Penicilliosis marneffei: another AIDS defining illness in Southeast Asia

Structural, functional, molecular docking analysis of a hypothetical protein from Talaromyces marneffei and its molecular dynamic simulation: an in-silico approach

Telaromyces marneffei (formerly Penicillium marneffei) is an endemic pathogenic fungus in Southern China and Southeast Asia. It can cause disease in patients with travel-related exposure to this organism and high morbidity and mortality in acquired immune deficiency syndrome (AIDS). In this study, we analyzed the structure and function of a hypothetical protein from T. marneffei using several bioinformatics tools and servers to unveil novel pharmacological targets and design a peptide vaccine against specific epitopes. A total of seven functional epitopes were screened on the protein, and 'STGVDMWSV' was the most antigenic, non-allergenic and non-toxic. Molecular docking showed stronger affinity between the CTL epitope 'STGVDMWSV' and the MHC I allele HLA-A*02:01, a higher docking score -234.98 kcal/mol, revealed stable interactions during a 100 ns molecular dynamic simulation. Overall, the results of this study revealed that this hypothetical protein is crucial for comprehending biochemical, physiological pathways and identifying novel therapeutic targets for human health. Communicated by Ramaswamy H. Sarma.

Clinical Characteristics, Laboratory Findings, and Prognosis in Patients With Talaromyces marneffei Infection Across Various Immune Statuses

Objective

Talaromyces marneffei (TM) is an opportunistic fungus that is predominantly prevalent among patients who are HIV-positive in South-East Asia. However, few studies focused on the clinical features, laboratory findings, and prognosis across varying immune states.

Methods

A total of 54 patients with TM infection in Xiangya Hospital of Central South University from January 1, 2006 to October 31, 2021 were retrospectively analyzed. Clinical profiles were compared across the different immune statuses by HIV-positive (HIV group, n = 18), HIV negative but with immunocompromised conditions (Non-HIV with IC Group, n = 11), and immunocompetent patients (n = 25).

Results

All the patients were diagnosed by pathogen culture or by metagenomic next-generation sequencing (mNGS). The median age was 50, and patients with HIV were much younger compared to the other two groups. The most common symptom at presentation was fever (79.6%), followed by cough (70.4%), weight loss (61.1%), and expectoration (53.7%). The patients with HIV were more likely to develop into a subtype of disseminated TM affecting multiple organs including lymph node, liver, skin, and spleen, thus, resulting in higher hospital mortality compared to the other two groups. Patients without HIV but with immunocompromised conditions presented similar hospital mortality rates compared to immunocompetent patients, while experiencing longer days of hospitalization to recover from the diseases. Additionally, in this study, the pathogen culture easily confirmed the patients with HIV. However, mNGS presented as a promising tool to confirm TM infection in those suspicious patients without HIV.

Conclusions

In summary, patients with HIV were more likely to develop into disseminated TM, resulting in higher mortality compared to those patients without HIV. Additionally, mNGS presented as an important supplementary tool to confirm TM infection in patients without HIV, particularly in those with immunocompromised diseases.

A Reliable Murine Model of Disseminated Infection Induced by Talaromyces Marneffei

Talaromycosis (penicilliosis) caused by Talaromyces marneffei is one of the most important opportunistic infection diseases in tropical countries of South and Southeast Asia. Most infections occurred in individuals with human immunodeficiency virus (HIV) and the primarily reason for the increase in the number of the cases is HIV pandemic. The pathogenesis of T. marneffei infection is unclear. There is still no ideal animal model for studying talaromycosis. In this study, we developed a stable, safe and maneuverable murine model that mimics human T. marneffei disseminated infection using T. marneffei yeast intraperitoneal injected to BALB/c nude mice. We successfully observed symptoms similar to those seen in clinical patients in this murine model, including skin lesions, hepatosplenomegaly, pulmonary infection and mesenteric lesions. We further studied the pathological changes of various tissues and organs in the infected animals to help better understand the severity of the infection. This model may provide a good tool for studying disseminated infection induced by T. marneffei.

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.

