Myoclonus: Differential diagnosis and current management

Myoclonus classically presents as a brief (10-50 ms duration), non-rhythmic jerk movement. The etiology could vary considerably ranging from self-limited to chronic or even progressive disorders, the latter falling into encephalopathic pictures that need a prompt diagnosis. Beyond the etiological classification, others evaluate myoclonus' body distribution (i.e., clinical classification) or the location of the generator (i.e., neurophysiological classification); particularly, knowing the anatomical source of myoclonus gives inputs on the observable clinical patterns, such as EMG bursts duration or EEG correlate, and guides the therapeutic choices. Among all the chronic disorders, myoclonus often presents itself as a manifestation of epilepsy. In this context, myoclonus has many facets. Myoclonus occurs as one, or the only, seizure manifestation while it can also present as a peculiar type of movement disorder; moreover, its electroclinical features within specific genetically determined epileptic syndromes have seldom been investigated. In this review, following a meeting of recognized experts, we provide an up-to-date overview of the neurophysiology and nosology surrounding myoclonus. Through the dedicated exploration of epileptic syndromes, coupled with pragmatic guidance, we aim to furnish clinicians and researchers alike with practical advice for heightened diagnostic management and refined treatment strategies. PLAIN LANGUAGE SUMMARY: In this work, we described myoclonus, a movement characterized by brief, shock-like jerks. Myoclonus could be present in different diseases and its correct diagnosis helps treatment.

Spinal Segmental Myoclonus in Primary Progressive Multiple Sclerosis

Background

A wide variety of associated movement disorders has been described in multiple sclerosis.

Phenomenology Shown

A 57-year-old woman with primary progressive multiple sclerosis developed spinal segmental myoclonus associated with focal myelitis.

Educational Value

Movement disorders in multiple sclerosis are phenomenologically diverse and have varied pathophysiological mechanisms, making it essential to identify them to initiate appropriate treatment.

Expanding the Spectrum of Diabetic Striatopathy: Insights from a Case of Hyperglycemia-Induced Propriospinal Myoclonus

This video abstract delves into the expanded definition of diabetic striatopathy, linked initially to hyperglycemia-induced choreoballism and striatal hyperintensity on magnetic resonance imaging, but now recognized to encompass a broader range of acute onset, non-choreoballistic movement disorders in diabetes mellitus, including tremors, hemifacial spasm, parkinsonism, different types of myoclonus, dystonia, restless leg syndrome, ataxia, and dyskinesias. We report the case of a 45-year-old female patient with type-2 diabetes mellitus who developed propriospinal myoclonus, characterized by painless, involuntary jerky movements of the bilateral lower limbs in a supine position after admission for suspected rhino-orbital mucormycosis. The abnormal movements resolved entirely following the control of her blood glucose levels, suggesting a direct correlation between hyperglycemia and the clinical picture. This case highlights the importance of considering a wide range of differential diagnoses for abnormal lower limb movements in diabetic patients, emphasizing the need for accurate identification of movement semiology, routine bedside capillary blood glucose checks, and prompt hyperglycemia management to resolve such movement disorders effectively.

Stretching induced syncope associated with myoclonic jerks in a teenage boy

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Prognostic factors in epilepsy with eyelid myoclonia (Jeavons syndrome)

PURPOSE

To describe the prognostic factors of drug resistance in 40 patients with epilepsy with eyelid myoclonia or Jeavons syndrome.

METHOD

Retrospective analysis from two French tertiary centers.

RESULTS

Forty patients were enrolled (31 females and 9 males; mean age at epilepsy onset: 6.2±3.4 years [range: 1-15 years]). Half of the patients (20/40) achieved at least a one-year remission from all seizure types. In the responders, seizure freedom was achieved after a mean 13.85±13.43 years from the onset of epilepsy (range: 1-44). The presence of intellectual disability and an earlier onset of the disease (≤5 years) were the most powerful predictors of poor seizure control (P=0.003 and P=0.005, respectively). When considering the age of onset, patients with early-onset seizures (≤5 years) presented more frequently with intellectual disabilities, psychiatric comorbidities, absences, and a major risk of refractoriness (70% versus 30%, P=0.01) than patients with onset after 5 years. At the last follow-up, 15 patients (37.5%) were taking a single drug, 16 (40%) were taking two, and seven (17.5%) were taking more than two. The most frequent drugs were valproate (23/40, 57.7%), followed by levetiracetam (16/40, 40%), and lamotrigine (14/40, 35%).

