Endoscopic diagnosis of intestinal penicilliosis marneffei: report of three cases and review of the literature

Clinical Characteristics and Outcomes of Endemic Mycoses After Solid Organ Transplantation: A Comprehensive Review

Background

Geographically endemic fungi can cause significant disease among solid organ transplant (SOT) recipients. We provide an update on the epidemiology, clinical presentation, and outcomes of 5 endemic mycoses in SOT recipients.

Methods

Multiple databases were reviewed from inception through May 2023 using key words for endemic fungi (eg, coccidioidomycosis or Coccidioides, histoplasmosis or Histoplasma, etc). We included adult SOT recipients and publications in English or with English translation.

Results

Among 16 cohort studies that reported on blastomycosis (n = 3), coccidioidomycosis (n = 5), histoplasmosis (n = 4), and various endemic mycoses (n = 4), the incidence rates varied, as follows: coccidioidomycosis, 1.2%-5.8%; blastomycosis, 0.14%-0.99%; and histoplasmosis, 0.4%-1.1%. There were 204 reports describing 268 unique cases of endemic mycoses, including 172 histoplasmosis, 31 blastomycosis, 34 coccidioidomycosis, 6 paracoccidioidomycosis, and 25 talaromycosis cases. The majority of patients were male (176 of 261 [67.4%]). Transplanted allografts were mostly kidney (192 of 268 [71.6%]), followed by liver (n = 39 [14.6%]), heart (n = 18 [6.7%]), lung (n = 13 [4.9%]), and combined kidney-liver and kidney-pancreas (n = 6 [2.7%]). In all 5 endemic mycoses, most patients presented with fever (162 of 232 [69.8%]) and disseminated disease (179 of 268 [66.8%]). Cytopenias were frequently reported for histoplasmosis (71 of 91 [78.0%]), coccidioidomycosis (8 of 11 [72.7%]) and talaromycosis (7 of 8 [87.5%]). Graft loss was reported in 12 of 136 patients (8.8%). Death from all-causes was reported in 71 of 267 (26.6%); half of the deaths (n = 34 [50%]) were related to the underlying mycoses.

Conclusions

Endemic mycoses commonly present with fever, cytopenias and disseminated disease in SOT recipients. There is a relatively high all-cause mortality rate, including many deaths that were attributed to endemic mycoses.

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.

Clinical Characteristics of Transplant Recipients Infected with Talaromyces Marneffei: 2 Case Reports and a Literature Review

Purpose

To summarize the clinical characteristics, treatment and outcomes of transplant recipients infected with Talaromyces marneffei (TM).

Materials and Methods

A retrospective analysis was performed on 2 patients with Talaromycosis marneffei (TSM) and transplants at the First Affiliated Hospital of Guangxi Medical University, and a systematic literature review was conducted simultaneously.

Results

This article reported two patients after kidney transplantation who developed fever, cough within 3-4 months. Their haemoglobin was decreased. Their chest computed tomography (CT) showed nodules. TM was detected in their blood or bronchoalveolar lavage fluid samples by next-generation sequencing (NGS). After antifungal treatment with voriconazole (VOR), one patient worsened, the other patient died. A total of 21 patients with TSM after transplants were reported in the literature review. Fourteen underwent kidney transplantation, 4 underwent liver transplantation, 2 underwent lung transplantation, and 1 underwent bone marrow transplantation. The median time from initiating the postoperative immunosuppressive therapy to the onset of symptoms or disease changes was 18 (0.5-140) months. Among them, 9 patients developed fever, 7 patients developed cough or expectoration and 4 patients developed dyspnoea. Haemoglobin was decreased in 10 patients. Pulmonary nodules were found in 7 patients. Among the 21 patients, 7 were diagnosed by positive culture, 6 by biopsy, 5 by culture and biopsy. Of the 21 patients, 13 patients improved by antifungal therapy, 8 patients worsened or died. Seven patients who received amphotericin B followed by itraconazole (ITR) therapy all improved. Regarding the use of immunosuppressants in 12 patients, 9 patients had to discontinue or reduce their medications (6 patients improved, 3 patients worsened or died).

Conclusion

Patients with TSM after transplant often have disseminated infections, involving the respiratory, hematopoietic and so on. Fever, cough, decreased haemoglobin and pulmonary nodules often occur approximately 18 months after surgery. The combined applications of culture, biopsy, NGS are helpful for an early diagnosis. Antifungal therapy with amphotericin B followed by itraconazole is recommended, and the dosage of the immunosuppressant should be adjusted timely.

