Evaluation of rapid identification method for Mycobacterium tuberculosis complex using the immunochromatographic slide test kit

Capilia TB, a lateral flow immunochromatographic slide test kit for directly identifying Mycobacterium tuberculosis complex (MTC), was evaluated by using culture-positive specimens from Mycobacteria Growth Indicator Tubes (MGIT). Sputum specimens from patients suspected of having tuberculosis were treated with NALC-NaOH and cultivated in MGIT960. Liquid specimens were collected from the positive tubes and directly inoculated with Capilia TB. Liquid specimens were also directly tested with AccuProbe. Of the organisms isolated from the 100 MGIT positive tubes, M. tuberculosis complex was identified in 49 (49%) tubes with Capilia TB and not identified in 51 (51%) with Capilia TB. Mycobacterium avium-intracellulare complex (MAC) was identified in 46 (46%) with AccuProbe MAC and other acid-fast bacteria were identified in 5 (5%) by DNA-DNA hybridization method. There were one tube in which M. tuberculosis complex was detected with Capilia TB and M. tuberculosis complex was not detected with AccuProbe MTC, but no tubes in which M. tuberculosis complex was detected with AccuProbe MTC and M. tuberculosis complex was not detected with Capilia TB. Capilia TB is excellent in sensitivity and specificity and very suitable for rapid diagnosis of tuberculosis and is considered to contribute to public health intervention measures taken for the tuberculosis control in Japan.     

Evaluation of the GonoGen II kit for rapid identification of Neisseria gonorrhoeae using monoclonal antibody directed at gonococcal outer membrane protein 1

The Gonogen II test for rapid identification of Neisseria gonorrhoeae (Gonococcus, GC) was evaluated. The test is based on a colorimetric reaction with monoclonal antibody to GC outer membrane protein 1. Of the 50 clinical isolates of GC, 49 isolates tested positive and only one strain tested negative. Other Neisseria. spp, H. influenzae, H. parainfluenzae, E. corrodens, M. catarrhalis, and A. baumannii showed negative test results. Non-Neisseriae. spp, such as S. aureus. P. aeruginosa, E. faecalis, and E. coli also showed negative test results. No cross-reactivity was found between GC and other Neisseriae. spp or non-Neisseriae. spp. In a mixed suspension of GC and all of non-Neisseriae. spp as mentioned above, the GonoGen II test was positive. The specificity and sensitivity of the test for the identification of GC were 98% and 100%. The minimum limit of detection of GC was > or = 1 x 10(5) cfu/mL. Decision making based on the test result is possible within 10 minutes. These findings also suggest that the test does not require pure GC. The GonoGen II test appears to be a reliable, quick and easy-to-use assay, and also to not require viable GC. Thus GonoGen II is shown to be a very useful test for the identification of GC.     

Evaluation of an immunochromatography test kit for rapid diagnosis of influenza

We assessed the sensitivity and specificity of the Capilia Flu AB rapid diagnosis kit for influenza that utilizes the immunochromatography method. Tested were 114 influenza like illness patients in the 2001/2002 influenza season. We used Capilia Flu AB and Infu A . B Quick, a rapid diagnosis kit based on enzyme immunoassay. As laboratory confirmation tests, influenza virus isolation and polymerase chain reaction (PCR) were done. Those patients with positive results from virus isolation or PCR were regarded as influenza patients. The sensitivities of nasal swab, pharyngeal swab, and nasal wash specimens were 82.8%, 80.0%, and 75.0%, respectively. The specificities of nasal swab, pharyngeal swab, and nasal wash specimens were 95.3%, 93.9%, and 100%, respectively. A total of 20 patients displayed different results in comparison of their nasal and pharyngeal swabs: 15 patients were positive with the nasal swab but negative with the pharyngeal swab and 5 patients were negative with the nasal swab but positive with the pharyngeal swab. Nasal swab would seem to be preferable in terms of sensitivity. The sensitivity and specificity of Capilia Flu AB were a little higher than those of Influ A . B Quick, but with no significant difference. The one-step operation of Capilia Flu AB is easier than the four steps required by Influ A . B Quick, but the time required to make a diagnosis is the same. No significant age related difference in the effectiveness of the kits was found. The Capilia Flu AB rapid diagnosis kit is useful in clinical practice because it has good sensitivity (about 80%) and specificity (about 90%), and it is easy to use.     

