Movement disorders associated with pediatric encephalitis.

New onset movement disorders are a common clinical problem in pediatric neurology and can be infectious, inflammatory, metabolic, or functional in origin. Encephalitis is one of the more important causes of new onset movement disorders, and movement disorders are a common feature (~25%) of all encephalitis. However, all encephalitides are not the same, and movement disorders are a key diagnostic feature that can help the clinician identify the etiology of the encephalitis, and therefore appropriate treatment is required. Movement disorders are a characteristic feature of autoimmune encephalitis such as anti-NMDAR encephalitis, herpes simplex virus encephalitis-induced autoimmune encephalitis, and basal ganglia encephalitis. Other rarer autoantibody-associated encephalitis syndromes with movement disorder associations include encephalitis associated with glycine receptor, DPPX, and neurexin-3 alpha autoantibodies. In addition, movement disorders can accompany acute disseminated encephalomyelitis with and without myelin oligodendrocyte glycoprotein antibodies. Extremely important infectious encephalitides that have characteristic movement disorder associations include Japanese encephalitis, dengue fever, West Nile virus, subacute sclerosing panencephalitis (SSPE), and SARS-CoV-2 (COVID-19). This chapter discusses how specific movement disorder phenomenology can aid clinician diagnostic suspicion, such as stereotypy, perseveration, and catatonia in anti-NMDAR encephalitis, dystonia-Parkinsonism in basal ganglia encephalitis, and myoclonus in SSPE. In addition, the chapter discusses how the age of the patients can influence the movement disorder phenomenology, such as in anti-NMDAR encephalitis where chorea is typical in young children, even though catatonia and akinesia is more common in adolescents and adults.

The spectrum of psychiatric manifestations in subacute sclerosing panencephalitis: A systematic review of published case reports and case series.

Data related to psychiatric manifestations in subacute sclerosing panencephalitis (SSPE) is currently available only in the form of isolated case reports. In this systematic review, we evaluated the spectrum of psychiatric manifestations and their impact on the course and outcome of SSPE. Data were obtained from 4 databases (PubMed, Embase, Scopus, and Google Scholar), with the most recent search conducted on March 27, 2023. The PRISMA guidelines were followed, and the PROSPERO registration number for the protocol is CRD42023408227. SSPE was diagnosed using Dyken's criteria. Extracted data were recorded in an Excel spreadsheet. To evaluate the quality of the data, the Joanna Briggs Institute Critical Appraisal tool was employed. Our search resulted in 30 published reports of 32 patients. The mean age was 17.9 years. Schizophrenia, catatonia, and poorly characterized psychotic illnesses were the 3 most common psychiatric presentations that were seen in 63% (20/32) of cases. Catatonia was seen in 4 patients. Affective disorders, mania, and depression were reported among 22% (7/32) cases. In approximately 81% (26/32) cases, the course of SSPE was acute fulminant. Treatment with antipsychotic drugs had poor or no response. Out of 17 patients, who received antipsychotic drugs, 6 patients noted severe extrapyramidal adverse effects. SSPE often masquerades as a psychiatric disorder. Unresponsive psychiatric symptoms, early extrapyramidal signs, and progressive encephalopathy indicate SSPE.

Status Dystonicus in Subacute Sclerosing Panencephalitis-A Rare Presentation in Emergency.

Dystonia has been described in a few cases with SSPE, but there are only very few reports with status dystonicus and none from South India. Here, we report a six-year-old child presenting with severe dystonic posturing of all four limbs and trunk for 10 days duration following a febrile illness and initially treated elsewhere as viral encephalitis. Scalp EEG showed periodic high-amplitude slow wave discharges. MRI brain showed T2/FLAIR hyperintensity in bilateral frontal, left parietal, and deep white matter, extending across the corpus collosum with diffuse cerebral atrophy. The titer for IgG antibodies to measles virus by ELISA was 1:625, suggestive of SSPE. With medications, dystonia used to subside transiently; however, the patient had worsening of symptoms and showed gradual deterioration.

Measles Virus and the Central Nervous System: An Update.

