Barr D G, Forfar J O
Br Med J. 1969 Feb 22;1(5642):477-80. doi: 10.1136/bmj.1.5642.477.
An oral calcium-loading test suitable for infants is described and the usual response defined. In four acute cases of idiopathic hypercalcaemia a high and sustained rise in serum calcium occurred, suggestive of hyperabsorption and consistent with a vitamin-D-like effect. In four further infants with a milder illness suggestive of hypercalcaemia the fasting calcium levels were not grossly raised, but the test produced an exaggerated hypercalcaemic response. In this type of patient the test is more sensitive in the diagnosis of idiopathic hypercalcaemia than isolated measurements of serum calcium, especially if these are taken in the fasting state. Five patients on treatment and three whose treatment had been discontinued (but who subsequently relapsed or made a poor recovery) showed abnormal loading tests at a time when fasting calcium levels were normal. In two cases full recovery from the disease was associated with reversion of the test to normal. The test can therefore be used to indicate activity of the disease and consequently as a guide to therapy. In two cases a persistently abnormal loading test was associated with a poor long-term prognosis.
本文描述了一种适用于婴儿的口服钙负荷试验，并明确了其通常的反应。在4例特发性高钙血症急性病例中，血清钙出现了高且持续的升高，提示钙吸收过多，与维生素D样效应一致。在另外4例病情较轻、提示有高钙血症的婴儿中，空腹血钙水平没有明显升高，但该试验产生了过度的高钙血症反应。对于这类患者，该试验在诊断特发性高钙血症方面比单独测量血清钙更敏感，尤其是在空腹状态下进行测量时。5例正在接受治疗的患者和3例已停止治疗（但随后复发或恢复不佳）的患者，在空腹血钙水平正常时，负荷试验显示异常。在2例病例中，疾病完全康复与试验恢复正常相关。因此，该试验可用于指示疾病的活动情况，从而作为治疗的指导。在2例病例中，负荷试验持续异常与长期预后不良相关。
