B72-15 Disseminated Histoplasmosis Mimicking Tuberculosis and Lymphoma in an Aids Patient: The Importance of Early Antigen Recognition

Abstract Background Disseminated histoplasmosis is a life-threatening opportunistic infection in patients with advanced AIDS. Its presentation often overlaps with tuberculosis or lymphoma, leading to unnecessary isolation, invasive procedures, and treatment delays. Although Histoplasma capsulatum is endemic in the Caribbean, such cases may be underrecognized when patients present in non-endemic regions like New York. Case A 37-year-old woman with advanced HIV (CD4 16) and inconsistent antiretroviral adherence presented with fever, diarrhea, dyspnea, and profound weakness. She had recently been hospitalized elsewhere, where she was evaluated for tuberculosis and lymphoma. That work-up revealed negative AFB smears, negative MTB PCR, and a positive urine Histoplasma antigen (>15 ng/mL). During that admission, an image-guided lymph-node biopsy was attempted for diffuse lymphadenopathy to evaluate for lymphoma but was aborted due to pain. In the current presentation, she had sepsis, pancytopenia, hepatosplenomegaly, and respiratory failure. She was started on amphotericin B along with broad-spectrum antimicrobials. Despite supportive care and multiple specialty consultations, she developed multiorgan failure and disseminated intravascular coagulation requiring intubation and vasopressors. She suffered cardiac arrest and died, with disseminated histoplasmosis confirmed as the principal diagnosis. Discussion Disseminated histoplasmosis in AIDS can mimic tuberculosis and lymphoma both clinically and radiographically. Early recognition and prompt interpretation of positive antigen results can prevent unnecessary invasive procedures and delays in antifungal therapy. Conclusion Clinicians should maintain a high index of suspicion for disseminated histoplasmosis in immunocompromised patients from endemic areas presenting in non-endemic settings and promptly initiate antifungal therapy when antigen positivity supports the diagnosis. This abstract is funded by: None