多仪器联合分析尿液的应用价值

目的:探讨干化学分析、UF-100尿有形成分分析与DIASYS沉渣镜检分析联合检测尿液的应用价值。方法:用尿干化学分析仪MiditronM、UF-100型尿液分析仪、DIASYS R/S 2003沉渣分析仪分别对390例随机尿液标本进行检测。结果:以DIASYSR/S 2003沉渣分析结果为标准,干化学法与DIASYS镜检法相比,测定红细胞阳性符合率为92.68%,假阳性为13.96%,假阴性为7.32%;测定白细胞阳性符合率为58.91%,假阳性为9.58%,假阴性为41.09%;UF-100与DIASYS相比,检测红细胞阳性符合率为82.93%,假阳性为7.47%,假阴性为17.07%;测定白细胞阳性符合率为81.40%,假阳性为12.26%,假阴性为18.60%;检测上皮细胞、小园上皮细胞、管型、结晶和类酵母菌阳性符合率较低,分别为69.09%、60.53%、68.18%、78.95%、57.14%。390例尿标本中干化学法白细胞、红细胞、蛋白及亚硝酸盐均阴性的176例标本中,UF-100检测红细胞阳性14例,白细胞阳性19例,DIASYS检出红细胞阳性5例,白细胞阳性11例。结论:UF-100型尿沉...     

尿液菌落计数在儿童泌尿感染筛查中的应用

目的检验和比较尿液菌落计数在筛选儿童泌尿系统感染中的可靠性。方法收集儿童中段尿液,10μL进行细菌培养和菌落计数,剩余样本进行干化学分析,主要进行沉渣镜检、亚硝酸盐和白细胞酯酶检测。结果共检测中段尿液标本112份,其中32例培养出有意义细菌,阳性率为28.6%。尿沉渣镜检、干化学分析的敏感性分别为68.8%和78.1%,特异性分别为92.5%、90.0%。另有7例培养阳性,干化学分析阴性,假阴性为21.9%;6例沉渣镜检阳性,培养阴性,假阳性率7.5%;沉渣镜检、干化学分析的阳性预示值分别为78.6%和75.8%。结论尿液细菌培养和菌落计数在筛选儿童泌尿感染的敏感性要明显优于尿沉渣镜检和干化学分析,在儿童泌尿系统感染筛查中起到重要作用。尿沉渣镜检和干化学分析因为敏感性不足、结果易受到感染类型影响。尿液菌落计数可作为儿童泌尿系统感染检测的重要指标。     

FUS-100尿沉渣分析仪在住院患者尿路感染筛检中的应用

目的 探讨FUS-100全自动尿沉渣分析仪(简称FUS-100)中的细菌和酵母定量计数在筛查住院患者尿路感染时的价值.方法 用定量细菌培养法和FUS-100检测505例疑似泌尿系统感染患者清洁中段尿标本.结果 505份尿标本培养阳性192份,阳性率为38.0％,其中36份标本有两种细菌生长,共分离出228株菌,革兰阳性球菌30株(13.2％),革兰阴性杆菌108株(47.4％),真菌90株(39.4％).以尿细菌计数≥23.72/μL、酵母计数≥0.65/μL为感染阳性标准,与中段尿培养相比较,FUS-100细菌定量计数的敏感性为85.5％,特异性为89.5％,阳性似然比为8.14,阴性似然比为0.16;酵母定量计数的敏感性为80.4％,特异性为97.2％,阳性似然比为28.71,阴性似然比为0.20.结论 FUS-100定量计数尿细菌和酵母可用于住院患者尿路感染的快速筛查.     

