Gastrointestinal histoplasmosis in the acquired immunodeficiency syndrome: report of 18 cases and literature review

Gastrointestinal histoplasmosis with small intestinal perforation: 20-year experience

Postmortem studies show gastrointestinal tract involvement in as many as 70% of patients affected by disseminated histoplasmosis. Although gastrointestinal involvement is common in disseminated disease, the presentation of small intestinal perforation is exceedingly rare with few reported cases in the literature. Herein we present our institutional case series. The aim of the study is to describe small intestinal perforation in gastrointestinal histoplasmosis with attention to management and outcomes. This is a retrospective single-institution review of patients ≥ 18 years of age treated for small intestinal perforation due to gastrointestinal histoplasmosis. A prospectively maintained institutional database was searched from 2002 to 2022. Data obtained included demographics, comorbidities, treatment course, and outcomes. Five patients with a mean age of 54 years (range 25-72) were identified. Pertinent underlying comorbid conditions included Crohn's disease, psoriatic arthritis, rheumatoid arthritis, and solid organ transplantation. All patients were on chronic immunosuppressive medication(s) with the most common being tumor necrosis factors alpha inhibitors and corticosteroids. Four had a clinical diagnosis of perforation based on physical examination and imaging. All patients underwent segmental resection(s) of the small intestine and received medical treatment with intravenous amphotericin B and eventual transition to an oral antifungal. No patients experienced complications related to surgery. The limitations of the study include nonrandomized retrospective review, single-institution experience, and small patient sample size. Although rare, histoplasmosis should be considered in the differential of patients on chronic immunosuppressive therapy who present with gastrointestinal symptoms concerning perforation, especially from endemic areas. Small intestinal perforation due to gastrointestinal histoplasmosis can be successfully treated with resection and antifungal therapy.

A Complex Case of Histoplasmosis in an Immunocompromised Patient: Diagnostic Challenges, Multidisciplinary Collaboration, and Environmental Factors

Histoplasmosis is a systemic fungal infection caused by Histoplasma capsulatum, known for its protean clinical manifestations that often pose diagnostic challenges. Immunocompromised patients, such as those on immunosuppressive therapies or with HIV/AIDS, are particularly susceptible to severe forms of the disease. We present a case of a 55-year-old female with a complex medical history, including a renal transplant, who developed fever, malaise, nausea, and vomiting after a month-long stay in Panama. The patient's history included exposure to a bird with apparent infection and mold in her home. Her clinical presentation featured acute kidney injury, elevated liver enzymes, acalculous cholecystitis, and lung nodules. This intricate constellation of symptoms underscores the diverse nature of histoplasmosis presentations and its potential to mimic other diseases. The patient underwent a stepwise diagnostic approach involving imaging, microbiological tests, and multidisciplinary consultations. The positive Fungitell assay, Histoplasma capsulatum detection in urine, and identification of scattered subcentimeter lung nodules confirmed the diagnosis. This case underscores the significance of considering endemic areas, environmental exposures, and atypical clinical features in immunocompromised patients. The multidisciplinary approach facilitated appropriate management and treatment initiation with liposomal amphotericin B, highlighting the importance of collaboration among various medical specialties in complex cases. As such, this case report emphasizes the complexity of diagnosing and managing histoplasmosis in immunocompromised individuals and highlights the need for a comprehensive evaluation of atypical presentations.

Gastrointestinal histoplasmosis presenting as a small bowel obstruction in an immunocompetent patient

The clinical presentation of gastrointestinal histoplasmosis (GIH) is often non-specific, mimicking several other gastrointestinal diseases, making diagnosis difficult. We present a case of GIH, causing bowel obstruction in an immunocompetent patient. A woman in her 80s presented with anorexia and a distended abdomen. A CT scan of the abdomen and pelvis (CTAP) showed ileal thickening. Endoscopy was performed and ileal biopsies were taken. A diagnosis of histoplasmosis was made by histopathology, and she began treatment with liposomal amphotericin and itraconazole. Despite presenting well at her routine follow-up appointments, she presented 4 months after diagnosis with worsening symptoms of anorexia and abdominal distention. CTAP showed the ileal stricture causing bowel obstruction. She underwent itraconazole and steroid treatment while having nasogastric tube decompression. Subsequent gastrografin follow through showing partial obstruction and surgical resection was planned. Unfortunately, her condition deteriorated, her kidney function worsened and she suffered from aspiration pneumonia with eventual demise.

Mimics of Crohn's Disease

Crohn's disease is a chronic inflammatory disease that can affect any portion of the gastrointestinal tract. Associated symptoms can vary based on the severity of disease, extent of involvement, presence of extraintestinal manifestations, and development of complications. Diagnosis is based on a constellation of findings. Many diseases can mimic Crohn's disease and lead to diagnostic conundrums. These include entities associated with the gastrointestinal luminal tract, vascular disease, autoimmune processes, various infections, malignancies and complications, drug- or treatment-induced conditions, and genetic diseases. Careful consideration of possible causes is necessary to establish the correct diagnosis.

