Abstract: SA-PO236
IgA Nephropathy Associated with Cystic Fibrosis: Role of Recurrent Infections as Etiology
Session Information
- Trainee Case Reports - V
October 27, 2018 | Location: Exhibit Hall, San Diego Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Reports
- 1202 Glomerular Diseases: Immunology and Inflammation
Authors
- Wani, Priyanka, University of California Davis Medical Center, Sacramento, California, United States
- Don, Burl R., University of California Medical Center, Sacramento, California, United States
- Chin, Andrew I., University of California Davis, Sacramento, California, United States
Introduction
Cystic fibrosis (CF), is the most common autosomal recessive condition in the caucasian population, and is due to mutations in cystic fibrosis transmembrane regulator (CFTR) gene that codes for a regulated chloride channel. CF is multisystem disorder primarily affecting the lungs, digestive system, sweat glands and reproductive tract; renal involvement is relatively uncommon in CF despite the high expression of CFTR in the kidney. Reported glomerular diseases associated with CF include AA amyloidosis, membranoproliferative and post-infectious glomerulonephritis. We present a 28 year old Caucasian male with CF who presented with worsening renal function, and nephrotic range proteinuria diagnosed with IgA Nephropathy
Case Description
A 28 year old Caucasian male with CF for over 10 years presented progressive worsening proteinuria from 700 mg/day two years ago to more recently 8 grams/day. His prior renal history included recurrent episodes of respiratory infections and acute kidney injury and the progressive loss of renal function. Evaluation of proteinuria noted negative ANA, ANCA, anti-dsDNA, but a low serum C3. Serum creatinine levels ranged from 2-3 mg/dL. Urine microscopy revealed many dysmorphic RBC’s. A renal biopsy was performed and light microscopy revealed mild to moderate mesangial widening with mesangial hypercellularity but no endocapillary hypercellularity. IF staining was positive for IgA and C3. The tubulointerstitium demonstrated widespread interstitial fibrosis and tubular atrophy. Congo red stain was negative for amyloid. The MEST indices were noted as M1, E0, S0, and T2. The patient was treated conservatively with losartan and without immunosuppression. Renal function remained stable and proteinuria decreased from 8 grams to 5 grams/day over a four month period.
Discussion
Frequent mucosal infections and inflammation, as seen in CF, may be associated with a chronic production of IgA. This patient had an extensive 10 year history of recurrent mucosal infections which were poorly treated. This may have led to aberrant IgA production due to abnormal glycoforms leading to mesangial immune complex deposition and complement activation (low C3) as observed in our case. Therefore recurrent infections associated with CF may have an important role in the pathogenesis of IgA nephropathy.