免疫法和化学法粪便隐血试验在上消化道出血性疾病中阳性率的比较

目的:比较免疫法粪便隐血试验(immune fecal occult blood test,IFOBT)和化学法粪便隐血试验(chemical fecal occult blood test.CFOBT)在上消化道出血性疾病中的阳性率,以验证IFOBT筛查上消化道出血不具特异性.方法:2006-07/2007-03间连续选择我院内镜中心进行胃镜检查的上消化道出血性疾病患者206例,利用邻甲苯胺CFOBT和IFOBT同时比较两种粪便隐血试验的阳性率,并结合临床资料分析其相应结果.结果:IFOBT和CFOBT结果均与食管癌、胃癌的解剖部位及食管癌浸润深度无关,两者均与胃癌浸润深度有关,与胃癌的最大长径呈正相关(IFOBT:r=0.30,P=0.02;CFOBT:r=0.20,P=0.04);IFOBT与食管癌的最大长径呈正相关(r=0.38,P=0.01);CFOBT在食管癌患者中的阳性率高于食管磷状细胞癌抗原(SCC)的阳性率(47.43% vs 20.45%,P＜0.05);两者在胃癌患者中的阳性率均高于CA125,CEA和CA199的阳性率.CFOBT检测胃癌、食管癌、返流性食管炎和消化性溃疡的阳性率均高于IFOBT(50.88% vs 35.09%,47.73% vs 29.55%,18.00% vs 6.00%,60.00% vs 41.82%,均P＜0.05).IFOBT在上消化道出血性疾病中的总阳性率低于CFOBT.结论:IFOBT粪便隐血试验不适合上消化道出血性疾病的筛查,可能对下消化道出血性疾病的筛查具有相对特异性.     

大便隐血试验免疫法与化学法检测和比较

目的探讨大便隐血试验化学试剂带法与免疫金标法的灵敏度和特异性。方法化学试剂带半定量法，免疫胶体金法。结果免疫法敏感度高，专一性强，但当被测抗原量多于抗体时，易产生后带现象，而影响结果。结论当被测抗原含量〉抗体时，要用化学试剂带法确诊。     

粪便转铁蛋白试验在提高消化道出血检出率中的作用

目的研究粪便转铁蛋白试验（TFPT）与免疫粪隐血试验（IFOBT）互补的可行性,以提高消化道出血的检出率。方法连续性收集接受胃镜或结肠镜检查患者的粪便,其中上消化道出血性疾病27例,上消化道非出血性疾病31例;下消化道出血性疾病30例,下消化道非出血性疾病16例。分别计算IFOBT和TFPT的敏感性、特异性、阳性预示值、阴性预示值,再计算转铁蛋白试验与粪隐血试验的互补率。结果在上消化道出血性疾病中,TFPT的敏感性（8/27）显著高于IFOBT（2/27）（P〈0.05）。在下消化道出血性疾病中,TFPT的敏感性（25/30）也显著高于IFOBT（16/30）（P〈0.05）。两个试验结合互补后,将上、下消化道出血检出率分别提高到29.6%和83.3%。结论无论是上消化道出血还是下消化道出血,转铁蛋白试验的敏感性均高于免疫粪隐血试验。两个试验结合互补可明显提高消化道出血的检出效率。     

免疫法便隐血试验对大肠良恶性疾病的诊断价值研究

目的探讨免疫法便隐血试验(IFOBT)在诊断大肠良恶性疾病中的诊断价值,提高大肠癌癌前疾病的早期筛查水平。方法对332例行结肠镜检查者进行免疫法便隐血试验,应用OC-MICRO全自动便隐血分析仪对便隐血结果进行分析,分别计算不同阳性阈值下的敏感性、特异性、阳性预测值(PPV)、阴性预测值(NPV)。应用ELISA法检测外周血CEA、CA19-9水平及其敏感性、特异性、PPV、NPV。结果共纳入研究332例,其中男176例(53.0%),女156例(47.0%),分为结肠镜正常组183例,炎症性肠病(IBD)组34例,大肠息肉组79例(其中腺瘤型息肉25例,高危腺瘤12例)和大肠癌组36例。当便隐血试验阳性阈值为200ng/mL时,各组特异度为94.5%,各组敏感度分别为88.2%(IBD组)、86.1%(大肠癌组)、52.0%(腺瘤型息肉组)、50.0%(高危腺瘤组)和34.2%(大肠息肉组),与阳性阈值为100 ng/mL和150 ng/mL时相比较均无显著差异(P0.05)。外周血CEA在正常组、IBD组和大肠息肉组之间无显著差异(P0.05),大肠癌组和正常组之间有显著差异(P=0.006)。外周血CA19-9在正常组、IBD组和大肠癌组之间无显著差异(P0.05)。CEA、CA19-9及二者联合检测其特异度均为100%,与免疫法便隐血无显著差异(P=1.000),其敏感度在IBD组、大肠息肉组、腺瘤型息肉组、高危腺瘤组和大肠癌组分别为:CEA(0、6.7%、0、8.3%、36.7%)、CA19-9(0、0、0、0、16.7%)、二者联合(0、3.3%、0、8.3%、40.0%)。CEA、CA19-9在诊断大肠癌时敏感度均低于免疫法便隐血(P=0.000),其PPV与免疫法便隐血无显著差异(P0.05),NPV明显低于免疫法便隐血(P=0.000)。在诊断高危腺瘤时,免疫法便隐血NPV明显高于肿瘤标志物(P=0.000),敏感度、特异度和PPV均与肿瘤标志物无显著差异(P均0.05)。结论免疫法便隐血在IBD、大肠腺瘤型息肉和大肠癌的诊断方面具有较高的敏感性和特异性,在大肠癌的诊断中比CEA、CA19-9具有更高的敏感度,该方法是较好的大肠良恶性疾病筛查和诊断的指标。     

