Penicillium marneffei infection in HIV

Endemic Systemic Mycoses in Italy: A Systematic Review of Literature and a Practical Update

Endemic systemic mycoses such as blastomycosis, coccidioidomycosis, histoplasmosis, talaromycosis, paracoccidioidomycosis are emerging as an important cause of morbidity and mortality worldwide. We conducted a systematic review on endemic systemic mycoses reported in Italy from 1914 to nowadays. We found out: 105 cases of histoplasmosis, 15 of paracoccidioidomycosis, 10 of coccidioidomycosis, 10 of blastomycosis and 3 of talaromycosis. Most cases have been reported in returning travelers and expatriates or immigrants. Thirtytwo patients did not have a story of traveling to an endemic area. Fortysix subjects had HIV/AIDS. Immunosuppression was the major risk factor for getting these infections and for severe outcomes. We provided an overview on microbiological characteristics and clinical management principles of systemic endemic mycoses with a focus on the cases reported in Italy.

Exosomes released from macrophages infected with Talaromyces marneffei activate the innate immune responses and decrease the replication

INTRODUCTION

Recent studies have demonstrated that exosomes play roles in pathogenesis and in the treatment of various diseases. We explored the influence of exosomes released from Talaromyces marneffei (T. marneffei)-infected macrophages on human macrophages to determine whether they play a role in the pathogenesis of T. marneffei infection.

METHODS

Exosomes derived from macrophages infected with T. marneffei were extracted and characterized by transmission electron microscopy and western blot. Moreover, we examined exosomes that modulated IL-10 and TNF-α secretion and activation of p42 and p44 extracellular signal-regulated kinase 1 and 2 (ERK1/2) and activation of autophagy.

RESULTS

We found that exosomes promoted activation of ERK1/2 and autophagy, IL-10 and TNF-α secretion in human macrophages. Further, exosomes decreased the multiplication of T. marneffei in T. marneffei-infected human macrophages. Interestingly, exosomes isolated from T. marneffei-infected but not from uninfected macrophages can stimulate innate immune responses in resting macrophages.

CONCLUSION

Our studies are the first to demonstrate that exosomes isolated from T. marneffei-infected macrophages can modulate the immune system to control inflammation, and we hypothesize that exosomes play significant roles in activation of ERK1/2 and autophagy, the replication of T. marneffei and cytokine production during T. marneffei infection.

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.

HIV-child with disseminated Talaromyces Marneffei (Penicillium marneffei) infection: a rare severe case report

Background

Talaromyces Marneffei (Penicillium marneffei, T.marneffei) has been frequently reported in patients with adult acquired immunodeficiency syndrome. Still, cases of children with HIV combined with T.marneffei infection are very rare. This report describes the case of a HIV-child who is a girl from China. Her special clinical manifestations and laboratory diagnosis results can provide clinicians with the basis for diagnosis and treatment of T.marneffei related rare diseases.

Case presntation

We reported a single case of 7-year-old Chinese female patient who presented with fever, abdominal pain, multiple lymphadenopathy, hepatosplenomegaly, left lower extremity ecchymosis, and bloody stool. The patient received anti-inflammatory therapy; however, her symptoms did not improve. Consequently, she was diagnosed with T.marneffei and HIV infection; it was also confirmed that her mother did not undergo HIV blocking therapy during pregnancy. Yet, the child’s family refused all treatment, after which the child was discharged from the hospital. The patient died a few days later.

Conclusion

This case suggested that children with AIDS suffering from fever, lymphadenopathy and coagulation dysfunction, penicilliosis should be suspected. Clinicians should diagnose the disease early through laboratory and imaging results, which can help reduce the mortality, prolong the survival time and improve the quality of life of children.

Violet colonies of Talaromyces marneffei produce on CHROMagar candida medium

In the present report, we describe an unusual case of mixed infection of Candida albicans and Talaromyces marneffei in the oral cavity and oropharynx with cutaneous involvement. On the CHROMagar Candida plate, green colonies (identified as C. albicans) and tiny violet colonies (identified as T. marneffei) grew from the throat swab after incubation for 96 hours. 10 clinical isolates of T. marneffei were used to verify their color production on CHROMagar Candida. All colonies were violet on the fourth, seventh and ninth day incubated at 37 °C. T. marneffei appears violet on the CHROMagar Candida plate, but it may be easily ignored because of its slow growth and small colony size, especially after incubation for 48 hours. Therefore, when using CHROMagar Candida plate to detect specimens in AIDS patients, special attention must be paid to detect non-yeasts such as T. marneffei for up to 96 hours.

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.