Viral Acute Gastroenteritis in Special Populations

Viral acute gastroenteritis (AGE) is common and afflicts people of all ages. Nonviral causes of AGE are less common. Norovirus is a leading cause of sporadic cases and outbreaks of AGE across all ages. Universal rotavirus vaccination of infants has reduced frequency and severity of rotavirus AGE cases in children and indirectly reduced cases in older adults. Severe illness is more likely in persons at age extremes or with immunocompromising conditions. Viral causes of AGE can lead to protracted diarrheal illness in immunocompromised persons. Nucleic acid amplification tests are changing diagnostic testing algorithms.

An HIV-Positive Patient With Disseminated Histoplasmosis Complicated by Histoplasma Ileitis-Induced Small Bowel Obstruction

A 43-year-old male has a medical history of Human immunodeficiency virus (HIV) with no anti-retroviral therapy for six years prior to admission. He presented from an outside hospital with 40 lbs weight loss over one year, worsening abdominal pain, and odynophagia, with CT-confirmed small bowel obstruction (SBO) in the setting of untreated cytomegalovirus (CMV) ileitis. Treatment for both the untreated HIV and CMV ileitis was started during this hospitalization, and his hospital course was complicated by disseminated histoplasmosis in his lungs and GI tract, leading to stricture and a recurrent SBO. This case report will focus on an unusual complication of untreated HIV and a late diagnosis of histoplasmosis: Histoplasma ileitis-induced stricture and recurrent SBO. To date, there are a limited number of reports that describe gastrointestinal histoplasmosis in HIV patients, and SBO remains a rare and serious complication of disseminated histoplasmosis.

Histoplasmosis and inflammatory bowel disease: A case report

BACKGROUND

Infection with Histoplasma capsulatum can lead to a disseminated disease involving the gastrointestinal tract presenting as diffuse abdominal pain and inflammatory diarrhea which may mimic inflammatory bowel disease (IBD).

CASE SUMMARY

In the current report, we discuss the case of a 41-year old male who presented to the emergency department with complaints of high-grade intermittent fevers and severe abdominal pain with associated diarrhea and hematochezia. Laboratory results demonstrated transaminitis and elevated erythrocyte sedimentation rate, C-reactive protein and ferritin levels. The patient’s presentation was thought to be an exacerbation of his underlying IBD, but further investigations revealed a positive Histoplasma antigen in the urine. The patient was offered a colonoscopy and biopsy to confirm the diagnosis; however, he refused. He was treated with itraconazole and showed significant improvement of his symptoms, thereby confirming the diagnosis of gastrointestinal histoplasmosis.

CONCLUSION

Here within, we provide a review of IBD, evaluation of chronic diarrhea, and gastrointestinal histoplasmosis.

Treating progressive disseminated histoplasmosis in people living with HIV

BACKGROUND

Progressive disseminated histoplasmosis (PDH) is a serious fungal infection that affects people living with HIV. The best way to treat the condition is unclear.

OBJECTIVES

We assessed evidence in three areas of equipoise. 1. Induction. To compare efficacy and safety of initial therapy with liposomal amphotericin B versus initial therapy with alternative antifungals. 2. Maintenance. To compare efficacy and safety of maintenance therapy with 12 months of oral antifungal treatment with shorter durations of maintenance therapy. 3. Antiretroviral therapy (ART). To compare the outcomes of early initiation versus delayed initiation of ART.

SEARCH METHODS

We searched the Cochrane Infectious Diseases Group Specialized Register; Cochrane CENTRAL; MEDLINE (PubMed); Embase (Ovid); Science Citation Index Expanded, Conference Proceedings Citation Index-Science, and BIOSIS Previews (all three in the Web of Science); the WHO International Clinical Trials Registry Platform, ClinicalTrials.gov, and the ISRCTN registry, all up to 20 March 2020.

SELECTION CRITERIA

We evaluated studies assessing the use of liposomal amphotericin B and alternative antifungals for induction therapy; studies assessing the duration of antifungals for maintenance therapy; and studies assessing the timing of ART. We included randomized controlled trials (RCT), single-arm trials, prospective cohort studies, and single-arm cohort studies.

DATA COLLECTION AND ANALYSIS

Two review authors assessed eligibility and risk of bias, extracted data, and assessed certainty of evidence. We used the Cochrane 'Risk of bias' tool to assess risk of bias in randomized studies, and ROBINS-I tool to assess risk of bias in non-randomized studies. We summarized dichotomous outcomes using risk ratios (RRs), with 95% confidence intervals (CI).