Successful treatment of Talaromyces marneffei infection in a kidney transplant recipient with voriconazole followed by itraconazole for the first time

Talaromyces (Penicillium) marneffei (T. marneffei) is an important pathogenic thermally dimorphic fungus in Southeast Asia that leads to a life-threatening systemic mycosis in immunodeficient hosts, especially in AIDS patients. With the increasing AIDS epidemic, the number of patients with T. marneffei infections in mainland China has increased rapidly in recent years. The infection can be life-threatening in people with immunodeficiencies, such as HIV, organ transplantations, autoimmune diseases, and malignant tumors. Here, we present a disseminated T. marneffei infection case in a renal transplant recipient successfully treated with voriconazole followed by itraconazole. We describe the patient's clinical progression from onset symptoms to recovery and review the additional 14 published cases with T. marneffei infections in renal transplant recipients. In addition, we discuss the route of infection and treatment strategies of T. marneffei. Our data suggest that patients with kidney transplantations in T. marneffei infection-endemic areas should presume the possibility of infection and initiate appropriate antifungal treatment.

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

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

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.

The Mycobiome in Health and Disease: Emerging Concepts, Methodologies and Challenges

Fungal disease is an increasingly recognised global clinical challenge associated with high mortality. Early diagnosis of fungal infection remains problematic due to the poor sensitivity and specificity of current diagnostic modalities. Advances in sequencing technologies hold promise in addressing these shortcomings and for improved fungal detection and identification. To translate such emerging approaches into mainstream clinical care will require refinement of current sequencing and analytical platforms, ensuring standardisation and consistency through robust clinical benchmarking and its validation across a range of patient populations. In this state-of-the-art review, we discuss current diagnostic and therapeutic challenges associated with fungal disease and provide key examples where the application of sequencing technologies has potential diagnostic application in assessing the human ‘mycobiome’. We assess how ready access to fungal sequencing may be exploited in broadening our insight into host–fungal interaction, providing scope for clinical diagnostics and the translation of emerging mycobiome research into clinical practice.

Emerging fungal infections in solid organ transplant recipients: Guidelines of the American Society of Transplantation Infectious Diseases Community of Practice

These updated AST-IDCOP guidelines review the epidemiology, diagnosis, and management of emerging fungi after organ transplantation. Infections due to numerous generally innocuous fungi are increasingly recognized in solid organ transplant (SOT) recipients, comprising about 7%-10% of fungal infections in this setting. Such infections are collectively referred to as emerging fungal infections and include Mucormycetes, Fusarium, Scedosporium, and dematiaceous fungi among others. The causative organisms are diverse in their pathophysiology, uncommon in the clinical setting, have evolving nomenclature, and are often resistant to multiple commonly used antifungal agents. In recent years significant advances have been made in understanding of the epidemiology of these emerging fungal infections, with improved diagnosis and expanded treatment options. Still, treatment guidelines are generally informed by and limited to experience from cohorts of patients with hematological malignancies and/or solid and stem cell transplants. While multicenter randomized controlled trials are not feasible for these uncommon infections in SOT recipients, collaborative prospective studies can be valuable in providing information on the epidemiology, clinical manifestations, treatment strategies, and outcomes associated with the more commonly encountered infections.

Inflammatory and infectious manifestations of immunodeficiency in the gastrointestinal tract

Immune compromise may result from genetic abnormalities, HIV/AIDS, or consequences of therapy for neoplastic and autoimmune diseases. Many immunocompromised patients develop severe gastrointestinal symptoms, particularly diarrhea, accompanied by non-specific or mild endoscopic abnormalities; mucosal biopsy with pathologic interpretation has a major role in the diagnosis and management of these patients. Immunocompromised individuals are at risk for all the diseases that affect those with a healthy immune system, but they are also prone to other illnesses that rarely affect immunocompetent patients. This review discusses the gastrointestinal manifestations of primary and acquired immunodeficiency, chemotherapy-related injury, and infections that show a predilection for immunocompromised patients. Key histologic features and relevant differential diagnoses are emphasized.