Anti-interferon-γ autoantibody-associated immunodeficiency

Anticytokine autoantibodies are an emerging disease etiology, through the disturbance of physiological functions of cognate cytokines. Anti-interferon (IFN)-γ autoantibodies (AIGAs) were first identified in patients with severe mycobacterial infections, and were considered to be an autoimmune phenocopy of inborn genetic errors of the IL-12/IFN-γ axis. More than 600 reported cases, most originating from Southeast Asia, have been diagnosed over the last decade. Specific HLA class II molecules are associated with these autoantibodies, which provide a genetic basis for the high prevalence of this immunodeficiency syndrome in certain ethnic groups. Salmonellosis and herpes zoster reactivation are observed in more than half the patients with AIGAs. Moreover, AIGAs have been shown to underlie severe Taralomyce marneffei infection in HIV-negative patients. AIGAs may, thus, be considered a new form of late-onset immunodeficiency conferring a predisposition not only to severe mycobacterial, but also to some bacterial and fungal infections.

The Association of TLR2, TLR3, and TLR9 Gene Polymorphisms With Susceptibility to Talaromycosis Among Han Chinese AIDS Patients in Guangdong

Background

Talaromycosis (TM) caused by Talaromyces marneffei (T. marneffei) is a growing public health concern. Although Toll-like receptor (TLR) genes play a critical role in the host defense against fungal infection, the influence of polymorphisms in these genes on the susceptibility of acquired immune deficiency syndrome (AIDS) patients to TM remains unknown. This study aims to uncover the associations of single nucleotide polymorphisms (SNPs) in TLR genes with TM susceptibility among patients with AIDS.

Methods

Altogether 200 AIDS patients complicated with TM, 200 matched AIDS patients without TM, and 76 healthy controls (HCs) were enrolled in this case-control study. In total, 23 SNPs in the TLR2, TLR4, and TLR9 genes, which may influence the susceptibility of AIDS patients to TM, were checked by the time of flight mass spectrometry (TOF/MS) method among these Han Chinese subjects.

Results

No significant differences in genotype or allele frequencies of selected SNPs were found among the TM group, Non-TM group, and HC group. Haplotype analysis also demonstrated no correlation of these SNPs with TM. However, subgroup analysis showed that the genotype TT and the T allele in TLR2 SNP rs1339 were more frequent in typical TM cases than controls (50.0 vs. 35.8%, 70.5 vs. 59.7%); the frequency of the GT genotype in TLR2 SNP rs7656411 was markedly higher in severe TM cases compared to controls (57.8 vs. 34.4%).

Conclusion

Our results demonstrate a genetic connection of TLR2 SNPs rs1339 and rs7656411 with an increased susceptibility and severity of TM among Han Chinese populations.

Characterization of Clinical Isolates of Talaromyces marneffei and Related Species, California, USA

Talaromyces marneffei and other Talaromyces species can cause opportunistic invasive fungal infections. We characterized clinical Talaromyces isolates from patients in California, USA, a non-Talaromyces-endemic area, by a multiphasic approach, including multigene phylogeny, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and phenotypic methods. We identified 10 potentially pathogenic Talaromyces isolates, 2 T. marneffei.

A unique aspartyl protease gene expansion in Talaromyces marneffei plays a role in growth inside host phagocytes

Aspartyl proteases are a widely represented class of proteolytic enzymes found in eukaryotes and retroviruses. They have been associated with pathogenicity in a range of disease-causing microorganisms. The dimorphic human-pathogenic fungus Talaromyces marneffei has a large expansion of these proteases identified through genomic analyses. Here we characterize the expansion of these genes (pop - paralogue of pep) and their role in T. marneffei using computational and molecular approaches. Many of the genes in this monophyletic family show copy number variation and positive selection despite the preservation of functional regions and possible redundancy. We show that the expression profile of these genes differs and some are expressed during intracellular growth in the host. Several of these proteins have distinctive localization as well as both additive and epistatic effects on the formation of yeast cells during macrophage infections. The data suggest that this is a recently evolved aspartyl protease gene family which affects intracellular growth and contributes to the pathogenicity of T. marneffei.

Activation of autophagy and IL-10 production are regulated by Jun N-terminal kinase 1 and 2 and p38 mitogen activated protein kinase signaling pathways during Talaromyces marneffei infection within dendritic cells

Previous study have shown that Talaromyces marneffei (T. marneffei) induced activation of autophagy. Therefore, we explore signaling pathway that regulates activation of autophagy by intracellular signaling mechanisms during T. marneffei infection. Further, we examine c-Jun N-terminal kinase 1 and 2 (JNK1/2) and p38 signaling pathways that regulate IL-1β and IL-10 production and activation of autophagy during T. marneffei infection in human dendritic cells (DCs). We found that T. marneffei induced activation of JNK1/2 and p38 in human DCs. Furthermore, the inhibition of JNK1/2 and p38 increased activation of autophagy and decreased the replication of T. marneffei in T. marneffei-infected human DCs. Moreover, IL-1β secretion in T. marneffei-infected human DCs was dependent on JNK1/2 and autophagy pathways, whereas IL-10 secretion was dependent on JNK1/2, p38 and autophagy pathways. These data suggest that JNK1/2 and p38 pathways play critical roles in activation of autophagy, the multiplication of T. marneffei and subsequent cytokine production during T. marneffei infection.

