PP05.2 – 2269: Decreased levels of nasal nitric oxide in children with midline neuroanatomical anomalies: A possible connection between ciliary dysfunction and isolated nervous system defects?

Objectives Given the involvement of cilia in neurodevelopment, we set to determine whether children with midline neuroanatomical defects have increased prevalence of ciliary dysfunction, using nasal nitric oxide measurement, a screening test for Primary Ciliary Dyskinesia. Methods We measured the nasal nitric oxide levels of 26 children ages 6–17, with congenital midline central nervous system defects, who are otherwise healthy. We evaluated the effect of variables including: age, gender, and anomaly (brain, spinal cord, or combined) on our measurements. We compared our results to the previously established normal range (153.6–509.9 nL/min), and to the cutoff for children with Primary Ciliary Dyskinesia (77 nL/min). Results The overall range for nasal nitric oxide in our cohort was 56.5 to 334.7 nL/min, with age, gender, and anomaly not having a significant effect. The overall mean, 217.7 nL/min, was significantly lower than the preestablished mean in normal children, 314.51 nL/min (p<0.01). Four subjects (15.4%) had nitric oxide levels below the lower end of normal, with two (7.7%) having values below the cutoff for Primary Ciliary Dyskinesia. Conclusions This is the first study reporting a possible association between ciliary dysfunction and isolated congenital midline neuroanatomical defects, not in the context of any known syndrome. We suggest that genes known to cause isolated CNS defects, may also be implied in the function of cilia. Longitudinal studies are required to investigate whether, in children with abnormal measurements, nasal nitric oxide levels normalize over time, and whether these children suffer from any respiratory sequelae. [ABSTRACT FROM AUTHOR]