Abstract: TH-PO975
IgA Dominant Infection-Related Glomerulonephritis in the Setting of Acute Ehrlichiosis
Session Information
- Glomerular Trainee Case Reports
November 07, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Report
- 1203 Glomerular Diseases: Clinical, Outcomes, and Trials
Authors
- Chowdhury, Zafira, NYU Winthrop Hospital, Mineola, New York, United States
- Borshchenko, Yevgeniy, NYU Winthrop, Mineola, New York, United States
- Stokes, Michael Barry, Columbia University Medical Center, New York, New York, United States
- Khatri, Minesh, NYU Winthrop, Mineola, New York, United States
- Masani, Naveed N., NYU Winthrop, Mineola, New York, United States
Introduction
IgA-Dominant staining on immunofluorescence (IF) with diffuse endocapillary proliferative glomerulonephritis (GN) on light microscopy (LM) has a differential diagnosis that includes primary IgA nephropathy, Henoch-Schönlein purpura (HSP), and IgA-dominant infection related GN. We report a case of acute ehrlichiosis infection with concomitant GN. To date, there have been no reported cases of ehrlichiosis associated GN.
Case Description
A 70-year-old male with a petechial rash, 13 pound weight gain, bilateral lower extremity edema, and serum creatinine 1.6 mg/dl (12 months prior to presentation was 1.0 mg/dl). Urinalysis revealed 3+ protein, 2+ blood; protein:creatinine ratio of 5.3 g/g (urinalysis 12 months previously was negative for blood and protein). Serum albumin was 3.8 g/dL. Glomerular serologies, including complement levels and antineutrophil cytoplasmic antibodies, were either normal or negative. An IgM titer for Ehrlichiosis chaffeensis was strongly positive at 3.7 (normal < 1.0).
Renal biopsy findings revealed diffuse endocapillary proliferation, widespread mesangial and global endocapillary hypercellularity, endothelial swelling, and mild activity. Of note, there was significant intracapillary leukocyte accumulation including neutrophils. There was minimal patchy tubular atrophy and interstitial fibrosis, comprising 10% of the cortex. IF was significant for 2+ IgA and 1+ C3. Electron microscopy revealed electron dense deposits in the mesangium and subendothelial locations, along with 40% foot process effacement. No subepithelial humps were identified.
Given the patient’s clinical timing of acute ehrlichiosis infection and GN, these findings support the diagnosis of an IgA-dominant infection related GN. The presence of neutrophils on LM and 1+ C3 staining on IF, albeit less than the IgA staining of 2+, also support the diagnosis.
Discussion
The LM pattern of proliferative GN with IgA dominance requires clinical correlation. Specific laboratory and biopsy findings including degree of IgA and C3 staining and presence of neutrophils can help distinguish this entity from HSP and IgA nephropathy, as well as timing of renal dysfunction with relationship to onset of infection.