Case Report
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Sep 6, 2023; 11(25): 5947-5953
Published online Sep 6, 2023. doi: 10.12998/wjcc.v11.i25.5947
Novel COL4A3 synonymous mutation causes Alport syndrome coexistent with immunoglobulin A nephropathy in a woman: A case report
Yu-Ting Chen, Wen-Ze Jiang, Ke-Da Lu
Yu-Ting Chen, Wen-Ze Jiang, The First Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou 310053, Zhejiang Province, China
Ke-Da Lu, Department of Nephrology, The Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310005, Zhejiang Province, China
Author contributions: Chen YT contributed to manuscript writing and editing, and data collection; Jiang WZ contributed to data analysis; Lu KD contributed to conceptualization and supervision; all authors have read and approve the final manuscript.
Supported by The Major Project of Zhejiang Administration of Traditional Chinese Medicine, No. 2020ZZ008.
Informed consent statement: Informed written consent was obtained from the patient for publication of this report and any accompanying images.
Conflict-of-interest statement: The authors declare that they have no conflict of interest to disclose.
CARE Checklist (2016) statement: The authors have read the CARE Checklist (2016), and the manuscript was prepared and revised according to the CARE Checklist (2016).
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Ke-Da Lu, MD, Doctor, Professor, Department of Nephrology, The Third Affiliated Hospital of Zhejiang Chinese Medical University, No. 219 Moganshan Road, Xihu District, Hangzhou 310005, Zhejiang Province, China. lukedaq@126.com
Received: June 6, 2023
Peer-review started: June 6, 2023
First decision: July 17, 2023
Revised: July 31, 2023
Accepted: August 8, 2023
Article in press: August 8, 2023
Published online: September 6, 2023
Abstract
BACKGROUND

Alport syndrome (AS) is an inherited disease of the glomerular basement membrane caused by mutations in genes encoding α3, α4, or α5 chains of type IV collagen. It manifests with hematuria or proteinuria, which is often accompanied by hearing impairments and ocular abnormalities. Histopathologically, AS shows mesangial proliferation and sometimes incidental immunoglobulin A (IgA) deposition. Hematuria or proteinuria is also a common presentation in patients with IgA nephropathy that makes it difficult to differentially diagnose AS and IgA nephropathy solely based on these clinical and pathological features.

CASE SUMMARY

Herein, we present the case of a 59-year-old female patient who was admitted to our hospital with persistent microscopic hematuria and occasional proteinuria that had lasted for > 2 years. This patient had a familial history of renal disease and was diagnosed with autosomal dominant AS (ADAS) and IgA nephropathy based on the findings of renal biopsy as well as genetic testing performed using whole-exome sequencing, which suggested that the patient carried a novel heterozygous variation (c.888G>A:p.Gln296Gln) in the COL4A3 gene that enriches the mutation spectrum of ADAS. The proband received an angiotensin receptor blocker therapy after a definitive diagnosis was established. After one year of therapy, a significant reduction in proteinuria was observed. The number of microscopic red blood cells per high-power field decreased to one-quarter of the baseline levels. Renal function also maintained well during the follow-up.

CONCLUSION

Our case highlights the significance of performing kidney biopsy and genetic testing in the diagnosis of AS and familial IgA nephropathy.

Keywords: Alport syndrome, Immunoglobulin A nephropathy, COL4A3 gene, Whole-exome sequencing, Renal biopsy, Case report

Core Tip: It is challenging to distinguish between Alport syndrome (AS) and immunoglobulin A (IgA) nephropathy solely based on clinical and pathological findings. This report highlights the diagnostic value of whole-exome sequencing in the precise diagnosis of AS and emphasizes the significance of renal biopsy and genetic detection in the early diagnosis of AS and familial IgA nephropathy.