Disseminated Penicillium marneffei infection in HIV-infected subject

An Overview of Diagnostic and Management Strategies for Talaromycosis, an Underrated Disease

Underrated and neglected, talaromycosis is a life-threatening fungal disease endemic to the tropical and subtropical regions of Asia. In China, it has been reported that talaromycosis mortality doubles from 24 to 50% when the diagnosis is delayed, and reaches 100% when the diagnosis is missed. Thus, the accurate diagnosis of talaromycosis is of utmost importance. Herein, in the first part of this article, we provide an extensive review of the diagnostic tools used thus far by physicians in the management of cases of talaromycosis. The challenges encountered and the perspectives which may aid in the discovery of more accurate and reliable diagnostic approaches are also discussed. In the second part of this review, we discuss the drugs used to prevent and treat T. marneffei infection. Alternative therapeutic options and potential drug resistance reported in the contemporary literature are also discussed. We aim to guide researchers towards the discovery of novel approaches to prevent, diagnose, and treat talaromycosis, and therefore improve the prognosis for those afflicted by this important disease.

Unusual disseminated Talaromyces marneffei infection presenting with fever and diarrhea in an AIDS patient: a case report and literature review

BACKGROUND

Gastrointestinal symptoms are not uncommon in patients infected with Talaromyces marneffei (T. marneffei). However, the reports on intestinal T. marneffei infection were rare. We report a case of disseminated T. marneffei infection with intestine involvement.

CASE PRESENTATION

A 41-year-old female with acquired immune deficiency syndrome (AIDS) was admitted to our hospital for long-term fever, followed by abdominal pain and diarrhea. The colonoscopy performed in our hospital revealed ulcerative lesions in the colon and terminal ileum. Periodic acid-Schiff (PAS) staining of intestinal ulcer revealed that the small dots distributed inside and outside of the macrophages were yeast microorganisms. Further culture of bone marrow sample was confirmed T. marneffei positive. A diagnosis of disseminated T. marneffei infection was made, with intestine involvement. We also summarized the clinical characteristics, endoscopic findings and histopathological features of intestinal T. marneffei by literature review.

CONCLUSION

In HIV-infected and other immunocompromised patients with gastrointestinal symptoms and/or associated abdominal imaging abnormalities, intestinal T. marneffei infection should be taken into consideration. Serious manifestations such as intestinal obstruction and intestinal perforation may occur. Early diagnosis is of great significance to prevent the deterioration of the illness and improve the prognosis. Histopathological examination and culture of intestinal lesions are helpful to improve the diagnosis of intestinal T. marneffei infection.

ABBREVIATIONS

AIDS: acquired immune deficiency syndrome; ART: antiretroviral therapy; ESR: erythrocyte sedimentation rate; PPD:purified protein derivative; HE: Hematoxylin and eosin; PAS: Periodic acid-Schiff; CMV: cytomegalovirus; GMS:Gomori's methenamine silver nitrate.

Gastrointestinal Talaromyces marneffei infection in a patient with AIDS: A case report and systematic review

Talaromyces marneffei is a thermally dimorphic fungus that affects multiple organs and frequently invades immunocompromised individuals. However, only a few studies have reported the presence of intestinal infection associated with T. marneffei. Herein, we reported a case of intestinal T. marneffei infection in a man who complained of a 1-month history of intermittent fever, abdominal pain, and diarrhea. The result of the human immunodeficiency virus antibody test was positive. Periodic acid-Schiff and Gomorrah’s methylamine silver staining of the intestinal biopsy tissue revealed T. marneffei infection. Fortunately, the patient’s symptoms rapidly resolved with prompt antifungal treatment. In addition, we summarized and described the clinical characteristics, management, and outcomes of patients with intestinal T. marneffei infection. A total of 29 patients were identified, the majority of whom (65.52%) were comorbid with acquired immunodeficiency syndrome. The main clinical features included anemia, fever, abdominal pain, diarrhea, weight loss, and lymphadenopathy. The transverse and descending colon, ileocecum, and ascending colon were the most common sites of lesions. A considerable number of patients (31.03%) developed intestinal obstruction, intestinal perforation, and gastrointestinal bleeding. Of the 29 patients, six underwent surgery, 23 survived successfully with antifungal treatment, five died of T. marneffei infection, and one died of unknown causes. T. marneffei intestinal infection should be considered when immunodeficient patients in endemic areas present with non-specific symptoms, such as fever, abdominal pain, and diarrhea. Appropriate and timely endoscopy avoids delays in diagnosis. Early aggressive antifungal therapy improves the clinical outcomes of patients.