A penicillinase test incorporated in the rapid carbohydrate fermentation method for rapid detection of beta-lactamase producing Neisseria gonorrhoeae

A modification of the acidometric (phenol red) test for penicillinase producing N. gonorrhoeae was incorporated into the rapid fermentation method for rapid screening and identification of PPNG strains. Two hundred and twenty-four non-penicillinase-producing N. gonorrhoeae, 55 penicillinase-producing N. gonorrhoeae, 87 N. meningitidis and 89 N. lactamica were included in this study. Results of the modified test were comparable with the iodometric and penicillin disk diffusion susceptibility and were obtainable within 1 to 5 minutes.     

一种A型流感病毒NP抗原快速检测试剂的建立

目的建立一种适合现场检测需要的A型流感快速诊断试剂。方法以自制的抗A型流感(FluA)病毒核蛋白(NP)单抗为原料,建立快速检测A型流感病毒的双抗体夹心酶免疫渗滤试验,并对其灵敏度和特异性进行了初步评价。结果该试剂对不同地区流行的各种亚型的A型流感病毒株均有较高的反应性,而对非FluA病毒株无交叉反应。比较该试剂与BD公司的两种流感快速诊断试剂,发现该试剂对随机选取的3株FluA病毒的检测分析灵敏度高出Directigen EZ Flu A试剂5~125倍,对2株FluA病毒的分析灵敏度高出Directigen Flu A试剂约20倍。另外,用该试剂对57份含漱液标本和170份动物拭子标本进行检测,结果显示:本试剂的灵敏度(>85%)和特异性(>95%)均优于当前主流的商品化A型流感快速诊断试剂。结论利用抗FluANP单抗为原料建立了A型流感快速诊断试剂,该试剂的应用无需任何专用仪器,操作简便快速,可满足现场检测需要。     

Evaluation of rapid urinary antigen test kit for Streptococcus pneumoniae in children with pneumonia or meningitis

We evaluated rapid urinary antigen test kit for Streptococcus pneumoniae (Binax NOW S. pneumoniae) in 85 inpatients between February 2002 and November 2002. Diseases of patients were pneumonia in 82 and meningitis in 3. The age range of the patients was from 4 months to 14 years. We studied urinary antigen assay and culture of nasopharyngeal swab in all patients. Three infants with meningitis were measured liquor by the kit. Two infants with meningitis due to S. pneumoniae showed positive reactions in urine and liquor, but result of 1 infant with meningitis due to Haemophilus influenzae was negative. Of 82 patients with pneumonia, S. pneumoniae was isolated from 52 patients and the urinary antigen test was positive in 39. Thirty-eight patients were isolated S. pneumoniae in 39 positive patients and 14 children were isolated it in 44 negative patients. Sensitivity in this test kit was 73.1% and specificity was 96.8%. This test is useful for children as well as adults.     

分枝杆菌菌种快速荧光初步鉴定方法的研究

目的　使用液体培养基,建立一种分枝杆菌(Mycobacterium)菌种初步鉴定的非放射快速荧光检测法。方法 应用自制的非放射荧光检测管,利用水溶性对硝基苯甲酸(PNitro benzoic Acid,PNB)和噻吩-2-羧酸肼(2-Thiophene carborylic acid hydrazide,TCH)对15株分枝杆菌标准菌株和78株分枝杆菌临床分离菌株做体外抑菌试验,确定其在菌群鉴定试验中的应用浓度。结果 PNB的应用浓度为100μg/ml,可有效地区别结核杆菌复合群与非结核分枝杆菌;TCH的应用浓度为2.5μg/ml,可有效地区别结核分枝杆菌和牛分枝杆菌。菌群鉴定结果7～10d可得到报告。结论 本法经济实用,并将分枝杆菌菌群鉴定结果报告时间由传统的LJ方法的28d缩短为7～10d。     

Evaluation of direct and rapid identification of group A streptococci from throat swabs by Culturette 10-Minute Group A Strep ID test kit

