[Drug-induced movement disorders : nosology and treatment]. / Mouvements anormaux iatrogènes : aspects nosologiques et thérapeutiques.

Movements disorders are frequently encountered in general practice and emergency departments and are in many cases of iatrogenic origin. Dopamine D2 receptor blocking agents (DRBA), mainly neuroleptics, are most often incriminated. These drug-induced movement disorders (DIMD) can be classified according to the kinetics of the manifestations (acute DIMD and tardive syndromes), the phenomenology of the abnormal movements observed or depending on the pharmacological agent involved. The diagnosis is based on the time course of the events, clinical examination and meticulous anamnesis of the patient's previous and current treatments. Management is always based on the interruption of the suspected causal treatment when possible. Some cases have a severe prognosis and require immediate treatment.

Les mouvements anormaux sont fréquemment rencontrés en médecine générale et aux urgences et sont, dans de nombreux cas, d'origine iatrogène. Les molécules les plus souvent incriminées sont les agents bloqueurs des récepteurs dopaminergiques D2 (DRBA) et principalement les neuroleptiques. Ces mouvements anormaux iatrogènes (MAI) peuvent être classés selon la cinétique des manifestations (MAI aigus et syndromes tardifs), la sémiologie des mouvements observés, ou encore, selon l'agent pharmacologique en cause. Le diagnostic repose sur le décours temporel des manifestations, l'examen clinique et une anamnèse fouillée des traitements antérieurs et actuels du patient. La prise en charge repose toujours sur l'arrêt du traitement causal quand cela est possible. Il existe des situations urgentes grevées d'un pronostic sévère et redevables d'un traitement rapide.

How to face the hemifacial spasm: challenges and misconceptions.

Hemifacial spasm (HFS) is characterised by intermittent, brief or sustained, repetitive contractions of the muscles innervated by one facial nerve. It is one of the most frequent movement disorders affecting the face. However common and allegedly straightforward to diagnose, it might reveal as a challenge for clinicians in various situations. Indeed, it often needs prior exclusion of many other movement disorders affecting the face, with frequent phenomenological overlaps with blepharospasm, post-facial palsy, facial motor tics, etc. The clinical diagnosis shall be supported by modern brain imaging techniques, and sometimes electromyography, as some particular aetiologies may require specific treatment. Primary forms are associated with vascular compression of the ipsilateral seventh cranial nerve, whereas secondary forms can be caused by any injury occurring on the facial nerve course. This article proposes a global and organised approach to the diagnosis, and the ensuing therapeutic options, as many practitioners still use some inefficient medications when they encounter a case of facial spasm.

[Functional neurological disorders: gait and movement disorders]. / Troubles neurologiques fonctionnels : marche et mouvements anormaux.

Functional neurological disorders consist of a group of neurological symptoms and syndromes for which a known "organic" cause cannot be identified. They still represent one of the most difficult diagnostic challenge for the neurologist, who can only rely on clinical criteria. Functional gait and movement disorders represent an important subgroup of these conditions and a frequent reason for consultation. The neurobiological basis of these manifestations remains poorly understood despite the progress of functional neuroimaging. Beyond the diagnosis process, its communication to the patient and its meaning represent another challenge, which requires tactful explanations as a prerequisite to a successful management.

Les troubles neurologiques fonctionnels constituent un ensemble de symptômes et syndromes neurologiques dont une cause «organique¼ ne peut être démontrée. Ils représentent toujours actuellement un des défis diagnostiques le plus difficile pour le neurologue dès lors qu'il ne peut s'appuyer que sur des critères cliniques. Les troubles de la marche et les mouvements anormaux fonctionnels constituent un sous-groupe significatif de ces affections et un motif fréquent de consultation. Les bases neurobiologiques de ces manifestations demeurent largement incomprises en dépit des progrès de la neuroimagerie fonctionnelle. Au-delà du processus diagnostique, l'annonce au patient du diagnostic et de sa signification impose une expertise et un soin particulier parce que participant à la démarche thérapeutique.

Multimodal imaging of a patient with RAB39B mutation.

Mutations in RAB39B gene have been linked to intellectual deficiency associated with parkinsonism, also referred as to Waisman syndrome. As it appears to be a very rare cause of Parkinson Disease (PD), with only few cases described in the literature, the typical clinical and radiological features are yet to be determined. In this article, we report and illustrate multimodal brain imaging by computed tomography, magnetic resonance imaging, transcranial ultrasound (US), dopamine transporter single photon emission computed tomography and [18F]-fluorodeoxyglucose positron emission tomography ([18F]FDG-PET) in a 37-year-old man with PD features and mild mental retardation harboring a new RAB39B mutation. We then propose a comparison with data previously published regarding neuroimaging in this condition and present a summary of previous imaging reports. If our patient's results partly support previously described radiological features, they also highlight potential new characteristics of this rare syndrome. To the best of our knowledge, [18F]FDG-PET and transcranial US have never been reported before in this condition. This is therefore the first multimodal brain imaging description of a patient presenting RAB39B mutation.