Talaromyces marneffei Infection: Virulence, Intracellular Lifestyle and Host Defense Mechanisms

Talaromycosis (Penicilliosis) is an opportunistic mycosis caused by the thermally dimorphic fungus Talaromyces (Penicillium) marneffei. Similar to other major causes of systemic mycoses, the extent of disease and outcomes are the results of complex interactions between this opportunistic human pathogen and a host’s immune response. This review will highlight the current knowledge regarding the dynamic interaction between T. marneffei and mammalian hosts, particularly highlighting important aspects of virulence factors, intracellular lifestyle and the mechanisms of immune defense as well as the strategies of the pathogen for manipulating and evading host immune cells.

Gastrointestinal manifestations of Talaromyces marneffei infection in an HIV-infected patient rapidly verified by metagenomic next-generation sequencing: a case report

Background

The manifestation of Talaromyces marneffei infection in some HIV-infected patients may be atypical. Cases with gastrointestinal involvement have rarely been reported. It is hard to make a diagnosis when patients are lacking the characteristic rash and positive blood culture.

Case presentation

Here, we described a patient living with HIV who complained of fever and abdominal pain, and was rapidly diagnosed with Talaromyces marneffei infection by metagenomic next-generation sequencing (mNGS) using formalin-fixation and paraffin-embedded (FFPE) samples of omentum majus tissue. We also reviewed reported related cases.

Conclusions

Talaromyces marneffei is an unusual cause of clinical presentations involving obvious abdominal pain and lower gastrointestinal bleeding, but can be included in the differential diagnosis. As an important diagnostic tool, the significance of mNGS using FFPE samples of lesions provides a more targeted diagnosis.

Recurrent Talaromyces marneffei Infection Presenting with Intestinal Obstruction in a Patient with Systemic Lupus Erythematosus

Talaromyces marneffei is an important opportunistic pathogen mainly afflicting the HIV-infected patients, in rare instance, it could cause infection in non-HIV-infected individuals. We report a 51-year-old Chinese woman who, with histories of SLE for 14 years and disseminated talaromycosis for 4 years, occurred partial intestinal obstruction that was demonstrated to be caused by Talaromyces marneffei infection. The randomly amplified polymorphic DNA results of paraffin-embedded tissues from both the present episode and the previous infection suggested that the present infection was a recurrent. The patient was performed excision of involved intestine and treated with oral itraconazole at a daily dose of 400 mg for 3 months, leading to an excellent response. However, she died with unknown reason more than a year later. We also reviewed the literature on Talaromyces marneffei infection associated with SLE as well as intestinal talaromycosis alone.

Assessment of Talaromyces Marneffei Infection of the Intestine in Three Patients and a Systematic Review of Case Reports

Background

Hematogenous dissemination of Talaromyces marneffei can result in multiorgan involvement (skin, lung, and reticuloendothelial system involvement); however, few studies have reported intestinal T marneffei infections. We investigated clinical features, management, and patient outcomes concerning Talaromyces-related intestinal infections.

Methods

Patients with Talaromycosis between August 2012 and April 2019 at The First Affiliated Hospital of Guangxi Medical University, China, were retrospectively analyzed. Patients presenting with intestinal Talaromycosis and endoscopy-confirmed diagnoses were investigated. We also undertook a systematic review of the relevant English and Chinese literature.

Results

Of 175 patients diagnosed with Talaromycosis, 33 presented with gastrointestinal symptoms, and 31 underwent stool cultures, 1 of which tested positive. Three patients had gastrointestinal symptoms and negative stool cultures, and endoscopic tissue biopsy confirmed a pathological diagnosis. A systematic review of 14 reports on human Talaromycosis identified an additional 16 patients. Fever, weight loss, and anemia were the most common symptoms, along with abdominal pain, diarrhea, and bloody stools. Abdominal computed tomography showed intestinal wall edema and thickening and/or abdominal lymphadenopathy. Endoscopy showed erosion, hyperemia, edema, and multiple intestinal mucosal ulcers. Of the 19 patients, 16 received antifungal therapy, 14 of whom recovered and 2 died. Three patients received no therapy and died.

Conclusions

Gastrointestinal disseminated Talaromycosis is not rare and can affect the stomach, duodenum, and colon, and may involve the entire digestive tract. Colon is the most common site. Endoscopy is needed for patients presenting with gastrointestinal symptoms in T marneffei-infected endemic areas. Systemic application of effective antifungal therapy can improve the prognosis.

