Suzuki Koichi, Tanaka Hiroshi, Ito Etsuro, Waga Shinobu
Department of Pediatrics, Hirosaki University School of Medicine, 5 Zaifu-cho, Hirosaki 036-8562, Japan.
Pediatr Nephrol. 2004 Feb;19(2):240-3. doi: 10.1007/s00467-003-1362-3. Epub 2003 Dec 11.
Idiopathic (primary) tubulointerstitial nephritis (TIN) of childhood is relatively rare. Four children, two with concomitant uveitis, aged 8-14 years, with idiopathic TIN who underwent repeat renal biopsy were retrospectively evaluated. At presentation, all had a significant elevation of the urinary beta(2)-microglobulin/creatinine ratio (beta2MG ratio), ranging from 10100 to 44550, with increased histological indices of tubulointerstitial scores (TI scores) in excess of 6 points. Three of the children received prednisolone (PSL) therapy following diagnosis, while the remaining child received the therapy 30 months after the first renal biopsy. In the children that received prompt PSL therapy, a rapid decrease in urinary beta2MG ratio was observed and the TI scores obtained at a mean interval of 16 months after the first biopsy decreased to less than 5, while preserving renal function. In the remaining child that received delayed PSL therapy, persistent elevations of urinary beta2MG ratio and TI scores were observed. He subsequently progressed to chronic renal insufficiency. These clinical findings suggest that persistent elevations of urinary beta2MG ratio and TI scores are indicators of progression of renal failure in TIN. For successful treatment, early therapeutic intervention should be deployed in selected patients with severe idiopathic TIN.
儿童特发性（原发性）肾小管间质性肾炎（TIN）相对少见。对4例年龄在8至14岁、患有特发性TIN且接受了重复肾活检的儿童进行回顾性评估，其中2例同时患有葡萄膜炎。初诊时，所有患儿尿β2微球蛋白/肌酐比值（β2MG比值）均显著升高，范围为10100至44550，肾小管间质评分（TI评分）的组织学指标增加超过6分。3例患儿在诊断后接受了泼尼松龙（PSL）治疗，而其余1例患儿在首次肾活检30个月后接受了该治疗。在接受及时PSL治疗的患儿中，观察到尿β2MG比值迅速下降，首次活检后平均间隔16个月时获得的TI评分降至5分以下，同时肾功能得以保留。在接受延迟PSL治疗的其余患儿中，观察到尿β2MG比值和TI评分持续升高。他随后进展为慢性肾功能不全。这些临床发现表明，尿β2MG比值和TI评分持续升高是TIN肾衰竭进展的指标。为了成功治疗，对于选定的重症特发性TIN患者应尽早进行治疗干预。
