

Rapid and precise diagnosis of T. marneffei pulmonary infection in a HIV-negative patient with autosomal-dominant STAT3 mutation: a case report

BACKGROUND

Talaromyces marneffei, also named Penicillium marneffei, is an opportunistic pathogen that can cause systemic or limited infection in human beings. This infection is especially common in human immunodeficiency virus (HIV)-infected hosts; however, it has also been recently reported in HIV-negative hosts. Here, we report a very rarely seen case of T. marneffei pulmonary infection in a non-HIV-infected patient with signal transducer and activator of transcription 3 (STAT3) mutation.

CASE PRESENTATION

A 34-year-old woman was admitted to our hospital for uncontrollable nonproductive cough and dyspnea with exercise. She had been immunocompromised since infancy. Computerized tomography scan showed multiple ground glass opacities with multiple bullae in both lungs. Next generation sequencing (NGS) of the bronchoalveolar lavage fluid identified T. marneffei nucleotide sequences. Culture of bronchoscopy specimens further verified the results. The patient was HIV negative, and blood gene detection indicated STAT3 mutation. To date, following the application of itraconazole, the patient has recovered satisfactorily.

CONCLUSION

In clinical practice, T. marneffei infection among HIV-negative individuals is relatively rare, and we found that patients who are congenitally immunocompromised due to STAT3 mutation may be potential hosts. Early diagnosis and timely treatment are expected to improve the prognosis of T. marneffei infection. NGS is a powerful technique that may play an important role in this progress. The reviews of this paper are available via the supplemental material section.

In Vitro Susceptibility of Berberine Combined with Antifungal Agents Against the Yeast Form of Talaromyces marneffei

Talaromyces (Penicillium) marneffei can cause fatal disseminated infection in immunocompromised hosts. However, therapeutic strategies for the mycosis are limited. Reports of the other fungi suggest that berberine, a component of traditional herb, inhibitors interact with antifungal agents to improve the treatment outcomes. In the study, we evaluated the in vitro efficacy of berberine in combination with conventional antifungal agents against the pathogenic yeast form of T. marneffei. We demonstrate the synergistic effect of combination of berberine with fluconazole (52.38%), itraconazole (66.67%), voriconazole (71.43%), amphotericin B (71.43%) or caspofungin (52.38%) of T. marneffei strains, respectively. Time-kill curves confirmed the synergistic interaction, and no antagonistic was observed in all of the combinations. In conclusion, berberine could enhance the efficacy of conventional antifungal agents against the yeast form of T. marneffei in vitro. The results indicated berberine might have a potential role in combination therapy for talaromycosis.

Administration of Voriconazole in Disseminated Talaromyces (Penicillium) Marneffei Infection: A Retrospective Study

Talaromyces (Penicillium) marneffei infection is a fatal disseminated mycosis caused by the dimorphic fungus Talaromyces marneffei; the therapeutic strategies for this infectious disease are limited. The aim of this retrospective study was to evaluate the efficacy and safety of voriconazole for treating patients with disseminated T. marneffei infection with or without HIV infection in a clinical setting. Patients who intravenously received voriconazole (6 mg/kg q12 h for the first 24 h followed by 4 mg/kg q12 h) as the initial antifungal treatment were enrolled. The duration of the following antifungal treatment varied at the discretion of the investigators according to the patient responses. The primary global response was evaluated at Week 16 or at the end of treatment (EOT). Follow-up evaluations were performed at 6 months and 1 year after the EOT. Seventeen patients were enrolled in this study, but three were not evaluable because the treatment was prematurely discontinued. Among the remaining fourteen patients, ten patients had complete response and three had partial response at Week 16. Only one patient was determined to have failed response. Follow-up assessments in eleven patients showed that eight patients were cured and the remaining three patients relapsed at 6 months after the EOT. These eight patients were assessed 1 year later, and none of them had relapsed. No adverse events associated with voriconazole were recorded during the treatment. The results from our study suggest that voriconazole is an effective, well-tolerated therapeutic option for disseminated T. marneffei infection.

Retrospective analysis of 15 cases of Penicillium marneffei infection in HIV-positive and HIV-negative patients

Penicillium marneffei (P. marneffei) causes systemic opportunistic infections in immunocompromised individuals, particularly in those infected with human immunodeficiency virus (HIV), and more rarely in HIV-negative patients. We retrospectively analyzed the cases of 15 patients infected with P. marneffei. The patients were divided into two groups: HIV-negative (n = 4) and HIV-positive (n = 11). Of the cases studied, three (75%) of the HIV-negative and six (55%) of the HIV-positive group had an accompanying lung infection. The ratio of CD4⁺/CD8⁺ was 1.2 (SD = 0.99) in the HIV-negative group and 0.10 (SD = 0.095) in the HIV-positive patients. A series of laboratory examinations were performed and bone marrow smears were observed after staining. P. marneffei is a disseminated fungal infection associated with severe disease symptoms and high mortality rates. Our findings indicate that timely diagnosis and treatment by clinicians is crucial for preventing the spread of localized infections into systemic infections, thereby improving the prognosis of patients.

A Retrospective Analysis of 7 Human Immunodeficiency Virus-Negative Infants Infected by Penicillium marneffei

Infection with Penicillium marneffei has rarely been reported in human immunodeficiency virus (HIV)-negative infants. We aimed to determine the epidemiological, clinical, pathological, and immunological characteristics of 7 HIV-negative infants infected by P. marneffei, and to provide insights into its diagnosis and treatment.We retrospectively reviewed the cases of 7 HIV-negative infants infected by P. marneffei who presented to the First Affiliated Hospital of Guangxi Medical University between January 1, 2003 and December 1, 2014. The infants' median age was 23.43 months (SD = 8.34), and all lived in Guangxi Province in China, where P. marneffei is endemic. The median time from disease onset to diagnosis was 2.29 months (SD = 2.12). Of the cases studied, 5 (71.43%) had medical histories that included frequent pneumonia or bronchopneumonia, thrush, congenital megacolon, glucose-6-phosphate dehydrogenase deficiency, and hemophagocytic syndrome. The most common symptoms were fever, cough, and anemia, followed by lymphadenopathy, hepatosplenomegaly, and being underweight. Four patients had slightly elevated white blood cell counts. The lymphocyte and CD4 T-cell counts were normal. The CD8 T-cell counts, serum immunoglobulin (Ig) G titer, and serum IgA titer were low in 5 patients, and the serum IgM titers were high in 3 infants. Caseous necrosis was observed in 3 patients whose lymph nodes were affected. One case who received intravenous amphotericin B and 3 cases who received intravenous voriconazole improved, and these patients were cured after continual treatment with oral voriconazole for 6 or 12 months. The remaining patients died before they received antifungal treatment.P. marneffei causes severe disease and disseminated infections, and it has high mortality rates in HIV-negative infants in endemic areas. P. marneffei susceptibility may be associated with immunodeficiencies or immune disorders. In endemic areas, clinicians should aware of disseminated P. marneffei infections when infants present with serious or recurrent infections, even if they are HIV negative. P. marneffei is highly susceptible to amphotericin B and voriconazole. Timely diagnosis and treatment can improve patients' prognoses. Intravenous voriconazole could be recommended as the initial antifungal agent for HIV-negative infants infected by P. marneffei, because of its low nephrotoxicity, high sensitivity, and high efficacy levels.