Investigation of dogs as a reservoir of Penicillium marneffei in northern Thailand

Advances in the understanding of talaromycosis in HIV-negative patients (especially in children and patients with hematological malignancies): A comprehensive review

Talaromyces marneffei (T. marneffei) stands out as the sole thermobiphasic fungus pathogenic to mammals, including humans, within the fungal community encompassing Ascomycota, Eurotium, Eurotiumles, Fungiaceae, and Cyanobacteria. Thriving as a saprophytic fungus in its natural habitat, it transitions into a pathogenic yeast phase at the mammalian physiological temperature of 37°C. Historically, talaromycosis has been predominantly associated with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS), classified among the three primary opportunistic infections linked with AIDS, alongside tuberculosis and cryptococcosis. As advancements are made in HIV/AIDS treatment and control measures, the incidence of talaromycosis co-infection with HIV is declining annually, whereas the population of non-HIV-infected talaromycosis patients is steadily increasing. These patients exhibit diverse risk factors such as various types of immunodeficiency, malignant tumors, autoimmune diseases, and organ transplantation, among others. Yet, a limited number of retrospective studies have centered on the clinical characteristics and risk factors of HIV-negative talaromycosis patients, especially in children and patients with hematological malignancies, resulting in an inadequate understanding of this patient cohort. Consequently, we conducted a comprehensive review encompassing the epidemiology, pathogenesis, risk factors, clinical manifestations, diagnosis, treatment, and prognosis of HIV-negative talaromycosis patients, concluding with a prospectus of the disease's frontier research direction. The aim is to enhance comprehension, leading to advancements in the diagnosis and treatment rates for these patients, ultimately improving their prognosis.

The Zoonotic Potential of Fungal Pathogens: Another Dimension of the One Health Approach

Zoonotic diseases are caused by viruses, bacteria, fungi and parasites and they comprise about 75% of all emerging infectious diseases. These can be transmitted via the direct (scratches on skin or animal bites) or indirect mode (through environmental shedding of infectious agent by the infected animal) of transmission. Environmental changes, whether in the form of urbanization, industrialization or destruction of wildlife habitats, lead to more human invasion in wildlife areas, subsequently leading to an increased passage of animals towards human dwellings and more exposure to animals, making humans susceptible to these infections. Climate change is another major factor. Global warming and the evolving thermotolerance of fungi, adapting more to human body temperature than their saprophytic nature, is leading to the emergence of humans as new hosts for fungi. The domestication of animals, rising populations, enhanced tourism, migratory populations, intrusions into wildlife, etc., are other known factors. Zoonotic fungal infections have long been neglected and are now gaining due attention. In this review, we briefly discuss the various aspects currently known for zoonotic fungal infections and bring forth the importance of this particular issue to be addressed in a timely manner.

Clinical Diagnostic Challenge in a Case of Disseminated Talaromyces marneffei Infection Misdiagnosed Initially as Pulmonary Tuberculosis: A Case Report and Literature Review

This case reports a middle-aged male patient who was HIV-negative and initially misdiagnosed as pulmonary tuberculosis but was eventually diagnosed with disseminated Talaromyces marneffei (T. marneffei) infection by next-generation sequencing. The patient presented with respiratory symptoms, recurrent bone pain, and subcutaneous masses as the main symptoms. After one year of antifungal treatment, the symptoms improved obviously, but the symptoms recurred after two weeks of drug withdrawal, and the symptoms were relieved after re-administration of antifungal drugs again. This report highlights the need for the rapid evaluation of fungal infections with metagenomic next-generation sequencing (mNGS) in patients with an inadequate diagnostic basis for tuberculosis infection or a poor response to antituberculosis drugs. In addition, long-term follow-up is needed to observe disease recurrence in patients with disseminated T. marneffei infection.