Development and characterization of an immunochromatographic test for the rapid diagnosis of Talaromyces (Penicillium) marneffei

Talaromyces (Penicillium) marneffei is a thermally dimorphic fungus that can cause opportunistic systemic mycoses in patients infected with the human immunodeficiency virus (HIV). It has also been reported among patients with other causes of immunodeficiency, such as systemic lupus erythematosus, cancer, organ transplanted patients receiving immunosuppressive drug and adult onset immunodeficiency syndromes. Recent studies indicate that the clinical manifestations, laboratory findings and treatment strategies of talaromycosis (penicilliosis) marneffei are different between patients with and without HIV infection. Therefore early and accurate diagnosis of talaromycosis marneffei is crucial to the proper management and treatment. Since current diagnostic methods are currently inadequate, the aim of this study was to develop an immunochromatographic test (ICT) for the detection of T. marneffei yeast antigens in urine samples. The highly T. marneffei-specific monoclonal antibody 4D1 (MAb 4D1) conjugated with gold colloid at pH 6.5 was used as signal generator. The nitrocellulose membrane was lined with T. marneffei cytoplasmic yeast antigen (TM CYA) to serve as the test line, and rabbit anti-mouse IgG was the control line. Subjecting the assembled test strip to urine samples containing T. marneffei antigen produced a visible result within 20 minutes. The sensitivity limit of the assay was 3.125μg/ml of TM CYA. The ICT was used to test urine samples from 66 patients with blood culture confirmed talaromycosis marneffei, 42 patients with other fungal or bacterial infections, and 70 normal healthy individuals from endemic area of T. marneffei. The test exhibited sensitivity, specificity and accuracy of 87.87%, 100% and 95.5%, respectively. This rapid, user-friendly test holds great promise for the serodiagnosis of T. marneffei infection.

Study on the Clinical Features and Prognosis of Penicilliosis marneffei Without Human Immunodeficiency Virus Infection

OBJECTIVE

To improve the diagnosis and treatment of Penicilliosis marneffei without human immunodeficiency virus infection.

METHODS

Analyze and review the clinical features, diagnosis and treatment of six cases of P. marneffei without human immunodeficiency virus infection at The First Affiliated Hospital of Fujian Medical University.

RESULTS

Two cases were diagnosed in the ENT Department, three cases in the respiratory department and one case in the dermatological department. Penicillium marneffei infection was confirmed by sputum culture, blood culture and tissue biopsy. After definite diagnosis, one refused further treatment, and others showed significant improvement.

CONCLUSION

Penicilliosis marneffei is insidious onset and easy to be escaped and misdiagnosed. To achieve early diagnosis and appropriate treatment, doubtful cases should be alerted for the diagnoses as P. marneffei.

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

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

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.

Melanization and morphological effects on antifungal susceptibility of Penicillium marneffei

The biosynthesis of melanin has been linked with virulence in diverse pathogenic fungi. Penicillium marneffei, a dimorphic fungus, is capable of melanization in both mycelial and yeast phases, and the pigment may be produced during infection to protect the fungus from the host immune system. To investigate the impact of yeast morphological transformation on antifungal susceptibility, P. marneffei was cultured on various media including minimal medium, 1 % tryptone, brain heart infusion broth, and malt extract broth by using the standardized susceptibility protocol (the M27-A protocol, RPMI medium) for yeasts. We also investigated whether P. marneffei melanization affected its susceptibility to antifungal drugs by adding L-DOPA into culture broths. There were no differences in the minimum inhibitory concentrations of P. marneffei yeast cells previously grown in various culture broths with or without L-DOPA using the M27A protocol (into which no melanin substrate can be added due to a rapid colour change of the RPMI medium to black) for testing amphotericin B, clotrimazole, fluconazole, itraconazole and ketoconazole. However, both melanized and non-melanized P. marneffei displayed increased resistance to antifungal drugs when L-DOPA was added into a selected assay medium, 0.17 % yeast nitrogen base, 2 % glucose, and 1.5 % agar. Hence, active melanin formation appears to protect P. marneffei by enhancing its resistance to antifungal drugs.

Penicillium marneffei Infection in AIDS

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

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

BACKGROUND

Penicillium marneffei is a dimorphic pathogenic fungus endemic in Southeast Asia that usually causes disseminated disease, mainly in immunocompromised individuals, especially those with HIV infection. Untreated cases are usually fatal. The only known natural reservoir exists in bamboo rats and there is no firm evidence that these animals are involved in direct transmission to humans. The risk of infection is not restricted to those living in endemic areas; HIV-infected individuals who travel to Southeast Asia have also become infected by P. marneffei. Hence, there must exist sources to which even tourists are exposed on a short-term basis.

DESIGN AND METHODS

Penicillium is known to infect dogs and this animal is common in the streets and temple areas of Chiang Mai, where there is one of the highest incidences of P. marneffei infection in the world. Dogs have not been well studied as a possible reservoir. To investigate this possibility, we took nasal swabs from 83 outdoor dogs and performed culture and nested polymerase chain reaction (PCR) to detect P. marneffei.

RESULTS

We found that approximately 13% of nasal swabs from dogs in Chiang Mai, Thailand were positive when tested by two different PCR methods, but culture results were negative. Sequencing the products from both PCR reactions showed 100% identity with P. marneffei, whereas no other known fungi shared both sequences.

CONCLUSIONS

Our results suggest that dogs might be an animal reservoir for P. marneffei in northern Thailand. This observation should be confirmed by additional studies.

