PROSPECTIVE-STUDY TO DETERMINE CLINICAL RELEVANCE OF DETECTION OF PNEUMOCOCCAL DNA IN SERA OF CHILDREN BY PCR

We undertook a prospective study to evaluate the accuracy of PCR of se rum (aimed at the pneumococcal pneumolysin gene) at detecting pneumoco ccal infections in infants and children, The assay was positive for al l blood and cerebrospinal fluid culture-positive samples and for 38 an d 44% of patients,vith lobar pneumonia and acute otitis media, respect ively. It was positive for 17% of healthy controls. There was a marked effect of age on the rate of positivity among healthy controls, with the highest rate (33%) being in 2-year-old children, the age group wit h the highest rate of nasopharyngeal (NP) carriage; the lowest rate wa s found among infants <2 months of age (13%) and adults ages 18 to 50 years (0%), age groups with the lowest NP pneumococcal carriage rates, Carriers of pneumococci in the nasopharynges had a higher rate of pos itivity than noncarriers of pneumococci in the nasopharynges for all g roups, Our results suggest that although PCR of serum is a sensitive t est for the detection of Streptococcus pneumoniae in sterile fluids, i ts high rate of positivity for healthy controls, related to NP pneumoc occal carriage, might exclude it from being useful in detecting deep-s eated pneumococcal infections.