目的 探讨IgA肾病（IgA nephropathy， IgAN）患者淋巴细胞亚群和肾脏临床病理特征及肾脏预后的关系。 方法 回顾性收集和分析2018年1月至2022年1月期间在河北医科大学第四医院肾内科经肾活检确诊的IgAN患者的一般临床资料及病理检查结果。通过相关性检验探讨淋巴细胞亚群与其他重要临床病理参数之间的关系。通过计算约登指数（Youden index）获得CD4⁺ T淋巴细胞的最佳截断值并以此分组。采用Kaplan-Meier生存曲线法及Cox回归法比较IgAN患者CD4⁺ T淋巴细胞与肾功能进展的关系。研究终点事件定义为患者估算肾小球滤过率（eGFR）较基线值下降≥ 30%，和（或）患者进入终末期肾病（end stage renal disease， ESRD）［eGFR < 15 mL/（min·1.73 m²）］或肾脏替代治疗的表现］和（或）全因死亡。 结果 低CD4⁺ T淋巴细胞与IgAN患者的血IgA和肾小球新月体比例呈正相关（P < 0.05）。共53例IgAN患者纳入研究，低CD4⁺ T淋巴细胞组20例，高CD4⁺ T淋巴细胞组33例。低CD4⁺ T淋巴细胞组患者男性较多，新月体比例较低（P < 0.05）。Kaplan-Meier生存曲线分析结果显示，CD4⁺ T淋巴细胞低的患者肾脏累积存活率低（Log-Rank检验χ² = 4.188，P = 0.041）。Cox回归分析结果显示，低CD4⁺ T淋巴细胞是IgAN患者肾功能进展的危险因素（HR = 2.614，95%CI：1.006 ~ 6.788，P = 0.048）。 结论 CD4⁺ T淋巴细胞水平高时，发生肾脏不良预后的风险低。IgAN患者低CD4⁺ T淋巴细胞的肾脏存活率低。

Objective To examine the association between lymphocyte subsets and renal clinicopathological characteristics as well as prognosis in patients with IgA nephropathy （IgAN）. Methods The retrospective analysis included general clinical data and pathological examination results of IgAN patients diagnosed by renal biopsy at the Fourth Hospital of Hebei Medical University from January 2018 to January 2022. Correlation tests were conducted to examine the relationship between lymphocyte subsets and other significant clinicopathological parameters. The optimal cut?off value of CD4⁺ T determined using the Youden index， and patients were grouped accordingly. Kaplan?Meier survival curves and Cox regression analyses were employed to compare the low and high CD4⁺ T lymphocyte groups among IgAN patients， identifying factors influencing renal function progression. The endpoint event was defined as a decrease in estimated glomerular filtration rate （eGFR） of ≥ 30% from baseline， progression to end?stage renal disease （ESRD） ［eGFR < 15 mL/（min·1.73 m²） or initiation of renal replacement therapy］， or all?cause mortality. Results Low CD4⁺ T lymphocytes were significantly positively correlated with blood IgA levels and the proportion of glomerular crescents in IgAN patients （all P < 0.05）. This study included a total of 53 IgAN patients， divided into two groups based on CD4⁺ T lymphocyte counts： 20 patients in the low CD4⁺ T lymphocyte group and 33 patients in the high CD4⁺ T lymphocyte group. In the low CD4⁺ T lymphocyte group， there was a higher proportion of males and a lower proportion of glomerular crescents （P < 0.05）. Kaplan?Meier survival analysis revealed that patients with low CD4⁺ lymphocytes had a significantly lower cumulative renal survival rate （Log?Rank test χ² = 4.188， P = 0.041）. Cox regression analysis indicated that low CD4⁺ lymphocytes were an independent risk factor for the progression of renal function decline in IgAN patients （HR = 2.614， 95% CI： 1.006 ~ 6.788， P = 0.048）. Conclusions Patients with higher levels of CD4⁺ T lymphocytes exhibit a lower risk of adverse renal outcomes. In contrast， patients with IgA nephropathy and low CD4⁺ T lymphocyte counts tend to have poorer renal survival rates.