Concurrent infection with Talaromyces marneffei and Cryptococcus neoformans in a patient without HIV infection

A case report of coinfection with Talaromyces marneffei (T. marneffei) and Cryptococcus neoformans (C. neoformans) is presented in a 57-year-old woman with hemolytic anemia who received dexamethasone for 8 years. To the best of our knowledge, this patient was successfully treated with voriconazole. This is the first case of T. marneffei and C. neoformans coinfection in a HIV-negative host. Clinicians should be aware of concomitant infection with T. marneffei and other pathogens in immunocompromised hosts. The current case report highlights the importance of clinician awareness of concurrent infections with T. marneffei and other pathogens in immunosuppressed patients.

Talaromyces marneffei Mp1 Protein, a Novel Virulence Factor, Carries Two Arachidonic Acid-Binding Domains To Suppress Inflammatory Responses in Hosts

Talaromyces marneffei infection causes talaromycosis (previously known as penicilliosis), a very important opportunistic systematic mycosis in immunocompromised patients. Different virulence mechanisms in T. marneffei have been proposed and investigated. In the sera of patients with talaromycosis, Mp1 protein (Mp1p), a secretory galactomannoprotein antigen with two tandem ligand-binding domains (Mp1p-LBD1 and Mp1p-LBD2), was found to be abundant. Mp1p-LBD2 was reported to possess a hydrophobic cavity to bind copurified palmitic acid (PLM). It was hypothesized that capturing of lipids from human hosts by expressing a large quantity of Mp1p is a virulence mechanism of T. marneffei It was shown that expression of Mp1p enhanced the intracellular survival of T. marneffei by suppressing proinflammatory responses. Mechanistic study of Mp1p-LBD2 suggested that arachidonic acid (AA), a precursor of paracrine signaling molecules for regulation of inflammatory responses, is the major physiological target of Mp1p-LBD2. In this study, we use crystallographic and biochemical techniques to further demonstrate that Mp1p-LBD1, the previously unsolved first lipid binding domain of Mp1p, is also a strong AA-binding domain in Mp1p. These studies on Mp1p-LBD1 support the idea that the highly expressed Mp1p is an effective AA-capturing protein. Each Mp1p can bind up to 4 AA molecules. The crystal structure of Mp1p-LBD1-LBD2 has also been solved, showing that both LBDs are likely to function independently with a flexible linker between them. T. marneffei and potentially other pathogens highly expressing and secreting proteins similar to Mp1p can severely disturb host signaling cascades during proinflammatory responses by reducing the availabilities of important paracrine signaling molecules.

Rare fungal infectious agents: a lurking enemy

In the expanding population of immunocompromised patients and those treated in intensive care units, rare fungal infectious agents have emerged as important pathogens, causing invasive infections associated with high morbidity and mortality. These infections may present either as de novo or as breakthrough invasive infections in high-risk patients with hematologic malignancies receiving prophylactic or empirical antifungal therapy or in patients with central venous catheters. Diagnosis and treatment are challenging. Physicians should have a high index of suspicion because early diagnosis is of paramount importance. Conventional diagnostic methods such as cultures and histopathology are still essential, but rapid and more specific molecular techniques for both detection and identification of the infecting pathogens are being developed and hopefully will lead to early targeted treatment. The management of invasive fungal infections is multimodal. Reversal of risk factors, if feasible, should be attempted. Surgical debridement is recommended in localized mold infections. The efficacy of various antifungal drugs is not uniform. Amphotericin B is active against most yeasts, except Trichosporon, as well as against Mucorales, Fusarium, and some species of Paecilomyces and dimorphic fungi. The use of voriconazole is suggested for the treatment of trichosporonosis and scedosporiosis. Combination treatment, though recommended as salvage therapy in some infections, is controversial in most cases. Despite the use of available antifungals, mortality remains high. The optimization of molecular-based techniques, with expansion of reference libraries and the possibility for direct detection of resistance mechanisms, is awaited with great interest in the near future. Further research is necessary, however, in order to find the best ways to confront and destroy these lurking enemies.

Clinical Characteristics and Prognosis of Penicilliosis Among Human Immunodeficiency Virus-Infected Patients in Eastern China

AbstractTalaromyces marneffei infection is increasingly observed in people living with human immunodeficiency virus (HIV) in eastern China, a nonendemic area. This study aimed to draw the clinician's attention to this disease by presenting the clinical characteristics and prognosis of penicilliosis among HIV-infected patients from this region. We retrospectively analyzed HIV-infected patients with culture-proven T. marneffei infection admitted during January 1, 2014-December 31, 2015, at the Shanghai Public Health Clinical Center. A total of 48 patients with confirmed HIV infection and penicilliosis were enrolled, which accounted for a mean of 3.2% (95% confidence interval: 2.4-4.2%) of yearly HIV infection admissions among patients from eastern China. Symptoms included fever, cough, and gastrointestinal complaints, whereas the most common sign was skin lesions. Anemia occurred in 87.5% (42/48) of the patients. The overall mortality rate was 16.7%. Low CD4 T-cell count and hemoglobin level were correlated with mortality. Based on these results, we concluded that penicilliosis should be considered in HIV-infected patients from eastern China who present with fever, cutaneous lesions, and anemia. The clinical characters and the prognosis of patients with penicilliosis are similar to those in endemic areas. More attention should be paid to penicilliosis patients with low CD4 T-cell count and/or low hemoglobin level.