The Culturette Brand 10-Minute Group A Strep ID test kit (Marion Scientific, Division of Marion Laboratories, Inc., Kansas City, Mo.) was evaluated for its sensitivity and specificity in identifying the group A streptococci directly from 96 throat swabs, against the conventional culture method and serological grouping test. Our results indicated that the rapid test kit and conventional method are 93.8% accurate; percent sensitivity and specificity of the rapid test was 80.6% and 100%, respectively. None of the false-positive observed in rapid test kits occurred with the heterogeneous microorganisms. More than 8 X 10(4) colony forming unit per swab was required for the positive latex agglutination of the test kit. Since the Culturette method is simple to perform and correctly identifies group A streptococcal antigen, and also required no special instruments, it appears to be applicable in hospital laboratories and outpatients clinics.     

PCR测序和基因芯片快速鉴定分枝杆菌菌种的应用研究

目的 评价2种分枝杆菌菌种快速鉴定方法的临床应用价值。方法 分别用16S～23S rDNA转录间隔序列（ITS）PCR-直接测序和基于16S rRNA基因的基因芯片检测21株分枝杆菌标准菌株和50株临床分离株。结果 21株分枝杆菌标准株中,ITS PCR测序法将18株准确鉴定到种,结核分枝杆菌、非洲分枝杆菌菌株只能鉴定到结核分枝杆菌复合群,海分枝杆菌无法鉴别是海分枝杆菌还是溃疡分枝杆菌;芯片法正确鉴定16株,1株胃分枝杆菌鉴定为堪萨斯分枝杆菌,3株不在芯片检测范围内。50株临床菌株中, 47株2种方法结果一致,1株不在芯片检测范围内。结论 基因芯片鉴定分枝杆菌快速、特异,准确性高,临床常规开展应用需要进一步研究。     

A rapid polymerase chain reaction based method for identification of the Anopheles dirus sibling species

A simple polymerase chain reaction (PCR) based method was developed to differentiate the Anopheles dirus, species A, B, C and D in Thailand using specific primers designed from species specific sequences. The PCR protocol was optimized to obtain products of 120 bp, 75 bp, 60 bp and 172 bp for species A, B, C and D, respectively. This method used a cocktail of four primer sets to identify these An. dirus sibling species. The method is very sensitive as only a small portion of mosquito was required allowing the rest of the mosquito to be used for other analyses. Specimens also kept for up to 14 years could be analyzed unambiguously from either larvae or adult. This method is advantageous over other PCR-based methods for identification of malaria vectors because it does not require any specific DNA extraction. A mosquito specimen was homogenized in 1x PCR buffer, then the supernatant directly used for PCR identification, allowing a large number of samples to be processed at the same time. It provides a simple and rapid practical method for screening An. dirus species, which is essential in malaria vector epidemiological studies in Southeast Asia.     

一种唾液快速检测HIV-1/2型抗体试剂的现场评价

目的对一种唾液快速检测艾滋病病毒Ⅰ/Ⅱ型(HIV-1/2)抗体试剂进行现场评价,考核其现场使用的敏感性和特异性,以及与血液HIV-1/2抗体检测试剂的一致性。方法采集247例已知HIV感染者、1 090例正常献血人员、60例患有其它疾病的患者(包括孕妇、肿瘤患者、一般疾病患者),以及109例HCV感染者和119例未知HIV感染状况的吸毒人员的唾液标本,现场使用Vanguard OMTTM唾液HIV-1/2抗体快速检测试剂盒(CalypteBiomedical生产)进行检测,同时平行采集上述人群的血液标本,使用Vironostika HIV Uni-FormⅡplus O(BioMerieux生产)进行对比测试。结果247例已知HIV感染者中,247例唾液标本HIV-1/2型抗体检测均为阳性。1 259例血液酶联免疫吸附试验(ELISA)检测HIV抗体阴性人群中,1 257例唾液检测为阴性,2例为阳性。119例吸毒人员中,28例血液标本HIV阳性中,唾液标本检出27例。91例HIV阴性中检出阴性90例。该唾液HIV抗体快速检测试剂,敏感性为99.64%,特异性为99.78%。与ELISA检测的一致性为99.75%。结论唾液HIV-1/2型抗体检测试剂与现行的血液ELISA检测结果相近。唾液标本的采集方便而且危险性小,推荐在采血较困难的人群、基层医疗机构、VCT门诊等,可考虑使用唾液HIV-1/2型抗体快速检测试剂进行HIV抗体初筛检测。     