Marrow penicilliosis: a readily missed diagnosis

Penicillium marneffei is a dimorphic fungus that causes one of the most common opportunistic infections in Asian patients with AIDS. The diagnosis is established by microbiologic culture, requiring at least several days. A presumptive diagnosis can be made by cytologic or histologic examination of biopsied or aspirated tissue. Bone marrow biopsy is often performed in the workup of patients with AIDS who have fever or hematologic abnormalities and can provide prompt diagnosis of opportunistic infection. We report the bone marrow findings in the largest series of patients with culture-proven P marneffei infection. In the bone marrow, the histiocytes can occur in large numbers and be easily recognized or may be extremely subtle. P marneffei infection is sometimes not accompanied by granuloma formation despite marked histiocytic proliferation. The histiocytes contain a few to many intracellular yeast-form cells that resemble cellular debris because of their small size and staining pattern. The characteristic septate forms and the absence of budding help distinguish the condition from histoplasmosis and toxoplasmosis. Routine performance of silver methenamine stain for fungi in marrow biopsy specimens of febrile patients with AIDS is recommended to detect a subtle infection.

Cytological diagnosis of Penicillium marneffei infection

BACKGROUND/PURPOSE

Penicillium marneffei is an emerging opportunistic pathogen. The goal of this study was to study its clinical and radiographic presentation, and the diagnostic value of a cytological study of penicilliosis.

METHODS

A total of 24 patients with penicilliosis were found by culture in an 8-year period. Thirteen patients had cytological examination, which were retrospectively reviewed to analyze the morphological characteristics of P. marneffei and diagnostic yields of different cytological specimens.

RESULTS

Twenty (83%) of the 24 patients (20 males) had human immunodeficiency virus (HIV) infection. In eight (40%) patients, penicilliosis was the initial manifestation of HIV infection. Penicilliosis was diagnosed in all patients antemortem from culture of blood or other body sites. One (4%) died. Six of 13 patients who had cytological study had intra- or extracellular yeast-like organisms with transverse septum found in fine needle aspirate, imprint or sputum cytology studies. The cytological diagnostic yields for P. marneffei from lung biopsy imprint smears, lung aspirates, neck lymph node aspirates and sputum were 2/2, 2/4, 2/2 and 2/4, respectively. The cytological diagnosis could be made immediately after aspiration, much quicker than diagnosis from cultures.

CONCLUSION

P. marneffei causes disseminated infection, and can be the initial manifestation in HIV-infected patients in Taiwan. Penicilliosis can be diagnosed rapidly with cytological study of lung biopsy imprint smears, lung aspirates, neck lymph node aspirates or sputum.

In vitro antifungal-drug susceptibilities of mycelial and yeast forms of Penicillium marneffei isolates in Cambodia

Penicillium marneffei infection is an important disease among human immunodeficiency virus patients in Southeast Asia. The in vitro antifungal-drug susceptibilities of 29 clinical isolates and 5 isolates from bamboo rats collected from 2002 to 2004 were determined. The P. marneffei yeast form is more susceptible than the mycelial form to amphotericin B and ketoconazole, while the mycelial and yeast forms displayed similar susceptibilities to flucytosine and itraconazole. The MICs of fluconazole were higher for both mycelial and yeast forms.

[Penicilliosis in Laos]

INTRODUCTION

Penicilliosis is caused by Penicillium marneffei, a dimorphic fungus endemic in southeast Asia and southern China. Since 1988, this deep mycosis has been one of the most frequent opportunistic infections in subjects with HIV infection in this region. We report the first observation of penicilliosis in Laos in a subject infected by HIV.

CASE

A Laotian women with HIV infection and under treatment for tuberculosis, was hospitalized with a cough, fever and cervical lymphadenopathy. A lymph node smear stained with RAL 555 confirmed the diagnosis of penicilliosis. The histologic examination detected some Penicillium marneffei, stained by PAS and Gomori-Grocot. The patient was treated successfully with ketoconazole.

DISCUSSION

Penicilliosis is endemic in southeast Asia. Especially in Thailand, it is a common opportunistic infection in HIV-infected persons. This case confirms the existence of penicilliosis in Laos, where its prevalence as an opportunistic infection is probably underestimated. The diagnostic method (slide stained with RAL 555) used in this case is simple, rapid, and appropriate for countries with limited economic resources to devote to the penicilliosis diagnosis.