Adaptation to macrophage killing by Talaromyces marneffei

Talaromyces (Penicillium) marneffei is an important opportunistic fungal pathogen. It causes disseminated infection in immunocompromised patients especially in Southeast Asian countries. The pathogenicity of T. marneffei depends on the ability of the fungus to survive the killing process and replicate inside the macrophage. Major stresses inside the phagosome of macrophages are heat, oxidative substances and nutrient deprivation. The coping strategies of this pathogen with these stresses are under investigation. This paper summarizes factors relating to the stress responses that contribute to the intracellular survival of T. marneffei. These include molecules in the MAP signal transduction cascade, heat shock proteins, antioxidant enzymes and enzymes responsible in nutrient retrieval. There is speculation that the ability of T. marneffei to withstand these defenses plays an important role in its pathogenicity.

Talaromyces marneffei is an important dimorphic fungus that causes disease in immunocompromised patients. The pathogenicity of T. marneffei depends on the ability of the fungus to survive the killing process and replicate inside the host macrophage cells. This paper summarizes factors relating to the stress responses that contribute to the intracellular survival of T. marneffei. There is speculation that the ability of T. marneffei to withstand these defenses plays an important role in its pathogenicity.

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.

Talaromyces marneffei Mp1p Is a Virulence Factor that Binds and Sequesters a Key Proinflammatory Lipid to Dampen Host Innate Immune Response

Talaromyces (Penicillium) marneffei is one of the leading causes of systemic mycosis in immunosuppressed or AIDS patients in Southeast Asia. How this intracellular pathogen evades the host immune defense remains unclear. We provide evidence that T. marneffei depletes levels of a key proinflammatory lipid mediator arachidonic acid (AA) to evade the host innate immune defense. Mechanistically, an abundant secretory mannoprotein Mp1p, shown previously to be a virulence factor, does so by binding AA with high affinity via a long hydrophobic central cavity found in the LBD2 domain. This sequesters a critical proinflammatory signaling lipid, and we see evidence that AA, AA's downstream metabolites, and the cytokines interleukin-6 and tumor necrosis factor α are downregulated in T. marneffei-infected J774 macrophages. Given that Mp1p-LBD2 homologs are identified in other fungal pathogens, we expect that this novel class of fatty-acid-binding proteins sequestering key proinflammatory lipid mediators represents a general virulence mechanism of pathogenic fungi.

Organism-wide studies into pathogenicity and morphogenesis in Talaromyces marneffei

Organism-wide approaches examining the genetic mechanisms controlling growth and proliferation have proven to be a powerful tool in the study of pathogenic fungi. For many fungal pathogens techniques to study transcription and protein expression are particularly useful, and offer insights into infection processes by these species. Here we discuss the use of approaches such as differential display, suppression subtractive hybridization, microarray, RNA-seq, proteomics, genetic manipulation and infection models for the AIDS-defining pathogen Talaromyces marneffei. Together these methods have broadened our understanding of the biological processes, and genes that underlie them, which are involved in switching between the saprophytic and pathogenic states of T. marneffei, the maintenance of these two specialized cell types and its ability to cause disease.

Activation of ERK1/2 and TNF-α production are regulated by calcium/calmodulin signaling pathway during Penicillium marneffei infection within human macrophages

Previous study have shown that Penicillium marneffei (P. marneffei)-induced TNF-α production via an extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase-dependent mechanism is an important host defence mechanism against P. marneffei in human macrophages. Therefore, we explore signaling pathway that regulates TNF-α secretion and activation of ERK1/2 by intracellular signaling mechanisms during P. marneffei infection. We found that ERK1/2 activation was dependent on the calcium/calmodulin/calmodulin kinase Ⅱ pathway in P. marneffei-infected human macrophages. In contrast, P. marneffei-induced p38 MAPK activation was negatively regulated by calcium/calmodulin/calmodulin kinase Ⅱ signaling pathway. Furthermore, TNF-α production in P. marneffei-infected human macrophages was also dependent on Ca(2+)/calmodulin/calmodulin kinase Ⅱ pathway. These data suggest that Ca(2+)/calmodulin/calmodulin kinase Ⅱ pathway plays vital regulatory roles in macrophage activation and subsequent cytokine production during P. marneffei infection.

Imaging characteristics of disseminated Geosmithia argillacea causing severe diskospondylitis and meningoencephalomyelitis in a dog

A 4-year-old male castrated Labrador Retriever presented for severe spinal pain. Radiographs and magnetic resonance imaging showed evidence of diskospondylitis and meningoencephalomyelitis. Blood culture revealed a Geosmithia argillacea fungal infection after DNA sequencing, initially misdiagnosed as Penicillium species. Geosmithia argillacea should be considered as a differential for disseminated fungal diskospondylitis.

