A rare case of Disseminated Histoplasmosis with Hemophagocytic Lymphohistiocytosis mimicking a flare of Systemic Lupus Erythematosus in a middle-aged man: A Case Report

Abstract

Abstract Introduction/Objective Disseminated histoplasmosis is a progressive granulomatous disease caused by Histoplasmosis capsulatum which is an intracellular dimorphic fungus endemic to Ohio and Mississippi River valleys in the United States. The progressive spread of the infection to organs is thought to be due to the failure of the activation of the T-cell mediated immune response. Hemophagocytic lymphohistiocytosis is a rare but potentially fatal condition in which histiocytes and lymphocytes build up in and damage organs and other blood cells. Diagnosing Disseminated Histoplasmosis with Hemophagocytic Lymphohistiocytosis in a patient with Systemic Lupus Erythematosus is diagnostically challenging due to the rare presentation. Hence, we are reporting this case to alert physicians to keep a high index of suspicion in such presentations. Methods/Case Report We present a 37-year-old man with a past medical history of Systemic Lupus Erythematosus complicated by Lupus Nephritis on immunosuppressive therapy who presented to the emergency department with hypotension and was admitted for acute kidney injury. Prior to the presentation, he had persistent fever, myalgias, cough, mild shortness of breath, and back pain. CT Chest shows “eggshell” calcification and further parasitology evaluation revealed a diagnosis of histoplasmosis using a blood sample where intracellular Histoplasma organisms were identified. A diagnosis of Hemophagocytic lymphohistiocytosis was made clinically after “Clinical and Testing Criteria” was evaluated. Despite further management, he developed coagulopathy and sepsis which led to his death. Results (if a Case Study enter NA) At autopsy, we found organomegaly of the liver, spleen, and kidneys. Microscopically, these enlarged organs show old fibrotic granulomas and granulomatous inflammation with suspected fungal organisms. Periodic Acid Schiff (Fungus) and Gomori's Methenamine Silver special stain confirm these fungal organisms to be consistent with Histoplasma species (3-5 micron budding yeasts). Conclusion This case report highlights that physicians should be aware of the diagnostic challenge that Disseminated Histoplasmosis with Hemophagocytic Lymphohistiocytosis could pose in patients with Systemic Lupus Erythematosus, especially those on immunosuppression. The clinical presentation could easily mimic a flare of Systemic Lupus Erythematosus, leading to more aggressive immunosuppression. Failure to recognize the infection promptly could lead to grievous complications and sometimes death.