Penicillium marneffei infection and recent advances in the epidemiology and molecular biology aspects

Penicillium marneffei infection is an important emerging public health problem, especially among patients infected with human immunodeficiency virus in the areas of endemicity in southeast Asia, India, and China. Within these regions, P. marneffei infection is regarded as an AIDS-defining illness, and the severity of the disease depends on the immunological status of the infected individual. Early diagnosis by serologic and molecular assay-based methods have been developed and are proving to be important in diagnosing infection. The occurrence of natural reservoirs and the molecular epidemiology of P. marneffei have been studied; however, the natural history and mode of transmission of the organism remain unclear. Soil exposure, especially during the rainy season, has been suggested to be a critical risk factor. Using a highly discriminatory molecular technique, multilocus microsatellite typing, to characterize this fungus, several isolates from bamboo rats and humans were shown to share identical multilocus genotypes. These data suggest either that transmission of P. marneffei may occur from rodents to humans or that rodents and humans are coinfected from common environmental sources. These putative natural cycles of P. marneffei infection need further investigation. Studies on the fungal genetics of P. marneffei have been focused on the characterization of genetic determinants that may play important roles in asexual development, mycelial-to-yeast phase transition, and the expression of antigenic determinants. Molecular studies have identified several genes involved in germination, hyphal development, conidiogenesis, and yeast cell polarity. A number of functionally important genes, such as the malate synthase- and catalase-peroxidase protein-encoding genes, have been identified as being upregulated in the yeast phase. Future investigations pertaining to the roles of these genes in host-fungus interactions may provide the key knowledge to understanding the pathogenicity of P. marneffei.

Melanization of Penicillium marneffei in vitro and in vivo

Melanins are found universally in nature and are implicated in the pathogenesis of several important human fungal pathogens. This study investigated whether the conidia and the yeast cells of the thermally dimorphic fungal pathogen Penicillium marneffei produce melanin or melanin-like compounds in vitro and during infection. Treatment of conidia with proteolytic enzymes, denaturant and concentrated hot acid yielded dark particles that were similar in size and shape to the conidia. A melanin-binding monoclonal antibody (mAb) labelled pigmented conidia, yeast cells and the isolated particles as determined by immunofluorescence microscopy. Electron spin resonance spectroscopy revealed that particles derived from pigmented conidia contained a stable free radical compound, consistent with their identification as melanins. Skin tissue from penicilliosis marneffei patients contained yeast cells that were labelled by melanin-binding mAb. Additionally, sera from P. marneffei-infected mice developed a significant antibody response (both IgG and IgM) against melanin. Phenoloxidase activity capable of synthesizing melanin from l-DOPA was detected in cytoplasmic yeast cell extracts. These findings indicate that P. marneffei conidia and yeast cells can produce melanin or melanin-like compounds in vitro and that the yeast cells can synthesize pigment in vivo. Accordingly this pigment may play some role in the virulence of P. marneffei.

Clinicopathologic Study of Hepatic Penicillium marneffei in Northern Thailand

Context.—Penicillium marneffei, an opportunistic fungus, is endemic in Southeast Asia, especially in human immunodeficiency virus–infected individuals living in northern Thailand.

Objective.—We present the results of a clinicopathologic study of hepatic penicilliosis among human immunodeficiency virus/acquired immunodeficiency syndrome patients.

Design.—A search of liver biopsies in one institution from 1998 to 1999 identified 30 cases of penicilliosis.

Results.—Histologically, hepatic lesions could be classified into 1 of 3 patterns: diffuse, granulomatous, and mixed. The diffuse pattern showed a diffuse infiltration of foamy macrophages that contained numerous P marneffei. The granulomatous pattern showed a formation of multiple granulomata with various degrees of inflammatory cell infiltration. The mixed pattern showed features intermediate between the diffuse and granulomatous patterns. Liver function tests of the 3 pathologic pattern groups were evaluated, but there were no statistically significant differences in aspartate aminotransferase, alanine aminotransferase, or alkaline phosphatase levels among the various histologic groups.

Conclusion.—To our knowledge, this is the largest series to date that documents the liver pathology that results from this pathogen. We hypothesize that the histologic patterns seen on biopsy reflect the level of the host's immunity. Hence, in addition to a diagnosis of penicilliosis, a liver biopsy may also provide an assessment of the host's immune status, whereas liver function tests do not.

Antifungal therapy--state of the art at the beginning of the 21st century

The most relevant information on the present state of the art of antifungal chemotherapy is reviewed in this chapter. For dermatomycoses a variety of topical antifungals are available, and safe and efficacious systemic treatment, especially with the fungicidal drug terbinafine, is possible. The duration of treatment can be drastically reduced. Substantial progress in the armamentarium of drugs for invasive fungal infections has been made, and a new class of antifungals, echinocandins, is now in clinical use. The following drugs in oral and/or intravenous formulations are available: the broad spectrum polyene amphotericin B with its new "clothes"; the sterol biosynthesis inhibitors fluconazole, itraconazole, and voriconazole; the glucan synthase inhibitor caspofungin; and the combination partner flucytosine. New therapy schedules have been studied; combination therapy has found a significant place in the treatment of severely compromised patients, and the field of prevention and empiric therapy is fast moving. Guidelines exist nowadays for the treatment of various fungal diseases and maintenance therapy. New approaches interfering with host defenses or pathogenicity of fungal cells are being investigated, and molecular biologists are looking for new targets studying the genomics of pathogenic fungi.

