本文分析了我院1979年2月至1987年4月收治的50岁以上中、老年人革兰氏阴性杆菌肺炎61例。男性37例,女性24例。年龄50～86岁,平均61男。有一种或一种以上基础疾病者56例(91.8％),其中肺部疾病32例(57.1％);心血管疾病18例(31.2％);口腔和副鼻窦疾病6例(10.8％)。院内获得性感染20例(32.8％)。本病临床表现多不典型,缓慢起病52例(85.2％),咳嗽或轻微咳 This article analyzes 61 cases of Gram-negative bacilli pneumonia in the middle-aged and the elderly in our hospital from February 1979 to April 1987. 37 males and 24 females. Aged 50 to 86 years old, with an average of 61 men. There were 56 cases (91.8%) with one or more underlying diseases, including 32 cases of pulmonary disease (57.1%), 18 cases of cardiovascular disease (31.2%) and 6 cases (10.8%) of oral and paranasal sinus diseases. Nosocomial infections in 20 cases (32.8%). The clinical manifestations of this disease are atypical, slow onset in 52 cases (85.2%), cough or mild cough