Localized Talaromyces marneffei infection presenting as a tonsillar mass mimicking malignancy

Talaromyces marneffei is an opportunistic fungal infection seen in immunocompromised patients including those with HIV/AIDS. It is usually seen in patients who live in or are from tropical Asia. In HIV patients, oropharyngeal and laryngeal lesions are usually part of disseminated infection. We describe a case of 63-year-old Vietnamese male with history of HIV/AIDS who presented with localized T. marneffei tonsillar infection without disseminated disease. Imaging studies showed a right tonsillar mass with right cervical lymphadenopathy which was initially thought to be malignancy. The patient underwent biopsy of the mass and histology showed noncaseating granulomas on hematoxylin and eosin stain as well as yeast on Grocott methenamine silver stain. Fungal culture of the biopsy specimen grew suede-like grayish-white colonies with diffuse underlying deep red color pigment which was identified as Talaromyces marneffei. The patient was treated with intravenous liposomal amphotericin B and achieved resolution of symptoms and tonsillar mass. In HIV/AIDS patients who are either from endemic regions or with history of travel to endemic areas particularly Southeast Asia and China, T. marneffei infection should be considered in differential diagnoses of a tonsillar mass.

The hidden pathogenic potential of environmental fungi

Invasive fungal infections are a growing threat to immunocompromised patients, highlighting the importance of monitoring fungal pathogens. Global warming (including climatic oscillations) may select for environmental species that have acquired thermotolerance, a key step toward pathogenesis to humans. Also, important virulence factors have developed in environmental fungi, because they are essential for yeast survival in the environment. Thus, fungi traditionally regarded as nonpathogenic to humans have virulence factors similar to those of their pathogenic relatives. Here, we highlight the emergence of saprophytic environmental fungi - including species of Cryptococcus, Aspergillus, Penicillium, Candida and Scedosporium - as new human pathogens. Emerging pathogens are, in some cases, resistant to the available antifungals, potentiating the threat of novel fungal diseases.

Talaromyces marneffei Genomic, Transcriptomic, Proteomic and Metabolomic Studies Reveal Mechanisms for Environmental Adaptations and Virulence

Talaromycesmarneffei is a thermally dimorphic fungus causing systemic infections in patients positive for HIV or other immunocompromised statuses. Analysis of its ~28.9 Mb draft genome and additional transcriptomic, proteomic and metabolomic studies revealed mechanisms for environmental adaptations and virulence. Meiotic genes and genes for pheromone receptors, enzymes which process pheromones, and proteins involved in pheromone response pathway are present, indicating its possibility as a heterothallic fungus. Among the 14 Mp1p homologs, only Mp1p is a virulence factor binding a variety of host proteins, fatty acids and lipids. There are 23 polyketide synthase genes, one for melanin and two for mitorubrinic acid/mitorubrinol biosynthesis, which are virulence factors. Another polyketide synthase is for biogenesis of the diffusible red pigment, which consists of amino acid conjugates of monascorubin and rubropunctatin. Novel microRNA-like RNAs (milRNAs) and processing proteins are present. The dicer protein, dcl-2, is required for biogenesis of two milRNAs, PM-milR-M1 and PM-milR-M2, which are more highly expressed in hyphal cells. Comparative transcriptomics showed that tandem repeat-containing genes were overexpressed in yeast phase, generating protein polymorphism among cells, evading host's immunity. Comparative proteomics between yeast and hyphal cells revealed that glyceraldehyde-3-phosphate dehydrogenase, up-regulated in hyphal cells, is an adhesion factor for conidial attachment.

Uncommon opportunistic fungal infections of oral cavity: A review

The majority of opportunistic oral mucosal fungal infections are due to Candida albicans and Aspergillus fumigatus species. Mucor and Cryptococcus also have a major role in causing oral infections, whereas Geotrichum, Fusarium, Rhodotorula, Saccharomyces and Penicillium marneffei are uncommon pathogens in the oral cavity. The broad spectrum of clinical presentation includes pseudo-membranes, abscesses, ulcers, pustules and extensive tissue necrosis involving bone. This review discusses various uncommon opportunistic fungal infections affecting the oral cavity including their morphology, clinical features and diagnostic methods.

