Drug-Induced Movement Disorders.

Drug-induced movement disorders (DIMDs) are most commonly associated with typical and atypical antipsychotics. However, other drugs such as antidepressants, antihistamines, antiepileptics, antiarrhythmics, and gastrointestinal drugs can also cause abnormal involuntary movements. Different types of movement disorders can also occur because of adverse drug reactions. Therefore, the important key to diagnosing DIMDs is a causal relationship between potential offending drugs and the occurrence of abnormal movements. The pathophysiology of DIMDs is not clearly understood; however, many cases of DIMDs are thought to exert adverse mechanisms of action in the basal ganglia. The treatment of some DIMDs is quite challenging, and removing the offending drugs may not be possible in some conditions such as withdrawing antipsychotics in the patient with partially or uncontrollable neuropsychiatric conditions. Future research is needed to understand the mechanism of DIMDs and the development of drugs with better side-effect profiles. This article reviews the phenomenology, diagnostic criteria, pathophysiology, and management of DIMDs.

Movement Disorders and Musculoskeletal System: A Reciprocal Relationship.

The association of movement disorders (MDs) with musculoskeletal (MSK) disorders is observed in two principal scenarios. First, MDs patients may present with MSK issues. This phenomenon is primarily observed in parkinsonian syndromes, but may also be seen in patients with dystonia, Tourette syndrome, and some gene-related MDs. Second, there are MSK disorders that may produce or mimic MDs. Important primary MSK disorders producing MDs are joint hyperlaxity syndrome, non-traumatic craniovertebral junction anomalies, congenital muscular torticollis, and rheumatoid arthritis. Peripheral trauma to the MSK system may also lead to MDs commonly referred to as peripherally induced MDs. The exact pathogenesis of these disorders is not clear, however many patients have associated sensory phenomena such as complex regional pain syndrome. Herein, we provide an overview of disorders that may manifest with a combination of MSK and MDs, as detailed above. The most common MDs are discussed in each section, along with important clinical points, suggested diagnostic workups, and possible differential diagnoses.

Autoimmune Movement Disorders: A Video-Based Case Series of 11 Patients.

Autoimmune encephalitis (AIE) constitutes an important treatable cause of movement disorders. We aimed to highlight the spectrum of movement disorder and other salient features of AIE patients diagnosed at our tertiary care centre and describe their clinical symptoms, diagnostic approach, treatment, and outcome. We evaluated 11 patients who presented with movement disorder in association with AIE at our centre. Various abnormal movements observed were tremor, dyskinesias, stereotypy, dystonia, ataxia, asterixis, myoclonus, and parkinsonism. Antibodies were detected against NMDAR (n = 3), LGI-1 (n = 2), GAD-65 (n = 1), CASPR-2 (n = 1), Sox-1 (n = 1), Yo (n = 1), and thyroid peroxidase (n = 1). One patient was diagnosed with opsoclonus myoclonus syndrome associated with the suspected neuroblastic tumour. Six patients responded well to first-line immunotherapy (intravenous immunoglobulins or steroid or both). Three patients with anti-NMDAR antibodies received second-line therapy consisting of rituximab. Movement disorder is one of the most consistent features of AIE. Understanding of the ever-expanding spectrum of antibodies associated with movement disorders helps in the early diagnosis and better management of patients of autoimmune movement disorder.

Functional Movement Disorders in Children.

Functional movement disorders (FMDs) are not uncommon in children. The age at onset may have a bearing on the phenomenological pattern of abnormal movement, risk factors, and response to different treatment modalities in this age group. FMDs in children resemble their adult counterparts in terms of gender preponderance, but risk factors are quite different, and often influenced by cultural and demographic background. FMDs contribute to a significant proportion of acute pediatric movement disorder patients seen in emergency settings, ranging from 4.3 to 23% in different case series. The most common movement phenomenologies observed in pediatric FMDs patients are tremor, dystonia, gait disturbances, and functional tics. Various social, physical, and familial precipitating factors have been described. Common social risk factors include divorce of parents, sexual abuse, bullying at school, examination pressure, or other education-related issues, death of a close friend, relative, or family members. Physical trauma like minor head injury, immunization, tooth extraction, and tonsillectomy are also known to precipitate FMDs. The response to treatment appears to be better among pediatric patients. We aim to review FMDs in children to better understand the different aspects of their frequency, clinical features, precipitating factors, diagnosis, treatment, and outcome.

Clinical Spectrum of Drug-Induced Movement Disorders: A Study of 97 Patients.

