DETECTION OF MYCOPLASMA-PNEUMONIAE BY POLYMERASE CHAIN-REACTION IN LUNG ASPIRATES FROM PATIENTS WITH COMMUNITY-ACQUIRED PNEUMONIA

Study objective: This study was designed to evaluate the usefulness of polymerase chain reaction (PCR) to detect Mycoplasma pneumoniae DNA i n samples obtained by transthoracic needle aspiration (TNA). Design: P rospective study of cases. Setting: A university hospital in Lleida, S pain. Patients: A total 101 unselected patients, admitted between Janu ary 1993 and March 1994 in the emergency department, with a clinical a nd radiologic picture of community-acquired pneumonia, and without con traindications for TNA application. Interventions: Patients were studi ed with conventional diagnostic techniques for community-acquired pneu monia. In addition, a sample obtained by TNA was processed by the foll owing methods: culture in standard media, culture in selective media f or Legionella, detection of capsular antigens for Streptococcus pneumo niae and Haemophilus influenzae, and detection of M pneumoniae specifi c genome by PCR. Results: Serologic data were not available in eight p atients and were excluded from this analysis. M pneumoniae PCR amplifi cation was possible in eight cases, well correlated with serologic res ponses indicating current infection. Samples from ten additional patie nts, negative by PCR, were found to be demonstrative of recent M pneum oniae infection by serologic study. Finally, in all remaining 75 cases , including the 59 patients for whom a different microbial diagnosis w as established, M pneumoniae PCR test gave negative results. Conclusio n: This study indicates that PCR, applied to samples obtained by TNA, appears to be a moderately sensitive and highly specific method for ra pid detection of M pneumoniae lung infection.