CONCLUSION

Patients with Jeavons syndrome present a high rate of pharmaco-resistance with the need for long-term treatment. Early onset of epilepsy and the presence of intellectual disability appeared to be the most relevant predictors of poor seizure control, suggesting the use of genetic tests to individualize specific etiologies and perhaps adapt the therapeutic strategy.

Post-hypoxic myoclonus; what we know and gaps in knowledge

Post-hypoxic myoclonus (PHM) is a rare neurological complication having two different variants depending on acute or chronic onset after cardiopulmonary resuscitation following cardiac arrest: myoclonic status epilepticus (MSE) and Lance-Adams syndrome (LAS) respectively. Clinical and simultaneous electro-encephalographic (EEG) and electromyographic (EMG) tracing can distinguish between the two. Anecdotal treatment with benzodiazepines and anaesthetics (in the case of MSE) have been tried. Although limited evidence is available, valproic acid, clonazepam and levetiracetam, either in combination with other drugs or alone, have shown to control epilepsy associated with LAS effectively. Deep brain stimulation is a novel and promising advance in LAS treatment.

Myoclonus in patients with COVID-19: Findings of autoantibodies against brain structures in cerebrospinal fluid

BACKGROUND AND PURPOSE

COVID-19 is associated with multiple neurological manifestations. The clinical presentation, trajectory, and treatment response for three cases of myoclonus during COVID-19 infection, with no previous neurological disease, are decsribed.

METODS

Analysis of cerebrospinal fluid from the cases using indirect immunohistochemistry.

RESULTS

Antibodies against rodent brain tissue, and similarities in staining patterns were observed, indicating the presence of antineuronal immunoglobulin G autoantibodies targeting astrocytes in the hippocampus.

CONCLUSION

Our results demontrate cerebrospinal fluid antineuronal antibodies indicating an an autoimmune involvment in the pathogenesis in COVID-19 associated myoclonus.

Long-standing myoclonic hand tremor as an isolated symptom of hypertrophic olivary degeneration

Hypertrophic olivary degeneration (HOD) is a rare condition caused by lesions of the dentato-rubro-olivary pathway, usually bilateral. We presented a case of a 64-year old male with HOD caused by a unilateral, posterior pontine cavernoma. The patient has not developed the typical palate myoclonus until recently. Isolated hand myoclonus with coexisting asterixis was present for years. This case shows unique HOD symptomatology and emphasizes the important role of MRI in the differential diagnosis of monomelic myoclonus.

Unilateral asterixis in a patient with subdural hematoma: A case of epileptic negative myoclonus

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Epilepsy with eyelid myoclonia

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Myoclonus status revealing COVID 19 infection

INTRODUCTION

At the beginning of the coronavirus virus (COVID-19) pandemic, the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV2) was thought to cause mainly respiratory symptoms, largely sparing the brain and the rest of the nervous system. However, as the knowledge about COVID-19 infection progresses and the number of COVID19-related neurological manifestations reports increases, neurotropism and neuroinvasion were finally recognized as major features of the SARS-CoV-2. Neurological manifestations involving the central nervous system are sparse, ranging from headaches, drowsiness, and neurovascular attacks to seizures and encephalitis [1]. Thus far, several cases of non-epileptic myoclonus were reported in critical patients [2,3]. Here, we report the first case of myoclonus status as the inaugural and sole symptom of COVID-19 in a conscious patient.