Recovery from Talaromyces marneffei involving the kidney in a renal transplant recipient: A case report and literature review

Talaromyces marneffei is an emerging opportunistic infection among immunocompromised patients. We observe the first native case of disseminated T. marneffei involving the kidney in a renal transplant recipient in mainland China. We describe the comprehensive clinical course, and ultrasound imaging of renal transplant biopsy, pathologic images, and electron microscopy observation of the biopsy specimen, highlighting the relevance of biopsy findings and the blood culture. We also focus on the treatment and good outcome of the patient. Then we review the literature and show the additional 10 reported cases of T. marneffei in renal transplant recipients. In addition, we discuss the new methods of rapid diagnosis of T. marneffei. In brief, timely diagnosis and proper treatment of T. marneffei infection is important in renal transplant recipients.

Gastrointestinal Infections

Gastrointestinal infections in the immunocompromised host are caused by the common bacterial, viral, fungal, and parasitic agents that also cause infections in the immunocompetent host. Of special consideration is that immunocompromised patients may be at increased risk for infection or disease severity and by pathogens not seen in the competent host. This chapter reviews the various agents, risk factors, and diagnostic approaches to detect gastrointestinal infections in this patient population.

Talaromyces (Penicillium) marneffei infection in non-HIV-infected patients

Talaromyces (Penicillium) marneffei is an important pathogenic thermally dimorphic fungus causing systemic mycosis in Southeast Asia. The clinical significance of T. marneffei became evident when the human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome epidemic arrived in Southeast Asia in 1988. Subsequently, a decline in the incidence of T. marneffei infection among HIV-infected patients was seen in regions with access to highly active antiretroviral therapy and other control measures for HIV. Since the 1990s, an increasing number of T. marneffei infections have been reported among non-HIV-infected patients with impaired cell-mediated immunity. Their comorbidities included primary adult-onset immunodeficiency due to anti-interferon-gamma autoantibodies and secondary immunosuppressive conditions including other autoimmune diseases, solid organ and hematopoietic stem cell transplantations, T-lymphocyte-depleting immunsuppressive drugs and novel anti-cancer targeted therapies such as anti-CD20 monoclonal antibodies and kinase inhibitors. Moreover, improved immunological diagnostics identified more primary immunodeficiency syndromes associated with T. marneffei infection in children. The higher case-fatality rate of T. marneffei infection in non-HIV-infected than HIV-infected patients might be related to delayed diagnosis due to the lack of clinical suspicion. Correction of the underlying immune defects and early use of antifungals are important treatment strategies. Clinicians should be familiar with the changing epidemiology and clinical management of T. marneffei infection among non-HIV-infected patients.

Penicillium marneffei infection in a lung transplant recipient

Penicillium marneffei is a thermally dimorphic fungus that can cause severe opportunistic infections in endemic regions of Southeast Asia, particularly in individuals infected with human immunodeficiency virus-1, but has rarely been reported in solid organ transplant recipients. Herein, we report the first case, to our knowledge, of P. marneffei infection in a lung transplant recipient, occurring in a 41-year-old woman 28 months post lung transplantation, after recent travel to Vietnam. We have reviewed the literature to derive some management principles for this rare infection in this clinical context. The number of P. marneffei infections in transplant recipients may increase, as a result of increasing rates of transplantation and travel to endemic areas.

Fungal infection of the colon

Fungi are pathogens that commonly infect immunocompromised patients and can affect any organs of the body, including the colon. However, the literature provides limited details on colonic infections caused by fungi. This article is an intensive review of information available on the fungi that can cause colon infections. It uses a comparative style so that its conclusions may be accessible for clinical application.

Acute Abdomen Due to Penicillium marneffei: An Indicator of HIV Infection in Manipur State

Opportunistic infection in HIV disease often present to clinicians in an atypical manner testing clinical acumen. Here, we report a case of Penicilliosis marneffei (PM) infection presenting to surgical emergency as acute abdomen with undiagnosed HIV status in advanced AIDS, chief complaints being prolonged fever and diffuse abdominal pain. Radiologic imaging showed non-specific mesenteric and retroperitoneal lymphadenopathy. Fine needle aspiration cytology (FNAC) of the lymph node was done and subjected to direct microscopy, gram staining and culture on Sabouraud's dextrose agar (SDA) which showed Penicillium marneffei. He was then treated with intravenous amphotericin. This case is reported for its rarity and unusual presentation to sensitise clinicians and microbiologists to consider PM as an aetiology in acute abdomen in high risk individuals, more so, in patients from north-east India.

