Colonic histoplasmosis in AIDS: unusual endoscopic findings in two cases

[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.

Disseminated histoplasmosis in a liver transplant recipient

A 61-yr-old liver transplant recipient presented with abdominal cramping and nonbloody diarrhea resulting in orthostasis. Multiple ulcerations throughout the colon were seen during endoscopy, and biopsies from the ulcer edges revealed histoplasmosis. Treatment with a course of itraconazole improved the diarrhea. The patient later presented with pericarditis and symptomatic pleural effusions, the latter of which was confirmed to be a result of disseminated histoplasmosis. Treatment with amphotericin B led to resolution. Histoplasmosis should be considered in liver transplant patients with diarrhea and large ulcers in the colon. The presence of disseminated histoplasmosis should be ruled out once colonic histoplasmosis has been diagnosed.

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

No large case series of gastrointestinal histoplasmosis (GIH) in patients with AIDS has been published. We report 18 cases and review 34 published cases in the medical literature. We did a retrospective chart review from patients seen in our medical practices between 1989 and 2004. Most of our patients were men who had sex with men and who were not receiving highly active antiretroviral therapy. Median CD4 count was 34/muL. The most common presenting symptoms were diarrhea, fever, abdominal pain, and weight loss. The most commonly involved site was the colon or cecum. Biopsies revealed visible Histoplasma capsulatum organisms in 89%. Cultures from any site were positive in 76.9%. Four patients died from GIH. Gastrointestinal histoplasmosis occurs in severely immunocompromised patients with AIDS not receiving highly active antiretroviral therapy. Typical manifestations include diarrhea, fever, abdominal pain, and weight loss. Diagnosis is confirmed by blood or gastrointestinal tissue culture. Improvements in antiretroviral and antifungal therapies appear to have reduced the incidence of GIH and may improve the prognosis of this disease.

Gastrointestinal histoplasmosis

Gastrointestinal histoplasmosis (GIH) is an uncommon disease with protean manifestations. It may occur as a result of mediastinal histoplasmosis or in the setting of progressive dissemination. GIH may be misdiagnosed as inflammatory bowel disease, malignancy, or other intestinal diseases leading to inappropriate therapies and unnecessary surgical interventions. Patients with bowel obstruction, perforation, or bleeding, and systemic findings suggestive of histoplasmosis should be evaluated for GIH. This is especially true for immunosuppressed patients, especially those with AIDS. Diagnosis first requires consideration of histoplasmosis in the differential in patients with the above types of gastrointestinal abnormalities, and second, familiarity with a battery of mycologic and serologic tests. Progressive disseminated histoplasmosis (PDH) is lethal if left untreated, and treatment is highly effective. This review will focus on the clinical and histopathologic features of GIH, the approach to diagnosis, and recommendations for treatment.

Colonic histoplasmosis in acquired immunodeficiency syndrome mimicking carcinoma

Four cases of colonic histoplasmosis in patients with acquired immunodeficiency syndrome mimicking other diseases, primarily colonic adenocarcinoma, are presented. This topic has been extensively discussed from the medical and radiologic standpoint, but very few publications are found in the pathology literature. Emphasis is made on the discussion of the clinical manifestations; endoscopic, radiologic, and pathologic characteristics; differential diagnosis; and treatment.

Gastrointestinal histoplasmosis in patients with AIDS: case report and review

Histoplasmosis is the most common endemic mycosis in individuals with AIDS, occurring in 2%-5% of this population. Infection is more likely to be disseminated than in immunocompetent individuals and generally presents insidiously with nonspecific symptoms. The gastrointestinal tract is involved in 70%-90% of cases of disseminated histoplasmosis, yet gastrointestinal histoplasmosis per se is infrequently encountered in patients with AIDS. The diagnosis of gastrointestinal histoplasmosis is often not suspected, particularly in areas of nonendemicity, and a delay in diagnosis may lead to increased morbidity and risk of death. Since antifungal therapy improves outcome for >80% of AIDS patients with histoplasmosis, it is essential that caregivers be aware of the varied presentations of gastrointestinal histoplasmosis in order to diagnose and to treat this potentially life-threatening infection effectively.

Diagnosis and treatment of colonic disease in AIDS

The colon is a frequent site of gastrointestinal complications in patients with HIV infection, and these colonic disorders increase in frequency as immunodeficiency worsens. The most common clinical manifestations of colonic disease in AIDS are diarrhea, lower gastrointestinal bleeding, and abdominal pain. Toxic megacolon, intussuseption, typhlitis, idiopathic colonic ulcer, and pneumatosis intestinalis also have been described. In the HIV-infected patient with preserved immunity, the most common cause of colitis is bacterial, but as the degree of immunodeficiency worsens, opportunistic pathogens (CMV, protozoa, mycobacteria, fungi) and neoplasms become more frequent. The frequent use of antibiotics, chemotherapeutic agents, and frequent hospitalization increase the susceptibility to cf2Clostridium difficule cf1colitis. Endoscopy plays an integral role in the management of many colonic disorders in AIDS.