Gastrointestinal Histoplasmosis Mimicking Crohn's Disease

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.

Disseminated Histoplasmosis Presenting as Obstructive Jaundice

Gastrointestinal manifestations in systemic fungal infection are not uncommon; however, obstructive jaundice due to lymphadenopathy is considered rare. We present a case of a 16-year-old male patient who presented with painless jaundice. Laboratory tests revealed direct hyperbilirubinemia with cholestatic liver injury. Chest and abdominal computed tomography showed mediastinal and porta hepatis lymphadenopathy, with severe biliary ductal dilatation proximal to an obstructing lymph node near the head of the pancreas. Endoscopic ultrasound showed a 22 × 35-mm lymph node with a mass effect on the common bile duct leading to obstructive jaundice. Infectious workup confirmed the diagnosis of disseminated histoplasmosis.

Gastrointestinal Histoplasmosis: A Descriptive Review, 2001-2021

Gastrointestinal histoplasmosis (GIH) is infrequently described in people without underlying HIV infection. We aimed to compare the clinical presentation of GIH in people with and without HIV infection. We conducted a literature search of published cases of GIH from 2001-2021 and found 212 cases. Of these, 142 (67.0%) were male, and 124 (58.5%) had HIV infection. Most cases were from North America (n = 88, 41.5%) and South America (n = 79, 37.3%). Of the 212 cases, 123 (58.0%) were included in both clinical and pathological analyses. The remainder were excluded as details about clinical and pathological findings were not available. Of the 123 cases, 41 had HIV infection while 82 were without HIV infection. The diagnosis was predominantly by histopathology (n = 109, 88.6%). A significant proportion of people with HIV infection had abdominal pain as the most predominant symptom of GIH compared to those without HIV infection (65.9% versus 41.9%, p < 0.05). The colon was the most affected site with a slightly higher proportion in those with HIV infection compared with cases without HIV infection (46.3% versus 42.7%). The commonest pathologic findings were caecal and ileal ulcers. Caecal ulcers were significantly more frequent in cases with HIV infection compared to those without HIV (32.1% versus 7.1%, p < 0.05). Despite being more common in people with HIV infection, GIH also affects people without HIV infection with similar clinical presentations.

Gastrointestinal histoplasmosis complicating pediatric Crohn disease: A case report and review of literature

BACKGROUND

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

CASE SUMMARY

We report a case of 12-year-old boy with presumptive diagnosis of Crohn disease (CD) that presented with several months of abdominal pain, weight loss and bloody diarrhea. Colonoscopy showed patchy moderate inflammation characterized by erythema and numerous pseudopolyps involving the terminal ileum, cecum, and ascending colon. Histologic sections from the colon biopsy revealed diffuse cellular infiltrate within the lamina propria with scattered histiocytic aggregates, and occasional non-necrotizing granulomas. Grocott-Gomori’s Methenamine Silver staining confirmed the presence of numerous yeast forms suggestive of Histoplasma spp., further confirmed with positive urine Histoplasma antigen (6.58 ng/mL, range 0.2-20 ng/mL) and serum immunoglobulin G antibodies to Histoplasma (35.9 EU, range 10.0-80.0 EU). Intravenous amphotericin was administered then transitioned to oral itraconazole. Follow-up computed tomography imaging showed a left lower lung nodule and mesenteric lymphadenopathy consistent with disseminated histoplasmosis infection.

CONCLUSION

Gastrointestinal involvement with H. capsulatum with no accompanying respiratory symptoms is exceedingly rare and recognition is often delayed due to the overlapping clinical manifestations of IBD. This case illustrates the importance of excluding infectious etiologies in patients with “biopsy-proven” CD prior to initiating immunosuppressive therapies. Communication between clinicians and pathologists is crucial as blood cultures and antigen testing are key studies that should be performed in all suspected cases of histoplasmosis to avoid misdiagnosis and inappropriate treatment.