OBSERVATION

A 60-year-old man with unknown family history and no medical issues other than smoking one cigarette packet a day over the span of 25 years. The patient presented with 5 days of abnormal movements in bilateral arms following the COVID vaccination. They were described as brief, involuntary jerking, like in sleep starts, in the proximal part of their upper members, and his face with a regular tremor in his arms exacerbated by movements and emotion. His movement disorder worsened the second day, and he developed an abnormal gait with slurred speech, concomitantly with diarrhea. Seven days following the symptoms onset, the patient was alert. His neurological exam revealed multifocal myoclonic jerks affecting four limbs predominantly proximal, the face, and the trunk (video 1). The myoclonic jerks were sensitive to tactile and auditory stimuli, without enhanced startle response or hyperekplexia. His gait was unsteady due to severe myoclonus, without cerebellar ataxia (video 2) and he had mild dysarthria. No dysmetria at the finger-to-nose and heel-to-shin tests were found. Examination of eye movements revealed paralysis of Down-Gaze and no opsoclonus was detected. Physical exam was unremarkable, including lack of fever and meningitis signs. The electroencephalogram (EEG) did not show any abnormalities concomitant with myoclonic jerks (Fig.1). The cerebral Magnetic Resonance Imaging (MRI) was normal (Fig. 2). An extensive biological work-up including a complete blood count, a comprehensive metabolic panel, an arterial blood gas analysis, a urine drug screen, a thyroid function test, a vitamin B12, folate, and ammonia level, and HIV and syphilis serologies were inconclusive. Testing for autoimmune and paraneoplastic antineuronal antibodies including anti-NMDA-R was negative. The cerebrospinal fluid (CSF) study was unremarkable (0.3 g/l of proteinorachia, 1 white blood cell). Polymerase chain reaction (PCR) for herpes simplex virus, varicella-zoster virus, and SARS-CoV-2 in CSF was negative. However, the patient tested positive for COVID-19 through PCR for viral RNA from the nasopharyngeal swab. After the administration of 12mg/day of Dexamethasone for 3 days, along with clonazepam and levetiracetam, the patient's symptoms started improving on day 3 and he displayed a very slow but progressive recovery.

DISCUSSION

Our patient presented with acute isolated multifocal myoclonus status without cognitive impairment. These movements were prominent, spontaneous, worsened by action, and sensitive to touch and sound. The anatomical source of this myoclonus could be cortical or subcortical despite the absence of evident EEG discharges. Several diseases can cause acute myoclonus such as severe hypoxia, metabolic disturbances, and paraneoplastic syndromes. these diagnoses were ruled out in our patient. Post-vaccinal origin was also suggested, but its accountability was not proven. Thus, the two hypothetic etiologies raised were either para-infectious or infectious mechanisms in relation to SARS-Cov 2 infection. HIV, VZV, HSV, and syphilis infections were eliminated and the patient tested positive for SARS-Cov2 infection. In the literature, COVID-19-related myoclonus was reported as a complication of an already-known SARS-CoV-2 infection in about 50 patients so far. It generally occurs between 6 days and 26 days following the SARS-CoV-2 infection [2-5], and affects critical illness patients with cognitive decline, mainly from the intensive care unit [3,4]. Yet, our patient did not display any symptoms of COVID-19 infection before the occurrence of these abnormal movements. Furthermore, he had a relatively good general condition and no cognitive impairment. Several pathophysiological mechanisms were suggested regarding the COVID-19-related myoclonus. Either central nervous invasion by SARS-Cov 2 after transneuronal spread and/or auto-immune cross-reactivity reaction, are likely incriminated in the pathophysiology of most of the cases [6]. We believe that there is an inflammatory process involved with increased levels of proinflammatory cytokines and systemic inflammation, including cytokine storm or cytokine release syndrome targeting the brain and more specifically the cortex and basal ganglia [6]. Data collection in clinical registries is needed to increase our knowledge of the prevalence of neurological symptoms in patients with COVID-19 and will hopefully clarify the causal relationship between SARS-CoV-2 infection and post-COVID-19 myoclonic syndrome.

[A case of idiopathic propriospinal myoclonus accompanied by giant somatosensory evoked potential]

A 41-year-old man visited our clinic because of headache with fever, suggestive of aseptic meningitis. His headache improved in a few days. His neurological examination showed positive jolt accentuation and myoclonus of the thoracoabdominal muscles extending to extremities upon patellar tapping. His myoclonus had been occurring spontaneously from early adolescence, especially in relaxed states such as drowsiness. The myoclonus was not triggered by tactile, auditory, or visual stimulation. Polymyography revealed that the myoclonus originated around the T4 spinal level and slowly propagated both upward and downward. These findings were indicative of spontaneous and reflex propriospinal myoclonus (PSM). No abnormalities were seen on brain and spinal MRI. Furthermore, the amplitude of the cortical component of the somatosensory evoked potential (SEP) after electrical stimulation of the tibial nerve was enlarged bilaterally. It was speculated that the ascending signals from the myoclonus generator at T4 to S1 may have modulated the excitability and inhibitory function of S1 in this patient. This report may be the first case of idiopathic PSM accompanied by giant SEP.

