Chen Yu-Ting, Jiang Wen-Ze, Lu Ke-Da
The First Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou 310053, Zhejiang Province, China.
Department of Nephrology, The Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310005, Zhejiang Province, China.
World J Clin Cases. 2023 Sep 6;11(25):5947-5953. doi: 10.12998/wjcc.v11.i25.5947.
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.
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 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.
Our case highlights the significance of performing kidney biopsy and genetic testing in the diagnosis of AS and familial IgA nephropathy.
Alport综合征（AS）是一种由编码IV型胶原α3、α4或α5链的基因突变引起的肾小球基底膜遗传性疾病。其表现为血尿或蛋白尿，常伴有听力障碍和眼部异常。组织病理学上，AS表现为系膜增生，有时伴有免疫球蛋白A（IgA）沉积。血尿或蛋白尿也是IgA肾病患者的常见表现，这使得仅根据这些临床和病理特征难以鉴别诊断AS和IgA肾病。
在此，我们报告一例59岁女性患者，因持续镜下血尿和偶尔蛋白尿入院，症状持续超过2年。该患者有肾病家族史，根据肾活检结果以及使用全外显子测序进行的基因检测，被诊断为常染色体显性AS（ADAS）和IgA肾病，基因检测提示患者携带一种新的杂合变异（c.888G>A:p.Gln296Gln），丰富了ADAS的突变谱。确诊后，先证者接受了血管紧张素受体阻滞剂治疗。治疗一年后，蛋白尿显著减少。每高倍视野镜下红细胞数量降至基线水平的四分之一。随访期间肾功能也保持良好。
我们的病例强调了肾活检和基因检测在AS和家族性IgA肾病诊断中的重要性。
