Résumé
The multiplicity of indications and operators performing botulinum toxin injections means that injections are required at intervals of < 3 months. The two main risks of short-interval toxin injections are Secondary Treatment Failure (STF) and systemic dissemination. Method: monocentric retrospective study (Nîmes University Hospital). Analysis of records via a PMSI database of patients injected from 2020 to 2022. Selection of patients with at least one interval < 3 months. Analysis of all toxin injection characteristics (site, type of toxin, dose, etc.) and patients (age, gender, pathology, etc.). The aim of this study was to assess whether shortinterval injections would be a risk factor for systemic dissemination or STF. Results: of the 59 pairs of injections selected with an interval of < 6 weeks, there were no clinical signs of systemic dissemination. Concerning STF, of the 159 patients with an interval of < 3 months, 12 PES were noted. The only statistically significant difference between PES+ and PESpatients was the number of short intervals (median 2 vs. 6 with a p-value equal to 0.003). Discussion: no link was found between short intervals and systemic dissemination. The link with STF due to toxin alloimmunization is debated in the literature, owing to a large number of differential diagnoses and a low rate of true alloimmunization.