Clinical heterogeneity in patients with myoclonus associated to COVID-19

Objective

This study aims to report the clinical heterogeneity of myoclonus in 6 patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Methods

Patient data were obtained from medical records from the University Hospital Dr. Josep Trueta, Girona, Spain.

Results

Six patients (5 men and 1 woman, aged 60–76 years) presented with different myoclonus phenotypes. All of them had a medical history of hypertension and overweight. The latency of myoclonus appearance ranged from 1 to 129 days. The phenotype most observed was generalized myoclonus. Special phenotypes such as painful legs and moving toes syndrome with jerking feet, Lazarus sign-like, action myoclonus/ataxia syndrome, and segmental myoclonus secondary to myelitis have been described too. Levetiracetam and clonazepam were medications most used successfully. Two patients died for complications not related to myoclonus.

Conclusions

Our 6 cases highlight the heterogeneity of the clinical spectrum of myoclonus associated to COVID-19 (MYaCO). MYaCO pathogenesis is suspected to be due to an immune-mediated para- or post-infectious phenomenon; nevertheless, further research is needed to elucidate this hypothesis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10072-021-05802-1.

Iliopsoas Hematomas in a Patient with Progressive Encephalomyelitis with Rigidity and Myoclonus

Progressive encephalomyelitis with rigidity and myoclonus (PERM) is a rare and severe syndrome characterized by rigidity of the limb and truncal muscles, brainstem signs, myoclonus, and hyperekplexia. Iliopsoas hematoma is a serious complication of bleeding disorders that occurs most commonly in patients with hemophilia and also in association with anti-coagulant drug treatment. We herein present a case of PERM complicated with bilateral iliopsoas hematomas. His neurological symptoms improved after immunotherapy, and thereafter the iliopsoas hematomas disappeared. Neurologists should consider iliopsoas hematomas as a serious potential complication of PERM.

Generalised myoclonus associated with COVID-19 infection

Postinfectious generalised myoclonus has been reported after many viral and bacterial infections in the past. Recently, some case reports have described it in the context of COVID-19 infection. Most patients described in these case reports are either critically ill and intubated or have concurrent respiratory symptoms. Herein, we present a case of a 79-year-old man, who was recovering from a recent COVID-19 infection, presented with isolated generalised myoclonus. The patient was treated with levetiracetam, a short course (10 days) of dexamethasone, and required extensive rehabilitation. Outpatient follow-up at 2 months suggested complete resolution of symptoms and levetiracetam was subsequently discontinued. This case highlights that generalised myoclonus can occur as a delayed complication of COVID-19 infection.

Abnormal movements in hospitalized COVID-19 patients: A case series

BACKGROUND

Abnormal movements in Covid-19 patients have been reported with varying degree of frequency, prompting neurologic consultation and additional diagnostic evaluation. We sought to evaluate the frequency and etiology of abnormal movements among hospitalized Covid-19 patients undergoing neurologic consultation.

METHODS

We retrospectively analyzed the first 50 consecutive patients with confirmed Covid-19 hospitalized at our tertiary medical care center who underwent acute inpatient neurology consultation from March 2020 through May 2020. Indication for neurologic consultation and diagnostic studies performed were identified by electronic medical record review.

RESULTS

Of the 50 initial consultation requests, 11 (22.0%) patients were evaluated for abnormal movements (nine male and two female). Myoclonus was diagnosed in 6/11 (54.5%) patients. Additionally, two patients were diagnosed with seizures (confirmed on EEG in one), while two additional patients were diagnosed with tremor (physiologic and probable functional). A single case of serotonin syndrome was also identified.

CONCLUSION

Abnormal movements observed in hospitalized Covid-19 patients can have a wide range of etiologies and were a frequent initial indication for neurologic consultation. Myoclonus was the most frequent type of abnormal movement observed. Early clinical recognition and directed diagnostic work-up is essential for accurate diagnoses in these patients.

