Relapses in Patients Treated with High-Dose Biotin for Progressive Multiple Sclerosis.

High-dose biotin (HDB) is a therapy used in non-active progressive multiple sclerosis (PMS). Several reports have suggested that HDB treatment may be associated with an increased risk of relapse. We aimed to determine whether HDB increases the risk of clinical relapse in PMS and describe the characteristics of the patients who experience it. We conducted a French, multicenter, retrospective study, comparing a group of PMS patients treated with HDB to a matched control group. Poisson regression was applied to model the specific statistical distribution of the annualized relapse rate (ARR). A propensity score (PS), based on the inverse probability of treatment weighting (IPTW), was used to adjust for indication bias and included the following variables: gender, primary PMS or not, age, EDSS, time since the last relapse, and co-prescription of a DMT. Two thousand six hundred twenty-eight patients treated with HDB and 654 controls were analyzed with a follow-up of 17 ± 8 months. Among them, 148 validated relapses were observed in the group treated with biotin and 38 in the control group (p = 0.62). After adjustment based on the PS, the ARR was 0.044 ± 0.23 for the biotin-treated group and 0.028 ± 0.16 for the control group (p = 0.18). The more relapses there were before biotin, the higher the risk of relapse during treatment, independently from the use of HDB. While the number of relapses reported for patients with no previous inflammatory activity receiving biotin has gradually increased, the present retrospective study is adequately powered to exclude an elevated risk of relapse for patients with PMS treated with HDB.

Whole-body reversible neuropathic pain associated with right parieto-temporal operculum single inflammatory lesion in a patient with multiple sclerosis: A case report.

BACKGROUND: The posterior insula and the medial parietal operculum (PIMO) are part of the pain network. Pain can be induced by direct stimulation of the PIMO, but the clinical consequence of lesions in this brain area is not well known. CASE REPORT: We report the case of a patient with multiple sclerosis who presented a relapse characterized by isolated widespread neuropathic pain. The MRI displayed a single new inflammatory lesion in the juxta cortical white matter of the opercular region. This lesion was extended to the parietal operculum and was associated with the pain syndrome. The patient was treated with high-dose intravenous methylprednisolone, and the pain disappeared progressively. Diffusion-tensor MRI showed that some of the fibres passing through the lesion ended in the PIMO. CONCLUSION: Based on diffusion-tensor MRI we hypothesize that the partial disconnection from afference to the PIMO can lead to widespread neuropathic pain. SIGNIFICANCE: Most of the data concerning the functional role of the PIMO come from stereoelectroencephalography in presurgical evaluation of epilepsy, or from functional imaging (PET or fMRI). There is, however, very few data on the consequences of the lesion of the PIMO. Here, we report the first case of a transient widespread pain syndrome associated to a single, small and reversible inflammatory lesion of the PIMO. Thus, this case highlights the key role of the PIMO in spatial perception of pain.