First morphological and molecular isolation of Talaromyces marneffei in beech marten (Martes foina) in Portugal

Talaromyces marneffei is a zoonotic fungus that mostly infects immunocompromised individuals. For the first time, this fungus was isolated in an adult beech marten (Martes foina) hit by a car, found dead in Penamacor, Portugal. During the necropsy, different samples (skin, fur, lymph nodes, lung, spleen, kidneys, and brain) were collected and processed for microbiology (including mycology) and molecular biology. T. marneffei was identified through its mycological characteristics and confirmed by PCR in hair samples. No other lesions or alterations were reported, except a concomitant presence of M. avium subsp. paratuberculosis in lung, kidney and brain samples. To the authors' knowledge, this is the first description of this fungus beech marten, as well as the first case of co-infection with M. avium subsp. paratuberculosis in wildlife fauna. These results suggest a sylvatic life-cycle of T. marneffei, involving beech martens, in Portugal.

Identification of Talaromyces marneffei Infection in an HIV-Negative Patient by ITS Sequencing

Disseminated ankle mycosis is a life-threatening systemic infection caused by the emerging opportunistic and lethal fungal pathogen Talaromyces marneffei which is more common in HIV-positive patients. However, an increasing number of infections are occurring in HIV-negative patients. Here, we report a case of Talaromyces marneffei infection in HIV-negative patient. A 50s HIV-negative male patient with fever, cough, bloody sputum expectoration, pulmonary sarcoidosis and body rashes was hospitalized at Zhejiang Provincial People's Hospital. CT scanning showed pulmonary multiple nodules with apical bronchial occlusion, patchy infiltration and pathological biopsy demonstrated bronchiolitis obliterans with organized pneumonia and chronic active inflammation of lung tissue with infiltration of numerous lymphocytes, plasma cells, phagocytes and neutrophils. Laboratory tests revealed significantly increased white blood cells count 18.3 ×109/L, neutrophil count 15.34 ×109/L, monocyte count 0.66 ×109/L, platelet count 517 ×109/L, C-reactive protein 116 mg/L, erythrocyte sedimentation rate 112mm/h. The β-D-glucan test was negative (33.06 pg/mL) while fungal culture of broncho alveolar lavage fluid revealed colonies with temperature-dependent dimorphic growth character and Talaromyces marneffei was confirmed by ITS sequencing of the colonies. The patient exhibited radiological improvement and clinical recuperation after intravenously guttae of voriconazole. Talaromycosis in immunocompetent and HIV-negative individuals is relatively rare and is characterized by an insidious onset, various clinical manifestations, and is clinically challenging. Fungal culture and ITS sequencing are warranted for diagnosis Talaromyces marneffei infection. This is the first report on identification of Talaromyces marneffei infection in an HIV-negative patient with skin involvement by ITS sequencing in Zhejiang.

An Overlooked and Underrated Endemic Mycosis-Talaromycosis and the Pathogenic Fungus Talaromyces marneffei

Talaromycosis is an invasive mycosis endemic in tropical and subtropical Asia and is caused by the pathogenic fungus Talaromyces marneffei. Approximately 17,300 cases of T. marneffei infection are diagnosed annually, and the reported mortality rate is extremely high (~1/3). Despite the devastating impact of talaromycosis on immunocompromised individuals, particularly HIV-positive persons, and the increase in reported occurrences in HIV-uninfected persons, diagnostic and therapeutic approaches for talaromycosis have received far too little attention worldwide. In 2021, scientists living in countries where talaromycosis is endemic raised a global demand for it to be recognized as a neglected tropical disease. Therefore, T. marneffei and the infectious disease induced by this fungus must be treated with concern. T. marneffei is a thermally dimorphic saprophytic fungus with a complicated mycological growth process that may produce various cell types in its life cycle, including conidia, hyphae, and yeast, all of which are associated with its pathogenicity. However, understanding of the pathogenic mechanism of T. marneffei has been limited until recently. To achieve a holistic view of T. marneffei and talaromycosis, the current knowledge about talaromycosis and research breakthroughs regarding T. marneffei growth biology are discussed in this review, along with the interaction of the fungus with environmental stimuli and the host immune response to fungal infection. Importantly, the future research directions required for understanding this serious infection and its causative pathogenic fungus are also emphasized to identify solutions that will alleviate the suffering of susceptible individuals worldwide.

