Abernethy L J, Davidson D C, Lamont G L, Shepherd R M, Dunne M J
Royal Liverpool Children's NHS Trust Alder Hey.
Arch Dis Child. 1998 Apr;78(4):359-63. doi: 10.1136/adc.78.4.359.
To investigate the use of a calcium infusion test in the diagnosis and localisation of insulin secreting tumours in children.
Three patients with persistent hypoglycaemia of infancy (PHHI).
During planned selective coeliac and mesenteric arteriography, serial samples were taken from a catheter in the right hepatic vein for insulin measurement following the injection of calcium gluconate.
In all three children, selective intra-arterial calcium stimulation produced a significant rise in plasma insulin and was of value in localising the pancreatic abnormality in one child. In vitro studies on islets of Langerhans isolated from this patient following partial pancreatectomy showed unresponsive intracellular calcium signalling of the cells when stimulated with high extracellular concentrations of glucose and potassium or with sulphonylurea drugs (tolbutamide), but normal responsiveness to increasing extracellular calcium concentrations.
The findings suggest a functional abnormality of the calcium channel in PHHI and provide a rationale for the reported efficacy of channel blocking drugs in this condition. The role of selective intra-arterial calcium stimulation in the diagnosis of hyperinsulinaemic hypoglycaemia in childhood warrants further investigation.
探讨钙剂输注试验在儿童胰岛素分泌肿瘤诊断及定位中的应用。
3例婴儿持续性低血糖症（PHHI）患者。
在计划进行的选择性腹腔动脉和肠系膜动脉造影期间，注射葡萄糖酸钙后，从右肝静脉导管中采集系列样本用于胰岛素测定。
在所有3例儿童中，选择性动脉内钙刺激使血浆胰岛素显著升高，并且对1例儿童的胰腺异常定位有价值。对该患者行部分胰腺切除术后分离的胰岛进行的体外研究显示，当用高细胞外浓度的葡萄糖、钾或磺脲类药物（甲苯磺丁脲）刺激时，细胞内钙信号无反应，但对细胞外钙浓度升高反应正常。
这些发现提示PHHI中钙通道存在功能异常，并为报道的通道阻滞剂在这种情况下的疗效提供了理论依据。选择性动脉内钙刺激在儿童高胰岛素血症性低血糖症诊断中的作用值得进一步研究。