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.

Role of intracellular free calcium in killing Penicillium marneffei within human macrophages

Increases in cytosolic Ca(2+) concentration ([Ca(2+)]c) promote phagocyte antimicrobial responses. Here, we investigated macrophages stimulated by Penicillium marneffei (P. marneffei). [Ca(2+)]c was determined in macrophages loaded with the fluorescent calcium probe Fura 2/AM as they were stimulated by P. marneffei. We found that P. marneffei induced an increase in [Ca(2+)]c in human macrophages. Further, increased [Ca(2+)]c with the ionophore A23187 promoted phagosomal acidification and maturation and reduced intracellular replication of P. marneffei in P. marneffei-infected human macrophages, whereas decreased [Ca(2+)]c with the chelation MAPTAM decreased TNF-α production, inhibited phagosomal acidification and maturation and increased intracellular replication of P. marneffei. These data indicate that Ca(2+) signaling may play an important role in controlling the replication of P. marneffei within macrophages.

Effect of Jun N-terminal kinase 1 and 2 on the replication of Penicillium marneffei in human macrophages

Penicillium marneffei (P. marneffei) is a human pathogen which persists in macrophages and threatens the immunocompromised patients. To clarify the mechanisms involved, we evaluated the effect of c-Jun N-terminal kinase 1 and 2 (JNK1/2) on cytokine expression, phagosomal maturation and multiplication of P. marneffei in P. marneffei-stimulated human macrophages. P. marneffei induced the rapid phosphorylation of JNK1/2. Using the specific inhibitor of JNK1/2 (SP600125), we found that the inhibition of JNK1/2 suppressed P. marneffei-induced tumor necrosis factor-α and IL-10 production. In addition, the presence of SP600125 increased phagosomal acidification and maturation and decreased intracellular replication. These data suggest that JNK1/2 may play an important role in promoting the replication of P. marneffei. Our findings further indicate that the pathogen through the JNK1/2 pathway may attenuate the immune response and macrophage antifungal function.

Chitin recognition via chitotriosidase promotes pathologic type-2 helper T cell responses to cryptococcal infection

Pulmonary mycoses are often associated with type-2 helper T (Th2) cell responses. However, mechanisms of Th2 cell accumulation are multifactorial and incompletely known. To investigate Th2 cell responses to pulmonary fungal infection, we developed a peptide-MHCII tetramer to track antigen-specific CD4+ T cells produced in response to infection with the fungal pathogen Cryptococcus neoformans. We noted massive accruement of pathologic cryptococcal antigen-specific Th2 cells in the lungs following infection that was coordinated by lung-resident CD11b+ IRF4-dependent conventional dendritic cells. Other researchers have demonstrated that this dendritic cell subset is also capable of priming protective Th17 cell responses to another pulmonary fungal infection, Aspergillus fumigatus. Thus, higher order detection of specific features of fungal infection by these dendritic cells must direct Th2 cell lineage commitment. Since chitin-containing parasites commonly elicit Th2 responses, we hypothesized that recognition of fungal chitin is an important determinant of Th2 cell-mediated mycosis. Using C. neoformans mutants or purified chitin, we found that chitin abundance impacted Th2 cell accumulation and disease. Importantly, we determined Th2 cell induction depended on cleavage of chitin via the mammalian chitinase, chitotriosidase, an enzyme that was also prevalent in humans experiencing overt cryptococcosis. The data presented herein offers a new perspective on fungal disease susceptibility, whereby chitin recognition via chitotriosidase leads to the initiation of harmful Th2 cell differentiation by CD11b+ conventional dendritic cells in response to pulmonary fungal infection.

Humans often inhale potentially pathogenic fungi in the environment. While CD4+ helper T (Th) cells are required for protection against invasive disease, a subset of Th cells, called Th2 cells, are associated with increased mortality and allergy/asthma morbidity. Our study aimed to unravel the cellular and molecular basis of pulmonary Th2 cell induction in response to lethal infection with Cryptococcus neoformans. Antigen-presenting cells coordinate naïve Th cell priming and differentiation, but the precise leukocyte responsible for Th2 cell expansion to pulmonary cryptococcal infection has not been determined. Using an experimental mouse model of pulmonary cryptococcosis, we show that a subset of lung-resident dendritic cells is uniquely required for Th2 cell induction. We additionally sought to identify the molecular signal received by the host that allows dendritic cells to selectively induce Th2 cells. Since parasites and fungi elicit Th2 cell responses and both produce chitin, a molecule not found in vertebrates, we hypothesized that recognition of fungal chitin is a determinant of fungal disease. Here, we demonstrate that C. neoformans chitin and the host-derived chitinase, chitotriosidase, promote Th2 cell accumulation and disease. These findings highlight a promising target of next generation therapies aimed at limiting immunopathology caused by pulmonary fungal infection.