A novel chemical marker of tremorgenic mycotoxicosis detected by gas-chromatography/mass-spectrometry

Tremorgenic mycotoxicosis can arise from dietary exposure to secondary metabolite products of various fungal species, particularly those from the Penicillium genus. Although general toxin screens often rely on gas chromatography-mass spectrometry (GC/MS) and well-developed mass spectral library databases, two principal representative Penicillium mycotoxins, roquefortine and penitrem A, are unamenable to GC/MS owing to high molecular weights, low volatilities and/or high thermal instabilities. Reliance on GC/MS screens alone could therefore inadvertently result in failure to collect evidence of exposure to such tremorgenic mycotoxins. In this report we describe a newly discovered tremorgenic marker compound (TMC), the presence of which correlates highly with conclusive exposure to Penicillium toxins in explanation of clinical manifestations of tremorgenic mycotoxicosis. According to detailed mass spectral deconvolution, the compound is 210.0892 molecular weight, and amenable to GC/MS whether chemically underivatized or derivatized by methylation or trimethylsilylation. 1D and 2D NMR (nuclear magnetic resonance) studies on the isolated compound determined the TMC to be the Penicillium product terrestric acid, C11H14O4, which matches the molecular formula determined by high resolution mass spectrometry and thus provides an excellent target for assessment of mycotoxicosis by GC/MS.

Title of Paper: First case of subcutaneous infection by Talaromyces marneffei in a renal transplant recipient from India and review of literature

Talaromyces marneffei is one of the endemic mycoses prevalent in South-East Asian region. The infection, which was once considered to be opportunistic infection in HIV-positive patients, is establishing foothold in transplant and immunocompetent population. We report a case of a 41-year-old post-renal transplant female with a travel history to Assam two years back presenting with a subcutaneous lesion on right side of scalp associated with pain and blurring of vision in right eye. Fine-needle aspiration from the scalp lesion showed yeast cells with transverse septation in cytological examination and culture grew Talaromyces marneffei, which was confirmed by sequencing of ITS region. Patient was successfully managed with oral itraconazole 200 mg twice daily for ten months without subsequent recurrence. To our knowledge, this is the first case of subcutaneous infection by T. marneffei in a renal transplant recipient from India.

Antifungal Susceptibility Profiles of Olorofim (Formerly F901318) and Currently Available Systemic Antifungals against Mold and Yeast Phases of Talaromyces marneffei

In vitro antifungal susceptibility profiling of 32 clinical and environmental Talaromyces marneffei isolates recovered from southern China was performed against olorofim and 7 other systemic antifungals, including amphotericin B, 5-flucytosine, posaconazole, voriconazole, caspofungin, and terbinafine, using CLSI methodology. In comparison, olorofim was the most active antifungal agent against both mold and yeast phases of all tested Talaromyces marneffei isolates, exhibiting an MIC range, MIC50, and MIC90 of 0.0005 to 0.002 μg/ml, 0.0005 μg/ml, and 0.0005 μg/ml, respectively.

A global view on fungal infections in humans and animals: infections caused by dimorphic fungi and dermatophytoses

Fungal infections are still underappreciated and their prevalence is underestimated, which renders them a serious public health problem. Realistic discussions about their distribution, symptoms, and control can improve management and diagnosis and contribute to refinement of preventive actions using currently available tools. This article represents an overview of dermatophytes and endemic fungi that cause infections in humans and animals. In addition, the impact of climate change on the fungal spread is discussed. The endemic fungal infections characterized in this article include coccidioidomycosis, histoplasmosis, blastomycosis, lobomycosis, emergomycosis and sporotrichosis. Moreover the geographic distribution of these fungi, which are known to be climate sensitive and/or limited to endemic tropical and subtropical areas, is highlighted. In turn, dermatophytes cause superficial fungal infections of skin, hairs and nails, which are the most prevalent mycoses worldwide with a high economic burden. Therefore, the possibility of causing zoonoses and reverse zoonoses by dermatophytes is highly important. In conclusion, the article illustrates the current issues of the epidemiology and distribution of fungal diseases, emphasizing the lack of public programmes for prevention and control of these types of infection.

