Nerve conduction study findings in children with cystic fibrosis

Abstract

Objective: The objective of this study is to evaluate nerve conduction studies in patients with cystic fibrosis (CF). Methods: Twenty-one patients, 7 (33.3%) boys and 11 (66.7%) girls were included with mean age of 10.04 ± 3.63 years. All of the patients were taking vitamin therapy and they were regularly on follow-up by allergists and gastroenterologists. Nerve conduction studies (NCS) were performed on the median and sural sensory nerves, peroneal, tibial, ulnar and median motor nerves. Results: Sixteen (76.2%) patients had abnormalities in NCV studies. Seven (33.3%) patients had demyelinating abnormality on median motor nerve studies and their vitamin A and vitamin D serum levels were significantly lower than the patients with normal motor nerve NCS (361.74 ± 8.77 vs 506.40 ± 156.74 p 0.012 and 9.64 ± 1.30 vs 19.94 ± 11.63 p 0.006). Four patients (19.4%) had abnormal finings on tibial motor nerve studies and they had significantly lower vitamin D levels than the patients with normal tibial NCS (9.47 ± 1.87 vs 18.16 ± 11.2 p 0.007). There were reduced vitamin A and D levels in patients with sural nerve conduction velocity (CV) abnormality (299.60 ± 17.81 vs 474.87 ± 149.30 p < 0.001 and 8.45 ± 0.77 vs 17.36 ± 10.85 p 0.002). In patients with abnormalities on sural nerve distal latancies (DL), ulnar nerve CV and tibial nerve amplitudes have significantly lower vitamin E, A and D levels. Vitamin D levels were higher in patients without any abnormalities on median motor nerve DL and CV, tibial nerve DL. Vitamin E levels found to be reduced in patients with prolonged DL. Conclusion: CF is associated with peripheral nerve dysfunction and there is a relationship between NCS abnormalities and vitamin A, E and D deficiencies. Potential peripheral neuropathy should be kept in mind and vitamin supplementation therapies should be evaluated carefully in CF patients.