Thermally Dimorphic Human Fungal Pathogens--Polyphyletic Pathogens with a Convergent Pathogenicity Trait

Fungi are adept at changing their cell shape and developmental program in response to signals in their surroundings. Here we focus on a group of evolutionarily related fungal pathogens of humans known as the thermally dimorphic fungi. These organisms grow in a hyphal form in the environment but shift their morphology drastically within a mammalian host. Temperature is one of the main host signals that initiates their conversion to the "host" form and is sufficient in the laboratory to trigger establishment of this host-adapted developmental program. Here we discuss the major human pathogens in this group, which are Blastomyces dermatiditis, Coccidioides immitis/posadasii, Histoplasma capsulatum, Paracoccidioides brasiliensis/lutzii, Sporothrix schenckii, and Talaromyces marneffei (formerly known as Penicillium marneffei). The majority of these organisms are primary pathogens, with the ability to cause disease in healthy humans who encounter them in endemic areas.

Brain magnetic resonance imaging screening is not useful for HIV-1-infected patients without neurological symptoms

We investigated the diagnostic usefulness of brain magnetic resonance imaging (MRI) screening in HIV-1-infected patients without neurological symptoms in detecting intracranial diseases at early stages. In this retrospective analysis, the study patients were HIV-1-infected patients who underwent brain MRI scan in clinical practice between 2001 and 2013. We excluded patients with MRI for (1) follow-up examination for prediagnosed intracranial diseases, (2) cancer staging, (3) screening mycobacterium/bacteria/fungi disease proliferation in the brain, and (4) evaluation for meningitis/encephalitis. The study patients (n=485) were classified into two groups: those who underwent brain MRI scan without any neurological symptoms/signs (asymptomatic patients, n=158) and those who underwent MRI due to such symptoms (symptomatic patients, n=327). Asymptomatic patients had lower CD4 counts than symptomatic patients (median 78 versus 241/μl). Intracranial diseases were detected in three (2%) of the asymptomatic patients [two toxoplasmosis and one progressive multifocal leukoencephalopathy (PML)] compared to 58 (19%) of the symptomatic patients (the χ(2) test, p<0.01). The latter included toxoplasmosis (n=10), PML (n=7), cytomegalovirus encephalitis (n=3), primary central nervous system lymphoma (n=3), cryptococcoma/meningitis (n=3), and HIV-associated dementia (n=17). Among symptomatic patients, intracranial diseases were common in those with slurred speech (3/6, 50%), seizure (4/10, 40%), eyesight/vision abnormality (5/16, 31%), altered mental status (8/31, 26%), and hemiplegia/numbness (13/50, 26%). For patients with CD4 count <200/μl, intracranial diseases were detected in only 3 (3%) of 144 asymptomatic patients, compared with 46 (32%) of 113 symptomatic patients (p<0.01). Brain MRI screening for HIV-1-infected patients without neurological symptoms is of little value.

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.

Detection of DOPA-melanin in the dimorphic fungal pathogen Penicillium marneffei and its effect on macrophage phagocytosis in vitro

The fungal pathogen Penicillium marneffei produces melanin-like pigment in vitro. The synthetic pathway of melanin and its possible influence in the protective yeast cells surviving within macrophage cells are not known. In this work, P. marneffei produced brown black pigment in the presence of L-DOPA and black particles were extracted from yeast cells treated with proteolytic enzymes, denaturant and concentrated hot acid. Kojic acid inhibited the brown-black pigment production of P. marneffei yeast grown on brain heart infusion agar. Transmitting electron microscopy showed spherical granular electron-dense particles with an average diameter of 100 nm in a beaded arrangement in the innermost cell wall. Electron-paramagnetic resonance revealed that the black particles contain a stable free radical compound. The UV-visible and Fourier transform infrared spectra of particles extracted from P. marneffei and synthetic DOPA-melanin showed a high degree of similarity. Melanized yeast cells decreased phagocytosis by macrophage cells and increased resistance to intracellular digestion in vitro. These results indicate that P. marneffei can synthesize DOPA-melanin or melanin-like compounds in vitro and suggest that the DOPA-melanin pathway is associated with cell wall structure and enhances the resistance to phagocytosis by macrophages.

A neglected epidemic: fungal infections in HIV/AIDS

Invasive fungal infections (IFIs) are a major cause of HIV-related mortality globally. Despite widespread rollout of combined antiretroviral therapy, there are still up to 1 million deaths annually from IFIs, accounting for 50% of all AIDS-related death. A historic failure to focus efforts on the IFIs that kill so many HIV patients has led to fundamental flaws in the management of advanced HIV infection. This review, based on the EMBO AIDS-Related Mycoses Workshop in Cape Town in July 2013, summarizes the current state of the-art in AIDS-related mycoses, and the key action points required to improve outcomes from these devastating infections.