Analysis of the causes of cervical lymphadenopathy using fine-needle aspiration cytology combining cell block in Chinese patients with and without HIV infection

Background

Cervical lymphadenopathy refers to a frequently observed clinical presentation in numerous pathological conditions. A wide spectrum of diseases can cause cervical lymphadenopathy, irrespective of the fact that the patients are infected with HIV or not. The present study focuses on validating whether the causes of cervical lymphadenopathy differ significantly in HIV and non-HIV patients by using fine-needle aspiration cytology (FNAC) combining cell block.

Methods

A total of 589 patients with cervical lymphadenopathy were recruited in the FNA clinic. The samples were obtained by an auto-vacuumed syringe that benefited the sampling more materials. The cytological smears were prepared by Hematoxylin and Eosin (HE), Periodic Acid Schiff (PAS), Gomori’s methenamine silver (GMS) and acid-fast staining. Cell blocks were made if required, and immunohistochemistry stain was performed on the cell block section.

Results

The study found 453 (76.9%) patients with HIV and 136 (23.1%) patients without HIV infection. The average age of HIV-infected patients was 34.8 ± 10.2 years, which was significantly lower than that of non-HIV-infected patients (42.9 ± 18.1 years) (p < 0.01). Of all patients infected with HIV, 390 (86.1%) were males. This proportion was significantly higher than that of non-HIV-infected patients [65/136 (47.8%)] (p < 0.01). The major causes of cervical lymphadenopathy in HIV positive patients were mycobacterial infection (38.4%), reactive hyperplasia (28.9%), non-specific inflammation (19.9%), and malignant lesions (4.2%). In contrast, the most common causes in HIV negative patients were reactive hyperplasia (37.5%), malignancy (20.6%), non-specific inflammation (19.1%) and mycobacterial infection (12.5%). Opportunistic infections such as non-tuberculous mycobacteria (4.2%), cryptococcosis (1.5%), Talaromyces marneffei (1.5%) and other fungi (0.4%) were found only in HIV-infected individuals. Non-Hodgkin’s lymphoma (2.4%) was the most common malignant lesion in patients with HIV infection, followed by Kaposi’s sarcoma (0.9%) and metastatic squamous cell carcinomas (0.7%). However, the most common malignancy in non-HIV-infected patients was metastatic carcinomas (14%) including small cell carcinomas, adenocarcinomas, squamous cell carcinomas and hepatocellular carcinoma, which were noticeably greater than the HIV patients (p < 0.01).

Conclusions

There were significantly different causes of cervical lymphadenopathy in HIV infected and non-HIV infected patients. FNAC was a useful diagnostic method for differential diagnosis of cervical lymphadenopathy.

Isolation of Talaromyces marneffei from the Skin of an Egyptian Mongoose ( Herpestes ichneumon) in Portugal

We report a case of Talaromyces marneffei skin infection in an Egyptian mongoose ( Herpestes ichneumon) in Portugal. The isolated fungus was identified through its mycologic characteristics, morphology, and PCR amplification.

Pneumonia due to Talaromyces marneffei in a Dog from Southern Brazil with Concomitant Canine Distemper Virus Infection

The pathological and molecular findings associated with Talaromyces marneffei-induced pneumonia with concomitant infection by canine distemper virus (CDV) are described in a dog. The principal pathological alteration occurred in the lungs. Histopathology confirmed multifocal granulomatous pneumonia associated with numerous intralesional and intracellular septate fission cells consistent with T. marneffei. A molecular assay designed to amplify a partial fragment of the 18S rRNA gene of T. marneffei provided positive results from two fungal cultures derived from the lung. Sequencing and phylogenetic analyses confirmed the results of polymerase chain reaction (PCR). Furthermore, antigens of the CDV N protein were identified within the bronchial epithelium by immunohistochemistry and a PCR assay amplified the CDV N gene from hepatic and pulmonary fragments. Collectively, the pathological and molecular techniques confirmed a diagnosis of T. marneffei-induced pneumonia with concomitant infection by CDV. These findings represent the first description of pulmonary penicilliosis in the dog and extend the geographical niche of this emerging infectious pathogen. In this case, infection by CDV may have induced immunosuppression, which facilitated the development of pulmonary penicilliosis.

