Fluorescence Quantitative Polymerase Chain Reaction Detection Of Mcoplasma Pneumoniae In Throat Swab And Sputum Of Community-Aquired Pneumoniae Patients

Objective:The etiological study of community acquired pneumoniae is always the important subject. There are many problems about the etiological technology of CAP. Because most of the etiological studies about CAP are retrospective, primary antibiotics treatment in patients with CAP is empirical mostly. A rapid diagnositic method is required for prescription of effective antibiotics. Mycoplasma pneumoniae is a common cause of community acquired pneumoniae. Between 10 and 30% of all cases of community acquired pneumoniae can be attributed to this cell wall less pathogen and it seems to be increasing. And now it is about equal to streptococcus.pneumoniae. Both are nearly to 50% in CAP. Mycoplasma pneumoniae is not sensitive toβ-lactam antibiotics which are used most extensive for bacteria infection. It is sensitive to macrolide and fluoro-quinolone. But in Asia macroide-resistant Streptococcus.pneumoniae cases are more than 50%. The macrolide often use with other kind of antibiotics in the guide. In addition in rencent ears the incidence of fluoroquinolone-resistant S.pneumoniae has risen markedly. Furthermore fluoroquinolone-resistant Haemophilas influenzae has also emerged. So if there are some prise and rapid diagnosis methods, the antibiotics we chosen will be more accurate.Serological testing is currently the most common tool for the diagnosis of Mycoplasma pneumoniae infection. Rely on IgM reaching to the criterion or IgG being a four-fold rise or more in acute and convalenscent serum sample. However they provide only a retrospective diagnosis and the accuracy are likely affected by defect of immunity and recently infection of Mycoplasma pneumoniae. Nucleic acid amplification techniques that are belong to molecular biology were used to detect Mycoplasma pneumoniae. The advanced PCR based on traditional PCR are used like flurescence quantitative polymerase chain reaction (FQ-PCR). It integrated high sensitive of PCR and high specificity of DNA hybridization probe and high exact quantitation of spectrum technical. It give a fast consequence within 2 hours so provide help to clinical early treatment. This study detect the Mycoplasma pneumoniae in the swab and the sputum of the CAP patients by FQ-PCR. The swab is paired(acute and convalent swab). The qutity of Mycoplasma pneumoniae is rectified by the epithelium quantity that is observed under the low power magnification. The popurse is that investigate the difference between the swab and the sputum.and between the paired swabs, further probe into the early diagnosis value and clinical significance conbining with clinical characteristics.A total of 50 patients with X-ray-proxen community-acquired pneumo-niae were prospectively included in a hospital-based study in our respiratory clinic from June 2009 to January 2010. Male:24 Female:26, Age:15-82. Fourty eight patients used the antibiotics. The heathy control group:Male14, Female13, Age19-75, there are not the respiratory tract infection in three month.1. Swab:The swabs are collected from acute and convalent period. The cotton pledget wipe orophryngeal then quake in 1ml physiological saline and press tube. The quantity of the epithelium is observed under the microscope and store in-80 degree.2. sputum:The sputum from the first or second day when patients are in the hospital. And to be observed if it is up to standard and stored -80 degree.3. The control group only have respiratory secretion by coughing.(二) polymerase chain reaction:The swab is treated according to the MP kit. The sputum and the secretion of the control group are first digested by 4% sodium hydroxide and then treated according to the procedure of operating of the swab.The acute swab sample is 49, the positive rate:73.5% The convalent swab sample is 22, positive rate 54.5%. After the paired sample t test testing p=0.044.The 24 sputums detected by FQ-PCR. positive rate 100%. After the paired sample t test testing p=0.051.三,The positive rate of the control group is 26.9%. The MP infection is definedif the DNA of MP is equal or greater than 107copies/ml. So there are 51percentates CAP patients who was infected by Mycoplasma pneumoniae.一,The positive rate is hgher in the acute swab sample than the convalent one.二,There is a higher sensitivity in the sputum sample than in the swab.