Pallidal deep brain stimulation is an established treatment in dystonia. Available data on the effect in DYT-THAP1 dystonia (also known as DYT6 dystonia) are scarce and long-term follow-up studies are lacking. In this retrospective, multicenter follow-up case series of medical records of such patients, the clinical outcome of pallidal deep brain stimulation in DYT-THAP1 dystonia, was evaluated. The Burke Fahn Marsden Dystonia Rating Scale served as an outcome measure. Nine females and 5 males were enrolled, with a median follow-up of 4 years and 10 months after implant. All benefited from surgery: dystonia severity was reduced by a median of 58% (IQR 31-62, p = 0.001) at last follow-up, as assessed by the Burke Fahn Marsden movement subscale. In the majority of individuals, there was no improvement of speech or swallowing, and overall, the effect was greater in the trunk and limbs as compared to the cranio-cervical and orolaryngeal regions. No correlation was found between disease duration before surgery, age at surgery, or preoperative disease burden and the outcome of deep brain stimulation. Device- and therapy-related side-effects were few. Accordingly, pallidal deep brain stimulation should be considered in clinically impairing and pharmaco-resistant DYT-THAP1 dystonia. The method is safe and effective, both short- and long-term.

Ataxia telangiectasia (A-T), caused by biallelic variants in the ATM gene, is a multisystemic and severe syndrome characterized by progressive ataxia, telangiectasia, hyperkinesia, immunodeficiency, increased risk of malignancy, and typically death before the age of 30. In this retrospective study we describe the phenotype of 14 pediatric and adult A-T patients evaluated at the Karolinska University Hospital in Sweden during the last 12 years. Most of the patients in this cohort were severely affected by ataxia and wheelchair use started at a median age of 9 years. One patient died before the age of 30 years, but five patients had survived beyond this age. Four patients received prophylactic immunoglobulin replacement therapy due to hypogammaglobulinemia and respiratory complications ranged from mild to moderate severity. Three patients developed type 2 diabetes in young adulthood and nine patients (64%) had a history of elevated liver function tests. Four patients were diagnosed with cancer at ages 7, 41, 47, and 49 years. All the ATM variants in these patients were previously reported as pathogenic except one, c.6040G > A, which results in a p.Glu2014Lys missense variant. With increased life expectancy, A-T complications such as diabetes type 2 and liver disease may become more common. Despite having severe neurological presentations, the A-T patients in this case series had relatively mild infectious and respiratory complications.

Background: The Dyskinesia Impairment Scale (DIS) is a new assessment scale for dystonia and choreoathetosis in children and youth with dyskinetic cerebral palsy. Today, the Burke–Fahn–Marsden Dystonia Rating Scale (BFM) is mostly used to assess dystonia in children with inherited dystonia. The aim of this study was to assess reliability and validity of the DIS in children and youth with inherited or idiopathic dystonia. Methods: Reliability was measured by (1) the intraclass correlation coefficients (ICCs) for inter-rater and test-retest reliability, as well as (2) standard error of measurement (SEM) and minimal detectable difference (MDD). For concurrent validity of the DIS-dystonia subscale, the BFM was administered. Results: In total, 11 males and 9 females (median age 16 years and 7 months, range 6 to 24 years) were included. For inter-rater reliability, the ICCs for the DIS total score and the dystonia and choreoathetosis subscale scores were 0.83, 0.87, and 0.71, respectively. For test-retest reliability, the ICCs for the DIS total score and the dystonia and choreoathetosis subscale scores were 0.95, 0.88, and 0.93, respectively. The SEM and MDD for the total DIS were 3.98% and 11.04%, respectively. The Spearman correlation coefficient between the dystonia subscale and the BFM was 0.88 (p < 0.01). Conclusions: Good to excellent inter-rater, test-retest reliability, and validity were found for the total DIS and the dystonia subscale. The choreoathetosis subscale showed moderate inter-rater reliability and excellent test-retest reliability. The DIS may be a promising tool to assess dystonia and choreoathetosis in children and young adults with inherited or idiopathic dystonia.