Disseminated histoplasmosis mimicking metastatic disease of the colon and omentum: Report of a case and literature review

Adrenal Histoplasmosis and Tuberculosis: Clinical Presentations and a High Prevalence of Adrenal Insufficiency

OBJECTIVE

Adrenal infections can lead to adrenal insufficiency (AI). Commonly reported pathogens are Histoplasma capsulatum and Mycobacterium tuberculosis (TB), which can cause similar clinical presentations, yet require different specific treatments. We aim to evaluate clinical presentations, imaging characteristics, and AI prevalence in adrenal infections caused by these pathogens.

DESIGNS

Retrospective study.

PATIENTS

Thirty-five patients with microbiologically confirmed adrenal histoplasmosis and TB at two referral centers in Bangkok, Thailand.

RESULTS

Thirty-one patients (88.5%) had adrenal histoplasmosis, 3 (8.5%) had adrenal TB, and 1 (3.0%) had coinfection. Most patients were non-HIV (97%) males (91%), with a mean age of 64 years. Common symptoms were anorexia and weight loss (91%), with 26% presenting with adrenal crisis. Extra-adrenal infections occurred in 45% of histoplasmosis, 67% of TB, and 100% of coinfections, with 10% of adrenal histoplasmosis patients having concurrent extra-adrenal TB infection. Bilateral adrenal abnormalities were seen in 91%, and all patients with unilateral lesions later developed contralateral involvement. Adrenal lesions ranged from enlargement to mass sized 9.8 cm. The prevalence of AI was 74% (histoplasmosis 73%, TB and coinfection 100%). Over a median follow-up of 22 months, all patients with AI remained on glucocorticoid supplements.

CONCLUSION

Adrenal histoplasmosis and TB primarily affected non-HIV males. Most patients presented with bilateral adrenal masses. The prevalence of AI was high and likely persistent despite specific treatment. Extra-adrenal infections were common in TB and coinfection but were insufficient to determine adrenal infection etiology, highlighting the need for tissue diagnosis.

Disseminated histoplasmosis: Long journey of a febrile young man

A 19-year-old non-diabetic, non-HIV male presented with eighteen months of fever, weight loss, skin rash and lymphadenopathy. He was treated with anti-tubercular medication for more than twelve months in multiple institutions based on repeated biopsy reports of lymph nodes showing granuloma suggestive of tuberculosis. Before he was diagnosed at Bangabandhu Sheikh Mujib Medical University (BSMMU) with disseminated histoplasmosis at eighteen months of his disease, he already lost twenty kg weight, developed multiple small joint pain, back pain, and cough along with previously mentioned symptoms. Extensive investigations at BSMMU revealed biopsy material from multiple sites showed noncaseating granulomas with Periodic acid-Schiff (PAS) stain positive for budding oval yeast cells, and fungal culture revealed growth of dimorphic fungus suggestive of Histoplasma after three weeks. After treatment with intravenous liposomal amphotericin B with continuous itraconazole, the patient's fever completely subsided, his well-being improved, joint pain reduced, started to gain weight, and skin lesions started to heal. This case serves as a significant reminder that it is imperative to consider alternative diagnoses in patients who fail to show improvement with conventional antitubercular treatment.

Gastrointestinal Bleeding and Hemorrhagic Shock in a Patient Diagnosed With Disseminated Histoplasmosis

A 63-year-old patient with HIV/AIDS and hepatitis B virus was found to have disseminated histoplasmosis with gastrointestinal bleeding. The patient was initially treated for sepsis, but the infectious workup was negative. Computed tomography of the abdomen and pelvis showed diffuse mesenteric and retroperitoneal lymphadenopathy, with plan for biopsy. Unfortunately, the patient had a Code Blue after having profuse hematochezia. Esophagogastroduodenoscopy disclosed actively bleeding duodenal ulcer; computed tomography angiography showed gastric and jejunal extravasation. The patient expired, and autopsy revealed histoplasmosis of duodenum and jejunum. Esophagogastroduodenoscopy is particularly helpful for timely diagnosis in immunocompromised patients with gastrointestinal bleed from suspected infections or malignancy.

Gastrointestinal Histoplasmosis Mimicking Crohn's Disease

Disseminated histoplasmosis is a life-threatening disease usually seen in immunocompromised patients living in endemic areas. We present an apparently immunocompetent patient with gastrointestinal histoplasmosis who was initially diagnosed with biopsy-proven Crohn's disease. Following discontinuation of anti-inflammatory drugs and institution of antifungal therapy, his gastrointestinal illness completely improved. Specific fungal staining should be routinely included in histopathologic assessment of tissue specimens diagnosed as Crohn's disease.

Lower Gastrointestinal Bleeding Secondary to Intestinal Histoplasmosis in a Renal Transplant Patient

Histoplasmosis is the most common endemic mycosis in the United States. Symptomatic gastrointestinal histoplasmosis is a rare entity. We report a case of isolated intestinal histoplasmosis that manifested as severe lower gastrointestinal bleeding in a renal transplant patient. The patient developed hematochezia, and colonoscopy showed diffuse, extensive areas of cratered, ulcerated mucosa in the entire colon. Biopsy showed prominent mucosal and submucosal infiltrate of plump histiocytes containing intracytoplasmic yeast forms morphologically compatible with florid histoplasmosis.

Gastrointestinal Histoplasmosis: A Case Series

Histoplasmosis is an invasive mycosis caused by inhalation of the spores of dimorphic fungi Histoplasma capsulatum. The disease manifests in the lung as acute or chronic pulmonary histoplasmosis and in severe cases gets disseminated in multiple organs like skin, adrenal gland, central nervous system, lymph node, liver, spleen, bone marrow, and gastrointestinal tract. It occurs most commonly in immunodeficient patients like HIV-positive patients and transplant recipients, while immunocompetent hosts are affected rarely. In cases of gastrointestinal histoplasmosis, the samples are collected for culture and biopsy should be sent for histopathological examination for definitive diagnosis. We conducted a retrospective study of colonic biopsies performed in the department of gastroenterology in a tertiary care hospital of north India from January 2014 to December 2015. Five cases of colonic histoplasmosis were diagnosed on histopathology out of which 4 patients were from north India while 1 patient was from Myanmar. The patients presented with various complaints, including loose stools, diarrhea, altered bowel habits, and gastrointestinal bleeding. The prognosis is very good after early and aggressive treatment while the disease is fatal if it remains untreated. In our study, 2 patients died within few days of diagnosis due to delay in the diagnosis, dissemination, and associated complications. Other patients were started on amphotericin B deoxycholate and are under follow-up. An early diagnosis of gastrointestinal histoplasmosis is important as appropriate treatment leads to long-term survival while untreated cases are almost fatal.