Background： Direct ZN （Ziehl-Neelsen） sputum smear microscopy for diagnosis of TB （tuberculosis） has low sensitivity, especially in TB/HIV co-infected patients. Sputum concentration by bleach （NaOCI） with sedim...Background： Direct ZN （Ziehl-Neelsen） sputum smear microscopy for diagnosis of TB （tuberculosis） has low sensitivity, especially in TB/HIV co-infected patients. Sputum concentration by bleach （NaOCI） with sedimentation has been used to increase the sensitivity of sputum smear microscopy in many settings but with varying results. Objective： To determine whether bleach plus centrifugation significantly improves the detection of AFB （acid-fast bacilli） in ZN smear-negative sputum specimens. Methods： Three hundred and seventy sputum specimens were collected from new TB suspects attending a Nairobi referral district hospital and processed for direct microscopy using ZN technique and culture on Lowenstein Jensen Media. All smear-negative specimens were treated with 3.5% bleach and left to stand for 30 min before centrifugation. The bleach treated smears were processed and examined using ZN technique. Results： Of the 370 specimens, 200 （54%） were positive culture. The number of sputum samples that were smear-positive by direct ZN was 138 （37.2%）, with a sensitivity of 66%. After treatment of direct ZN smear-negative specimens with 3.5% bleach and centrifugation, the total number of AFB smear-positive samples increased to 171 with an increase in sensitivity of 66% to 81.1% （15.1%）. Conclusion： In this study, bleach with centrifugation significantly increased the yield of sputum smear microscopy. Further evaluation of these techniques in routine programmes is required especially in settings where the burden of TB/HIV is high.展开更多
尿液有形成分（urine formed elements）检查是尿常规检查中的重要组成部分，而尿沉渣检查或尿有形成分检查又采用多样化的检查方法，标准很不统一，参考区间也非常不一致，甚至相差悬殊。公认的尿沉渣离心镜检法，对尿量、离心条件、...尿液有形成分（urine formed elements）检查是尿常规检查中的重要组成部分，而尿沉渣检查或尿有形成分检查又采用多样化的检查方法，标准很不统一，参考区间也非常不一致，甚至相差悬殊。公认的尿沉渣离心镜检法，对尿量、离心条件、盖片、沉渣量、检查视野数量等存在要求高、费时、重复性差，而又不易定量，推广起来还有一定问题。在临床诊断和治疗、预后观察等方面，如果采用定量分析法，定量分析患者尿液中的有形成分变化情况，要比定性分析法更有应用价值，因此国内外都曾经推荐定量法来分析尿液中的有形成分。而我们最近的实验研究表明，离心法由于离心等各种因素的存在，并不是准确定量计数尿液中有形成分的最佳方法。展开更多
文摘Background： Direct ZN （Ziehl-Neelsen） sputum smear microscopy for diagnosis of TB （tuberculosis） has low sensitivity, especially in TB/HIV co-infected patients. Sputum concentration by bleach （NaOCI） with sedimentation has been used to increase the sensitivity of sputum smear microscopy in many settings but with varying results. Objective： To determine whether bleach plus centrifugation significantly improves the detection of AFB （acid-fast bacilli） in ZN smear-negative sputum specimens. Methods： Three hundred and seventy sputum specimens were collected from new TB suspects attending a Nairobi referral district hospital and processed for direct microscopy using ZN technique and culture on Lowenstein Jensen Media. All smear-negative specimens were treated with 3.5% bleach and left to stand for 30 min before centrifugation. The bleach treated smears were processed and examined using ZN technique. Results： Of the 370 specimens, 200 （54%） were positive culture. The number of sputum samples that were smear-positive by direct ZN was 138 （37.2%）, with a sensitivity of 66%. After treatment of direct ZN smear-negative specimens with 3.5% bleach and centrifugation, the total number of AFB smear-positive samples increased to 171 with an increase in sensitivity of 66% to 81.1% （15.1%）. Conclusion： In this study, bleach with centrifugation significantly increased the yield of sputum smear microscopy. Further evaluation of these techniques in routine programmes is required especially in settings where the burden of TB/HIV is high.
文摘尿液有形成分（urine formed elements）检查是尿常规检查中的重要组成部分，而尿沉渣检查或尿有形成分检查又采用多样化的检查方法，标准很不统一，参考区间也非常不一致，甚至相差悬殊。公认的尿沉渣离心镜检法，对尿量、离心条件、盖片、沉渣量、检查视野数量等存在要求高、费时、重复性差，而又不易定量，推广起来还有一定问题。在临床诊断和治疗、预后观察等方面，如果采用定量分析法，定量分析患者尿液中的有形成分变化情况，要比定性分析法更有应用价值，因此国内外都曾经推荐定量法来分析尿液中的有形成分。而我们最近的实验研究表明，离心法由于离心等各种因素的存在，并不是准确定量计数尿液中有形成分的最佳方法。