Unraveling the molecular basis of temperature-dependent genetic regulation in Penicillium marneffei

Penicillium marneffei is an opportunistic fungal pathogen endemic in Southeast Asia, causing lethal systemic infections in immunocompromised patients. P. marneffei grows in a mycelial form at the ambient temperature of 25°C and transitions to a yeast form at 37°C. The ability to alternate between the mycelial and yeast forms at different temperatures, namely, thermal dimorphism, has long been considered critical for the pathogenicity of P. marneffei, yet the underlying genetic mechanisms remain elusive. Here we employed high-throughput sequencing to unravel global transcriptional profiles of P. marneffei PM1 grown at 25 and 37°C. Among ∼11,000 protein-coding genes, 1,447 were overexpressed and 1,414 were underexpressed at 37°C. Counterintuitively, heat-responsive genes, predicted in P. marneffei through sequence comparison, did not tend to be overexpressed at 37°C. These results suggest that P. marneffei may take a distinct strategy of genetic regulation at the elevated temperature; the current knowledge concerning fungal heat response, based on studies of model fungal organisms, may not be applicable to P. marneffei. Our results further showed that the tandem repeat sequences (TRSs) are overrepresented in coding regions of P. marneffei genes, and TRS-containing genes tend to be overexpressed at 37°C. Furthermore, genomic sequences and expression data were integrated to characterize gene clusters, multigene families, and species-specific genes of P. marneffei. In sum, we present an integrated analysis and a comprehensive resource toward a better understanding of temperature-dependent genetic regulation in P. marneffei.

Penicillium marneffei presenting as an immune reconstitution inflammatory syndrome (IRIS) in a patient with advanced HIV

A 62-year-old British man with advanced HIV was established on antiretroviral therapy and treatment for disseminated Mycobacterium avium complex and Cytomegalovirus infections. One month later he re-presented with epigastric pain, an epigastric mass and skin lesions. Abdominal imaging revealed large volume lymphadenopathy, which was not present on previous imaging. Blood cultures yielded Penicillium marneffei, a dimorphic fungus endemic to South-east Asia. The patient had spent several years travelling in Thailand prior to the diagnosis of HIV. Penicilliosis is a common AIDS-defining illness in endemic areas, but remains rare in Europe. In this case, it presented in the context of a rapidly decreasing viral load as an immune reconstitution inflammatory syndrome. The challenges of management in the context of multiple comorbidities and polypharmacy are discussed.

Penicillium marneffei chylous ascites in acquired immune deficiency syndrome: A case report

Penicillium marneffei (P. marneffei) infection usually occurs with skin, bone marrow, lung or hepatic involvement. However, no cases of P. marneffei infection with chylous ascites have been reported thus far. In this report, we describe the first case of acquired immune deficiency syndrome (AIDS) which has been complicated by a P. marneffei infection causing chylous ascites. We describe the details of the case, with an emphasis on treatment regimen. This patient was treated with amphotericin B for 3 mo, while receiving concomitant therapy with an efavirenz-containing antiretroviral regimen, but cultures in ascitic fluid were persistently positive for P. marneffei. The infection resolved after treatment with high-dose voriconazole (400 mg every 12 h) for 3 mo. P. marneffei should be considered in the differential diagnosis of chylous ascites in human immunodeficiency virus patients. High-dose voriconazole is an effective, well-tolerated and convenient option for the treatment of systemic infections with P. marneffei in AIDS patients on an efavirenz-containing antiretroviral regimen.

Penicillium marneffei infection: an emerging disease in mainland China

Penicillium marneffei is an emerging pathogenic fungus that can cause a life-threatening systemic mycosis in immunocompromised hosts, especially in patients with AIDS. This infection is endemic in Southeast Asia. With the prevalence of AIDS in this area, the number of patients with systemic penicilliosis marneffei is found to be increasing rapidly in mainland China in recent years. We recently reviewed 668 cases of penicilliosis marneffei in mainland China from January 1984 to December 2009 in cnki, cqvip, CBMdisc and PubMed. We analyzed epidemiological and clinical features, laboratory findings, reaction to therapy and prognosis of the disease. We found that 99.4% of the cases were reported in the southern part of China; among these cases, 42.8% were from Guangxi (286 cases) and 40.6% were from Guangdong province (271 cases). Five hundred and eighty-six cases (87.7%) of penicilliosis marneffei were reported with infection by the human immunodeficiency virus, 25 cases (3.8%) with other immunocompromised diseases, and 57 cases (8.5%) without any documented underlying diseases. Fever, weight loss, anemia, lymphadenopathy, hepatosplenomegaly, respiratory signs and skin lesions were the common clinical manifestations of P. marneffei infections. The 569 cases received antifungal therapy with a mortality of 24.3% (138 cases), 99 cases who had not received antifungal therapy had a mortality of 50.6%. P. marneffei was an emerging pathogenic fungus and become a medical and public health importance in mainland China. The immunocompromised patients should pay more attention to P. marneffei infection in the endemic areas.

