[A prospective study on etiologic bacteria in 200 patients with pneumonia]

The etiologic agents in 200 patients with pneumonia were studied by the bacterial culture of sputums obtained from the protected single catheter brush or quantitative expectoration at one morning or three-morning expectoration. Two hundred patients were divided into 3 groups. Group 1 was Nosocomial pneumonia (NP patients). Group 2-1 and Group 2-2 were community acquired pneumonia (CAP patients). All cases in Group 1 and Group 2-2 suffered from significant underlying diseases while Group 2-1 did not. Gram-negative bacilli(GNB) were isolated from the specimens in Group 1 (87%) and Group 2-2 (75%), respectively. Pseudomonas (30.8%) and klebsiella (20.5%) were the predominant bacteria (in Group 1 and pseudomonas bacteria) in Group 1 and pseudomonas (27.3%), acinetobacter (23%) and kledsiella (18%) were the major etiologic agents in Group 2-2. The commonest pathogens in Group 2-1 were gram-positive cocci (75%), in which streptococcus (38%) and staphylococcus aureus (25%) were the dominant agents. Compared with Group 2, Group 1 suffered from more mixed bacteria and the agents presented severer drug-resistant. The prognosis was worse in Group 2-2 than in Group 2-1. The results showed that the GNB pneumonia was more common in the cases who had underlying disease, no matter whether the pneumonia was NP or CAP. These patients had more trouble on their antibiotic therapy. Thus it is important that doctors should use vigorous antibiotics timely while treating these patients' underying diseases.