MAIN RESULTS

We identified 17 individual studies. We judged eight studies to be at critical risk of bias, and removed these from the analysis. 1. Induction We found one RCT which compared liposomal amphotericin B to deoxycholate amphotericin B. Compared to deoxycholate amphotericin B, liposomal amphotericin B may have higher clinical success rates (RR 1.46, 95% CI 1.01 to 2.11; 1 study, 80 participants; low-certainty evidence). Compared to deoxycholate amphotericin B, liposomal amphotericin B has lower rates of nephrotoxicity (RR 0.25, 95% CI 0.09 to 0.67; 1 study, 77 participants; high-certainty evidence). We found very low-certainty evidence to inform comparisons between amphotericin B formulations and azoles for induction therapy. 2. Maintenance We found no eligible study that compared less than 12 months of oral antifungal treatment to 12 months or greater for maintenance therapy. For both induction and maintenance, fluconazole performed poorly in comparison to other azoles. 3. ART We found one study, in which one out of seven participants in the 'early' arm and none of the three participants in the 'late' arm died.

AUTHORS' CONCLUSIONS

Liposomal amphotericin B appears to be a better choice compared to deoxycholate amphotericin B for treating PDH in people with HIV; and fluconazole performed poorly compared to other azoles. Other treatment choices for induction, maintenance, and when to start ART have no evidence, or very low certainty evidence. PDH needs prospective comparative trials to help inform clinical decisions.

Advances in Understanding Human Genetic Variations That Influence Innate Immunity to Fungi

Fungi are ubiquitous. Yet, despite our frequent exposure to commensal fungi of the normal mammalian microbiota and environmental fungi, serious, systemic fungal infections are rare in the general population. Few, if any, fungi are obligate pathogens that rely on infection of mammalian hosts to complete their lifecycle; however, many fungal species are able to cause disease under select conditions. The distinction between fungal saprophyte, commensal, and pathogen is artificial and heavily determined by the ability of an individual host's immune system to limit infection. Dramatic examples of commensal fungi acting as opportunistic pathogens are seen in hosts that are immune compromised due to congenital or acquired immune deficiency. Genetic variants that lead to immunological susceptibility to fungi have long been sought and recognized. Decreased myeloperoxidase activity in neutrophils was first reported as a mechanism for susceptibility to Candida infection in 1969. The ability to detect genetic variants and mutations that lead to rare or subtle susceptibilities has improved with techniques such as single nucleotide polymorphism (SNP) microarrays, whole exome sequencing (WES), and whole genome sequencing (WGS). Still, these approaches have been limited by logistical considerations and cost, and they have been applied primarily to Mendelian impairments in anti-fungal responses. For example, loss-of-function mutations in CARD9 were discovered by studying an extended family with a history of fungal infection. While discovery of such mutations furthers the understanding of human antifungal immunity, major Mendelian susceptibility loci are unlikely to explain genetic disparities in the rate or severity of fungal infection on the population level. Recent work using unbiased techniques has revealed, for example, polygenic mechanisms contributing to candidiasis. Understanding the genetic underpinnings of susceptibility to fungal infections will be a powerful tool in the age of personalized medicine. Future application of this knowledge may enable targeted health interventions for susceptible individuals, and guide clinical decision making based on a patient's individual susceptibility profile.

The Broad Clinical Spectrum of Disseminated Histoplasmosis in HIV-Infected Patients: A 30 Years' Experience in French Guiana

Histoplasmosis is a common but neglected AIDS-defining condition in endemic areas for Histoplasma capsulatum. At the advanced stage of HIV infection, the broad spectrum of clinical features may mimic other frequent opportunistic infections such as tuberculosis and makes it difficult for clinicians to diagnose histoplasmosis in a timely manner. Diagnosis of histoplasmosis is difficult and relies on a high index of clinical suspicion along with access to medical mycology facilities with the capacity to implement conventional diagnostic methods (direct examination and culture) in a biosafety level 3 laboratory as well as indirect diagnostic methods (molecular biology, antibody, and antigen detection tools in tissue and body fluids). Time to initiation of effective antifungals has an impact on the patient's prognosis. The initiation of empirical antifungal treatment should be considered in endemic areas for Histoplasma capsulatum and HIV. Here, we report on 30 years of experience in managing HIV-associated histoplasmosis based on a synthesis of clinical findings in French Guiana with considerations regarding the difficulties in determining its differential diagnosis with other opportunistic infections.

Gastrointestinal histoplasmosis mimicking peritonitis carcinomatosis: a rare case of an emergent surgical presentation of HIV de novo

Gastrointestinal perforation due to infection, including disseminated histoplasmosis, is a rare cause of the surgical acute abdomen, especially in an apparently healthy patient. We describe a rare case of gastrointestinal histoplasmosis-induced small intestine perforation as the first manifestation of acquired immune deficiency syndrome in a healthy patient. Remarkably, the disease mimicked peritonitis carcinomatosis during explorative laparoscopy.