Parkinson's disease multimodal imaging: F-DOPA PET, neuromelanin-sensitive and quantitative iron-sensitive MRI.

Parkinson's disease (PD) is a neurodegenerative synucleinopathy characterized by the degeneration of neuromelanin (NM)-containing dopaminergic neurons and deposition of iron in the substantia nigra (SN). How regional NM loss and iron accumulation within specific areas of SN relate to nigro-striatal dysfunction needs to be clarified. We measured dopaminergic function in pre- and postcommissural putamen by [18F]DOPA PET in 23 Parkinson's disease patients and 23 healthy control (HC) participants in whom NM content and iron load were assessed in medial and lateral SN, respectively, by NM-sensitive and quantitative R2* MRI. Data analysis consisted of voxelwise regressions testing the group effect and its interaction with NM or iron signals. In PD patients, R2* was selectively increased in left lateral SN as compared to healthy participants, suggesting a local accumulation of iron in Parkinson's disease. By contrast, NM signal differed between PD and HC, without specific regional specificity within SN. Dopaminergic function in posterior putamen decreased as R2* increased in lateral SN, indicating that dopaminergic function impairment progresses with iron accumulation in the SN. Dopaminergic function was also positively correlated with NM signal in lateral SN, indicating that dopaminergic function impairment progresses with depigmentation in the SN. A complex relationship was detected between R2* in the lateral SN and NM signal in the medial SN. In conclusion, multimodal imaging reveals regionally specific relationships between iron accumulation and depigmentation within the SN of Parkinson's disease and provides in vivo insights in its neuropathology.

Anesthetic Management of a Child With Rapid-Onset Dystonia-Parkinsonism (DYT12-ATP1A3): A Case Report.

Rapid-onset dystonia-parkinsonism also known as DYT12-ATP1A3 is an extremely rare neurological disease. Patients develop dystonia, bradykinesia, postural instability, dysarthria, and dysphagia. Injection of botulinum toxin is the first-choice treatment for focal dystonia. We report the case of a 14-year-old patient diagnosed with rapid-onset dystonia-parkinsonism who was scheduled for injection of botulinum toxin in his upper limbs under general anesthesia. To our knowledge, there is no previous report about the anesthetic management of patients with rapid-onset dystonia-parkinsonism.

Cosmetic Injection of Botulinum Toxin Unmasking Subclinical Myasthenia Gravis: A Case Report and Literature Review.

Cosmetic or therapeutic use of botulinum toxin type A (BoNT-A) is usually safe but can rarely cause iatrogenic botulism. Iatrogenic botulism and myasthenia gravis (MG) share similar clinical features, because both BoNT-A and anti-acetylcholine receptorantibodies impair neuromuscular transmission. We report a patient who underwent cosmetic BoNT-A injection and later developed serious local and systemic adverse reactions. The peculiarity of this case is that a latent seropositive MG was eventually discovered, suggesting that both iatrogenic botulism and MG contributed to the clinical picture. This patient is one of the less than 10 reported cases worldwide in whom MG was unmasked by BoNT-A injection. He is the first to be assessed in detail by single-fiber electromyography. This case emphasizes the risk associated with BoNT-A injection in patients with subclinical impairment of neuromuscular transmission and prompts the search for MG in case of exaggerated response.

NMOSD with anti-MOG antibodies following anti-TNFα therapy: A case report.

Tumor necrosis factor α (TNFα) inhibitors are highly effective and a therapeutic choice for several inflammatory diseases. Their broad and long-term use is associated with a growing number of paradoxical autoimmune events including demyelinating lesions of the central nervous system (CNS). We report and discuss a case of neuromyelitis optica spectrum disorder (NMOSD) with positive myelin oligodendrocyte glycoprotein antibodies (MOG-IgG1) following anti-TNFα therapy for a pustular psoriasis.

Correlation between deep brain stimulation effects on freezing of gait and audio-spinal reflex.

OBJECTIVE: A network of cortical, subcortical and brainstem structures might be involved in freezing of gait (FOG). Subthalamic nucleus (STN) deep brain stimulation (DBS) could modulate this network. The audio-spinal reflex (ASR), reduced in PD, but increased by treatment, can be used to further investigate that locomotor network. The aim of this study is to find whether a correlation exists between ASR and FOG in PD patients under DBS. METHODS: In 14 PD patients with STN DBS and previous FOG, ASR was recorded, with DBS switched on and off. We also assessed FOG Questionnaire (FOGQ) and Unified Parkinson's Disease Rating Scale (UPDRS) Part III. RESULTS: Switching "on" DBS increased ASR amplitude (+ 33.2% with DBS ON, p = 0.048). We also found a significant inverse correlation between FOGQ and modulation of ASR by DBS (r = -0.59, r2 = 0.35, p < 0.05). CONCLUSIONS: This study shows that the incremental effect of DBS on ASR is greater in PD patients with less severe FOG. SIGNIFICANCE: This study shows a link between electrophysiological and clinical data about gait control. It might contribute to better understand why some DBS patients report heavy FOG and others do not. ASR might be used to evaluate or maybe predict the effect of stimulation parameters changes on FOG.