Kidney Week

Abstract: SA-PO1152

False Reassurance: Disseminated Histoplasmosis Diagnosed Through Transplant Allograft Biopsy

Session Information

• Transplantation: Clinical - Infectious Diseases
  October 24, 2026 | Location: Exhibit Hall A, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Transplantation

• 2002 Transplantation: Clinical

Authors

• Caceres Alan, Ariadnna, Hennepin Healthcare System Inc Department of Medicine, Minneapolis, Minnesota, United States

Ariadnna Caceres Alan, MD

• Hellerstedt, Sage T., Hennepin Healthcare System Inc Department of Medicine, Minneapolis, Minnesota, United States

Sage T. Hellerstedt, MD, MPH

• Mehmood, Tahir, Hennepin Healthcare System Inc Department of Medicine, Minneapolis, Minnesota, United States

Tahir Mehmood, MD

• Maripuri, Saugar, Hennepin Healthcare System Inc Department of Medicine, Minneapolis, Minnesota, United States

Saugar Maripuri, MD, MPH

• Dvanajscak, Zeljko, Hennepin Healthcare System Inc Department of Medicine, Minneapolis, Minnesota, United States

Zeljko Dvanajscak, MD, MS

• Jabban, Yazan, Hennepin Healthcare System Inc Department of Medicine, Minneapolis, Minnesota, United States

Yazan Jabban, MD

Introduction

Histoplasma Capsulatum is a dimorphic fungus endemic to the Ohio and Mississippi River valleys, infection is typically acquired via inhalation of mycelia in soil with avian/bat droppings. Histoplasmosis in transplant recipients can result from a primary infection, reactivation of previous infection, or rarely, transmitted via an infected allograft. Infection usually occurs within the first year post-transplant. Hematogenous dissemination develops H. capsulatum-containing granulomas in multiple organs.

Case Description

68-year-old male with deceased donor kidney transplant in 1997 due to MPGN on MMF and prednisone. History notable for CKD3b and EBV viremia. He lives on a farm in Minnesota. Work-up notable for renal dysfunction, pancytopenia, persistent fevers, confusion, and new lung nodules. Initial urine antigen for histoplasma was negative. Baseline serum creatinine 1.5mg/dL, on admission 3.3mg/dL with hematuria and new nephrotic range proteinuria. Due to concerns of rejection, he underwent kidney biopsy which revealed non-caseating granulomas withtubulointerstitial inflammation and crescentic changes. GMS stain demonstrated fungal forms consistent with H. capsulatum, effectively establishing the diagnosis of disseminated histoplasmosis. Repeat urine histoplasma antigen >12ng/mL. Blood cultures positive for H.capsulatum days after diagnosis. CNS involvement suspected due to focal lateral ventricle edema on MRI.

Discussion

Evaluation for histoplasma and other endemic fungi should be part of the evaluation for rejection, especially with expanding geographic ranges of endemic fungi. Consider re-testing of antigen before escalating immunosuppressive therapy or pursuing invasive testing. All transplant recipients require therapy for histoplasmosis, duration is determined by disease extent. Our patient received 7 weeks IV lipid amphotericin B with planned12-month course of itraconazole, though may require life-long suppression. This is the first case report of diagnosis of disseminatedhistoplasmosis through kidney biopsy to our knowledge.