痰涂片革兰氏染色在老年人呼吸机相关性下呼吸道感染中的应用价值

Diagnostic value of gram-stained sputum smear in elderly patients with ventilator-associated lower respiratory infection

目的探讨痰涂片革兰氏染色对老年人呼吸机相关性下呼吸道感染（VALIR）微生物学诊断的准确性及诊断价值。方法回顾性分析2009年6月至2011年6月入住我院重症监护病房（ICU）60岁及以上且机械通气〉48h患者368例，其中42例符合人选标准，即痰标本合格，且在痰培养及血培养中同时存在一致的病原微生物，共收集58株痰涂片及痰培养结果进行分析。结果痰涂片诊断G’菌及G菌敏感度分别为82．35％、78．05％，特异度分别为80．49％、82．35％，阳性预测值分别为63．64％、91．43％，阴性预测值分别为91．67％、60．87％，符合率分别为81．03％、79．31％。结论痰涂片革兰氏染色在VAI。IR病原学诊断中应用可靠，对早期指导选择抗生素具有一定的临床意义。

Objective To explore the diagnostic value of gram stained sputum smears in elderly patients with ventilator-associated lower respiratory infection （VALRI）. Methods 368 elderly patients undergoing mechanical ventilation over 48 hours in ICU were retrospectiely analyzed from Jun 2009 to Jun 2011. 42 patients fulfilled the inclusion criteria （with good quality sputa and presence of the same microorganism in sputum and blood cultures）. 58 gram-stained smears and sputum cultures were obtained and analyzed. Results The diagnostic sensitivity and specificity of Gram-positive bacteria and Gram negative bacteria by gram-stained smears were 82.35o/00 and 78.05~, 80.49~ and 82.35 %0, respectively. The positive and negative predictive value of Gram positive bacteria and Gram negative bacteria were 63.64o/00 and 91. 430/00, 91. 670/00 and 60. 87%, respectively. The coincidence rates in diagnosing Gram-positive bacteria and Gram negative bacteria were 81.03% and 79.31%, respectively. Conclusions Gram-stained sputum smear is reliable in diagnosing ventilator associated lower respiratory infection in elderly patients, and has a certain clinical significance in guiding to the selection of antibiotics.