Background: Drug-induced movement disorders (DIMDs) are commonly encountered, but an often-under-reported subgroup of movement disorders. Objectives: We aimed to highlight the spectrum of DIMDs in patients taking different groups of drugs at our movement disorder center. Methods: It is a cross-sectional descriptive study including 97 consecutive DIMDs patients diagnosed over the past two years (2017-2019). Results: The mean ± standard deviation (SD) age of our study population was 35.89 ± 17.8 years (Range-2-80 years). There were 51 males and 46 females. Different DIMDs observed included tardive dystonia (n = 41; 42.2%), postural tremor (n = 38; 39.2%), parkinsonism (n = 32; 33%), tardive dyskinesia (n = 21; 21.6%), acute dystonia (n = 10; 10.3%), neuroleptic malignant syndrome (NMS) (n = 2; 2.1%), and others [(n = 10; 10.30%) including chorea and stereotypy each in 3; acute dyskinesia in 2; and myoclonic jerks and acute akathisia each in 1 patient]. Of these 97 patients, 49 had more than one type of DIMDs while 48 had a single type of DIMDs. In our study 37 (38%) patients had received non-dopamine receptor blocking agents (non-DRBA), 30 (31%) patients had received dopamine receptor blocking agents (DRBA), and 30 (31%) patients had received both DRBA and non-DRBA. Conclusions: Tardive dystonia was the most common DIMDs observed in our study. Our DIMDs patients were younger than other reported studies. We observed a significant number of non-DRBA drugs causing DIMD in our study as compared to previous studies. Drug-induced parkinsonism (DIP) was the most common DIMDs in the DRBA group. Tardive dystonia was the most common DIMDs seen in DRBA + non-DRBA group and the second most common in the DRBA and non-DRBA group. The postural tremor was the most common DIMDs in the non-DRBA group.

Blepharospasm With Photophobia Secondary to Midbrain Tuberculoma and Thalamic Infarct.

INTRODUCTION: Blepharospasm is a type of focal dystonia and categorized into primary and secondary forms, based on whether or not a cause can be established. Secondary blepharospasm is uncommon and can be associated with underlying brain lesions. Photophobia is a prominent complaint in blepharospasm patients. We are reporting a case of secondary blepharospasm with photophobia in a patient who had underlying midbrain tuberculoma and thalamic infarcts. This type of presentation has not been reported to the best of our knowledge. CASE REPORT: A 26-year-old man presented to us with the complaint of increased blinking and involuntary closure of both eyes for 1 year. He had a past history of tubercular meningitis 16 years back when he presented with bilateral ptosis, left up gaze palsy and right hemiparesis suggestive of Weber syndrome. His magnetic resonance images of the brain were suggestive of multiple intracranial tuberculomas, thalamic infarcts, and noncommunicating hydrocephalus. Following treatment he recovered significantly with no residual neurological deficit except mild bilateral ptosis. His recent magnetic resonance images of the brain was suggestive of calcified granuloma in the midbrain and chronic left thalamic lacunar infarcts. He was treated with injection Onabotulinum toxin and his symptoms improved significantly. CONCLUSIONS: Our patient had tuberculoma in the midbrain and chronic infarcts in the thalamus, and both lesions may cause blepharospasm and photophobia independently, so it is difficult to ascertain the causative lesion in our patient. However, it is possible that these heterogenous lesions are all part of a single functionally connected brain network and further studies are required to confirm this hypothesis.

Functional Movement Disorders in Elderly.

Background: Functional movement disorders (FMDs) have been rarely described in the elderly population. Methods: This is a retrospective chart review of elderly patients with FMDs (onset >60 years) attending the movement disorders clinic at a tertiary care teaching institute in India. Results: Out of 117 patients diagnosed with FMD at our center, 18 patients had an onset after the age of 60 years. The male-to-female ratio was 10:8 and the duration of symptoms ranged from 1 day to 5 years. Social (10/18) and physical factors (5/18) with an evident temporal relationship with the onset of FMD were identified in 15 out of 18 patients. Six of them had a past history of depression, anxiety, or other psychiatric illnesses. The tremor was the most frequent phenomenology seen in 11 (61.1%) patients, followed by dystonia in seven (38.8%), choreoballism and tics in two each, and hemifacial spasm and functional gait in one each. Seven patients had more than one phenotype. Discussion: Tremor was the most frequent movement disorder seen in our patients with FMD. Surprisingly, tics (n = 2) and choreoballistic (n = 2) movements were also found in our patients with FMD, which has not been reported previously in an elderly population. Both physical and social factors were identified preceding the development of FMDs in majority of our patients.