Abstract: TH-PO719
Diagnosis of Alport Syndrome Requires One More Step after Kidney Biopsy
Session Information
- Glomerular Diseases: Case Reports - 1
October 24, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Salvi, Dhairya, Ascension Providence Rochester Hospital, Rochester, Michigan, United States
- Pineiro De Jesus, Pedro Alberto, Ascension Providence Rochester Hospital, Rochester, Michigan, United States
Introduction
Alport syndrome is an inherited disorder heterogeneously affecting the basement membrane of the kidney, eyes, and inner ear. It is a diagnostic challenge as symptoms are non-specific, with hematuria being the only evident sign in many cases. The age at presentation and genetic modes of transmission also show significant variation. A kidney biopsy may show non-specific findings making further diagnostic tests necessary.
Case Description
We present a case of a 66-year-old female with a history of long-standing hypertension and WHO class II obesity who was referred to our clinic for CKD stage G2A3 with a baseline creatinine of 0.9 mg/dL. She had microscopic hematuria with 5-9 RBCs on urinalysis and subnephrotic proteinuria with urine protein creatinine ratio of 1.8 g/g. Serological workup for glomerulonephritis was negative. Decision was taken to investigate further with a kidney biopsy which showed epithelial foot process effacement, moderate arteriosclerosis, and glomerulomegaly. thin glomerular basement membrane without any lamellation; Immunofluorescence was negative for antibody or complement deposition. An Alport immunofluorescence showed a normal uninterrupted staining for alpha 5 chain of collagen type IV. Given a family history of CKD, there was still some suspicion of a hereditary disorder. Genetic testing revealed COL4A4 variant suggestive of autosomal dominant Alport syndrome.
Discussion
This patient had hematuria, subnephrotic proteinuria, and CKD which can be attributed to a combination of thin basement membrane nephropathy and hypertensive arteriosclerosis, which was evident on kidney biopsy. The patient did not have eye or ear involvement seen in Alport syndrome. Furthermore, the kidney biopsy did not show any lamellation or splitting of glomerular basement membrane. Despite this, the patient was found to have Alport syndrome based on genetic analysis. This case demonstrates the importance of genetic testing for Alport syndrome despite non-specific findings on kidney biopsy in case of hematuria, progressive kidney disease, and a positive family history.