粪便DNA与粪隐血试验机会性筛查大肠肿瘤的比较研究

[目的]探讨粪便DNA检测在大肠肿瘤机会性筛查中的价值。[方法]进入筛查的人群中连续收集46例大肠癌(CRC)、60例大肠腺瘤(CRA)及30例正常粪便标本,采用PCR-SSCP银染法检测粪便DNA突变情况,并与免疫法粪便隐血试验(IFOBT)比较。[结果]CRC组、CRA组和正常组IFOBT的阳性率分别为45.7%(21/46)、18.3%(11/60)和13.33%(4/30);CRC组、CRA组和正常组APC的突变率分别为58.7%(27/46)、20.0%(12/60)和3.33%(1/30),p53的突变率分别为65.2%(30/46)、25.0%(15/60)和0%(0/30),K-ras的突变率分别为60.9%(28/46)、23.3%(14/60)和0%(0/30),粪便DNA 3个基因联合检测的突变率分别为76.1%(35/46)、35.0%(21/60)和3.33%(1/30)。CRC组、CRA组中APC、p53、K-ras基因单独检测的敏感性与IFOBT比较,差异均无统计学意义(P0.05);CRC组、CRA组粪便DNA 3个基因联合检测的敏感性均高于IFOBT,差异有统计学意义(P0.05);CRC组、CRA组粪便DNA 3个基因单独和联合检测大肠肿瘤的特异性均高于IFOBT,但均差异无统计学意义(P0.05)。[结论]粪便DNA联合检测大肠肿瘤的敏感性高于IFOBT,提示粪便DNA检测可能是更适于机会性筛查大肠肿瘤的无创性筛查方法。     

免疫法与化学法粪便潜血试验在结肠癌筛查中价值的荟萃分析

目的系统性评价免疫法粪便潜血试验(immunochemical fecal occult blood tests,iFOBT)与愈创木脂化学法粪便潜血试验(guaiac-based fecal occult blood tests,gFOBT)相比,是否能获得更高的筛检进展期结直肠肿瘤的临床应用价值。方法利用中英文检索词检索相关电子数据库,纳入直接比较iFOBT与gFOBT筛查结直肠肿瘤的随机临床试验,并提取其特征信息。根据QUADAS质量评价标准评价纳入文献的质量,荟萃分析各项研究中不同潜血试验方法对结直肠肿瘤的检出率和患者的依从性,计算相应的OR值和95%可信区间。通过漏斗图肉眼观察是否存在发表偏倚,并做Egger检验进一步验证。结果共5项随机临床试验(共22 709例)符合纳入标准。iFOBT与gFOBT对于结直肠癌及进展期腺瘤的检出率分别为2.23%和1.24%,合并OR值为1.50(95%CI:0.94~2.39)。而这种优越性主要体现在iFOBT与传统的化学法HemoccultⅡ相比时(OR=2.12,95%CI:1.66~2.71)。患者对于iFOBT和gFOBT的依从性分别为52.66%和43.93%,合并OR值为1.40(95%CI:1.16~1.68)。结论与传统gFOBT相比,iFOBT能够提高结直肠肿瘤筛检的准确性及患者的依从性。     