不同检验方法在尿路感染诊断中的临床价值

目的探讨尿干化学分析法与尿沉渣分析法在诊断患者尿路感染中的临床价值。方法收集2017年9月至2018年7月于重庆市黔江中心医院就诊的疑似尿路感染患者尿液标本400份,分别利用尿干化学分析及尿沉渣分析法检测标本,比较不同检测分析法的灵敏度、特异度、阳性预测值及阴性预测值。结果尿干化学分析法检测阳性率为42.25%(169/400),尿沉渣分析法检测阳性率为32.75%(131/400),尿沉渣分析法检测阳性率明显低于尿干化学分析法(X~2=7.7010,P=0.0070),差异有统计学意义。尿干化学分析法检测白细胞计数阳性率为25.25%(101/400)、亚硝酸盐阳性率为17.00%(68/400);尿沉渣分析法检测白细胞计数阳性率为24.25%(97/400),细菌计数阳性率为8.50%。尿沉渣分析法检测白细胞计数阳性率与尿干化学分析法比较,差异无统计学意义(X~2=0.1070,P=0.8060)。尿干化学分析法灵敏度为72.95%,特异度为90.67%,阳性预测值为89.35%,阴性预测值为75.76%;尿沉渣分析法灵敏度为57.97%,特异度为94.30%,阳性预测值为91.60%,阴性预测值为67.66%。尿干化学分析法检测的灵敏度及阴性预测值明显高于尿沉渣分析法(X~2=10.2660,P=0.0020;X~2=3.9930,P=0.0480),差异具有统计学意义。结论尿干化学分析法及尿沉渣分析法均有一定的临床诊断价值。可针对两种检测方法的联合应用进一步研究,以期提高尿路感染诊断的灵敏度及特异度。     

NASBA荧光分子信标技术定量检测丙型肝炎病毒

建立NASBA荧光分子信标探针检测技术,并对国家HCV标准品、人工构建HCVRNA野生株及HCV抗体阳性不同人群进行检测。实验结果:该方法检测HCV的灵敏度为103拷贝ml血清,阴性参比品的符合率为100%;检测的线性范围为103拷贝～109拷贝ml血清;精密性(CV值)小于6%,在HCV抗体阳性人群中HCVRNA的检出率在45%～65%之间。结论:该方法在HCVRNA临床定量检测中具有良好的灵敏度、特异性、重复性与实用性。     

泌尿系感染细菌L型培养结果分析

尿路感染是临床最常见的感染之一 ,而细菌 L型又是尿路感染较常见的细菌之一。L型细菌培养国内外已开展多年 ,我科近三年在作普通细菌培养的基础上 ,同时增设了 L型细菌培养 ,现将我们所作的 118例尿液标本培养鉴定结果分析报告如下。1　材料与方法1.1　材料　高渗增菌液 ,由武汉市临床检验中心提供。L 型培养基 ,购自浙江省军区后勤部卫生防疫检验所。细胞壁染色液 :10 %鞣酸、5 %龙胆紫。标本来源 :118例标本全部采自本院各科住院患者中段尿。1.2　方法1.2 .1　用无菌方法吸取 0 .1ml尿液于高渗增菌液内进行增菌培养 ,另取 0 .1ml尿液于…     

实时荧光PCR在呼吸道感染耐甲氧西林金黄色葡萄球菌检测中的临床应用

目的评价实时荧光PCR(RT-PCR)用于检测呼吸道感染耐甲氧西林金黄色葡萄球菌(MRSA)中的方法学特性,为临床快速诊断呼吸道MRSA定植或感染提供可靠循证依据。方法通过RT-PCR技术对痰液标本中金黄色葡萄球菌(SA)特异性核酸酶编码基因nuc和MRSA的特异性耐药基因mec A进行定量检测,并同时以细菌培养、鉴定和MRSA耐药表型确诊实验作为参考方法,评价其灵敏度、特异度、阴阳性预测能力;用10倍梯度稀释法配制已知标准菌株菌悬液评估RT-PCR的最低检出限。结果 RT-PCR法较细菌培养法对MRSA检测的总符合率为97.5%,检测SA的敏感度为97.2%、特异度为98.2%、阳性预测值为92.1%、阴性预测值为99.4%,检测甲氧西林耐药性的敏感度为100%、特异度为97.7%、阳性预测值为85.2%、阴性预测值为100%;RT-PCR对nuc基因和mec A基因的最低检出限均为103/m L。结论RT-PCR法与细菌培养法对于检测MRSA差异无统计学意义,且灵敏度优于后者,是用于临床快速排除性筛查呼吸道感染MRSA的较佳检测方法。     