Subacute sclerosing panencephalitis and brain stem involvement: a rare combination

Subacute sclerosing panencephalitis (SSPE) is a progressive lethal neurological inflammatory disease due to persistent, wild measles virus infection in the central nervous system that is seen most frequently in children and young adolescents. Atypical presentations are seen in up to 10% of cases. Most frequently and severely affected region in the brain is the parieto-occipital region of the brain. Less commonly involved organs are the cerebellum, basal ganglia and corpus callosum. Brainstem involvement is rare and usually occurs when other areas of brain are involved along with it. Here, we describe an unusual male patient of 15 years age, having SSPE with MRI of brain showing extensive involvement of brainstem with no significant involvement of other cortical structures of the brain. It is very rarely described in SSPE, but one should be vigilant about such involvement of brainstem and cerebellum, and SSPE should not be missed when brainstem hyperintensities are seen in MRI brain with or without other region of the brain to avoid misdiagnosis.

Neurological and Neuropsychiatric Impacts of COVID-19 Pandemic

BACKGROUND

Albeit primarily a disease of respiratory tract, the 2019 coronavirus infectious disease (COVID-19) has been found to have causal association with a plethora of neurological, neuropsychiatric and psychological effects. This review aims to analyze them with a discussion of evolving therapeutic recommendations.

METHODS

PubMed and Google Scholar were searched from 1 January 2020 to 30 May 2020 with the following key terms: "COVID-19", "SARS-CoV-2", "pandemic", "neuro-COVID", "stroke-COVID", "epilepsy-COVID", "COVID-encephalopathy", "SARS-CoV-2-encephalitis", "SARS-CoV-2-rhabdomyolysis", "COVID-demyelinating disease", "neurological manifestations", "psychosocial manifestations", "treatment recommendations", "COVID-19 and therapeutic changes", "psychiatry", "marginalised", "telemedicine", "mental health", "quarantine", "infodemic" and "social media". A few newspaper reports related to COVID-19 and psychosocial impacts have also been added as per context.

RESULTS

Neurological and neuropsychiatric manifestations of COVID-19 are abundant. Clinical features of both central and peripheral nervous system involvement are evident. These have been categorically analyzed briefly with literature support. Most of the psychological effects are secondary to pandemic-associated regulatory, socioeconomic and psychosocial changes.

CONCLUSION

Neurological and neuropsychiatric manifestations of this disease are only beginning to unravel. This demands a wide index of suspicion for prompt diagnosis of SARS-CoV-2 to prevent further complications and mortality.

Myoclonus in Patients With Coronavirus Disease 2019: A Multicenter Case Series

OBJECTIVES

To describe the risk factors for and outcomes after myoclonus in a cohort of patients with coronavirus disease 2019.

DESIGN

Multicenter case series.

SETTING

Three tertiary care hospitals in Massachusetts, Georgia, and Virginia.

PATIENTS

Eight patients with clinical myoclonus in the setting of coronavirus disease 2019.

INTERVENTIONS & MEASUREMENTS AND MAIN RESULTS

Outcomes in patients with myoclonus were variable, with one patient who died during the study period and five who were successfully extubated cognitively intact and without focal neurologic deficits. In five cases, the myoclonus completely resolved within 2 days of onset, while in three cases, it persisted for 10 days or longer. Seven patients experienced significant metabolic derangements, hypoxemia, or exposure to sedating medications that may have contributed to the development of myoclonus. One patient presented with encephalopathy and developed prolonged myoclonus in the absence of clear systemic provoking factors.

CONCLUSIONS

Our findings suggest that myoclonus may be observed in severe acute respiratory syndrome coronavirus 2 infected patients, even in the absence of hypoxia. This association warrants further evaluation in larger cohorts to determine whether the presence of myoclonus may aid in the assessment of disease severity, neurologic involvement, or prognostication.

Generalized myoclonus in COVID-19

OBJECTIVE

To report 3 patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) who developed generalized myoclonus.

METHODS

Patient data were obtained from medical records from the University Hospital "12 de Octubre," Madrid, Spain.

RESULTS

Three patients (2 men and 1 woman, aged 63-88 years) presented with mild hypersomnia and generalized myoclonus following the onset of the so-called inflammatory phase of coronavirus disease 2019 (COVID-19). All of them had presented previously with anosmia. Myoclonus was generalized with both positive and negative jerks, predominantly involving the facial, trapezius, sternocleidomastoid, and upper extremities muscles. These myoclonic jerks occurred spontaneously and were extremely sensitive to multisensory stimuli (auditive and tactile) or voluntary movements, with an exaggerated startle response. Other causes of myoclonus were ruled out, and none of the patients had undergone respiratory arrest or significant prolonged hypoxia. All of them improved, at least partially, with immunotherapy.