A case of gastrointestinal histoplasmosis with esophageal involvement

Histoplasmosis is a common infection endemic to the Ohio and Mississippi River Valleys caused by the inhalation of Histoplasma capsulatum spores from contaminated soil. Most infections are asymptomatic; however, patients with impaired cellular immunity (HIV infection, hematologic malignancy, solid organ transplant, hematopoietic stem cell transplant or TNF-⍺ inhibitor use) are at risk for disseminated disease. Disseminated histoplasmosis commonly affects the lungs, liver, spleen, bone marrow and gastrointestinal tract. Esophageal involvement is rare and usually due to extrinsic compression from affected mediastinal/hilar lymph nodes. Herein, we report a case of disseminated histoplasmosis in an AIDs patient involving the esophagus, without evidence of mediastinal involvement.

A Case of Isolated Gastrointestinal Histoplasmosis

Histoplasmosis is a self-limited and asymptomatic disease in immunocompetent individuals. Patients with untreated human immunodeficiency virus (HIV) or immune suppression due to medications such as corticosteroids can present with disseminated and life-threatening infections. We present a case of a 60-year-old female that presented with recurrent diarrhea that was found to have isolated gastrointestinal (GI) histoplasmosis. The rarity of this case is due to the isolated colonic involvement and lack of respiratory symptoms (the portal of infection). In conclusion, clinicians should be aware of isolated histoplasmosis affecting the GI tract and careful endoscopic evaluation with adequate sampling is warranted to confirm the diagnosis.

Gastrointestinal Histoplasmosis Presenting as an Acute Abdomen with Jejunal Perforation

Introduction

Gastrointestinal histoplasmosis (GH) is a well-described albeit uncommon disease. It is found almost exclusively in the immunocompromised host, especially those with untreated HIV and low CD4 counts. Presentation with intestinal perforation is seen mostly commonly in the colon. We present a patient with jejunal perforation, and there have been only 3 previous cases reported in the literature.

Case

A 39-year-old male with known, untreated HIV presented to the ED with an acute abdomen after experiencing worsening intermittent abdominal pain for 2 months before that was associated with nausea, vomiting, diarrhea, and weight loss. CT of the abdomen and pelvis revealed evidence of gas in the mesentery, small bowel thickening, edema, and free fluid in the abdomen. Emergency exploratory laparotomy was conducted. Intraoperative findings included a perforated jejunum that was studded with nodular lesions as well as mesenteric masses. Histopathologic exam of these mesenteric masses and jejunal lesions were positive for histoplasmosis.

Conclusion

Disseminated histoplasmosis is a life-threatening disease that occurs nearly exclusively in immunocompromised hosts. Untreated, mortality is as high as 80%. This rare presentation with jejunal perforation highlights the need for awareness of histoplasmosis involvement throughout the entirety of the GI tract.

Histoplasma and Cytomegalovirus Coinfection of the Gastrointestinal Tract in a Patient with AIDS: A Case Report and Review of the Literature

Opportunistic infections of the gastrointestinal tract are well-documented complications of patients with acquired immunodeficiency syndrome (AIDS). However, concomitant infection by Histoplasma and cytomegalovirus has been described rarely. We present the case of an HIV patient with a CD4 count of 20 cells/uL who was admitted with odynophagia and weight loss. Endoscopic evaluation revealed ulcerations in the esophagus and colon, and a mass formation in cecum. Histology revealed budding yeasts in the cecum and a transverse colon consistent with Histoplasma. Urine Histoplasma antigen was positive. Esophageal tissue disclosed viral cytopathic changes. Immunostaining was positive for cytomegalovirus in the esophagus and transverse colon. The patient was started on appropriate antifungal and antiviral treatment with complete resolution of his symptoms. To our knowledge, this is the fifth case of Histoplasma and cytomegalovirus co-infection of the gastrointestinal tract in a patient with AIDS. We also review the literature for similar cases in regards to clinical presentation and the type of gastrointestinal involvement.

Fatal gastrointestinal histoplasmosis 15 years after orthotopic liver transplantation

We report a case of ileo-colonic Histoplasmosis without apparent respiratory involvement in a patient who had previously undergone an orthotopic liver transplant (OLT) for primary biliary cholangitis 15 years earlier. The recipient lived in the United Kingdom, a non-endemic region for Histoplasmosis. However, she had previously lived in rural southern Africa prior to her OLT. The patient presented with iron deficiency anaemia, diarrhoea, abdominal pain and progressive weight loss. She reported no previous foreign travel, however, it later became known that following her OLT she had been on holiday to rural southern Africa. On investigation, a mild granulomatous colitis primarily affecting the right colon was identified, that initially improved with mesalazine. Her symptoms worsened after 18 mo with progressive ulceration of her distal small bowel and right colon. Mycobacterial, Yersinia, cytomegalovirus and human immunodeficiency virus infections were excluded and the patient was treated with prednisolone for a working diagnosis of Crohn’s disease. Despite some early symptom improvement following steroids, there was subsequent deterioration with the patient developing gram-negative sepsis and multi-organ failure, leading to her death. Post-mortem examination revealed that her ileo-colonic inflammation was caused by Histoplasmosis.

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.

