Polymerase chain reaction for detection ofChlamydia pneumoniae in gargled-water specimens of children

Abstract

The objective of the present study was to establish the occurrence of Chlamydia pneumoniae by direct detection in gargled-water specimens obtained from 193 children suffering from acute or chronic respiratory infections. Specimens were analyzed by an indirect immunofluorescence test (IIF), a genus-specific antigen enzyme immunosorbent assay (EIA) and the polymerase chain reaction (PCR). The pathogen was detected in three children by PCR only. As underlying disease, chronic obstructive bronchitis resistant to therapy was reported. In two of the children, the presence of pneumonia could be verified by X-ray. With a detection threshold of target DNA obtained from two inclusion forming units (IFU), the PCR proved clearly more sensitive than EIA becoming positive at levels of 100 IFU and above. No interpretable results could be obtained for the IIF.

Molecular Diagnosis of Chlamydia pneumoniae Infection

“…The specimen collection depends on the type of clinical condition. Suitable specimens for use in the detection of C. pneumoniae include sputum specimens (10,85), bronchoalveolar lavage (BAL) specimens (17,22), swabs of the nasopharynx and throat (6,10,20,25,29), nasopharyngeal (42,86) and ear fluid (9, 82) aspirates, gargled water (71), and tissues from a biopsy or autopsy (45,68). A few studies on the detection of C. pneumoniae DNA in blood specimens have been published (11,61,62), but the use of blood samples for direct detection of C. pneumoniae needs further evaluation.…”

Relevance of nucleic acid amplification techniques for the diagnosis of respiratory tract infections in the clinical laboratory

“…However, taking into account the shortcomings of serologic testing, in terms of specificity and sensitivity (58), it can be surmised that the techniques available fail to diagnose C. pneumoniae infections to an unknown extent, although the organism does not seem to be a common cause of respiratory infection in children (65). Therefore, several PCR primer sets have been developed to detect either outer membrane or 16S rRNA coding genes (10,19,55,58,66,143,157,160).…”

“…Some solutions have been proposed, including the use of samples such as gargled water, throat swabs, or nasopharyngeal swabs instead of nasopharyngeal aspirates or sputum (157,195), alternative sample treatment methods (62,117), and introduction of a nested PCR (11).…”

Asthma in Children

“…In 1995 Prückl et al [55] reported on 193 children aged 5 to 16 years with acute or chronic respiratory infections; 3 had chronic obstructive bronchitis which had proved resistant to antimicrobial therapy and the same 3 children had gargled water specimens positive for C. pneumoniae by PCR. Also in 1995, Emre et al [56] looked for evidence of C. pneumoniaespecific IgE by immunoblot in 45 children with and without culture-proven infection with C. pneumoniae and found that 86% of 14 culture-positive asthma patients also had C. pneumoniae-specific IgE compared to 9% of culture-positive pneumonia, 18% of culture-negative asthma and 22% of culture-negative asymptomatic patients.…”

“…After 2 courses of azithromycin, the child improved and became PCRnegative. [49,[52][53][54][55]57,61,62] However, because of the high background rates of infection in the nonasthmatic population, it is possible that some of the infections documented in patients with asthma occurred coincidentally and were not causal. [65] Case studies contain additional suggestive data supporting a role for atypical bacterial infection in acute wheezing and in the exacerbation, initiation and promotion of asthma in paediatric as well as in adult age.…”