复合探针荧光定量PCR法检测布鲁氏菌的实验研究

目的:建立用复合探针荧光定量PCR快速检测布鲁氏菌的方法。方法:研究根据BSCP31基因编码31KDa的布鲁氏杆菌表面蛋白的核苷酸序列设计特异引物,通过PCR法的特异性、灵敏度和重复性研究,建立了复合探针荧光定量PCR检测布鲁氏菌的方法,用于布鲁氏菌病的筛选和诊断。结果:结果表明该检测方法的特异性为100%,最低可检出10个拷贝的质粒DNA分子,可对1×101-1×106拷贝范围内的模板进行定量,最低可检测至1×102CFU/ml细菌。该方法的精密度好,阳性质控品和阴性质控品不同时间测定三次及同一时间五次重复实验结果CV值均小于5%。结论:本研究建立的复合探针实时荧光定量PCR检测布鲁氏杆菌的方法,可对布鲁氏病原菌进行快速检测,对布病的筛选和确诊具有重要意义。     

尿液常规干化学法测定影响因素的探讨

目的：通过分析尿液常规检验中标本采集后放置时间和标本中污染细菌后对结果的影响,来探讨尿液分析的标准化。方法：按全国临床检验操作规程（第三版）的推荐方法在1 h之内进行尿液干化学分析, 根据结果分为阳性标本组,阴性标本组,阴性标本接种大肠埃希菌组和阴性标本接种粪肠球菌组,然后放置在室温（约20℃）,每隔1 h 进行尿液干化学分析直至留取标本后5 h。结果：尿液干化学分析结果受多种影响因素,阴性标本接种大肠埃希菌后尿隐血、亚硝酸盐产生假阳性,阳性标本室温放置后尿胆原、蛋白质、白细胞、维生素C阳性减弱或产生假阴性。结论：在实际工作中必须遵照标准化的操作规程的要求,正确地留取标本并及时送检,排除多种影响因素干拢,才能保证结果的准确性,更好地为临床服务。     

复合探针荧光定量PCR法检测布鲁氏菌的实验研究

目的：建立用复合探针荧光定量PCR快速检测布鲁氏菌的方法。方法：研究根据BSCP31基因编码31KDa的布鲁氏杆菌表面蛋白的核苷酸序列设计特异引物,通过PCR法的特异性、灵敏度和重复性研究,建立了复合探针荧光定量PCR检测布鲁氏菌的方法。用于布鲁氏菌病的筛选和诊断。结果：结果表明该检测方法的特异性为100％,最低可检出10个拷贝的质粒DNA分子,可对1×10^1-1×10^6拷贝范围内的模板进行定量,最低可检测至1×10^2CFU／ml细菌。该方法的精密度好,阳性质控品和阴性质控品不同时间测定三次及同一时间五次重复实验结果CV值均小于5％。结论：本研究建立的复合探针实时荧光定量PCR检测布鲁氏杆菌的方法,可对布鲁氏病原菌进行快速检测,对布病的筛选和确诊具有重要意义。     

Simple Disposable Method for Quantitative Cultures of Urine

A disposable kit was tested as a means of detecting significant bacteriuria by quantitative culture of urine. The total error in 3,563 specimens tested by five investigators was less than 1%. The method was very effective in differentiating significant bacteriuria, i.e., more than 100,000 bacteria per ml of urine from uninfected urine. In specimens from patients with urinary tract abnormalities who had mixed bacterial flora, the absolute numbers obtained with the dip-inoculum method had a 10% variation when compared to results obtained by calibrated loop or dilution pour plate methods. Therefore, the main utility of the kit is for screening and following patients after therapy. A significant delay in time between inoculation of the medium in the kit with the freshly voided urine and incubation of the kit to promote growth did not affect the reliability of the kit as a method of doing quantitative urine cultures to detect bacteriuria.     

