Article

Sample type is crucial to the diagnosis of Mycoplasma pneumoniae pneumonia by PCR.

Laboratory of Respiratory Viruses and Mycoplasmas, Department of Microbiology, National Public Health Institute, Mannerheimintie 166, FIN-00300 Helsinki, Finland.
Journal of Medical Microbiology (impact factor: 2.5). 04/2005; 54(Pt 3):287-91. pp.287-91
Source: PubMed

ABSTRACT Sensitive and specific methods for rapid laboratory diagnosis of Mycoplasma pneumoniae were not available until nucleic acid amplification methods were developed. The choice of sample type and method of sampling are crucial to optimal diagnostic efficacy. Three types of respiratory samples from 32 young military conscripts with pneumonia were collected during an outbreak of M. pneumoniae infection. Sputum, nasopharyngeal aspirate and throat swab specimens were tested by 16S rRNA gene-based PCR with liquid-phase probe hybridization, and the results were compared with serology. The PCR result was positive for 22 (69 %) of the sputa, 16 (50 %) of the aspirates and 12 (37.5 %) of the swabs. Serology with increasing or high titres supported the positive findings in all instances. Sputum, when available, is clearly the best sample type for young adults with pneumonia.

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    Anna C Nilsson, Per Björkman, Kenneth Persson
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Keywords

16S rRNA gene-based PCR
 
32 young military conscripts
 
liquid-phase probe hybridization
 
nasopharyngeal aspirate
 
nucleic acid amplification methods
 
PCR result
 
positive findings
 
rapid laboratory diagnosis
 
respiratory samples
 
sample type
 
sampling
 
specific methods
 
sputa
 
Sputum
 
swabs
 
titres
 
young adults
 

Riitta Räty