18 Lyme disease as an emerging cause of Seventh Cranial Nerve Palsy (“Bell’s palsy”) in Nova Scotia

Abstract

Abstract Introduction/Background Lyme disease, a tick-borne zoonosis caused by the bacterium Borrelia burgdorferi, has emerged in Nova Scotia (NS) as a common illness. Since 2002 when Lyme disease was first diagnosed in NS, >1000 cases have been reported. Seventh cranial nerve palsy (CNP-7) is said to be the most common presentation of early disseminated Lyme disease in children in endemic areas. Objectives We aimed to determine the frequency of CNP-7 in NS and if physicians are considering Lyme disease as an etiology. Design/Methods A retrospective review of health records of children seen at the IWK Health Centre from 2000-2018 who were ≤18 years of age with an ICD-9 or 10 diagnosis of Bell’s palsy (CNP-7) was conducted. CNP-7 due to local infection, trauma, malignancy, or systemic neurologic disease was excluded. Results Of 237 ICD “Bell’s palsy” diagnoses, 66 cases were eligible, of which 60.6 % (n=40) were female. The median age was 10 years (range 0-16). Five cases of Lyme disease-associated CNP-7 were recognized (7.6%), all since 2013. No bilateral CNP-7 occurred; 59.1% of cases were on the left. Most children presented within 3 days of symptom onset (84.8%) to the emergency department (95.4%), and 56.1% subsequently saw a pediatric neurologist. The most common associated symptom with CNP-7 was headache (22.7%). Lyme disease was considered in the differential diagnosis in 34.8 % (n=23) of cases, and only since 2012. Systemic steroids were prescribed to 51.5 % (34/66) of children in the emergency department, for durations varying from 1 to 10 days. The most common steroid course length was 5 days. Antimicrobials were prescribed for 18 (27.3%) children including acyclovir, beta lactams and tetracyclines. Resolution of the facial palsy findings was documented in 45 children, of whom 36 (54.5%) had complete resolution and 9 (13.6%) had partial resolution. Four children with Lyme disease associated CNP-7 had complete resolution, and one had partial resolution. Conclusion There does not appear to be a standard approach to diagnosis and management of CNP-7 in this pediatric health centre. Lyme disease is not regularly considered in the differential diagnosis, which is surprising given the high incidence of Lyme disease in NS. These findings will be shared with health care providers most likely to see CNP-7 in order to develop a standard algorithm to the initial presentation of 7th cranial nerve palsy in children.