How to Diagnose and Treat IBD Mimics in the Refractory IBD Patient Who Does Not Have IBD

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract and includes both Crohn's disease and ulcerative colitis. Patients with IBD often present with abdominal pain, diarrhea, and rectal bleeding but may also have a wide variety of other symptoms such as weight loss, fever, nausea, vomiting, and possibly obstruction. Given that the presentation of IBD is not specific, the differential diagnosis is broad and encompasses a wide spectrum of diseases, many of which can mimic and/or even coexist with IBD. It is important for physicians to differentiate symptoms due to refractory IBD from symptoms due to IBD mimics when a patient is not responding to standard IBD treatment. Many of the various IBD mimics include infectious etiologies (viral, bacterial, mycobacterial, fungal, protozoal, and helminthic infections), vascular causes, other immune causes including autoimmune etiologies, drug-induced processes, radiation-induced, and other etiologies such as small intestinal bacterial overgrowth, diverticulitis, and bile acid malabsorption. Thoughtful consideration and evaluation of these potential etiologies through patient history and physical examination, as well as appropriate tests, endoscopic evaluation, and cross-sectional imaging is required to evaluate any patient presenting with symptoms consistent with IBD.

Intestinal histoplasmosis in immunocompetent adults

AIM: To present a retrospective analysis of clinical and endoscopic features of 4 cases of immunocompetent hosts with intestinal histoplasmosis (IH).

METHODS: Four immunocompetent adults were diagnosed with IH between October 2005 and March 2015 at West China Hospital of Sichuan University. Clinical and endoscopic characteristics were summarized and analyzed retrospectively. GMS (Gomori methenamine silver), PAS (periodic acid-Schiff) and Giemsa staining technique were used to confirm Histoplasma capsulatum(H. capsulatum). The symptoms, signs, endoscopic presentations, radiographic imaging, pathological stain results and follow-up are presented as tables and illustrations.

RESULTS: The cases were male patients, ranging from 33 to 61 years old, and primarily presented with non-specific symptoms such as irregular fever, weight loss, abdominal pain and distention. Hepatosplenomegaly and lymphadenopathy were the most common signs. Endoscopic manifestations were localized or diffuse congestion, edema, ulcers, and polypoid nodules with central erosion involving the terminal ileum, ascending colon, transverse colon, descending colon, sigmoid colon and rectum, similar to intestinal tuberculosis, tumor, and inflammatory bowel disease. Numerous yeast-like pathogens testing positive for PAS and GMS stains but negative for Giemsa were detected in the cytoplasm of the histiocytes, which were highly suggestive of H. capsulatum.

CONCLUSION: Immunocompetent individuals suffering from histoplasmosis are rarely reported. It is necessary that gastroenterologists and endoscopists consider histoplasmosis as a differential diagnosis, even in immunocompetent patients.

PrimaryHistoplasma capsulatumEnterocolitis Mimicking Peptic and Inflammatory Bowel Disease

In immunocompromised patients, histoplasmosis may present as disseminated disease. We present a 52-year-old Caucasian male with symptoms of dyspepsia, postprandial epigastric pain, nausea, and nonbloody diarrhea. Upper and lower gastrointestinal endoscopies were suspicious for inflammatory bowel disease (IBD); however, biopsies were consistent with histoplasmosis, specifically in the duodenum.

Acalculous Cholecystitis Due to Histoplasma capsulatum in a Patient With HIV Infection

Although acalculous cholecystitis typically occurs in critically ill individuals, it has been described in patients with HIV infection. Recognition of AIDS-related acalculous cholecystitis is important for gastroenterologists to provide optimal therapy, since many different opportunistic pathogens may be involved. Histoplasma capsulatum causes a wide spectrum of infectious sequelae, including disseminated histoplasmosis in patients with HIV infection, but biliary tract involvement has been described infrequently. We present a case of acalculous cholecystitis caused by H. capsulatum in a patient with HIV infection.

Chronic infections of the small intestine

PURPOSE OF REVIEW

Chronic infections of the small intestine cause significant morbidity and mortality globally. This review focuses on the recent advances in the field of our understanding of selected intestinal infections.

RECENT FINDINGS

Primary and secondary immunodeficiency increase the susceptibility to many chronic intestinal infections. Endoscopy and intestinal biopsies are central to establishing a diagnosis of these conditions. Tuberculosis (TB) remains a major global health challenge. Emerging therapeutic agents to counteract multidrug-resistant strains have shown clinical efficacy, but concerns regarding mortality remain. PCR-based diagnostic TB tests have the potential to reduce diagnostic delays, but remain to be validated for intestinal infections. Adjunctive diagnostic imaging modalities can differentiate infections from Crohn's disease with increasing accuracy. Whipple's disease remains rare, but there have been substantial advances in our understanding of the causative organism Tropheryma whipplei. Extended treatment with broad-spectrum antibiotics is effective in most cases. The narrow therapeutic window and limited armamentarium for treating invasive filamentous fungal infections contribute to their significant morbidity and high rates of mortality.