Neglected fungal zoonoses: hidden threats to man and animals

Zoonotic fungi can be naturally transmitted between animals and humans, and in some cases cause significant public health problems. A number of mycoses associated with zoonotic transmission are among the group of the most common fungal diseases, worldwide. It is, however, notable that some fungal diseases with zoonotic potential have lacked adequate attention in international public health efforts, leading to insufficient attention on their preventive strategies. This review aims to highlight some mycoses whose zoonotic potential received less attention, including infections caused by Talaromyces (Penicillium) marneffei, Lacazia loboi, Emmonsia spp., Basidiobolus ranarum, Conidiobolus spp. and Paracoccidioides brasiliensis.

Clinical, morphological, and molecular characterization of Penicillium canis sp. nov., isolated from a dog with osteomyelitis

Infections caused by Penicillium species are rare in dogs, and the prognosis in these cases is poor. An unknown species of Penicillium was isolated from a bone lesion in a young dog with osteomyelitis of the right ilium. Extensive diagnostic evaluation did not reveal evidence of dissemination. Resolution of lameness and clinical stability of disease were achieved with intravenous phospholipid-complexed amphotericin B initially, followed by long-term combination therapy with terbinafine and ketoconazole. A detailed morphological and molecular characterization of the mold was undertaken. Sequence analysis of the internal transcribed spacer revealed the isolate to be closely related to Penicillium menonorum and Penicillium pimiteouiense. Additional sequence analysis of β-tubulin, calmodulin, minichromosome maintenance factor, DNA-dependent RNA polymerase, and pre-rRNA processing protein revealed the isolate to be a novel species; the name Penicillium canis sp. nov. is proposed. Morphologically, smooth, ovoid conidia, a greenish gray colony color, slow growth on all media, and a failure to form ascomata distinguish this species from closely related Penicillium species.

Spectrums of opportunistic infections and malignancies in HIV-infected patients in tertiary care hospital, China

Background

HIV-related opportunistic infections (OIs) and malignancies continued to cause morbidity and mortality in Chinese HIV-infected individuals. The objective for this study is to elucidate the prevalence and spectrums of OIs and malignancies in HIV-infected patients in the Beijing Ditan Hospital.

Methods

The evaluation of the prevalence and spectrums of OIs and malignancies was conducted by using the clinical data of 834 HIV-infected patients admitted in the Beijing Ditan hospital from January 1, 2009, to November 30, 2012.

Results

The prevalence and spectrums of OIs and malignancies varied contingent on geographic region, transmission routes, and CD4 levels. We found that tuberculosis was most common OI and prevalence was 32.5%, followed by candidiasis(29.3%), Pneumocystis pneumonia(PCP)(22.4%), cytomegalovirus(CMV) infection(21.7%), other fungal infections(16.2%), mycobacterium avium complex(MAC)(11.3%), cryptococcosis(8.0%), progressive multifocal leukoencephalopathy(PML)(4.4%), Cerebral Toxoplasmosis(3.5%) and Penicillium marneffei infection(1.4%); while Lymphoma(2.9%), Kaposi’s sarcoma(0.8%) and cervix carcinoma(0.3%) were emerged as common AIDS-defining malignancies. Pulmonary OI infections were the most prevalent morbidity and mortality in patients in the AIDS stage including pulmonary tuberculosis (26.6%) and PCP (22.4%). CMV infection(21.7%) was most common viral infection; Fungal OIs were one of most prevalent morbidity in patients in the AIDS stage, including oral candidiasis (29.3%), other fungal infection (16.2%), Cryptococcosis (8.0%) and Penicillium marneffei infection (1.4%). We found the low prevalence of AIDS-defining illnesses in central neural system in this study, including progressive multifocal leukoencephalopathy (4.4%), cerebral toxoplasmosis (3.5%), tuberculosis meningitis (3.2%), cryptococcal meningitis (2.4%) and CMV encephalitis (1.1%). In-hospital mortality rate was 4.3 per 100 person-years due to severe OIs, malignancies, and medical cost constraints.

Conclusions

The prevalence and spectrums of OIs, malignancies and co-infections were discussed in this study. It would help increase the awareness for physicians to make a diagnosis and empirical treatment sooner and plan good management strategies, especially in resource limited regions.