Antigen detection assay for identification of Penicillium marneffei infection

Two recently produced monoclonal antibodies were used to develop an antigen capture enzyme-linked immunosorbent assay (ELISA) for rapid diagnosis of Penicillium marneffei. The method was evaluated with 53 patients with culture-confirmed penicilliosis and 240 controls. The diagnostic sensitivity, specificity, and accuracy of the ELISA were 92.45, 97.5, and 96.59%, respectively.

Penicilliosis marneffei: another AIDS defining illness in Southeast Asia

Penicilliosis marneffei, a common mycosis among AIDS patients living in Southeast Asia, has been recently suggested for inclusion in the AIDS surveillance case definition. Infections with Penicillium marneffei were rare in the past, but infections with this dimorphic fungus have increased with the endemic of AIDS in the region. The reservoir of P. marneffei in nature is still unknown, although it seems likely that inhalation may be the route of entry of the organism leading to infection in humans. P. marneffei can cause two clinical types of the disease; focal and fatal progressive, disseminated infections, characterized by a variety of symptoms which can mimic those of other diseases. Oral P. marneffei lesions usually occur in patients with disseminated infections, presenting as shiny papules, as erosions or as shallow ulcers covered with whitish yellow, necrotic slough which may be found on the palate, gingiva, labial mucosa, tongue and oropharynx. Biopsy and culture provide definitive diagnoses, while serologic tests for both antibody and antigen are useful in rapid presumptive diagnoses as well as in surveillance studies of the prevalence and latency of the infection. Penicilliosis marneffei is a treatable disease, but late diagnosis and treatment may be fatal. Itraconazole and ketoconazole are the drugs of first choice for mild to moderately severe forms of the disease, whereas parenteral therapy with amphotericin B may be required for seriously ill patients. Recurrence of the disease is common, therefore maintenance is recommended. As reported, prophylaxis generating resistant strains are likely to develop.

Recognition of fibronectin by Penicillium marneffei conidia via a sialic acid-dependent process and its relationship to the interaction between conidia and laminin

Adhesion of Penicillium marneffei conidia to the extracellular matrix protein laminin via a sialic acid-dependent process has previously been demonstrated. This study describes the interaction of P. marneffei conidia with fibronectin and examines the relationship of this process to the recognition of laminin via conidia. Immunofluorescence microscopy demonstrated that fibronectin bound to the surface of conidia and to phialides, but not to hyphae, in a pattern similar to that reported for laminin. Conidia were able to bind to fibronectin immobilized on microtiter plates in a concentration-dependent manner. However, binding to fibronectin (at any given concentration of protein and conidia) was less than that to laminin under equivalent conditions. Soluble fibronectin and antifibronectin antibody inhibited adherence of conidia to fibronectin in the plate adherence assay; soluble laminin also caused pronounced inhibition. Various monosaccharides and several peptides had no effect on adherence to fibronectin. However, N-acetylneuraminic acid abolished adherence to fibronectin, indicating that the interaction was mediated through a sialic acid-dependent process; the latter parallels observations of laminin binding by conidia. Fibronectin binding (and binding of laminin) was considerably reduced by prolonged preincubation of conidia with chymotrypsin, suggesting the protein nature of the binding site. Conidia from older cultures were more adherent to both immobilized fibronectin and laminin than conidia from younger cultures. Ligand affinity binding demonstrated the presence of a 20-kDa protein with the ability to bind both fibronectin and laminin. There would therefore appear to be a common receptor for the binding of fibronectin and laminin on the surface of P. marneffei, and the interaction described here maybe important in mediating attachment of the fungus to host tissue.

Detection of cell wall mannoprotein Mp1p in culture supernatants of Penicillium marneffei and in sera of penicilliosis patients

Mannoproteins are important and abundant structural components of fungal cell walls. The MP1 gene encodes a cell wall mannoprotein of the pathogenic fungus Penicillium marneffei. In the present study, we show that Mp1p is secreted into the cell culture supernatant at a level that can be detected by Western blotting. A sensitive enzyme-linked immunosorbent assay (ELISA) developed with antibodies against Mp1p was capable of detecting this protein from the cell culture supernatant of P. marneffei at 10(4) cells/ml. The anti-Mp1p antibody is specific since it fails to react with any protein-form lysates of Candida albicans, Histoplasma capsulatum, or Cryptococcus neoformans by Western blotting. In addition, this Mp1p antigen-based ELISA is also specific for P. marneffei since the cell culture supernatants of the other three fungi gave negative results. Finally, a clinical evaluation of sera from penicilliosis patients indicates that 17 of 26 (65%) patients are Mp1p antigen test positive. Furthermore, a Mp1p antibody test was performed with these serum specimens. The combined antibody and antigen tests for P. marneffei carry a sensitive of 88% (23 of 26), with a positive predictive value of 100% and a negative predictive value of 96%. The specificities of the tests are high since none of the 85 control sera was positive by either test.