SUMMARY

The speed and accuracy of diagnosing chronic intestinal infections have improved with recent imaging and laboratory methodologies. Significant research opportunities remain for clinicians and scientists to improve the diagnostic accuracy and clinical outcomes of chronic intestinal infections.

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.

Histoplasmosis as a possible cause of retroperitoneal fibrosis and median arcuate ligament syndrome: A case report

INTRODUCTION

Median arcuate ligament syndrome (MALS), a condition of poorly understood etiology, is caused by compression of the celiac artery by fibers of the median arcuate ligament.

PRESENTATION OF CASE

A 46-year-old man with chronic abdominal pain and weight loss was diagnosed with MALS and admitted for surgery. During surgery, extensive retroperitoneal fibrosis around the celiac artery and adjacent aorta was noted. Large necrotizing granulomas and budding yeast, both indicators of histoplasmosis, were found on pathologic evaluation of retroperitoneal tissue removed during surgery.

DISCUSSION

Histoplasma capsulatum may cause pulmonary fibrosis and fibrosing mediastinitis, and the organism may disseminate to reach various internal organs in the immunocompromised individual. Retroperitoneal histoplasmosis has been demonstrated in immunocompromised individuals in the past without retroperitoneal fibrosis. Our patient may have had chronic histoplasma infection of his retroperitoneal lymph nodes, triggering fibrosis in the area surrounding the adjacent celiac artery and abdominal aorta, thus leading to symptomatic MALS.

CONCLUSION

Histoplasma capsulatum, an organism that has demonstrated its capability to cause fibrosis elsewhere in the body, may play a causative role in MALS in our patient, given the finding of retroperitoneal fibrosis in conjunction with retroperitoneal lymph node histoplasma.

Progressive disseminated histoplasmosis in the HIV population in Europe in the HAART era. Case report and literature review

INTRODUCTION

In highly endemic areas, up to 20 % of human immunodeficiency virus (HIV)-infected persons will develop progressive disseminated histoplasmosis (PDH). Europe is not endemic to histoplasmosis, and the disease is mainly found in immigrants often co-infected with HIV.

METHODS

We present a case of a patient with HIV and PDH highlighting the possible diagnostic difficulties that may arise in a non-endemic area and review the literature of histoplasmosis in the context of HIV infection with special focus on Europe.

DISCUSSION

When cellular immunity wanes (usually at CD4 T-lymphocyte counts <150 cells/μL) histoplasma infection, acquired earlier, can reactivate and disseminate. PDH is an acquired immune deficiency syndrome(AIDS)-defining disease and a life-threatening infection, with a clinical spectrum ranging from an acute, fatal course with lung infiltrates and respiratory failure, shock, coagulopathy and multi-organ failure, to a more subacute disease with focal organ involvement, pancytopenia and hepatosplenomegaly. Mortality rates remain high for untreated patients, but early diagnosis, proper antifungal treatment and early initiation of antiretroviral therapy have improved the prognosis.

CONCLUSION

European infectious diseases physicians, microbiologists and pathologists must be aware of histoplasmosis, particularly when facing HIV-infected immigrants from endemic areas. This is increasingly important due to migration and travel activities from these areas.

Colonic involvement in disseminated histoplasmosis of an immunocompetent adult: case report and literature review

BACKGROUND

Histoplasmosis is a common opportunistic fungal infection that is observed almost exclusively in immunodeficient patients, especially those with AIDS. Immunocompetent individuals that suffer from histoplasmosis are rarely reported, especially those with disseminated lesions, such as disseminated histoplasmosis. The observation of disseminated histoplasmosis with prominent gastrointestinal involvement, no respiratory symptoms (which is presumed to be the portal of infection), gastrointestinal pathological changes, and minor digestive system disorders make this case study exceedingly rare.

CASE PRESENTATION

We report the case of a 33-year-old immunocompetent male who presented with fever and weight loss. Based on investigations, the patient showed pancytopenia, hepatosplenomegaly, bone marrow involvement and marked colonic involvement. Finally, disseminated histoplasmosis was diagnosed and confirmed by stained smears of fine needle aspirates and biopsy from lesions in the bone marrow and colon. The patient showed appreciable regression of lesions following prompt treatment with amphotericin B deoxycholate, and was treated thereafter with oral itraconazole following discharge from hospital.

CONCLUSION

Disseminated histoplasmosis could be underestimated in immunocompetent patients. A high degree of clinical suspicion is essential in both immunocompromised and immunocompetent patients, regardless of pulmonary symptoms, and whether in endemic or non-endemic areas. Early and accurate diagnosis is extremely important for the appropriate treatment of infection and to improve disease outcome.

