Minuto Francesco, Resmini Eugenia, Boschetti Mara, Arvigo Marica, Sormani Maria Pia, Giusti Massimo, Ferone Diego, Barreca Antonina
Department of Endocrinology and Metabolism, University of Genova, Genova, Italy.
Clin Endocrinol (Oxf). 2004 Jul;61(1):138-44. doi: 10.1111/j.1365-2265.2004.02064.x.
It has been suggested that the threshold of 1 micro g/l of GH nadir after glucose load for definition of controlled acromegalic disease proposed in the 2000 consensus statement should be lowered to 0.30. We evaluated these two cut-off values in comparison with IGF-I, ALS and IGFBP-3 in a group of acromegalic patients. With the aim of simplifying the follow-up protocol in these patients we also tested if one single sample taken after glucose load could replace the nadir value.
GH secretion was evaluated by oral glucose tolerance test (OGTT), and by studying spontaneous secretion (GH day curve) with sampling at hourly intervals from 08.00 to 18.00 h; from the day curve, mean (MGHDC) and minimum (TRGH) values were considered. IGF-I, ALS, and IGFBP-3 were measured in the basal state at the first testing. patients Fifty acromegalic patients (26-83 years, 31 females, 19 males) in various phases of disease activity. Forty-two patients had previously undergone pituitary surgery (10 also radiotherapy), 23 were treated with SMS analogues and three with dopamine agonist drugs.
The nadir GH value after glucose load correlated most significantly with the 120th-minute sample (R = 0.95). Comparison of the postglucose 120th minute at the two cut-off values with IGF-I, IGFBP-3 and ALS showed higher concordance of postglucose level at 0.3 with IGF-I, while concordance was similar for the two cut-off values with ALS and IGFBP-3. When the 120th minute postglucose GH value is lower than 1 micro g/l and IGF-I is within 2SD for age nearly all other parameters are normal. IGF-I correlated more with ALS (R = 0.78) than with IGFBP-3 (R = 0.50) and the latter was less concordant with GH secretion parameters than the previous two.
A sample taken at the 120th minute after glucose load, together with IGF-I and/or ALS evaluation can give sufficient information for a routine assessment of disease activity, both in the diagnosis and in the follow-up to treatment. If GH is lower than 1 micro g/l and IGF-I/ALS are normal, then the patient can be classified as 'nonactive' or 'controlled'; a pathological IGF-I and/or ALS value is a sign of disease activity irrespective of the GH values, while normal IGF-I/ALS with an elevated GH requires further assessment.
有人建议，2000年共识声明中提出的用于定义控制良好的肢端肥大症疾病的葡萄糖负荷后生长激素（GH）最低点阈值1μg/L应降至0.30μg/L。我们在一组肢端肥大症患者中评估了这两个临界值，并与胰岛素样生长因子-I（IGF-I）、酸性不稳定亚基（ALS）和胰岛素样生长因子结合蛋白-3（IGFBP-3）进行了比较。为了简化这些患者的随访方案，我们还测试了葡萄糖负荷后采集的单个样本是否可以替代最低点值。
通过口服葡萄糖耐量试验（OGTT）评估GH分泌，并通过从08:00至18:00每小时采样研究自发分泌（GH日曲线）；从日曲线中，考虑平均值（平均GH日曲线，MGHDC）和最小值（谷值GH，TRGH）。在首次检测时测量基础状态下的IGF-I、ALS和IGFBP-3。50例肢端肥大症患者（年龄26 - 83岁，女性31例，男性19例）处于疾病活动的不同阶段。42例患者先前接受过垂体手术（10例还接受了放疗），23例接受生长抑素类似物治疗，3例接受多巴胺激动剂药物治疗。
葡萄糖负荷后GH最低点值与120分钟样本的相关性最为显著（R = 0.95）。将两个临界值下葡萄糖负荷后120分钟时的数值与IGF-I、IGFBP-3和ALS进行比较，结果显示，在0.3μg/L时葡萄糖负荷后水平与IGF-I的一致性更高，而对于ALS和IGFBP-3，两个临界值的一致性相似。当葡萄糖负荷后120分钟时的GH值低于1μg/L且IGF-I在年龄的2个标准差范围内时，几乎所有其他参数均正常。IGF-I与ALS的相关性（R = 0.78）高于与IGFBP-3的相关性（R = 0.50），并且后者与GH分泌参数的一致性低于前两者。
葡萄糖负荷后120分钟采集的样本，连同IGF-I和/或ALS评估，可以为疾病活动的常规评估提供足够信息，无论是在诊断还是治疗随访中。如果GH低于1μg/L且IGF-I/ALS正常，则患者可被分类为“非活动”或“控制良好”；IGF-I和/或ALS值异常是疾病活动的标志，与GH值无关，而IGF-I/ALS正常但GH升高则需要进一步评估。