Detection of specific antibodies to an antigenic mannoprotein for diagnosis of Penicillium marneffei penicilliosis

The disseminated and progressive fungal disease Penicillium marneffei penicilliosis is one of the most common infectious diseases in AIDS patients in Southeast Asia. To diagnose systemic penicilliosis, we developed an enzyme-linked immunosorbent assay (ELISA)-based antibody test with Mp1p, a purified recombinant antigenic mannoprotein of P. marneffei. Evaluation of the test with guinea pig sera against P. marneffei and other pathogenic fungi indicated that this assay was specific for P. marneffei. Clinical evaluation revealed that high levels of specific antibody were detected in two immunocompetent penicilliosis patients. Furthermore, approximately 80% (14 of 17) of the documented penicilliosis patients with human immunodeficiency virus tested positive for the specific antibody. No false-positive results were found for serum samples from 90 healthy blood donors, 20 patients with typhoid fever, and 55 patients with tuberculosis, indicating a high specificity of the test. Thus, this ELISA-based test for the detection of anti-Mp1p antibody can be of significant value as a diagnostic for penicilliosis.

Epidemiology and management of penicilliosis in human immunodeficiency virus-infected patients

Penicillium marneffei is a dimorphic fungus that can cause systemic mycosis in humans. It is endemic in Southeast Asia, the Guangxi province of China, Hong Kong, and Taiwan. Prior to the epidemic of human immunodeficiency virus (HIV), penicilliosis was a rare event. The incidence of this fungal infection has increased markedly during the past few years, paralleling the incidence of HIV infection. The patients usually present with fever, anemia, weight loss, skin lesions, generalized lymphadenopathy, and hepatomegaly. The skin lesions are most commonly papules with central necrotic umbilication. The average number of CD4+ T lymphocytes at presentation is 64 cells/mm3. The fungus is usually sensitive to amphotericin B, itraconazole, and ketoconazole. The response to antifungal treatment is good if the treatment is started early. After the initial treatment the patient may need to take an antifungal drug as secondary prophylaxis for life. New tests for the laboratory diagnosis of penicilliosis have been reported. Further studies of these tests, as well as the epidemiology, natural history, and management of this potentially fatal systemic fungal infection are needed.

Diagnostic utility of bone marrow sampling in HIV positive patients

OBJECTIVE

To evaluate the diagnostic utility of bone marrow (BM) sampling in HIV positive patients.

DESIGN

Retrospective cohort analysis.

SETTING

Specialist HIV/AIDS service in London.

SUBJECTS

215 consecutive HIV infected patients undergoing 246 BM samplings for investigation of pyrexia without localising signs, haematological abnormalities, or staging/investigation of lymphoma.

MAIN OUTCOME MEASURE

Diagnostic yield from (and impact on management of) BM sampling.

RESULTS

Of 122 BM samples taken to investigate pyrexia, 33 (27%) revealed the cause on microscopy: unexpected lymphoma in seven (6%), mycobacteriosis in 25 (20%), and toxoplasmosis in one (1%). Marrow infiltration was confirmed in 11 of 38 BM samples taken for staging/investigation of lymphoma/leukaemia. In afebrile patients, of 22 with pancytopenia, BM samples showed HIV associated changes in 17 and specific diagnoses in five (mycobacterial infection in three, haemophagocytic syndrome in one, and megaloblastic change due to vitamin B-12 deficiency in one); of 21 with isolated thrombocytopenia, 20 (95%) BM samples showed immune thrombocytopenic purpura to be the cause and the remaining patient had BM changes of aplasia; of 29 with isolated anaemia, 28 had BM changes of HIV associated dysplasia/erythroid dysplasia and one had unsuspected iron deficiency; all 10 with isolated leucopenia/neutropenia had BM changes ascribed to HIV infection exacerbated by concurrent sepsis or medication; of four BM samples taken for other reasons, one showed mycobacterial infection.

CONCLUSIONS

BM sampling has diagnostic utility in HIV infected patients with pyrexia without localising signs, pancytopenia, and staging/investigation of lymphoma; this test has little value in the investigation of afebrile patients with isolated thrombocytopenia, anaemia, or leucopenia as HIV is usually the underlying cause.