CONCLUSIONS

Our 3 cases highlight the occurrence of myoclonus during the COVID-19 pandemic as a post- or para-infectious immune-mediated disorder. However, we cannot rule out that SARS-CoV-2 may spread transneuronally to first- and second-order structures connected with the olfactory bulb. Further investigation is required to clarify the full clinical spectrum of neurologic symptoms and optimal treatment.

Treatment of Movement Disorder Emergencies in Autoimmune Encephalitis in the Neurosciences ICU

Immune response against neuronal and glial cell surface and cytosolic antigens is an important cause of encephalitis. It may be triggered by activation of the immune system in response to an infection (para-infectious), cancer (paraneoplastic), or due to a patient's tendency toward autoimmunity. Antibodies directed toward neuronal cell surface antigens are directly pathogenic, whereas antibodies with intracellular targets may become pathogenic if the antigen is transiently exposed to the cell surface or via activation of cytotoxic T cells. Immune-mediated encephalitis is well recognized and may require intensive care due to status epilepticus, need for invasive ventilation, or dysautonomia. Patients with immune-mediated encephalitis may become critically ill and display clinically complex and challenging to treat movement disorders in over 80% of the cases (Zhang et al. in Neurocrit Care 29(2):264-272, 2018). Treatment options include immunotherapy and symptomatic agents affecting dopamine or acetylcholine neurotransmission. There has been no prior published guidance for management of these movement disorders for the intensivist. Herein, we discuss the immune-mediated encephalitis most likely to cause critical illness, clinical features and mechanisms of movement disorders and propose a management algorithm.

Biotinidase deficiency in a newborn

INTRODUCTION

Biotinidase deficiency is an inherited disorder of biotin metabolism that is untreated may present within the first few month of life.

OBJECTIVE

We report the exceptional observation of a biotinidase deficiency in Morocco. The rarity of this pathology, its age of onset, its mode of revelation and the lack of treatment in Morocco make the particularity of this observation.

OBSERVATION

A newborn child born from a 24-year-old mother, followed by an estimated pregnancy of 37 weeks of amenorrhea according to the Farr score (morphological maturation score used for the dating of the pregnancy term). The infant presented at 7 days of life with a cutaneous-mucous eruption with icithiosic dry erythroderma of interest to the trunk, the face, the scalp associated with alopecia and depilation of the eyebrow. The biotinoidase deficiency was confirmed by its low serum concentration at 49 nka / l. The newborn died at 20 days of life before starting the specific treatment.

CONCLUSION

Biotinidase deficiency is a rare condition requiring early screening and rapid management. The delay in diagnosis and the unavailability of treatment in Morocco can have fatal consequences.

Stiff limb syndrome with lower limb myoclonus: A case report

RATIONALE

stiff limb syndrome (SLS) is a variant of stiff-man syndrome, primarily affecting a specific limb. Its diagnosis has always been challenging due to the lack of a specific confirmation test. We present a rare case of a patient with lower limb myoclonus and rigidity.

PATIENT CONCERNS

A 53-year-old male presented with a sudden onset of progressive left lower extremity myoclonus and muscle rigidity for 3 days. He rapidly showed signs of right lower limb involvement with severe joint stiffness and inability to walk.

DIAGNOSIS

The symptoms nature, physical examination, careful elimination of differential diagnosis suggested a diagnosis of stiff limb syndrome.

INTERVENTIONS

Intravenous infusion of gamma globulin 0.4 mg/kg coupled with baclofen and clonazepam were given after admission. He also received an injection of botulinum toxin A to relieve his muscle stiffness.

OUTCOMES

The patients' condition improved after the initial treatment with complete disappearance of muscle twitching. Further improvements were seen later on after the local administration of botulinum toxin A.

LESSONS

Stiff limb syndrome shares the same complex symptoms with many other conditions. Its diagnosis relies heavily on clinical presentations and on ruling out other conditions. However, unusual symptoms such as myoclonus can occur in few cases and together with the rarity of the condition, the prevalence of misdiagnosis is high. Therefore, being aware and recognizing the signs and symptoms is crucial for proper management. Additionally, EMG is a very important test if the present condition is suspected. However, a negative EMG result or a negative anti-glutamic acid decarboxylase antibody test should not exclude SLS diagnosis.

