原发肾小管性低钾碱中毒的临床特点

Clinical Characteristics of Primary Renal Tubular Hypokalemic Alkalosis

目的探讨原发肾小管性低钾碱中毒的临床特点。方法收集在天津市儿童医院住院治疗的原发肾小管性低钾碱中毒患儿8例,其中Bartter综合征(BS)、Gitelman综合征(GS)各4例。回顾性分析其临床表现、实验室检查、治疗方法及转归情况。结果 4例BS均婴幼儿期起病,临床表现为间断呕吐、腹泻、脱水、生长发育迟缓。4例GS发病年龄为10～15岁,临床表现为肢体无力、四肢麻木及间断手足搐搦。8例患儿血压均正常。实验室检查均表现为低血钾、代谢性碱中毒、尿钾、尿氯排出增加;4例BS患儿血浆肾素、血管紧张素、醛固酮明显升高;4例GS患儿血管紧张素均升高,血浆肾素升高3例、醛固酮明显升高2例;BS患儿尿钙肌酐比>0.2,GS患儿伴低血镁、尿钙肌酐比<0.2。2例BS患儿B超示双肾回声均匀增强,其中1例左肾盂扩张。单纯补钾或联合补镁、吲哚美辛、螺内酯和卡托普利后症状缓解。结论原发肾小管性低钾碱中毒主要表现为低血钾、代谢性碱中毒、血压正常。检查其血镁、尿钾、尿氯、尿钙肌酐比和血浆肾素、血管紧张素、醛固酮水平可帮助诊断。BS和GS的发病机制、临床表现、治疗及预后均有不同。

Objective To explore the clinical characteristics of primary renal tubular hypokalemic alkalosis.Methods Eight patients with primary renal tubular hypokalemic alkalosis were selected in the Children′s Hospital of Tianjin.There were 4 patients with Bartter syndrome（BS） and 4 patients with Gitelman syndrome（GS）.Clinical data,biochemical tests,therapy and outcome were retrospectively analyzed.Results The onset age of BS were at infancy stage.The main symptoms included diarrhea,vomiting,dehydration and growth retardation.And the onset age of GS ranged from 10 to 15 years old with the main symptoms of weakness,paralysis and tetany.They had normal blood pressure.The biochemical tests showed hypokalemic,metabolic alkalosis,increase of urine potassium and urine chlorine in all patients.Four patients with BS had hyperreninemia and hyperaldosteronism.Angiotonin was elevated in all 4 patients with GS,while rennin was elevated in 3 patients of them and aldosterone was obviously elevated in 2 patients.The urine Ca/Cr ratio in BS was elevated（0.2）,while patients with GS had hypomagnesaemia and low level of urine Ca/Cr ratio（0.2）.B-type ultrasonic wave showed that both kidneys′s resonance had even reinforce in 2 patients with BS,and one of them had left pyelectasis.All symptoms resolved after treatment with potassium or combined magnesium supplementation,indomethacin,spironolactone and captopril.Conclusions Primary renal tubular hypokalemic alkalosis is characterized by hypokalemic,metabolic alkalosis,hyperreninemic,hyperaldosteronism and normal blood pressure.Measured level of serum magnesium,urine potassium and chlorine and Ca/Cr ratio,rennin angiotonin and aldosterone can help make diagnosis.There are differences in onset mechanism,clinical manifestation,treatment and prognosis between BS and GS.