Itraconazole (Sporanox®) in superficial and systemic fungal infections

Itraconazole (Sporanox) is a triazole antifungal agent with a broad activity spectrum and favorable pharmacokinetic and safety profiles. Numerous clinical trials have established the efficacy and safety of itraconazole in the treatment of superficial fungal infections. In this field, full exploitation of its pharmacokinetics in keratinized tissues has led to the development of intermittent (pulse) treatment regimens that allow similar efficacy with lower overall drug exposure as well as a reduction in treatment costs. The additional anti-inflammatory action of itraconazole also makes it suitable for application in difficult-to-treat inflammatory skin disorders, such as seborrheic dermatitis. Recently, a new oral liquid formulation and an intravenous formulation have been developed, extending the therapeutic application of itraconazole to systemic fungal infections. Due to its broad activity spectrum and excellent tolerability, itraconazole is a valuable addition to the antifungal armamentarium used for prophylactic and empiric treatment in immunocompromised hosts.

Penicillinosis in a HIV-positive individual

Penicillium marneffei is a dimorphic fungus, which can cause fatal infection in HIV-infected patients. The aim of this article is to report a rare case of penicillinosis in an HIV-positive patient from a nonendemic area such as Paonta Sahib, Himachal Pradesh. The patient presented with nonhealing painful ulcer on tongue, chest pain, cough, and chronic diarrhea. Diagnosis was made possible through blood investigations and culture reports of saliva and blood samples.

Oral ranula in an HIV-positive patient: case report and literature review

We describe the presentation and treatment of an HIV-positive patient with an oral ranula, and review the literature. Ranulas are mucoceles or retention cysts formed by the extravasation of mucus from the sublingual gland, presumably due to continued production of saliva in the presence of ductal obstruction. Oral ranulas in children are rare and the overall prevalence of mucoceles has been reported as 0.08% in children aged 0-12 years. However, there has been a documented increased occurrence in HIV-positive patients. This has been attributed to a blockage of the salivary gland by inflammation and peri-ductal fibrosis following HIV-associated salivary gland disease. Oral lesions may indicate infection with HIV and can also predict progression of HIV to AIDS. The most common oral manifestation is oral candidiasis occurring in 67% of children with HIV. Following this salivary gland disease, periodontal and gingival disease and herpes simplex are the next most common. The exact prevalence of ranulas in an HIV population is not known but the occurrence of a paediatric patient with HIV having at least one oral lesion has been documented as high as 63% and salivary gland disease at 50%. The true extent of the relationship between HIV and ranula is as yet unknown. This represents the only reported case of oral ranula in an HIV-positive patient in the UK.

An audit of ranulae occurring with the human immunodeficiency virus infecton

Currently, published literature has increasingly projected the ranula as a lesion that may be closely associated with exposure to the human immunodeficiency virus (HIV). In this report, we document 28 patients who presented with ranulae, among whom 19 were HIV infected. In some, this was the only lesion that was the sentinel sign of HIV infection. Most probably, this lesion could be considered as one of the clinical markers of this infection.

Endemic fungal infections in the Asia-Pacific region

Endemic mycoses are important fungal infections in their respective habitats. In the Asia-Pacific region, an accurate epidemiological picture of endemic mycoses is elusive; few epidemiological surveys have been performed, and limited laboratory facilities and experience with fungal infections have further hampered recognition of infection. However, pockets of endemicity do indeed exist, and endemic fungal infections can have a significant impact on public health. This article reviews the most common endemic mycoses in the Asia-Pacific region: histoplasmosis, penicilliosis, and sporotrichosis. Blastomycosis, which has been infrequently reported within the region, is also briefly discussed. Certain areas of the Asia-Pacific region are endemic for histoplasmosis; however, the ecologic niche for this infection remains unclear. Penicilliosis is restricted to Southeast and Eastern Asia, whereas sporotrichosis is encountered in tropical areas of the Asia-Pacific region linked to environmental reservoirs distinct from those seen in the Western world. Before the advent of acquired immune deficiency syndrome (AIDS), histoplasmosis and penicilliosis were only occasionally reported; however, the incidence of both mycoses has increased with the rise in the incidence of AIDS. Comprehensive studies are needed to fully assess the areas of endemicity and the impact of endemic mycoses in the Asia-Pacific region.