Recognizing Movement Disorder Emergencies - A Practical Review For Non-Neurologist

Neurology still remains one of the most underserved specialties of medicine in Pakistan with roughly one neurologist per million people. Movement disorders (MD) are neurological problems that interfere with patient's motor abilities and diagnosis is typically clinical. In this review, we describe a practical approach to common MD emergencies that may be encountered by a non-neurologist physician, emphasizing on formulating a working diagnosis and their immediate management. Movement disorder emergencies can be classified based on MD phenomenology and we will provide a brief overview of dystonia including acute dystonic reaction, PAID syndrome and dystonic storm; chorea, myoclonus including serotonin syndrome and startle disease; and rigidity including neuroleptic malignant syndrome and malignant hyperthermia.

Spinal myoclonus following neuraxial anesthesia: a literature review

Spinal myoclonus (SM) is a rare neurologic movement disorder following neuraxial anesthesia (NA). SM following NA (SM-NA) has insufficient clinical information and its pathogenesis remains to be elucidated. The aim of this review article was to summarize the past cases and consider SM-NA pathophysiology. Based on our PubMed search, it was revealed that SM-NA develops within several hours after neuraxial local anesthetic (LA) administration and resolves in a day without leaving neurologic compilations. It occurs primarily in the lower extremities, but can sometimes spread upward and affect the upper extremities and trunk. Although statistical adjustments are indispensable, analysis of the previous cases provided important facts that seem to be related with the mechanism of SM-NA. The frequently used LAs for spinal anesthesia were hyperbaric. SM-NA occurrence was more frequent in women. After initiation of spinal anesthesia, intrathecal hyperbaric LA distributes cephalad. In the LA elimination process, the large concentration differences in intrathecal LA may induce the partially functioning spinal neurons, resulting in myoclonus generation. The morphological features of the lumbar spine in women can predispose to a higher LA concentration difference. SM-NA is an unpredictable and rare neural complication following NA and should be confirmed by basic experiments and large-scale researches.

Apport de l'IRM dans la maladie de Creutzfeldt-Jakob: à propos d'un cas

La maladie de Creutzfeld-Jacob (MCJ) est une affection très rare et fatale qui atteint le système nerveux central. Elle est caractérisée par une détérioration mentale aboutissant à une démence progressive, une symptomatologie pyramidale et extra-pyramidale ainsi que des myolclonies. Un diagnostic précoce est essentiel pour prévenir la transmission interhumaine. Nous rapportons le cas d'un patient âgé de 62 ans chez qui le diagnostic de MCJ sporadique a été retenu, en se basant sur le tableau clinique fait de syndrome démentiel avec myoclonies précédées de troubles du comportement, des hallucinations et de dépression, et sur les données de l'IRM encéphalique qui a montré des hyper signaux au niveau du striatum et au niveau cortical en séquences pondérées Flair et diffusion.

A case report of rigidity and recurrent lower limb myoclonus: progressive encephalomyelitis rigidity and myoclonus syndrome, a chameleon

BACKGROUND

Progressive encephalomyelitis with rigidity and myoclonus (PERM) syndrome is a rare neurological condition. Its clinical characteristics include axial and limb muscle rigidity, myoclonus, painful spasms and hyperekplexia. Diagnosis of this disease can be very challenging and optimal long-term treatment is unclear.

CASE PRESENTATION

We report a case of a 62 year old patient admitted for repetitive myoclonus and rigidity in the lower limbs progressing since 10 years, associated with a fluctuating encephalopathy requiring stays in Intensive Care Unit. Multiple diagnostics and treatment were proposed, unsuccessfully, before the diagnosis of PERM syndrome was established. In association with the clinical presentation, a strong positive result for GAD (glutamic acid decarboxylase) antibodies lead to the diagnosis of PERM syndrome.

CONCLUSIONS

PERM syndrome is a rare disease and its diagnosis is not easy. Once the diagnosis is established, the correct treatment should follow and could be lifesaving, regardless of a delayed diagnosis. Maintenance of long-term oral corticotherapy is suggested to prevent relapses.

