Zhou Jian-hua, Huang Ai-xia, Liu Tong-lin, Kuang Yu-jiu
Department of Pediatrics, Tongji Hospital, Tongji Medical College of Huazhong University of Science and Technology, Wuhan 430030, China.
Zhonghua Er Ke Za Zhi. 2003 Nov;41(11):808-12.
Henoch-Schonlein purpura nephritis (HSPN) and IgA nephropathy are very similar in immunopathological changes, and therefore some nephrologists considered that they are substantially one disease entity caused by IgA immune abnormalities, and IgA nephropathy is, in fact, a kind of HSPN without rashes. The present study aimed to characterize their relationship through clinico-pathological comparison between IgA nephropathy and HSPN.
Thirty-one children with IgA nephropathy aged from 3 to 15 years and 120 children with HSPN aged between 4 to 15 years were enrolled in this study. Their clinical manifestations, blood biochemical test, serum immunology and follow-up data were collected and analyzed. Renal pathological findings in light microscopy, immunofluorescence and electron microscopy were analyzed and also compared between 31 children with IgA nephropathy and 32 children with HSPN.
The age of onset was over 12 years in 25.8% children with IgA nephropathy, but only in 10% with HSPN, and the difference was significant (P < 0.05). The clinical patterns of IgA nephropathy and HSPN were similar, but extra-renal manifestations were seen more often in HSPN, all of them had skin purpura, 59% had gastrointestinal symptoms and 47% suffered from arthralgia. While the abdominal pain occurred only in 3.2% children with IgA nephropathy. The renal pathological investigation showed global sclerosis in 35.5% of IgA nephropathy and 3.1% of HSPN, mesangial sclerosis in 41.9% of IgA nephropathy and 6.3% of HSPN, but endothelial proliferation in 65.6% of HSPN and 29% of IgA nephropathy. The differences were extremely significant (P < 0.01). Thin basement membrane nephropathy were only found in 6.5% children with IgA nephropathy, but in none with HSPN. The electronic dense deposits in HSPN were sparse, loose and widely spread in glomerular mesangium, subendothelial area and even intra basement membrane. While the deposits were dense, lumpy and mostly limited in mesangium and paramesangium in IgA nephropathy. IgG was found in glomerular immune deposits in 71.9% of HSPN, but only 19.4% of IgA nephropathy. No IgG deposit was observed in 81.6% of IgA nephropathy, among them most showed IgA and IgM and/or C(3) deposit. Predominant IgG deposits were found in 12.5% of HSPN with relatively weak IgA deposit, moreover 6.3% of HSPN showed linear IgG deposits in glomerular capillary wall, which couldn't be found in IgA nephropathy. The follow-up data of average 20 months showed complete remission in 72.5% of HSPN and 19.4% in IgA nephropathy after 34 months follow-up. Moreover, 64.5% of IgA nephropathy had consistent hematuria and proteinuria, 16.1% had active nephritides, the difference was significant (P < 0.05).
Significant clinico-pathological differences were found between HSPN and IgA nephropathy, which does not support the one disease entity hypothesis. HSPN and IgA nephropathy are probably two diseases with similar immune abnormalities.
过敏性紫癜性肾炎（HSPN）与IgA肾病在免疫病理改变上非常相似，因此一些肾脏病学家认为它们实际上是由IgA免疫异常引起的同一疾病实体，IgA肾病实际上是一种无皮疹的HSPN。本研究旨在通过IgA肾病与HSPN的临床病理比较来明确它们之间的关系。
本研究纳入了31例年龄在3至15岁的IgA肾病患儿和120例年龄在4至15岁的HSPN患儿。收集并分析他们的临床表现、血液生化检查、血清免疫学及随访数据。对31例IgA肾病患儿和32例HSPN患儿的肾脏病理检查结果进行了光镜、免疫荧光和电镜分析及比较。
IgA肾病患儿中25.8%起病年龄超过12岁，而HSPN患儿中仅10%，差异有统计学意义（P<0.05）。IgA肾病和HSPN的临床类型相似，但HSPN的肾外表现更常见，所有患儿均有皮肤紫癜，59%有胃肠道症状，47%有关节痛。而腹痛仅在3.2%的IgA肾病患儿中出现。肾脏病理检查显示，IgA肾病35.5%有全球硬化，HSPN为3.1%；IgA肾病41.9%有系膜硬化，HSPN为6.3%；但HSPN内皮细胞增生占65.6%，IgA肾病为29%。差异极为显著（P<0.01）。薄基底膜肾病仅在6.5%的IgA肾病患儿中发现，HSPN患儿中未发现。HSPN的电子致密沉积物稀疏、松散，广泛分布于肾小球系膜、内皮下区域甚至基底膜内。而IgA肾病的沉积物致密、块状，大多局限于系膜和副系膜区。71.9%的HSPN肾小球免疫沉积物中发现IgG，而IgA肾病中仅19.4%。81.6%的IgA肾病未观察到IgG沉积，其中大多数表现为IgA和IgM及/或C3沉积。12.5%的HSPN以IgG沉积为主，IgA沉积相对较弱，此外6.3%的HSPN在肾小球毛细血管壁显示线性IgG沉积，IgA肾病中未发现。平均20个月的随访数据显示，随访34个月后，72.5%的HSPN完全缓解，IgA肾病为19.4%。此外，64.5%的IgA肾病有持续性血尿和蛋白尿，16.1%有活动性肾炎，差异有统计学意义（P<0.05）。
HSPN与IgA肾病之间存在显著的临床病理差异，不支持同一疾病实体假说。HSPN和IgA肾病可能是两种具有相似免疫异常的疾病。