Ranula: another HIV/AIDS associated oral lesion in Zimbabwe?

AIM

To show that sublingual ranula is associated with HIV/AIDS and as such should be considered an HIV/AIDS associated oral lesion in Zimbabwe.

OBJECTIVES

To retrospectively study the prevalence, age and gender distribution, the HIV serostatus of ranula patients and the trend in prevalence of ranula and Kaposi's sarcoma (KS) in patients at the two largest referral Oral and Maxillofacial Surgery specialist centres in Harare, Zimbabwe. To use this information to infer an association between ranula and HIV/AIDS in Zimbabwe.

DESIGN

Descriptive study with a retrospective and prospective component.

SETTING

Oral and Maxillofacial Surgical clinics at specialist referral hospitals, Harare Central Hospital and Parirenyatwa Government Hospital, Harare, Zimbabwe.

SUBJECTS

Eighty-three cases of ranula were studied: 45 cases retrospectively and 38 consecutively. A total of 231 cases of KS were studied retrospectively.

METHODS

Histopathologic records of patients who presented with ranula and KS during the period January 1981 to September 2003 were studied. Gender and age were recorded for each case. Thirty-eight ranula patients studied consecutively during the period June 1999 to September 2003 were consented for HIV testing.

RESULTS

There were 83 cases of ranula; 43.4% male and 56.6% female. There were 231 cases of KS, 61.2% male and 38.8% female. Male to female ratio was 1:1.3 for ranula and for KS was 1:0.6. Ranula was predominant in the 0-10 year age group (73.5%) while KS was most common in the 21-40 year age group (76.4%). Ranula and KS both had a marked rise in prevalence from 1992 to 2003. A total of 88.5% of the ranula cases tested HIV positive with 95% in the 0-10 year age group.

CONCLUSION

There was a rising prevalence of ranula which mirrors that of KS (an HIV/AIDS associated oral lesion) and that 88.5% of ranula patients were HIV positive with 95% of them in the 0-10 year age group. Sublingual ranula should thus be considered another HIV/AIDS associated lesion in Zimbabwe, especially in children.

Prevalence and classification of HIV-associated oral lesions

OBJECTIVES

An International Workshop addressed the prevalence and classification of HIV/ AIDS associated oral lesions.

DESIGN

Five questions provided the framework for discussion and literature review. What is the prevalence of oral lesions in children and adults? Should the accepted classification of HIV-related oral lesions be modified in the light of recent findings? Why is there a gender difference in the prevalence of oral lesions in developed and developing countries? Are there unusual lesions present in developing countries? Is there any association between modes of transmission and the prevalence of oral lesions?

RESULTS

Workshop discussion emphasized the urgent need for assistance in the development of expertise to obtain accurate global prevalence data for HIV-associated oral lesions. Oral candidiasis has been consistently reported as the most prevalent HIV-associated oral lesion in all ages. Penicilliosis marneffei, a newly described fungal infection, has emerged in South-east Asia. Oral hairy leukoplakia and Kaposi's sarcoma appear to be associated with male gender and male-to-male HIV transmission risk behaviours. These lesions occur only rarely in children.

CONCLUSIONS

Additional prevalence data are needed from developing countries prior to substantially altering the 1993 ECC/WHO Classification of oral lesions associated with adult HIV infection. The workshop confirmed current oral disease diagnostic criteria.

Case Report. Oro-facial manifestations of Penicillium marneffei infection in a Thai patient with AIDS

Penicillium marneffei infection is prevalent in South-East Asia and Southern China and has been considered an acquired immunodeficiency syndrome (AIDS)-defining disease. This report focuses on the oral and facial manifestations of P. marneffei infection in a 28-year-old Thai male patient with AIDS. The clinical, mycological and ultrastructural features are described.