Keller Jutta, Layer Peter, Brückel Sebastian, Jahr Christine, Rosien Ulrich
From the Department of Internal Medicine, Israelitic Hospital, University of Hamburg, Hamburg, Germany.
Pancreas. 2014 Aug;43(6):842-8. doi: 10.1097/MPA.0000000000000121.
The clinical relevance of pancreatic exocrine insufficiency (PEI) in diabetic patients is unclear mostly because established function tests are invasive and expensive or lack sensitivity and specificity. A modified version of the noninvasive 13C-mixed triglyceride breath test (13C-MTGT) has recently been shown to detect moderate PEI reliably in patients with chronic pancreatitis. Its sensitivity and specificity in other patient groups are unknown. We therefore aimed to clarify the significance of this test for patients with diabetes mellitus (DM).
A secretin cerulein test and a modified 13C-MTGT were performed in 14 patients with DM (10 patients with type 1 DM) and 10 healthy volunteers.
Secretin cerulein test showed significantly lower outputs of amylase, trypsin, and lipase in DM compared with healthy volunteers (P < 0.05). Likewise, 13C-MTGT showed significantly lower maximal and cumulative 13C-exhalation in DM (P < 0.005). Stimulated lipase output correlated with cumulative 13C-exhalation (P < 0.05). However, when compared with normal values, only 2 patients with diabetes had abnormally low lipase output, whereas cumulative 13C-exhalation was pathologically decreased in 8 patients, including those with decreased lipase output.
The noninvasive 13C-MTGT can detect mild to moderate PEI in DM. However, the specificity of the 13C-MTGT is low in these patients probably because nonpancreatic mechanisms contribute to decreased intestinal lipolysis.
糖尿病患者胰腺外分泌功能不全（PEI）的临床相关性尚不清楚，主要是因为现有的功能测试具有侵入性、费用高昂，或者缺乏敏感性和特异性。最近有研究表明，改良版的无创13C混合甘油三酯呼气试验（13C-MTGT）能够可靠地检测出慢性胰腺炎患者的中度PEI。但其在其他患者群体中的敏感性和特异性尚不清楚。因此，我们旨在阐明该测试对糖尿病（DM）患者的意义。
对14例糖尿病患者（10例1型糖尿病患者）和10名健康志愿者进行了促胰液素-胰泌素试验和改良版13C-MTGT。
与健康志愿者相比，糖尿病患者的促胰液素-胰泌素试验显示淀粉酶、胰蛋白酶和脂肪酶的分泌量显著降低（P<0.05）。同样，13C-MTGT显示糖尿病患者的最大和累积13C呼出量显著降低（P<0.005）。刺激后的脂肪酶分泌量与累积13C呼出量相关（P<0.05）。然而，与正常值相比，只有2例糖尿病患者的脂肪酶分泌量异常低，而8例患者的累积13C呼出量呈病理性降低，包括脂肪酶分泌量降低的患者。
无创13C-MTGT能够检测出糖尿病患者的轻度至中度PEI。然而，13C-MTGT在这些患者中的特异性较低，可能是因为非胰腺机制导致肠道脂肪分解减少。