Quantitative Urine Culture by Surface Drop Method

A simple drop method for quantitative urine culture was developed and tested in comparison with standard methods for bacterial urinary counts. In a group of 452 urines all yielding Escherichia coli, 74 showed counts of more than 100,000 colonies, and 16 showed counts between 10,000 and 100,000 colonies per ml. Of these 90 urines, 3 of the 16 in the doubtful group were false negative with the drop method. Another 7 urines in the total number of 452 showed discrepancies, but, because all would have been repeated, the second urine sample would have corrected the primary result. The ease and cleanliness of the method render it a suitable technique for screening normal and patient populations. The method was applied on a population sample of 1,330 persons from whom unwashed mid-stream urine was collected and yielded figures comparable with results published in the literature. The method discriminates between steps of 10-fold difference, whereas more accurate count methods show a standard error of +/-25% and are reliable in a double dilution series.     

A Comparative Study of the Triphenyltetrazolium Chloride (Uroscreen) Test and Conventional Methods for the Detection of Bacteriuria

Acute urinary tract infection may be preceded by and active pyelonephritis may be associated with asymptomatic bacteriuria. Treatment of asymptomatic bacteriuria may prevent or arrest active, chronic pyelonephritis and its sequelae. Consequently, there is a need for a reliable and simple screening procedure to detect asymptomatic bacteriuria in large segments of the population.The reliability and practicability of tests advocated for the detection of bacteriuria, including the new chemical triphenyltetrazolium chloride (T.T.C.) (Uroscreen) test, were evaluated. Reliability was assessed by correlating results of these tests with bacterial counts of tested urines. Significant bacteriuria is defined as the presence of 100,000 or more organisms per ml. of urine.The T.T.C. (Uroscreen) test was positive in 92.5% of cases of bacteriuria; there were 7.5% false-negative and 2.8% false-positive results. Bacteria on Gram-stained smear were found in 95.5% of the cases of bacteriuria and in 14.6% of those with non-infected urine; pyuria (more than three leukocytes per high-power field), in 60% of those with bacteriuria and in 15.9% of those with presumably non-infected urine. Bacteria were conspicuous in the urinary sediment in 91.1% of cases of bacteriuria and in 3.7% of presumably non-infected urines.The T.T.C. (Uroscreen) test fulfilled the criteria for a reliable and simple screening procedure. It should be used concomitantly with other screening tests when the urine is examined routinely.     

Application of urinary mutagen testing to detect workplace hazardous exposure and bladder cancer

The objectives of this biochemical epidemiologic case-control study were to evaluate urinary mutagen testing for occupational exposure assessment, and for possible screening for bladder cancer in the workplace. Thirty-seven patients (19 bladder cancer cases and 18 controls) completed a questionnaire. Two urine samples, i.e. a work sample taken while at work, and a home sample, were requested from each patient. Twenty-six patients (17 cases and 9 controls) gave a total of 47 24-h urine samples for mutagenicity testing by the Ames test. A positive Ames test was found to be associated significantly with current occupation with hazardous exposure (odds ratio = 3.7, 95%CI 1.1–12.9), and non-significantly with bladder cancer (odds ratio = 1.8, 95%CI 0.5–7.1). Our results show that the urinary Ames test has the potential of being used as a surveillance for current workplace hazardous exposure (sensitivity = 52%, specificity = 77%, positive predictive value = 72%, negative predictive value = 59%, positive likelihood ratio = 2.3), but not as a screening test for bladder cancer cases (sensitivity = 42%, specificity = 71%, positive predictive value = 3%, negative predictive value = 98%, positive likelihood ratio = 1.5).     

Validity and cost-effectiveness of the Gonozyme test in the diagnosis of gonorrhea.

Although bacterial culture is considered to provide the most definitive diagnosis of gonorrhea, it has limitations when specimens must be transported long distances. A study was carried out to evaluate the validity and cost-effectiveness of an alternative method of diagnosing gonorrhea, the Gonozyme test, a commercially available enzyme immunoassay. Urogenital specimens from 100 men and 100 women with symptoms suggestive of or a history of exposure to gonorrhea were tested for the presence of Neisseria gonorrhoeae by means of bacterial culture and for gonococcal antigen with the Gonozyme test. The specimens from the men were also examined by means of microscopy of Gram-stained smears. The sensitivity and specificity of the Gonozyme test with reference to culture results were 95.6% and 97.4% respectively in the men and 84.2% and 98.7% in the women. The predictive value of a positive result was 91.6% in the men and 94.1% in the women, and the predictive value of a negative result 98.6% in the men and 96.3% in the women. The cost-effectiveness of the Gonozyme test was higher than that of bacterial culture in this population, which had a high prevalence rate of gonorrhea (23% in the men and 19% in the women). The Gonozyme test would be an adequate alternative to culture for the diagnosis of gonorrhea and contact tracing in areas far from diagnostic laboratories.     

