The importance of clinical observation: A case of subtle tardive dyskinesia with paliperidone palmitate

To the Editor

Tardive dyskinesia (TD) is a chronic movement disorder characterised by persistent, uncontrolled, involuntary movements which can be attributed to antipsychotic medication use. TD is seen more commonly in older patients with prolonged antipsychotic exposure. However, atypical cases can occur, necessitating early detection and management.

We present a case of a 23-year-old man with schizoaffective disorder. He presented with a 2-month history of mood and psychotic symptoms and underwent a 6-week period of admission where he was prescribed olanzapine 20 mg. Following discharge, his olanzapine dose was reduced and he was started on oral risperidone 2 mg with a view to switching to paliperidone palmitate (PP) depot and stopping olanzapine due to patient choice. He was given two loading doses of PP 150 mg and 100 mg respectively, and then maintained on 100 mg monthly. Initial side-effects of sedation and increased anxiety were noted, however his mood and psychotic symptoms settled.

In a subsequent review 9 months later, we noted the presence of subtle, writhing lingual movements in the absence of other extrapyramidal symptoms. The patient’s mother stated these were present for weeks, despite the patient and his nurse being unaware. There was no personal history or family history of neurological disorders. TD was therefore suspected and PP was immediately stopped. Three months later, his lingual movements subsided. Although no grading scales were used to assess his movements, it was unlikely that self-assessment rating scales such as the Liverpool University Neuroleptic Side Effect Rating Scale (LUNSERS) (Day et al., 1995) would have identified his movements as the patient was unaware of them. The abnormal involuntary movement scale (AIMS) (Early et al., 2013) may have identified them; however, the use of such scales in routine practice is rare.

Patients are generally screened for metabolic side effects prior to initiating antipsychotics and during routine reviews. Screening includes blood tests, physical examinations and an electrocardiogram. However, the review of any movement disorders is largely neglected. The AIMS is a simple rating scale for detecting and monitoring abnormal movements over time, which may later progress to TD. Though the assessment takes time to perform and puts pressure on busy clinics, the potential benefit of preventing a debilitating, chronic condition largely outweighs this.

This case highlights the difficulties of detecting subtle movements which may manifest as TD. Psychiatrists must be aware that TD can occur with atypical agents, in young first-episode patients, and must screen for such symptoms routinely during clinical reviews.