粪便转铁蛋白和免疫粪隐血试验在结直肠癌筛查中效能的比较

目的评估粪便转铁蛋白(TF)和免疫粪隐血试验(IFOBT)在筛查结直肠癌中的效能。方法筛查对象为1 943例无症状受试者。收集1次粪便标本,同时用于TF和IFOBT检测。两者任一结果为阳性,即通知受试者行结肠镜检查。分别计算TF、IF-OBT和两者联合检测的性能指标。结果共有1 737例受试者接受TF和IFOBT检查,其中251例(14.5%)至少1项结果为阳性。共有193例接受结肠镜检查,共发现3例结直肠癌和43例进展期腺瘤。与单独使用IFOBT相比,TF和IFOBT联合检测(并联)明显提高了结直肠癌和进展期腺瘤的检出率(2.6%vs 1.6%,P=0.034)。结论 TF和IFOBT联合检测能提高筛查时结直肠癌和进展期腺瘤的检出率。     

粪便隐血试验在结直肠癌早期筛查中的研究现状

在全球范围内结直肠癌是位居发病率第四、死因第二位的恶性肿瘤。在西方国家人群中，结直肠癌在人一生中的发病率约为6％，死亡率高达60％。我国目前结直肠癌发病率亦呈递增趋势，并成为中国癌症死亡的最常见病因。目前粪便隐血试验（FOBT）仍是应用于大系列人群筛查结直肠癌唯一简单可行的方法。本文简要阐述近年来FOBT在大系列人群中筛查早期结直肠癌的临床研究进展，并对愈创木脂法和免疫化学法作一简要介绍和比较。     

免疫法粪便潜血试验在结直肠癌筛查中的价值

目的 探讨免疫法粪便潜血试验(IFOBT)在大系列健康体检人群中筛查结直肠癌及其癌前病变的临床价值.方法 对2006年7月至2007年6月间在上海交通大学医学院附属仁济医院行健康体检的5919例采用IFOBT筛查结直肠癌及其癌前病变,对阳性病例进行结直肠镜检查或x线钡剂灌肠检查,结合临床及病理资料进行分析.结果 5919例体检人群中IFOBT阳性者314例,阳性率为5.30%,其中241例(76.75%)接受了结直肠镜检查,23例(7.32%)接受了X线钡剂灌肠检查,总随访率达84.08%,失访50例.剔除失访病例后,共发现结直肠癌16例,检出率为2.73‰(16/5869),其中Dukes A期8例(50.00%),Dukes B期7例(43.75%),Dukes C期1例(6.25%),IFOBT阳性者中的结直肠癌检出率为6.06%(16/264).共发现结直肠腺瘤样息肉94例,检出率为16.01‰(94/5869),包括管状腺瘤55例(58.51%),绒毛状-管状腺瘤23例(24.47%),绒毛状腺瘤16例(17.02%),其中单发者55例(58.51%),多发者39例(41.49%);另见活动期溃疡性结肠炎6例.IFOBT阳性者中共检出116例结直肠癌或癌前病变,检出率为43.94%(116/264).结论 IFOBT适合于大系列人群结直肠癌及其癌前病变的筛查,能发现较早期结直肠癌和癌前病变,使疾病在可治愈阶段得到根治,从而有望减少结直肠癌的发病率和死亡率.     

凝血酶灌肠法在急性下消化道出血中的应用价值

下消化道出血临床常见,病因繁多.急性大量出血常常会危及生命,尤其对老年病人伴有心脑血管疾病者,其诊断、治疗在临床上均有一定困难.我院采用凝血酶灌肠法在处理急性下消化道大出血中取得良好效果,一方面起止血治疗作用,同时为结肠镜检查做好肠道清洁准备.本文总结了我院1997～2002年收治的急性下消化道出血30例的诊治经验,探讨如何进一步提高诊治水平.     

Relationship between the fecal occult blood test and benign anal disorders

BACKGROUND/AIMS: The fecal occult blood test is a very useful method for mass screening for colorectal cancer. The possibility of the fecal occult blood test being positive is high even in benign anal disorders, but the relationship between anal disorders and the fecal occult blood test has not been fully studied. METHODOLOGY: During the period from November 1995 to April 1996, we performed both fecal occult blood test and sigmoid colonofiberscopy for 440 patients with anal disorders who visited our hospital for the first time. RESULTS: The positive fecal occult blood test rate was 18.8% (77/409) for those who had only anal disorders and no findings in the colon and rectum. The positive fecal occult blood test rate was significantly high in the cases with polyps (42.3%) and in those with colorectal cancer (60%). CONCLUSIONS: These findings suggested the need to analyze fecal occult blood test, keeping in mind that fecal occult blood test might be positive even without any malignant findings in the large intestine in about 20% of cases of patients have anal disorders when fecal occult blood test is performed.     