某口腔黏膜渗出液HIV-1／2型抗体检测试剂现场使用效果

目的对某国产口腔黏膜渗出液艾滋病病毒I／Ⅱ型（HIV-1／2）抗体检测试剂进行评价,考核其灵敏度与特异度。方法平行采集353例女性性工作者血液及口腔黏膜渗出液标本,分别使用血液HIV抗体检测试剂和某口腔黏膜渗出液（OMT）HIV-1／2型抗体检测试剂进行现场检测,对比两种检测试剂的检测结果。结果经蛋白免疫印迹试验（wB）检测,62例血液HIV抗体阳性者中,61例OMT检测结果为阳性,该试剂灵敏度为98．39％;291例血液HIV抗体阴性者中,12例OMT检测结果为阳性,263例结果阴性,16例结果为不确定。排除16例OMT结果为不确定的样本后,275例HIV阴性者中,263例OMT结果为阴性,该试剂特异度为95．64％。结论口腔黏膜渗出液HIV-1／2检测试剂灵敏度与特异度均较高,可以应用于现场检测中。     

A diagnostic kit for rapid microenzyme linked immunosorbent assay of paragonimiasis

With a diagnostic kit for paragonimiasis we recently developed, 112 active paragonimiasis cases were examined and 111 (99.1%) of them showed positive reaction. Sera of 100 healthy persons all showed negative reaction, while 2.3% (3/130) of the patients with other parasitic diseases showed a week cross reaction. Sera of 40 cases with non-parasitic pulmonary diseases also showed negative reaction. The reciprocal titre of cases of paragonimiasis in terms of geometrical mean (GMRT) versus that of normal person was 1396 to 21 (P less than 0.0001). The reproduction and stability of this kit was satisfactory and no significant changes were noted when being kept in room temperature for 12 weeks or being treated with heat (37 degrees C 30', 56 degrees C 30', 64 degrees C 30', 100 degrees C 1', 2', 3', in water bath). When the antigen was treated in 100 degrees C water bath for 30', the OD value obtained with positive control serum showed a slight decrease, but OD value of the positive specimen was still 2.1 times higher than that of negative specimen. There was no significant difference whether the antigen was lyophilized or not. When the antigen was purified by sephadex G 100 gel column, the G100-1 portion showed higher antigenic activity and specificity, but it was not as sensitive as the crude antigen.     

Conjugation of plasmids of Neisseria gonorrhoeae to other Neisseria species: potential reservoirs for the beta-lactamase plasmid

The discovery that penicillinase production in Neisseria gonorrhoeae was plasmid mediated and the spread of the beta-lactamase encoding plasmids in gonococcal isolates since 1976, raise the possibility that a nonpathogenic indigenous bacterium could serve as a reservoir for these plasmids. We initiated studies to define the ability of commensal Neisseria species and Branhamella catarrhalis strains, as well as strains of the pathogen Neisseria meningitidis, to serve as recipients in conjugation with Neisseria gonorrhoeae. We found that with N. gonorrhoeae as the donor, 3 of 5 Neisseria cinerea, 2 of 5 Neisseria flava, 0 of 1 Neisseria flavescens, 1 of 3 Neisseria subflava, 0 of 6 B. catarrhalis, 0 of 7 Neisseria lactamica, 1 of 5 Neisseria mucosa, 1 of 7 Neisseria perflava/sicca, and 0 of 13 N. meningitidis strains gave detectable conjugation frequencies (greater than 10(-8). N. cinerea was the only species found to maintain the gonococcal conjugal plasmid (pLE2451). A N. cinerea transconjugant containing pLE2451 was observed to transfer both the beta-lactamase plasmid and pLE2451 to N. gonorrhoeae at high frequency.     

A haemagglutination inhibition test kit for routine analysis of erythropoietin

Summary A commercially available haemagglutination inhibition test kit for routine analysis of erythropoietin was shown to be unable to detect elevated levels of serum Epo.