Adult-Onset Dystonic Tics Responsive to Aripiprazole

Sir, Tics are sudden, brief, intermittent, involuntary, or semi-voluntary movements (motor tics) or sounds (phonic or vocal tics).[1-3] A distinguishing feature from other hyperkinetic disorders of the group is that they can often be suppressed for some time and exhibit subsequent release of mounting tension with their reappearance.[1] Tics are primarily classified to be a childhood disorder, the most common being the Tourette syndrome.[2] When the first appearance is seen in adulthood, it is labeled as “unspecified tic disorder.” Whether the adult-onset tics are reminiscent of the childhood tic disorder or cluster a new entity largely remains unclarified. Only a few case series can be found in literature describing adult-onset tics.[3-5] Motor tics, initially classified by Jankovic, on their phenomenology into the following three types: (1) Clonic, when tics involve only a single muscle or a group of muscles, causing a brief, jerking movement; (2) Tonic, when tics reflect an isometric contraction, typically manifesting with a brief tension of abdominal or limb muscles (3) Dystonic, when tics are slower, causing a briefly sustained abnormal posture.[1] Misdiagnosis with other hyperkinetic disorders like chorea, myoclonus, or psychiatric is not an uncommon occurrence.[6,7] Insights into the physiology of tic disorders point to a defect in the dopaminergic pathway. This fact is further strengthened by the use of dopamine antagonist drugs such as haloperidol, risperidone, and other antipsychotics for the management of tic disorders.[8] Owing to the wide phenotypic variability, there is no uniform treatment strategy. Adult-onset primary tic is a rare occurrence. We describe a case of adult-onset primary dystonic tics, which was very well responsive to aripiprazole. Aripiprazole is being used in the pediatric population with a good response. Aripiprazole has been considered to be effective in tics with fewer side effects.[9-12] A 69-year-old male, with no comorbidities presented to the movement disorder clinic with abnormal twitchy movements of eyes and perioral region for the last 1 year. The patient also had tremors of both upper limbs which was, symmetrical, insidious onset slowly progressive most marked while holding a posture, was not associated with any slowness, stiffness, or change in gait or speech. The patient, however, did not consult a clinician as the tremor was not disabling. Almost, 7 years back, he underwent ocular surgery for cataracts in both the eyes, following which he noted abnormal twitching movements of both the eyes in the form of involuntary transient movements in either direction, closure of both eyelids. There was a worsening of these movements on sun exposure but denies any diurnal variation or improvement with rest. Almost 3–4 months into the illness the patient then noticed similar twitchy movements of the lips, mouth, and tongue, shrugging of the left shoulder and abdomen. Almost simultaneously he reported having poor sleep quality. He denied a history of any similar illness in the family or any drug intake. There was no history of compulsive vocalization or grunting sounds. These movements, however, disappeared in sleep. On direct questioning, he was able to hold these movements, with mounting tension which was released after the movement was performed. He was not receiving any treatment currently, but in the past, he had been injected with botulinum toxin at a different institute and the response was not good. Briefly, he also received trihexyphenidyl and clonazepam, but the response was not good. On clinical examination, a general physical examination was normal. Simple motor dystonic tics involving the eyes, perioral region, tongue, left shoulder, and abdomen were seen [See video segment 1]. The Yale Global Tic Severity Scale (YGTSS) score was 58 at the initial presentation. Postural tremor of both upper limbs was also noted. A detailed neurological examination did not reveal any other findings. {"href":"Single Video Player","role":"media-player-id","content-type":"play-in-place","position":"float","orientation":"portrait","label":"Video 1.","caption":"","object-id":[{"pub-id-type":"doi","id":""},{"pub-id-type":"other","content-type":"media-stream-id","id":"1_kme00zv8"},{"pub-id-type":"other","content-type":"media-source","id":"Kaltura"}]} Routine blood and urine tests were normal. His magnetic resonance imaging of the brain was also normal. Since the response to trihexyphenidyl, clonazepam, and botulinum toxin was not good, he was prescribed tablets of aripiprazole (5 mg once daily) to which he showed very good improvement and his abnormal movements decreased significantly at the end of 3-weeks follow-up [See video segment 2]. His YGTSS score dropped to 31. The patient remains in follow-up at the regular interval. He is still doing good at 9 months from initial treatment. {"href":"Single Video Player","role":"media-player-id","content-type":"play-in-place","position":"float","orientation":"portrait","label":"Video 2.","caption":"","object-id":[{"pub-id-type":"doi","id":""},{"pub-id-type":"other","content-type":"media-stream-id","id":"1_qmzuihy9"},{"pub-id-type":"other","content-type":"media-source","id":"Kaltura"}]} To our knowledge, only a few cases of adult-onset primary tic disorder have been reported so far in the medical literature [Table 1].[3-5,7,13-17] The prevalence of tic disorder in adults was reported to be 0.4% by Wenning et al.[18] Despite the controversy, that most of the adult-onset tics are a resurgence of the childhood tics, there remains in literature these well-described arrays of patients who had tics as adult-onset without any history.[19] Of them, most had some underlying secondary cause. Furthermore, of all the described cases the description of dystonic tics is very rare.[4,5] A clear cut male preponderance has been described.[19] Chouinard et al. found that symptomatic or secondary tic disorders inevitably presented as a new-onset disorder in adults, rather than as recurrent childhood tics.[4]Table 1: Reported cases, adult-onset primary dystonic ticsIt is of utmost importance that these patients are differentiated from the potential tic mimickers. Myoclonus, chorea, dystonia, and stereotypy are the commoner differentials meriting exclusion in cases of adult-onset tics and may pose a clinical challenge.[6] A comprehensive list of predisposing conditions needs appraisal e.g., infections, drugs, neurodegenerative illness, and stroke.[20] Trauma is another important predisposing condition identified.[21] Besides, the underlying psychiatric condition warrants necessary attention as elucidated by a case from Versace et al.[22] Several associated movement disorders were found in patients with tics. Mejia et al. reported associated movement disorders in around 46% of patients and tremors were seen in 17% of this cohort.[6] There was an associated postural tremor in our patient. Obsessive-compulsive behavior was the most common comorbidity in this group. Chouinard and Ford found, in their study, poor response to oral medications.[4] However, ensuing with reports to suggest the role of aripiprazole in both “Tourette syndrome” and adult-onset tics, we chose aripiprazole since the patient was not previously medicated for tics. In his subsequent visit after 3 weeks, he showed around 60% improvement in his symptoms. The response to treatment is often variable and lacks consensus guidelines due to the paucity of cases. Our case highlights several rarities, the age of onset of tics was considerably on the latter end and it being dystonic in phenomenology, and an absence of concomitant psychiatric disorders or absence of any obvious trigger further makes the case interesting.[4-6] This case also highlights the potential role aripiprazole can play in the treatment of adult-onset tics as in children.[9-12] Declaration of patient consent The authors certify that they have obtained appropriate consent from the patient. The patient consented for his video recording and understood that his name would not be mentioned in the case. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.