Direct molecular detection and genotyping of sensu lato in the cerebrospinal fluid of children with Lyme neuroborreliosis.

The current diagnostic marker of Lyme neuroborreliosis (LNB), the Borrelia burgdorferi sensu lato antibody index (AI) in the cerebrospinal fluid (CSF), has insufficient sensitivity in the early phase of LNB. We aimed to elucidate the diagnostic value of PCR for B. burgdorferi sensu lato in CSF from children with symptoms suggestive of LNB and to explore B. burgdorferi sensu lato genotypes associated with LNB in children. Children were prospectively included in predefined groups with a high or low likelihood of LNB based on diagnostic guidelines (LNB symptoms, CSF pleocytosis, and B. burgdorferi sensu lato antibodies) or the detection of other causative agents. CSF samples were analyzed by two B. burgdorferi sensu lato-specific real-time PCR assays and, if B. burgdorferi sensu lato DNA was detected, were further analyzed by five singleplex real-time PCR assays for genotype determination. For children diagnosed as LNB patients (58 confirmed and 18 probable) (n = 76) or nonLNB controls (n = 28), the sensitivity and specificity of PCR for B. burgdorferi sensu lato in CSF were 46% and 100%, respectively. B. burgdorferi sensu lato DNA was detected in 26/58 (45%) children with AI-positive LNB and in 7/12 (58%) children with AI-negative LNB and symptoms of short duration. Among 36 children with detectable B. burgdorferi sensu lato DNA, genotyping indicated Borrelia garinii (n = 27) and non-B. garinii (n = 1) genotypes, while 8 samples remained untyped. Children with LNB caused by B. garinii did not have a distinct clinical picture. The rate of detection of B. burgdorferi sensu lato DNA in the CSF of children with LNB was higher than that reported previously. PCR for B. burgdorferi sensu lato could be a useful supplemental diagnostic tool in unconfirmed LNB cases with symptoms of short duration. B. garinii was the predominant genotype in children with LNB.