重症患儿低C肽水平变化及其临床意义

Clinical study of low C-peptide level in critically ill children

目的：分析重症患儿血清C肽下降与病情危重度的关系。方法以2012－11-2013－06入住湖南省儿童医院儿科重症监护室（ PICU）且血清C肽下降的256例重症患儿为研究对象（C肽＜0．78 ng／mL），C肽0．39-0．78 ng／mL为轻度降低组（n＝174），C肽＜0．39 ng／mL为重度降低组（ n＝82）。监测入住PICU 24 h内、3 d、7 d的C肽、胰岛素和血糖，入院时检测电解质、白细胞、降钙素原、乳酸、红细胞压积、心肌酶、淀粉酶、肝肾功能相关指标及胰腺超声等，并记录与病情危重度及预后相关的指标。结果①低C肽患儿入院后C肽水平呈上升趋势，第3天稍高于正常，第7天恢复正常范围；②低C肽患儿入院后第3天胰岛素和血糖均升高并仍稍高于正常，第7天恢复正常范围；③C肽水平与WBC、PCT、乳酸呈负相关，与Ca2＋、氧合指数呈正相关（P＜0．01）；④C肽重度降低组白蛋白水平、小儿危重病例评分（PCIS）评分低于轻度降低组， ALT、AST、LDH和CK－MB水平高于轻度降低组（P＜0．05）；⑤C肽重度降低组PCIS评分低于轻度降低组（P＜0．05）；⑥死亡患儿中7例合并胰腺损伤，其平均C肽水平为（0．34±0．12）ng／mL。结论 C肽降低与炎症反应、缺血、缺氧等因素相关，重症患儿低C肽水平与胰腺损伤、病情严重程度、器官功能障碍和预后有一定关系。

Objective To analyze the variation of serum C -peptide levels in critically ill children and to investigate the underlying mechanism and clinical significance.Methods Two hundred and fifty-six critically ill children admitted in pediatric intensive care unit （ PICU） of Hunan Children＇s Hospital from November 2012 to June 2013 were included.The low C-peptide group （ n=256 ） was defined as insulin levels within 24 h and the patients were divided into two groups according to C -peptide level：mildly declined group （n=174）：0.39-0.78 ng/mL;severe declined group （n=82）：〈0.39 ng/mL.C-peptide, insulin and blood glucose were measured within 24 hours after admission, and on day 3 and day 7.Other results about inflammatory markers, lactate, cardiac enzymes, amylase, pancreatic ultrasound, hepatic and renal function as well as indicators related to severity and prognosis were recorded after admission.Results ①The C -peptide level peak was seen on day 1, then presented a downward trend and closed to the normal level on day 7; ②The blood glucose and insulin level peaks were seen on day 1 then declined, the levels on days 7 were still slightly higher than the normal levels;③The C-peptide level was negatively correlated to WBC, lactic acid and procalcitonin level, and positively correlated Ca2＋, oxidation index （ P 〈0.01）; ④Albumin and PCIS levels in severe declined group were lower than those in mildly declined group, but ALT, AST, LDH and CK-MB levels in severe declined group were higher than those in mildly declined group （P〈0.05）;⑤The incidence of severe sepsis, septic shock and MODS in severe declined group were higher than that imildly declined group （ P 〈0.05）; ⑥Seven cases in death group were complicated with pancreatic damage and the average C-peptide level at admission was （0.34 ±0.12） ng/mL.Conclusion The low C-peptide level is correlated to the degree of inflammatory response, ischemia and hypoxia.The low C-peptide level in critically ill children is relevant to the pancreatic damage, the severity of the disease, organ dysfunction, and evaluation of prognosis.