PEDIATRIC NERVE BIOPSY IN TERTIARY REFERRAL FREQUENTLY ASSISTS IN DIAGNOSIS AND THERAPEUTIC MANAGEMENT

OBJECTIVE: To evaluate the usefulness of peripheral nerve biopsies in children refereed to a tertiary care center BACKGROUND: Childhood peripheral nerve diseases are both unique and similar to their adult counterparts. Comprehensive evaluation of the utility of nerve biopsies in affected children has not been reported. DESIGN/METHODS: Utilizing an electronic-medical-record retrieval system we identified 316 pediatric (≤18 yo) nerve biopsies from children where clinical information was available. RESULTS: : Median age at biopsy was 9.8 yrs (4days-18yrs). Median follow up was 6 months (0-480 months). Ten children died in the study period related to their neurological illnesses. Cutaneous sensory nerves were most commonly biopsied, but 18 underwent targeted fascicular proximal biopsies. Pre-biopsy diagnoses were diverse including; polyneuropathy n=150, CNS disease and polyneuropathy n=34; hypotonia n=15; polyradiculoneuropathy n=18; plexopathy n=15; sciatic neuropathy n=13; mononeuropathy n=22, among others. A distinct histopathologic diagnosis was possible in 113 (36[percnt]) most commonly: inflammatory/autoimmune, including CIDP n=29; neoplasm n=22; hypertrophic inherited neuropathy n=19; vasculitis n=14; giant axonal neuropathy n=5, among others. Nerve biopsy confirmed the suspected clinical diagnosis in 91 cases (29[percnt]), changed or refined the initial clinical diagnosis in 182 cases (58[percnt]) and was non-contributory in 43 cases (13[percnt]). Only 3 children reported difficulty with postoperative pain at the biopsy site beyond 1 month. Patient treatment was modified in 80 cases (25[percnt]) as a direct result of the biopsy. Of these 80 cases, 59 (19[percnt] of the entire cohort) were documented to have a direct clinical improvement related to a change in treatment most commonly by immunotherapy, but also by radiation, surgery for excision of tumor, chemotherapy and direct medical council. Certain pre-biopsy diagnosis provided low yield including, hypotonic infant. CONCLUSIONS: Tertiary nerve biopsy referral among select children has a high diagnostic yield frequently altering treatment with clinical improvements. Study Supported by: NINDS K08NS065007 (C.J.K.) Disclosure: Dr. Ida has nothing to disclose. Dr. Dyck has nothing to disclose. Dr. Selcen has nothing to disclose. Dr. Bodensteiner has received personal compensation in an editorial capacity for Pediatric Neurology. Dr. Mauermann has nothing to disclose. Dr. Dyck has nothing to disclose. Dr. Klein has nothing to disclose.