Ventrucci M, Cipolla A, Di Stefano M, Ubalducci G M, Middonno M, Ligabue A, Roda E
Department of Internal Medicine and Gastroenterology, University of Bologna, Italy.
Int J Pancreatol. 1998 Feb;23(1):17-23. doi: 10.1007/BF02787499.
Near infrared reflectance analysis (NIRA) is a useful test for diagnosing fat malabsorption. Three-day stool collection and determination of fecal fat output are recommended. The measurement of fat concentration on spot samples may be of some use only in screening malabsorption of pancreatic origin; moreover, it does not discriminate between steatorrhea resulting from pancreatic insufficiency and that caused by gastrointestinal disorders.
NIRA has been proposed as an accurate method for the determination of fecal fat excretion. The aim of this study was to ascertain whether utilization of this technique to measure fat concentration in spot samples of feces is useful in screening for malabsorption.
Twenty-five patients with chronic pancreatic disease and 95 with other digestive disorders were studied. In all patients, fecal fat assay with NIRA was performed on three different samples from each daily stool collection for 3 d. In 14 patients with pancreatic disease and 21 with gastrointestinal disorders, a colorimetric assay for fecal fat was performed for comparison.
When mean 3-d or daily fat fecal output were considered, a strict linear relationship was found between NIRA and the colorimetric method (r = 0.97 and 0.94, respectively). Using fat concentration, the two tests correlated less well (r= 0.74). Fat concentration was significantly higher in pancreatic than in nonpancreatic steatorrhea, even though values overlapped widely, and thus discrimination was not possible. The diagnostic efficiency of fat concentration for pancreatic and nonpancreatic steatorrhea was 72 and 61%, respectively.
近红外反射率分析（NIRA）是诊断脂肪吸收不良的一项有用检测方法。建议进行为期三天的粪便收集并测定粪便脂肪排出量。仅在筛查胰腺源性吸收不良时，即时样本的脂肪浓度测量可能有一定作用；此外，它无法区分胰腺功能不全导致的脂肪泻和胃肠道疾病引起的脂肪泻。
NIRA已被提议作为测定粪便脂肪排泄的一种准确方法。本研究的目的是确定利用该技术测量粪便即时样本中的脂肪浓度对筛查吸收不良是否有用。
对25例慢性胰腺疾病患者和95例其他消化系统疾病患者进行了研究。对所有患者，连续3天每天收集的粪便中的三个不同样本进行NIRA粪便脂肪检测。对14例胰腺疾病患者和21例胃肠道疾病患者进行了粪便脂肪比色法检测以作比较。
当考虑平均3天或每日粪便脂肪排出量时，发现NIRA与比色法之间存在严格的线性关系（分别为r = 0.97和0.94）。就脂肪浓度而言，两种检测方法的相关性较差（r = 0.74）。胰腺性脂肪泻患者的脂肪浓度显著高于非胰腺性脂肪泻患者，尽管数值有很大重叠，因此无法区分。脂肪浓度对胰腺性和非胰腺性脂肪泻的诊断效率分别为72%和61%。