Colonic involvement in disseminated histoplasmosis of an immunocompetent adult: case report and literature review

BACKGROUND

Histoplasmosis is a common opportunistic fungal infection that is observed almost exclusively in immunodeficient patients, especially those with AIDS. Immunocompetent individuals that suffer from histoplasmosis are rarely reported, especially those with disseminated lesions, such as disseminated histoplasmosis. The observation of disseminated histoplasmosis with prominent gastrointestinal involvement, no respiratory symptoms (which is presumed to be the portal of infection), gastrointestinal pathological changes, and minor digestive system disorders make this case study exceedingly rare.

CASE PRESENTATION

We report the case of a 33-year-old immunocompetent male who presented with fever and weight loss. Based on investigations, the patient showed pancytopenia, hepatosplenomegaly, bone marrow involvement and marked colonic involvement. Finally, disseminated histoplasmosis was diagnosed and confirmed by stained smears of fine needle aspirates and biopsy from lesions in the bone marrow and colon. The patient showed appreciable regression of lesions following prompt treatment with amphotericin B deoxycholate, and was treated thereafter with oral itraconazole following discharge from hospital.

CONCLUSION

Disseminated histoplasmosis could be underestimated in immunocompetent patients. A high degree of clinical suspicion is essential in both immunocompromised and immunocompetent patients, regardless of pulmonary symptoms, and whether in endemic or non-endemic areas. Early and accurate diagnosis is extremely important for the appropriate treatment of infection and to improve disease outcome.

Duodenal histoplasmosis presenting with upper gastrointestinal bleeding in an AIDS patient

Gastrointestinal histoplasmosis (GIH) is common in patients with disseminated disease but only rarely comes to clinical attention due to the lack of specific signs and symptoms. We report the unusual case of a 33-year-old Caucasian male with advanced AIDS who presented with upper GI bleeding from diffuse erosions throughout the duodenum. Biopsy of the lesions revealed small bowel mucosa with granulomatous inflammation and macrophages with small intracellular yeasts consistent with disseminated histoplasmosis. The patient demonstrated significant clinical improvement following a two-week course of liposomal amphotericin B. To our knowledge, this is the first case report of duodenal histoplasmosis leading to clinically significant bleeding, manifesting with worsening anemia and melanotic stools. Given our findings, we maintain that GIH should be considered on the differential diagnosis for GI bleeding in AIDS patients at risk, specifically those with advanced immunosuppression (i.e., CD4⁺ cell counts <100 cells/mm³) who reside in endemic areas (Ohio or Mississippi river valleys) and/or have a prior history of histoplasmosis. For diagnostic evaluation, we recommend checking a urine Histoplasma quantitative antigen EIA as well as upper and/or lower endoscopy with biopsy. We recommend treatment with a two-week course of liposomal amphotericin B followed by indefinite itraconazole.

Diarrhea in the immunocompromised patient

Diarrhea is a common problem in patients with immunocompromising conditions. The etiologic spectrum differs from patients with diarrhea who have a normal immune system. This article reviews the most important causes of diarrhea in immunocompromised patients, ranging from infectious causes to noninfectious causes of diarrhea in the setting of HIV infection as a model for other conditions of immunosuppression. It also deals with diarrhea in specific situations, eg, after hematopoietic stem cell or solid organ transplantation, diarrhea induced by immunosuppressive drugs, and diarrhea in congenital immunodeficiency syndromes.

Dimorphic fungal coinfection as a cause of chronic diarrhea and pancolitis

Histoplasma capsulatum and Paracoccidioides brasiliensis are dimorphic fungi that cause systemic mycosis mostly in tropical South America and some areas of North America. Gastrointestinal involvement is not uncommon among these fungal diseases, but coinfection has not previously been reported. We report a patient with chronic diarrhea and pancolitis caused by paracoccidioidomycosis and histoplasmosis.

An Apple-core Lesion in the Colon: An Infectious Etiology

Gastrointestinal involvement occurs in about 70% to 90% of histoplasmosis cases but is usually not the initial manifestation. We present the case of a 52-yearold HIV-positive woman who presented with gastrointestinal symptoms and an apple-core lesion on CT scan of the abdomen. The patient had been diagnosed with histoplasma colitis eight months earlier and was started on long-term itraconazole therapy. However, she prematurely discontinued treatment. A colonoscopy during the present hospitalization revealed a 3.5-cm mass, biopsies of which revealed Histoplasma capsulatum. In the present report, we discuss the differential diagnosis of apple-core lesions in the colon and the importance of keeping histoplasmosis on the differential diagnosis, especially in endemic areas like the Ohio River valley. It is equally important to ensure compliance with treatment of histoplasmosis, as well as close follow-up, as progression to colonic obstruction while on medical management has been reported.

[Imported histoplasmosis in Navarra: presentation of four cases]

OBJECTIVE

Histoplasmosis is a fungal infection caused by the dimorphic fungi Histoplasma capsulatum. Its incidence in Spain has increased in recent years, mainly due to the increased presence of immigrants from Latin America and increased travel to the continent for tourism and cooperation. Our aim was to review the clinical characteristics of cases of histoplasmosis diagnosed in our hospital during the last six years.