Spinal myoclonus: a rare presentation of cervical myelopathy

Myoclonus describes a movement disorder characterised by brief, abrupt and involuntary contractions of muscles or groups of muscles, usually associated with intracranial lesions, with limited evidence linking it to spinal pathologies. The pathophysiology of spinal myoclonus is extensive and multifactorial. Infection, intramedullary and extramedullary space-occupying lesions, trauma, vascular abnormalities, degenerative processes and cervical spondylosis have been implicated with the disease, the latter been associated with cervical stenosis with no reported cases linking it to an underlying cervical disc herniation. Although medical therapy with clonazepam, levetiracetam, valproate, tetrabenazine hydrochloride and spinal block injections has been equivocal, spinal myoclonus secondary to disc herniation requires surgical intervention. This report describes a case of segmental spinal myoclonus, secondary to a herniated cervical intervertebral disc. After corpectomy and a cage-augmented fusion technique, the myoclonic symptoms resolved. To our knowledge, this was the first report to describe the successful management of discogenic spinal myoclonus with spinal surgery.

Myoclonic movement after general anesthesia: A case report and review of the literature

RATIONALE

Myoclonic movement is a rare side effect after general anesthesia. Since we use various intravenous agents during general anesthesia recently, it is troublesome to find out the exact cause of this neurologic complication.

PATIENT CONCERNS

A 31-year-old female patient without any past medical history underwent hip arthroscopic surgery under general anesthesia.

DIAGNOSES

Although there was no specific event during the operation, she showed a sudden myoclonic movement confined to left upper extremity in recovery room.

INTERVENTIONS

We administered anticonvulsant agents intrvenously, the myoclonus was stopped shortly but recurred over again. As we stopped the patient-controlled analgesia due to nausea, the symptom halted.

OUTCOMES

There was no significant abnormality in electroencephalography or brain diffusion magnetic resonance imaging, which was taken after the event.

LESSONS

Clinicians should carefully consider the pharmacologic characteristics and neurologic adverse effects of all administered agents when myoclonus occurs after general anesthesia.

[Myoclonus as a movement disorder]

Myoclonus is often a diagnostic and therapeutic challenge due to its broad phenomenological variability and limited therapeutic options. This article gives a short survey and characterizes in detail two common types of myoclonus, cortical myoclonus and reticular reflex myoclonus. Clinical testing and electrophysiological investigations provide relevant local diagnostic indications for the generating structure(s). Such indications would influence not only the strategies of neuroimaging and laboratory investigations aimed at clarifying the underlying cause but also the selection of drugs to suppress myoclonus.

Signs and symptoms preceding the diagnosis of Alzheimer's disease: a systematic scoping review of literature from 1937 to 2016

OBJECTIVE

Late diagnosis of Alzheimer's disease (AD) may be due to diagnostic uncertainties. We aimed to determine the sequence and timing of the appearance of established early signs and symptoms in people who are subsequently diagnosed with AD.

METHODS

We used systematic review methodology to investigate the existing literature. Articles were reviewed in May 2016, using the following databases: MEDLINE, PsycINFO, CINAHL, British Nursing Index, PubMed central and the Cochrane library, with no language restriction. Data from the included articles were extracted independently by two authors and quality assessment was undertaken with the quality assessment and diagnostic accuracy tool-2 (QUADAS tool-2 quality assessment tool).

RESULTS

We found that depression and cognitive impairment were the first symptoms to appear in 98.5% and 99.1% of individuals in a study with late-onset AD (LOAD) and 9% and 80%, respectively, in early-onset AD (EOAD). Memory loss presented early and was experienced 12 years before the clinically defined AD dementia in the LOAD. However, the rapidly progressive late-onset AD presented predominantly with 35 non-established focal symptoms and signs including myoclonus (75%), disturbed gait (66%) and rigidity. These were misdiagnosed as symptoms of Creutzfeldt-Jacob disease (CJD) in all the cases. The participant with the lowest mini-mental state examination score of 25 remained stable for 2 years, which is consistent with the score of the healthy family members.

CONCLUSIONS

The findings of this review suggest that neurological and depressive behaviours are an early occurrence in EOAD with depressive and cognitive symptoms in the measure of semantic memory and conceptual formation in LOAD. Misdiagnosis of rapidly progressive AD as CJD and the familial memory score can be confounding factors while establishing a diagnosis. However, the study was limited by the fact that each one of the findings was based on a single study.