Diagnostic revisions in multiple sclerosis

Abstract

Objectives: The diagnostic criteria for inflammatory demyelinating diseases of the central nervous system have evolved over the past years. Close follow up and accurate multiple sclerosis (MS) diagnosis are key to optimal treatment. We retrospectively reviewed the patients who had a diagnostic revision. Methods: The medical records of patients referred to our MS clinic (Centro Hospitalar Universitário de São João, Porto, Portugal) (n = 635) between 2009 and 2016 were reviewed. A total of 62 patients were identified, 44 were misdiagnosed with MS; 18 had another diagnosis, later redefined as MS. A total of 44 controls (with MS diagnosis) were matched to the 44 misdiagnosed cases, and a statistical analysis was carried out to determine the predictors of misdiagnosis. Results: The mean age of our population (n = 44) was 51 ± 11 years; 77% were women. The mean duration of misdiagnosis was 13 years. Optic neuritis was the most frequent presenting symptom (25%), followed by spinal cord syndrome and non‐specific neurological symptoms (20% each). The most frequent MS misdiagnoses were non‐specific white matter hyperintensities, optic neuritis and cerebrovascular disease. The mean Extended Disability Status Scale and Multiple Sclerosis Severity Score was 0 (SD 2) and 0.6 (SD 2), respectively, in the misdiagnosed group, and 3.5 (SD 5.4) and 3.2 (SD 5.6), respectively, in the control group. From all the variables analyzed, we found that the presence of black holes and spinal cord lesions were predictors of a correct MS diagnosis (P < 0,05). Conclusions: Our series underlines the need to continuously rethink an MS diagnosis and to thoughtfully use paraclinical tests (oligoclonal bands and magnetic resonance imaging) avoiding an unfounded diagnosis. The first event might not be atypical, as has been reported in other series.