Comprehensive transcription analysis of human pathogenic fungus Penicillium marneffei in mycelial and yeast cells

Penicillium marneffei is a dimorphic fungus that responds to changes in temperature. We performed a comparative analysis of gene expression in mycelial- and yeast-phase P. marneffei cells using high-throughput DNA microarrays. A total of 1,884 differentially expressed genes with annotations in the gene ontology (GO) database were identified between P. marneffei mycelial and yeast cells. These differentially expressed genes mainly belong to 18 categories in the organism's ontology, including reproduction, immunity, metabolism, signaling, etc. Bioinformatics suggests that these differentially expressed genes may help explain the resistance to adverse environments and the virulence of P. marneffei. Nine genes from the results of the DNA microarray experiment were selected for further analysis with real-time quantitative PCR to validate the differential expression. Our data provide a global description of the transcriptional response accompanying adaptation to high temperature in yeast.

Penicillium marneffei infection presenting as an immune reconstitution inflammatory syndrome in an HIV patient

We describe a case of Penicillium marneffei infection acquired in Thailand, manifesting as an immune reconstitution inflammatory syndrome (IRIS) in a Caucasian man with advanced HIV-related immunosuppression (CD4 72 cells/mm3). Initial presentation was consistent with Pneumocystis jirovecii pneumonia, and empirical co-trimoxazole resulted in clinical improvement. One month after initiating antiretroviral therapy (ART), an enlarging scaly lesion on his forehead and erythematous nodules on his face, trunk and limbs developed. P. marneffei was isolated from a skin aspirate. Response to antifungal therapy was complicated by drug interactions but cure was complete after four months of treatment. Few cases of IRIS associated with P. marneffei have been reported.

Disseminated Penicillium marneffei infection in an SLE patient: a case report and literature review

Penicillium marneffei is an important opportunistic pathogen in Southeast Asia in HIV-positive individuals, but it rarely infects non-HIV ones. Four SLE patients with disseminated penicilliosis had been previously reported out of which 3 died. We describe a 46-year-old Chinese woman who had a 10 years history of SLE, associated with disseminated Penicillium marneffei infection, which presented as fever, subcutaneous masses, and fine nodular shadows disseminated over lung fields. She was initially misdiagnosed as miliary tuberculosis and panniculitis that did not respond to anti-tubercular drugs and prednisone. The correct diagnosis was finally made by histopathology and tissue culture and also culture from exudate. She responded well to antifungal therapy in the form of intravenous amphotericin B for 2 weeks followed by itraconazole plus fluconazole. The cutaneous lesions were cured leaving behind scars by secondary suture after times of epluchage, and the fine nodular shadows over lungs disappeared finally. She had no recurrence on 8 months of follow-up. We also review the literature on this topic.

Concomitant fungal and bacterial atlanto-axial osteomyelitis: a case report

Concomitant fungal and bacterial atlanto-axial osteomyelitis in immunocompetent individuals is rare. We report one such patient who underwent transoral anterior decompression and posterior occipital cervical fusion, together with antibiotic and antifungal treatment. At 16-month follow-up, the patient had made a full recovery with solid fusion. Prompt diagnosis requires a high degree of clinical suspicion, with timely use of modern imaging modalities. When the diagnosis is early, antibiotic treatment alone should suffice.

Global warming will bring new fungal diseases for mammals

Fungi are major pathogens of plants, other fungi, rotifers, insects, and amphibians, but relatively few cause disease in mammals. Fungi became important human pathogens only in the late 20th century, primarily in hosts with impaired immunity as a consequence of medical interventions or HIV infection. The relatively high resistance of mammals has been attributed to a combination of a complex immune system and endothermy. Mammals maintain high body temperatures relative to environmental temperatures, creating a thermally restrictive ambient for the majority of fungi. According to this view, protection given by endothermy requires a temperature gradient between those of mammals and the environment. We hypothesize that global warming will increase the prevalence of fungal diseases in mammals by two mechanisms: (i) increasing the geographic range of currently pathogenic species and (ii) selecting for adaptive thermotolerance for species with significant pathogenic potential but currently not pathogenic by virtue of being restricted by mammalian temperatures.

Fungal sex and pathogenesis

Human fungal pathogens are associated with diseases ranging from dandruff and skin colonization to invasive bloodstream infections. The major human pathogens belong to the Candida, Aspergillus, and Cryptococcus clades, and infections have high and increasing morbidity and mortality. Many human fungal pathogens were originally assumed to be asexual. However, recent advances in genome sequencing, which revealed that many species have retained the genes required for the sexual machinery, have dramatically influenced our understanding of the biology of these organisms. Predictions of a rare or cryptic sexual cycle have been supported experimentally for some species. Here, I examine the evidence that human pathogens reproduce sexually. The evolution of the mating-type locus in ascomycetes (including Candida and Aspergillus species) and basidiomycetes (Malassezia and Cryptococcus) is discussed. I provide an overview of how sex is suppressed in different species and discuss the potential associations with pathogenesis.