B72-12 Crohn’s, Bones, and Histoplasma Overtones: Hemophagocytic Lymphohistiocytosis Secondary to Disseminated Histoplasmosis Related to Infliximab Therapy for Crohn’s Disease

Abstract Anti-TNF therapy with an agent like infliximab is the first-line recommended therapy, often in conjunction with immunomodulating agents like thiopurines, for induction and maintenance of remission in moderate-severe Crohn’s disease. A known risk of these agents is immunosuppression, exposing patients to the risk of infection. In this case, we present a 36-year-old woman with a past medical history of ileocolic Crohn’s disease on infliximab who presented with new transaminase elevation, hyperbilirubinemia, and 2 months of fever. A new diagnosis of primary sclerosing cholangitis was made, though innumerable lung nodules, hepatomegaly, 20-lb weight loss, and chronic fevers raised concern for malignancy or fungal infection. Extensive studies, including bone marrow biopsy, urine Histoplasma antigen, and blood Histoplasma Galactomannan antigen corroborated the diagnosis of disseminated histoplasmosis. Labs and bone marrow biopsy also confirmed the diagnosis of latent EBV, and more concerningly hemophagocytic lymphohistiocytosis (HLH), likely secondary to the severe histoplasma infection. Ultimately, due to concern for worsening histoplasmosis and active HLH, the decision was made to treat with a combination of liposomal amphotericin B, posaconazole, and anakinra rather than corticosteroids. Fevers subsided, and the patient rapidly improved, soon after going home to complete the antifungal + anakinra course and later resume immunosuppression outpatient to keep her Crohn’s disease in remission. Recent literature review demonstrates that the incidence of disseminated histoplasmosis is becoming more clearly demonstrated in IBD patients on anti-TNF therapy. HLH is rare in this population, but it almost always occurs in the setting of concomitant infection. Though the symptoms and history the patient presented with are concerning for malignancy, it is crucial to consider opportunistic infection when a patient is on immunosuppressive therapy. Discussion of this case is meant to demonstrate the risk immunosuppressed IBD is associated with, share the workup, management, and resolution of an unusual case, and to continue the conversation of key considerations when caring for a severely ill, immunosuppressed patient. This abstract is funded by: None