The Triphenyl Tetrazolium Chloride (Uroscreen) Test Alone and in Combination with the Gram Smear as a Screening Procedure for Significant Bacteriuria in Hospital Patients

Of 725 specimens of urine examined by the triphenyl tetrazolium chloride (TTC) [Uroscreen], pour plate and calibrated loop procedures, 30% yielded bacterial colony counts greater than 100,000/ml.; a 100% correlation was obtained among the three methods. Of 539 urine specimens containing more than 100,000 bacteria/ml., 517 (94.06%) gave a positive TTC test.Because of the high correlation between the TTC test and bacterial quantitative counts, the method of TTC in conjunction with smears was adopted as a routine procedure. Specimens which were TTC-negative and smear-negative were discarded. Of 1227 specimens from hospital in-patients and 349 outpatients, 369 urines showed significant bacteriuria (337 from hospital in-patients and 32 from outpatients). There was complete correlation between the TTC test and smear. Of 337 isolations, 27 (8.02%) gave a negative TTC test but a positive smear.     

Rapid Detection of Gram-Negative Bacteriuria by Use of the Limulus Endotoxin Assay

The Limulus in vitro endotoxin assay was evaluated as a possible method for the prompt detection of significant gram-negative bacteriuria in children. This assay is capable of detecting endotoxin associated with intact cell walls of viable gram-negative bacteria as well as free endotoxin. Quantitative results are obtained following a 1-h incubation of Limulus lysate and 10-fold dilutions of otherwise untreated urine. A standard curve of Limulus activity and viable cell counts of Escherichia coli and Klebsiella pneumoniae in urine demonstrated that a positive Limulus reaction at a dilution of 1:100 or 1:1,000 indicated a colony count of at least 100,000 bacteria/ml. A positive Limulus reaction only from undiluted urine or at a dilution of 1:10 indicated less than 100,000 cells/ml. These experimental observations were confirmed by comparing the Limulus test with quantitative plate counts on 209 urine specimens from a mixed pediatric population. These results indicate that the Limulus assay is a simple, accurate method for rapid presumptive detection of gram-negative bacteriuria in patients where an immediate diagnosis is needed. This test would also seem promising for screening large patient populations for bacteriuria or for monitoring the effectiveness of treatment of urinary tract infections.     

Development and validation of a timed urinary collection system for use in the cat

The aim of the study was to develop and validate a feline urinary collection system for accurate 24 h urine output measurement and glomerular filtration rate (GFR) evaluation. We hypothesized that precise identification of urination time improves the accuracy of the collection system. In a group of nine cats, urinary volume and micturition times were repeatedly recorded for up to 48 h using purpose-built collection trays containing a temperature data logger. Collection time was determined both with and without using the data loggers on 22 occasions and agreement between estimated 24 h urine outputs obtained with the two calculation methods was evaluated. GFR was repeatedly measured by endogenous urinary creatinine clearance on three occasions. Twenty-four-hour urine output was measured in 98.5% of the attempted collections (300 cat-sampling days). Sensitivity and specificity of the detection system were 97.8% and 100%, respectively. Mean 24 h urine output was 12.4 ± 4.94 mL/kg/day and mean intra-cat between-days coefficient of variation (CV) was 16.6 ± 5.6% when data loggers were used. The absolute relative volume error between the two calculation methods ranged from 0% to 131%. Median absolute relative [interquartile range] error was 9.1% [3.25-19.8]. Bias was -1.3% and lower and upper limits of agreement were -39.7% and 35.2%, respectively. Mean estimated GFR was lower than previously reported with comparable urinary clearance methods (1.92 ± 0.37 mL/min/kg) and mean within-cat CV was 12 ± 6.9%. The system was simple in design, readily affordable, allowed normal micturition behaviour and reduced intra-animal variability in 24 h feline urine collection.