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OBJECTIVE: Trichotillomania/hair pulling disorder (HPD) and excoriation/skin picking disorder (SPD) are childhood-onset, body-focused repetitive behaviors that are thought to share genetic susceptibility and underlying pathophysiology with obsessive-compulsive disorder (OCD) and Tourette syndrome (TS). We sought to determine the prevalence of DSM-5 HPD and SPD in TS patients, and to identify clinical factors most associated with their co-morbidity with TS. METHOD: Participants included 811 TS patients recruited from TS specialty clinics for a multi-center genetic study. Patients were assessed using standardized, validated semi-structured interviews. HPD and SPD diagnoses were determined using a validated self-report questionnaire. HPD/SPD prevalence rates were calculated, and clinical predictors were evaluated using regression modeling. RESULTS: 3.8% and 13.0% of TS patients met DSM-5 criteria for HPD and SPD, respectively. In univariable analyses, female sex, OCD, and both tic and obsessive-compulsive severity were among those associated with HPD and/or SPD. In multivariable analyses, only lifetime worst-ever motor tic severity remained significantly associated with HPD. Female sex, co-occurring OCD, ADHD and motor tic severity remained independently associated with SPD. CONCLUSION: This is the first study to examine HPD and SPD prevalence in a TS sample using semi-structured diagnostic instruments. The prevalence of HPD and SPD in TS patients, and their association with increased tic severity and co-occurring OCD, suggests that clinicians should screen children with TS and related disorders for HPD/SPD, particularly in females and in those with co-occurring OCD. This study also helps set a foundation for subsequent research regarding HPD/SPD risk factors, pathophysiology, and treatment models.

A 16-year-old left-handed boy with Tourette syndrome (TS) presented to the outpatient neurology clinic complaining of difficulty focusing and completing tasks resulting in impairment at home, school, and social gatherings. He developed recurrent sniffing and throat clearing at age 6, which waxed and waned over time, and had since experienced repeated movements of the head, face, hands, and legs and gulping vocalizations; a diagnosis of TS was established at age 7. His tics were preceded by a premonitory sensation and were partially suppressible. These symptoms led to discomfort, but not impairment. He struggled with planning and organizational skills since age 6, and at age 12 developed repeated washing and writing/rewriting rituals. Family history was notable for a maternal grandmother with attention-deficit/hyperactivity disorder (ADHD) and a father with repetitive eye-blinking and possible childhood obsessive-compulsive disorder (OCD). He had a normal birth followed by normal developmental milestones. Neurologic examination including smooth pursuit and voluntary saccadic eye movements was unremarkable.

Background: At autopsy, 20%–40% of chronic multiple sclerosis (MS) lesions are labeled “slowly expanding” and feature myelin phagocytosis at the lesion edge. As pathological lesion classification relies on a single, terminal time point, the rate of lesion expansion cannot be directly measured. Objective: To study long-term volume changes in individual MS lesions. Methods: Volumes of individual lesions on proton density magnetic resonance imaging (MRI) acquired between 1992 and 2015 were measured in 22 individuals (one lesion per person). After correction for acquisition protocol, a mixed model evaluated lesion volume changes. Results: The mean (standard deviation) lesion volume at baseline was 142 (82) mL, falling to 74 (51) mL after 16 (3) years. All lesions shrank over time. Change in lesion volume did not correlate with change in supratentorial brain volume ( p = 0.33). In simulations, the results could be explained by a process of slow radial expansion superimposed on substantially more rapid resorption of damaged tissue. Conclusion: We noted sustained radiological contraction of MS lesions, a surprising result given that fresh myelin breakdown products within chronic active lesions are observed relatively frequently at autopsy. Therefore, the primary pathological process in chronic lesions, even those described as “slowly expanding,” is likely to be tissue loss.