Western immunoblot analysis of protein antigens of Penicillium marneffei

Protein antigens of Penicillium marneffei prepared during the yeast and mould phases of in vitro growth were analyzed by gel electrophoresis and immunoblot assay. More than 20 yeast phase proteins were detected by Coomassie staining; among these, at least 10 reacted with IgG in the pooled sera of 28 AIDS patients with penicilliosis. Four immunogenic proteins of 200, 88, 54 and 50 kDa were produced in large quantity during the deceleration and early stationary phases of growth. When these proteins were reacted with individual sera derived from 33 AIDS patients with penicilliosis, reactivities to the 200, 88, 54 and 50 kDa protein were detected in 72.7, 93.9, 60.6 and 57.6%, respectively. The bands of 88, 54 and 50 kDa gave strong reactions with about a half of serum samples. In one serum derived from an AIDS patient, reactivities to the 54 and 50 kDa proteins could be strongly detected two months before the definite diagnosis by fungal culture. Protein components from the mould form were of lower yield and gave weaker signal in immunoblot analysis. These results indicate that at least two yeast-phase immunoreactive proteins (54 and 50 kDa) are relatively specific to the P. marneffei infection, thereby suggesting its potential for clinical application to the diagnosis of this emerging disease.

Unusual cause of fever and diarrhea in a patient with AIDS. Penicillium marneffei infection

Penicillium marneffei is an opportunistic pathogen predominantly found in Southeast Asia. Systemic infection of Penicillium marneffei has protean manifestations including fever, weight loss, anaemia, skin lesions, and lymphadenopathy. We report a rare case of penicillium colitis in an AIDS patient who responded successfully to a course of amphotericin B therapy.

Penicillium marneffei infection in a patient with SLE

We describe a patient with SLE who was infected by the fungus Penicillium marneffei. She was initially misdiagnosed as having disseminated tuberculosis. The correct diagnosis was finally made by bone marrow culture and she responded to a prolonged course of amphotericin B, flucytosine and itraconazole. The clinical presentation and histology of penicilliosis are very similar to those of Mycobacterium tuberculosis. In Southeast Asia, penicilliosis should be considered as a differential diagnosis in patients with SLE who present with fever and lymphadenopathy.

Disseminated Penicillium marneffei: presenting illness of advanced HIV infection; a clinicopathological review, illustrated by a case report

BACKGROUND

Until recently Penicillium marneffei rarely caused human disease. It is now a frequently encountered opportunistic mycosis in HIV positive residents of, and travellers to, south-east Asia.

AIMS

To review aspects of clinical presentation, pathology, treatment, epidemiology and ecology of P. marneffei. To report a case of disseminated P. marneffei occurring in the Northern Territory which illustrates many typical clinical and pathological features of this infection.

CASE PRESENTATION

A Burmese immigrant presented to Royal Darwin Hospital, Australia with a non-specific, subacute, febrile illness and a diffuse papular rash. The etiological agent was Penicillium marneffei, disseminated in association with advanced HIV infection. The typical travel history and umbilicated papular rash were recognized on admission. Fungal stains of skin biopsies and touch smears facilitated rapid diagnosis, and early antifungal therapy resulted in clinical cure.

CONCLUSIONS

Early distinction of penicilliosis from other opportunistic mycoses, tuberculosis, Leishmaniasis, and molluscum contagiosum is critical for effective management. The characteristic histological and mycological properties of P. marneffei are easily recognizable if the diagnosis is considered. In view of geographic proximity, travel and immigration from endemic areas, Australia should expect further imported penicilliosis as illustrated by this case report.

Phylogeny and PCR identification of the human pathogenic fungus Penicillium marneffei

The phylogenetic position of the human pathogenic fungus Penicillium marneffei was assessed from the nucleotide sequences of the nuclear and mitochondrial ribosomal DNA regions. Phylogenetic analysis determined that P. marneffei is closely related to species of Penicillium subgenus Biverticillium and sexual Talaromyces species with asexual biverticillate Penicillium states. Knowledge of the phylogenetic position of P. marneffei facilitated the design of unique oligonucleotide primers, from the nuclear ribosomal DNA internal transcribed spacer region, for the specific amplification of P. marneffei DNA. These primers were successful at selectively amplifying DNA from six isolates of P. marneffei and excluding the other species tested, which included Penicillium subgenus Biverticillium and Talaromyces species and several well-known fungal pathogens, namely, Aspergillus fumigatus, Coccidioides immitis, Histoplasma capsulatum, and Pneumocystis carinii. The primers that we have developed for the specific amplification of P. marneffei have the potential to be incorporated in a PCR identification system which could be used for the identification of this pathogenic agent from clinical material.

Penicilliosis marneffei infection in AIDS

Penicillium marneffei infection has emerged as a new potential indicator disease for AIDS in Southeast Asia. We report two additional cases of P. marneffei infection in patients infected with HIV who had traveled to endemic areas and review the mucocutaneous features of previously reported cases. Our two patients had many of the typical features associated with invasive infection: fever, weight loss, anemia, lymphadenopathy, hepatomegaly, pulmonary and gastrointestinal symptoms, as well as skin manifestations such as papular molluscum contagiosum-like lesions and oral lesions. Knowledge of cutaneous signs is important for prompt diagnosis of P. marneffei infection and institution of life-saving therapy with antifungal agents.