CASE REPORTS

We diagnosed 4 cases from 4 patients from South America, 3 of whom were HIV positive and 1 diagnosed with dermatomyositis was treated with immunosuppressive drugs. The laboratory diagnosis was carried out by histological and microbiological study, by culture and specific PCR directly on the sample.

DISCUSSION

As it is an imported infection there needs to be a high level of suspicion and a detailed history taken to get a diagnosis. This infection requires a differential diagnosis between febrile syndrome in immunosuppressed patients, both HIV positive and immunosuppressive therapy, which originate from endemic areas, or who have a history of staying in them.

Oropharyngeal histoplasmosis: report of eleven cases and review of the literature

INTRODUCTION: Histoplasmosis is a systemic mycosis endemic in Brazil, especially in the State of Rio Grande do Sul, where Histoplasma capsulatum was isolated from the soil. H. capsulatum may compromise unusual areas, including the oropharynx, particularly in patients presenting disseminated histoplasmosis; which is associated with a state of immunosuppression, such as AIDS. METHODS: During database analysis of a total of 265 cases of histoplasmosis, the medical records of 11 patients with histological or microbiological diagnoses of oral histoplasmosis (OH) between 1987 and 2008 were retrospectively reviewed. RESULTS: This work reports 11 cases of OH, the majority presenting histopathological or microbiological evidence of disseminated histoplasmosis (DH). In the patients with DH, OH was the first manifestation of histoplasmosis. Five of the 11 patients discussed were HIV-seropositive with clinical and laboratory findings of AIDS. Four patients presented active pulmonary tuberculosis concomitant with histoplasmosis. Treatment was based on the use of itraconazole and amphotericin B deoxycholate. Eight patients responded successfully to therapy after one year, two did not come back for reevaluation and one died despite adequate therapy. CONCLUSIONS: Oral histoplasmosis is closely associated with immunosuppression status, especially in patients presenting AIDS; moreover, in many cases, OH is the first sign of disseminated histoplasmosis.

Concurrent amoebic and histoplasma colitis: A rare cause of massive lower gastrointestinal bleeding

Infective colitis can be a cause of massive lower gastrointestinal bleeding requiring acute surgical intervention. Causative organisms include entamoeba and histoplasma species. However, concurrent colonic infection with both these organisms is very rare, and the in vivo consequences are not known. A 58-year-old male presented initially to the physicians with pyrexia of unknown origin and bloody diarrhea. Amoebic colitis was diagnosed based on biopsies, and he was treated with metronidazole. Five days later, the patient developed massive lower gastrointestinal bleeding with hemorrhagic shock. Emergency total colectomy with end-ileostomy was performed. However, he deteriorated and died on the second postoperative day. Histopathological examination revealed multiple deep ulcers at the hepatic flexure where fungal bodies of mycelial and yeast forms were noted. Isolated lymph nodes showed abscess formation with fungal bodies. Infective fungal colitis with Histoplasma capsilatum was diagnosed. In vitro, amoebic parasites can increase virulence and pathogenicity of histoplasma which may account for the fulminant presentation in this patient. Although rare, this unusual dual infection should be considered in the differential diagnosis of infective colitis, as appropriate antimicrobial treatment may prevent progression to massive lower gastrointestinal bleeding, obviating the need for urgent surgical intervention.

Recurrent histoplasmosis in AIDS mimicking a colonic carcinoma

The prevalence rate of lower gastrointestinal bleeding in patients with AIDS is around 2.6%. A 42-year-old woman with AIDS (CD(4) count 9/microL) and recently treated for disseminated histoplasmosis presented to the emergency room with melena, severe anaemia and fever. A colonoscopy showed an umbilicated colonic nodule mimicking a carcinoma of the colon. The biopsy showed intracytoplasmic microorganisms compatible with Histoplasma capsulatum. She had poor compliance to the itraconazole when discharge on previous admission. Despite the fact that colonic histoplasmosis is uncommon, the mortality rate is around 8% and clinicians should be aware of the clinical presentation of histoplasmosis when recur, especially in patients not taking the itraconazole for long-term treatment.

Gastrointestinal histoplasmosis in an HIV-infected patient living in a non-endemic area

SUMMARY

A 36-year-old HIV-infected man presented with non-specific gastrointestinal symptoms and weight loss. Biopsy of the duodenum and an intra-abdominal lymph node showed Histoplasma capsulatum. The diagnosis of histoplasmosis was delayed as the presentation was initially ascribed to intercurrent enteric pathogens and the patient's lifetime travel history was not obtained.

[Bacterial, mycobacterial and fungal opportunistic infections in HIV-infected immigrants: diagnosis and treatment]

The number of HIV infected immigrants has increased sharply in Spain. These patients are prone to contracting several different types of opportunistic infections, including bacterial, mycobacterial, fungal and parasitic infections. The present article provides an in-depth review of bacterial and fungal infections, with particular emphasis on those not endemic in our country.