Abstract：
OBJECTIVE: Alport syndrome (AS) is the most common genetic glomerular disease caused by mutations that affect type IV collagen. However, the clinical characteristics and significance of AS with kidney cysts are not well defined. This study investigated the prevalence and clinical significance of cystic kidney phenotype in AS.
METHODS: Retrospective cohort study.
METHODS: One hundred-eight patients with AS and a comparison cohort of 79 patients with IgA nephropathy (IgAN). Clinical, genetic, and imaging data were collected from medical records.
METHODS: Cystic kidney phenotype evaluated by ultrasonography and defined as the presence of≥3 cysts in each kidney; demographic characteristics and estimated glomerular filtration rate (eGFR) at disease onset.
RESULTS: Cystic kidney phenotype in the AS and IgAN cohorts; time to chronic kidney disease (CKD) stage 3b and longitudinal changes in eGFR in the AS cohort.
METHODS: Logistic regression analysis to test independent strengths of associations of clinical/demographic features with the binary outcome of cystic phenotype. Survival analysis for the outcome of reaching CKD stage 3b and linear mixed models for changes in eGFR over time in the AS cohort.
RESULTS: We studied 108 patients with AS; 76 (70%) had a genetic diagnosis. Autosomal dominant AS was prevalent, accounting for 68% of patients with a genetic diagnosis. Cystic kidney phenotype was observed in 38% of patients with AS and was associated with normal-sized kidneys in all but 3 patients, who showed increased total kidney volume, mimicking autosomal dominant polycystic kidney disease. The prevalence of cystic kidney phenotype was significantly higher in patients with AS when compared with the group of patients with IgAN (42% vs 19%; P=0.002). Patients with the cystic kidney phenotype were older and had more marked reduction in eGFR than patients without cystic changes. Among patients with AS, the cystic phenotype was associated with older age and a faster decline eGFR.
CONCLUSIONS: Retrospective, single-center study.
CONCLUSIONS: Cystic kidney phenotype is a common finding in AS. The cystic kidney phenotype is a common finding in AS, suggesting a possible role in cystogenesis for the genetic variants that cause this disease.
UNASSIGNED: Hematuria is the classic renal presentation of Alport syndrome (AS), a hereditary glomerulopathy caused by pathogenic variants of the COL4A3-5 genes. An atypical kidney cystic phenotype has been rarely reported in individuals with these variants. To determine the prevalence of kidney cysts, we performed abdominal ultrasonography in a large group of patients with AS and a comparison group of patients with another glomerular kidney disease, IgA nephropathy (IgAN). Multiple kidney cysts, usually with normal kidney volume, were found in 38% of patients with AS. A few patients\' kidney volumes were large enough to mimic a different hereditary cystic kidney disease, autosomal dominant polycystic kidney disease. The overall prevalence of kidney cysts in AS was more than double that observed in the well-matched comparison group with IgAN. These findings emphasize the high prevalence of cystic kidney phenotype in AS, suggesting a likely association between the genetic variants that cause this disease and the development of kidney cysts.
METHODS: Retrospective cohort study.
METHODS: One hundred-eight patients with AS and a comparison cohort of 79 patients with IgA nephropathy (IgAN). Clinical, genetic, and imaging data were collected from medical records.
METHODS: Cystic kidney phenotype evaluated by ultrasonography and defined as the presence of≥3 cysts in each kidney; demographic characteristics and estimated glomerular filtration rate (eGFR) at disease onset.
RESULTS: Cystic kidney phenotype in the AS and IgAN cohorts; time to chronic kidney disease (CKD) stage 3b and longitudinal changes in eGFR in the AS cohort.
METHODS: Logistic regression analysis to test independent strengths of associations of clinical/demographic features with the binary outcome of cystic phenotype. Survival analysis for the outcome of reaching CKD stage 3b and linear mixed models for changes in eGFR over time in the AS cohort.
RESULTS: We studied 108 patients with AS; 76 (70%) had a genetic diagnosis. Autosomal dominant AS was prevalent, accounting for 68% of patients with a genetic diagnosis. Cystic kidney phenotype was observed in 38% of patients with AS and was associated with normal-sized kidneys in all but 3 patients, who showed increased total kidney volume, mimicking autosomal dominant polycystic kidney disease. The prevalence of cystic kidney phenotype was significantly higher in patients with AS when compared with the group of patients with IgAN (42% vs 19%; P=0.002). Patients with the cystic kidney phenotype were older and had more marked reduction in eGFR than patients without cystic changes. Among patients with AS, the cystic phenotype was associated with older age and a faster decline eGFR.
