X-linked Charcot-Marie-Tooth Disease Presenting with Stuttering Stroke-like Symptoms.

X-linked Charcot-Marie-Tooth disease (CMTX1) is the second most common form of Charcot-Marie-Tooth disease (CMT). It is caused by a mutation in the gap junction ß 1 (GJB1) gene, which encodes for connexin-32. In addition to the peripheral neuropathy and foot deformities observed in classic CMT, central nervous system symptoms and magnetic resonance imaging (MRI) signal abnormalities in the brain have been reported in patients with CMTX1. Here we describe two cases of adolescent males who presented with stuttering neurologic deficits that were initially suggestive of acute ischemic stroke and were ultimately diagnosed with genetically confirmed CMTX1. Both patients had evidence of T2 hyperintensity and decreased diffusion on MRI in the centrum semiovale, posterior corona radiata, posterior periventricular white matter, and corpus callosum. Though rare, these cases illustrate the importance of comprehensive neurologic history, physical examination, and appropriate diagnostic evaluation.

Validation of claims-based diagnoses of adult and pediatric neuromyelitis optica spectrum disorder and variations in diagnostic evaluation and treatment initiation.

BACKGROUND: Neuromyelitis optica spectrum disorder (NMOSD) is a rare demyelinating disease in need of more studies to determine effective treatment regimens. The rarity of the disorder, however, makes large randomized-controlled trials challenging. Validation of the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) code for NMO could facilitate the use of large healthcare claims data for future research. We aimed 1) to determine the positive predictive value (PPV) of the ICD-9-CM code for NMO as well as evaluate case-finding algorithms for the identification of patients with NMO/NMOSD and 2) to compare the evaluation of and treatment for pediatric versus adult patients. METHODS: This was a multicenter retrospective cohort study of patients with ≥ 1 ICD-9 code for NMO seen at 3 pediatric and 2 adult United States medical centers from 2001-2016. Using a standardized data entry form, pediatric and adult neurologists and rheumatologists reviewed patients' medical records to determine whether patients fulfilled the 2006 criteria for NMO and/or the 2015 criteria for NMOSD in order to determine the positive predictive value (PPV) for the ICD-9-CM code. Demographic and clinical information was abstracted from patient medical records to ascertain variables then evaluated in case-based finding algorithms for further identification of patients with true NMO/NMOSD. We also evaluated differences in clinical characteristics between pediatric and adult patients using chi-squared or Fisher's exact tests, as appropriate, to assess for treatment variation. RESULTS: A single code for NMO had a PPV of 47% across all sites, with significant site variation (0-77%). The best case-finding algorithm included at least 5 codes as well as a documented hospitalization (PPV = =90% for children and PPV = 92% for adults). Children were more likely to be evaluated by a rheumatologist or ophthalmologist, undergo magnetic resonance imaging of the orbits, and receive immunosuppressive and biologic agents than their adult counterparts. Rituximab was administered similarly among the two groups. CONCLUSION: The ICD-9 code for neuromyelitis optica (NMO) is inaccurate for identification of NMO/NMOSD. Using case-finding algorithms increases the PPV. The initial diagnostic evaluation and treatment of NMOSD differs significantly between children and adults.