Fungal infections of the gastrointestinal tract in the immunocompromised host: an update

Fungal infections are one of the most significant causes of morbidity and mortality in immunocompromised patients. The incidence of invasive fungal infections, including those of the gastrointestinal tract, has increased significantly as numbers of immunocompromised patients have increased. The diagnosis of fungal infections in immunocompromised patients may be particularly problematic as these patients may present with atypical clinical features. Although Candida and Aspergillus species represent the majority of fungi diagnosed in the immunocompromised patient population, other fungi are emerging as increasingly common pathogens, and this review will focus on several important emerging fungal infections in immunocompromised patients.

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.

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.

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Gastrointestinal infections in the immunocompromised host

Gastrointestinal disease is a significant cause of morbidity and mortality in the immunocompromised patient. This article focuses on the infectious gastrointestinal complications associated with the treatment of malignant disease and with solid organ transplantation but not HIV. Gastrointestinal defenses and the various mechanisms by which they are impaired are reviewed. The major pathogens and malignancies of this patient population and an approach to their diagnosis, treatment, and prevention are discussed.

Gastrointestinal infections in the immunocompromised host

The gastrointestinal tract is a common site of infection in the opportunistic host. Pathogens range from highly virulent organisms, which infect people with well functioning immune systems as well as people with poorly functioning immune systems, to opportunistic organisms, which infect only those with impaired immune systems. Viruses, bacteria, fungi, and protozoa lead to disease that can be especially severe, debilitating, and difficult to treat in the immunocompromised host. Yet in this era of highly active antiretroviral therapy for HIV-infected patients and strategies to reduce immunosuppression in transplant and oncology patients, appropriate diagnostic tests and treatment can both improve the quality of life and decrease mortality. In this article, I review the changing pathogenesis, epidemiology, clinical presentation, diagnosis, and treatment of gastrointestinal infections in the immunocompromised host.

Endoscopy in acquired immunodeficiency syndrome patients with diarrhea and negative stool studies

BACKGROUND

Diarrhea is a frequent gastrointestinal symptom in patients with acquired immuno-deficiency syndrome (AIDS) and is a major source of morbidity and mortality. A stepwise diagnostic approach is often recommended to search for treatable causes. However, whether the stepwise diagnostic approach is adequate for planning treatment and whether specific treatment for infectious etiologies will affect the survival of patients with AIDS remain unknown.

METHODS

From March 1996 to September 1997, endoscopy was performed in AIDS patients with diarrhea, the etiology of which was not identified by noninvasive methods. Specific treatment was given according to the identified etiologies and symptomatic treatment was given for those without definite diagnosis. The clinical symptoms, signs, and duration of follow-up were recorded and survival patterns were analyzed.

RESULTS

Etiologic diagnoses were made in 26 of 40 patients (65%) who underwent endoscopic studies. Amebic colitis and cytomegalovirus colitis were the 2 leading causes of prolonged diarrhea in patients with AIDS. Thirty-five patients (87.5%) recovered after treatment. The difference in survival time after diarrhea between patients whose symptoms resolved after treatment and those who continued to have diarrhea was statistically significant (p < 0.001).

CONCLUSIONS

Endoscopic studies were helpful for the diagnosis of prolonged diarrhea in AIDS patients who had negative stool studies and did not respond to 2 weeks of empiric treatment. Specific treatment according to the results of endoscopy may improve survival in these patients.

Penicillium marneffei: an insurgent species among the penicillia

Most species of Penicillium are considered relatively benign with respect to causing human disease. However, one species, P. marneffei, has emerged as a significant pathogen particularly among individuals who live in Southeast Asia and are concurrently infected with the human immunodeficiency virus. While environmental and epidemiological studies have yet to resolve the reason for the heightened virulence of P. marneffi, one characteristic does distinguish this fungus from other Penicillium species. Whereas the latter grow as monomorphic moulds bearing typical asexual propagules (conidia), P. marneffei is thermally dimorphic. At room temperature, P. marneffei exhibits the morphology characteristic of the genus. In contrast to other Penicillia, though, P. marneffei grows as a yeast-like entity (arthroconidium) when found in diseased tissue or cultivated at 37 degrees C. Studies in our laboratory have focused on the differential gene expression between the mould and arthroconidial phases. Many of the genes whose expression differs during mould-to-arthrocondium transition are related to energy metabolism. A better understanding of gene expression during morphogenesis in P. marneffei may help detect unique target sites or cellular processes that can be exploited in the development of antifungal agents or immunomodulation therapies.