肾小球血管襻C4d沉积与IgA肾病活动性病变的关系

C4d staining of the glomerular capillary loop: a marker for disease progression of IgA nephropathy

目的探讨IgA肾病肾小球血管襻补体C4d表达的临床病理意义,以期对IgA肾病的预后判断提供帮助。方法对377例IgA肾病行免疫组化C4d染色,观察C4d阳性率及分布形态特点,并与各项病理学形态特点、各临床指标及3年随访结果进行统计学比较。结果 377例IgA肾病中C4d阴性115例,单纯肾小球系膜区沉积113例,系膜区沉积伴肾小球血管襻沉积149例。血管襻C4d表达主要出现在局灶节段硬化和毛细血管内增生处。具有血管襻C4d沉积的IgA肾病在大部分主要病理形态及临床指标均显著差于C4d阴性组和C4d单纯系膜沉积组(P<0.01),3年内肾存活率亦显著低于后两组。结论出现局灶节段血管襻C4d沉积是IgA肾病活动性病变和预后不良的标志物,值得临床诊治过程中给予充分注意。

Purpose To discuss the clinicopathological significance in patients with IgA nephropathy with C4d focal segmental glomer- ular capillary loop deposition, and to demonstrate its importance in the prognosis of IgA nephropathy. Methods CAd immunohisto- chemical staining was performed on biopsy specimens of 377 patients with IgA neophropathy. The clinical and pathological characteris- tics of the patients at the time of renal biopsy and their progression to end-stage renal disease （ESRD） during 3 years of the follow-up was evaluated according to C4d staining. Results Glomerular deposition of CAd was absent in 115 patients, however, 113 patients showed C4d mesangial deposition, and 149 patients showed C4d glomerular mesangial-capillary loop deposition, which primarily depos- ited on endocapillary proliferation and segmental sclerosis of glomerulars. Patients with C4d mesangial-eapillary loop deposition had worse levels in most of the major pathological and clinical indicators than that in the patients without CAd deposition or with C4d me- sangial deposition （P 〈0.01 ）. Moreover, the 3-year renal survival rate in patients with CAd mesangial-capillary loop deposition was lower than that in patients in the other groups. Conclusions In patients with IgA neophropathy, CAd focal segmental staining of the glomerular capillary loop is an indicator of active lesions and poor prognosis, and this finding must be given adequate attention.