Reliability of chemical tests for fecal occult blood in hospitalized patients

In 39 hospitalized patients with suspected gastrointestinal bleeding and given intravenous⁵¹Cr-labeled red cells, reactions of three chemical spot tests for fecal occult blood were compared with the true blood loss as determined by stool radioassay. Guaiac reagent and orthotolidine (Hematest^®) tablets were extremely sensitive, but yielded false-positive reaction rates of 72% and 76%, respectively on the 240 stool specimens compared. A modified guaiac test (Hemoccult^®) exhibited a false-positive rate of 12%. Of the 27 patients entering the study due to positive guaiac or Hematest screening tests, 17 (63%) were not bleeding. Hemoccult, approximately 1/4 as sensitive as guaiac and Hematest, could miss lesions with low rates of bleeding unless multiple stools were tested. While barium had no effect, iron therapy or laxatives tended to lower both false-positive and false-negative reactions for all reagents. A positive Hemoccult test usually indicated significant gastrointestinal bleeding and would appear to be the test of choice provided at least 3 stools are tested to minimize false-negative results.Supported by a Medical Investigatorship (Dr. Ostrow) and Gastroenterology Training Grant (Dr. Morris) from the U.S. Veterans Administration.     

Yield of dual endoscopy for positive fecal occult blood test

OBJECTIVES: Dual endoscopy is frequently performed on the same day in patients whose stools are found to be positive on fecal occult blood testing (FOBT). This is often done to localize the potential sources of GI bleed. The diagnostic yield of same day dual upper endoscopy (EGD) and lower endoscopy (colonoscopy) for the detection of positive FOBT is uncertain. In the era of cost-efficient medical practice, we investigated whether a more evidence-based and structured approach could be used to guide physicians to the workup of patients who present with positive FOBT. METHODS: We performed a retrospective analysis of 309 patients, and 260 patients from this population met our inclusion criteria. Inclusion criteria included FOBT without acute GI hemorrhage, hematochezia, or melena. Patients were required to have had EGD and colonoscopy within the same day (<24 h). RESULTS: Of 260 patients, a total of 135 (52%) patients had positive findings on colonoscopy and a total of 42 (16.1%) patients had positive findings on EGD. Sixteen (6.1%) had positive EGD and negative colonoscopy; 109 (42%) had positive colonoscopy and negative EGD; and 26 (10%) had positive findings on both EGD and colonoscopy. CONCLUSIONS: Colonoscopy should be chosen as the initial procedure of choice in the evaluation of patients who present with positive FOBT. Same day dual endoscopy does not seem to be cost-effective.     

Impact of fecal occult blood on obscure gastrointestinal bleeding:Observational study

AIM: To elucidate the association between small bowel diseases(SBDs) and positive fecal occult blood test(FOBT) in patients with obscure gastrointestinal bleeding(OGIB).METHODS: Between February 2008 and August 2013, 202 patients with OGIB who performed both capsule endoscopy(CE) and FOBT were enrolled(mean age; 63.6 ± 14.0 years, 118 males, 96 previous overt bleeding, 106 with occult bleeding). All patients underwent immunochemical FOBTs twice prior to CE. Three experienced endoscopists independently reviewed CE videos. All reviews and consensus meeting were conducted without any information on FOBT results. The prevalence of SBDs was compared between patients with positive and negative FOBT.RESULTS: CE revealed SBDs in 72 patients(36%). FOBT was positive in 100 patients(50%) and negative in 102(50%). The prevalence of SBDs was significantly higher in patients with positive FOBT than those with negative FOBT(46% vs 25%, P = 0.002). In particular, among patients with occult OGIB, the prevalence of SBDs was higher in positive FOBT group than negative FOBT group(45% vs 18%, P = 0.002). On the other hand, among patients with previous overt OGIB, there was no significant difference in the prevalence of SBDs between positive and negative FOBT group(47% vs 33%, P = 0.18). In disease specific analysis among patients with occult OGIB, the prevalence of ulcer and tumor were higher in positive FOBT group than negative FOBT group. In multivariate analysis, only positive FOBT was a predictive factors of SBDs in patients with OGIB(OR = 2.5, 95%CI: 1.4-4.6, P = 0.003). Furthermore, the trend was evidentam on g patients with occult OGIB who underwent FOBT on the same day or a day before CE. The prevalence of SBDs in positive vs negative FOBT group were 54% vs 13% in patients with occult OGIB who underwent FOBT on the same day or the day before CE(P = 0.001), while there was no significant difference between positive and negative FOBT group in those who underwent FOBT two or more days before CE(43% vs 25%, P = 0.20).CONCLUSION: The present study suggests that positive FOBT may be useful for predicting SBDs in patients with occult OGIB. Positive FOBT indicates higher likelihood of ulcers or tumors in patients with occult OGIB. Undergoing CE within a day after FOBT achieved a higher diagnostic yield for patients with occult OGIB.