CONCLUSIONS: Retrospective, single-center study.
CONCLUSIONS: Cystic kidney phenotype is a common finding in AS. The cystic kidney phenotype is a common finding in AS, suggesting a possible role in cystogenesis for the genetic variants that cause this disease.
UNASSIGNED: Hematuria is the classic renal presentation of Alport syndrome (AS), a hereditary glomerulopathy caused by pathogenic variants of the COL4A3-5 genes. An atypical kidney cystic phenotype has been rarely reported in individuals with these variants. To determine the prevalence of kidney cysts, we performed abdominal ultrasonography in a large group of patients with AS and a comparison group of patients with another glomerular kidney disease, IgA nephropathy (IgAN). Multiple kidney cysts, usually with normal kidney volume, were found in 38% of patients with AS. A few patients\' kidney volumes were large enough to mimic a different hereditary cystic kidney disease, autosomal dominant polycystic kidney disease. The overall prevalence of kidney cysts in AS was more than double that observed in the well-matched comparison group with IgAN. These findings emphasize the high prevalence of cystic kidney phenotype in AS, suggesting a likely association between the genetic variants that cause this disease and the development of kidney cysts.
摘要：
目的：Alport综合征（AS）是由影响IV型胶原的突变引起的最常见的遗传性肾小球疾病。然而,AS合并肾囊肿的临床特征和意义尚不明确。本研究调查了囊性肾表型在AS中的患病率和临床意义。
方法：回顾性队列研究。
方法：&参与者：118例AS患者和79例IgA肾病（IgAN）患者的比较队列。临床,遗传,和影像学数据是从医疗记录中收集的。
方法：通过超声检查评估囊性肾表型，并定义为每个肾脏存在≥3个囊肿。发病时的人口统计学特征和eGFR。
结果：AS和IgAN队列中的囊性肾表型。AS队列中CKD阶段3b的时间和eGFR的纵向变化。
方法：Logistic回归分析，以检验临床/人口统计学特征与囊性表型的二元结局之间的独立强度。在AS队列中达到CKD阶段3b的结果的生存分析和eGFR随时间变化的线性混合模型。
结果：我们研究了108例AS患者；76例（70%）有基因诊断。常染色体显性遗传AS很普遍，占遗传诊断患者的68%。在38％的AS患者中观察到囊性肾脏表型，除3例患者外，所有患者均与正常大小的肾脏相关。显示总肾脏体积增加，模仿常染色体显性多囊肾病（ADPKD）。与对照组的IgAN患者相比，AS患者的囊性肾表型患病率明显更高（42％vs19％；p=0.002）。与没有囊性改变的患者相比，具有囊性肾表型的患者年龄更大，并且eGFR明显降低。在AS患者中，囊性表型与年龄较大和eGFR下降较快有关.
结论：回顾性，单中心研究。
结论：囊性肾表型是AS的常见发现。囊性肾表型是AS中的常见发现，表明引起这种疾病的遗传变异在膀胱形成中可能发挥作用。
方法：回顾性队列研究。
方法：&参与者：118例AS患者和79例IgA肾病（IgAN）患者的比较队列。临床,遗传,和影像学数据是从医疗记录中收集的。
方法：通过超声检查评估囊性肾表型，并定义为每个肾脏存在≥3个囊肿。发病时的人口统计学特征和eGFR。
结果：AS和IgAN队列中的囊性肾表型。AS队列中CKD阶段3b的时间和eGFR的纵向变化。
方法：Logistic回归分析，以检验临床/人口统计学特征与囊性表型的二元结局之间的独立强度。在AS队列中达到CKD阶段3b的结果的生存分析和eGFR随时间变化的线性混合模型。
结果：我们研究了108例AS患者；76例（70%）有基因诊断。常染色体显性遗传AS很普遍，占遗传诊断患者的68%。在38％的AS患者中观察到囊性肾脏表型，除3例患者外，所有患者均与正常大小的肾脏相关。显示总肾脏体积增加，模仿常染色体显性多囊肾病（ADPKD）。与对照组的IgAN患者相比，AS患者的囊性肾表型患病率明显更高（42％vs19％；p=0.002）。与没有囊性改变的患者相比，具有囊性肾表型的患者年龄更大，并且eGFR明显降低。在AS患者中，囊性表型与年龄较大和eGFR下降较快有关.
结论：回顾性，单中心研究。
结论：囊性肾表型是AS的常见发现。囊性肾表型是AS中的常见发现，表明引起这种疾病的遗传变异在膀胱形成中可能发挥作用。