MEASLES VIRUS AND ASSOCIATED CENTRAL NERVOUS SYSTEM: Sequelae Renee Buchanan, Daniel J. Bonthius Seminars in Pediatric Neurology Volume 19, Issue 3, September 2012, Pages 107-114 Worldwide, measles remains one of the most deadly vaccine-preventable diseases. In the United States, enrollment in the public schools requires that each child receives 2 doses of measles-containing vaccine before entry, essentially eliminating this once endemic disease. Recent outbreaks of measles in the United States have been associated with importation of measles virus from other countries and subsequent transmission to intentionally undervaccinated children. The central nervous system complications of measles can occur within days or years of acute infection and are often severe. These include primary measles encephalitis, acute postinfectious measles encephalomyelitis, measles inclusion body encephalitis, and subacute sclerosing panencephalitis. These measles associated central nervous system diseases differ in their pathogenesis and pathologic effects. However, all involve complex brain-virus-immune system interactions, and all can lead to severe and permanent brain injury. Despite better understanding of the clinical presentations and pathogenesis of these illnesses, effective treatments remain elusive.

Fatal subacute sclerosing panencephalitis in an 8-year-old male: a case report.

Subacute sclerosing panencephalitis (SSPE) is a chronic slow progressive neurodegenerative disease that is often associated with measles complications. The disease is characterized by seizures, behavioral changes, motor deficit and eventually death. In this case report we discuss the case of an 8-year-old male who developed SSPE and was presented to our hospital with a history of generalized tonic colonic convulsion followed by gait abnormality, episodes, abnormal behaviors, and cognitive regression. On clinical exploration, the child had a history of measles at 8 months of age and meningitis at 18 months. The electroencephalogram (EEG) investigation showed high amplitude spikes, with focal seizure and slowing, while the magnetic resonance imaging reveal signals synonymous with high fluid-attenuated inversion recovery (FLAIR), both of which are consistent with probable SSPE. The case was managed symptomatically; until his parents decided to take him back home, after which his condition deteriorated, and he sadly died. To the best of our knowledge, this is the first recorded case of SSPE in Mogadishu, Somalia. Hence, the need to further investigation to better understand the incidence of the disease in the population and propose better ways of managing the condition.

Immune-dysregulation in subacute sclerosing panencephalitis: An exploratory case-control study.

Subacute sclerosing panencephalitis (SSPE) is a chronic progressive neurological condition caused by a defective measles virus. It is postulated that immune-dysregulation might result in persistent infection (immune evasion) as well as initiation of autoimmune phenomenon (via natural killer cells) leading to panencephalitis. The primary objective of this case-control study was to analyse the pattern of immune dysregulation in cases with SSPE. The secondary objective was to assess the correlation between the measured immunological variables and disability/death at 6 months. This was an exploratory case-control study conducted at a tertiary-care referral-facility from January 2020 to September 2021. Thirty consecutive patients fulfilling the Dyken's criteria for SSPE and 30 age-and-sex-matched healthy controls were enrolled. Immunological profile constituted by lymphocyte subset analysis, immunoglobulin levels and complement levels were done in all cases and controls. Cases were staged as per Jabbour's system; disability was assessed using the modified Rankin Scale (mRS). Patients with SSPE had a mean age of 14.76 years (±6.9 years). There were 25 males and 5 females; 6.7% cases belonged to Jabbour's first stage, 40% to second stage and 53.3% to third stage. At least 1/4th had evidence of measles vaccination. Levels of absolute lymphocyte count, B-cells, T cells, helper T-cells, and cytotoxic T-cells were significantly higher in cases. IgG, IgM, and IgE levels were significantly higher while IgD levels were significantly lower in cases. At baseline, 13.3% of cases had a mRS score of 0-2 and 86.7% had a score of 3-6; at 6 months 10% had a mRS score 0-2 (favorable outcome) while 90% had a mRS score 3-6 (poor outcome). Higher IgE levels were found to correlate significantly with favorable outcome. Immune-dysregulation may play a significant role in shaping one's response to measles infection as well as in determining vaccine-efficacy.

Spectral Domain Optical Coherence Tomography Findings of Subacute Sclerosing Panencephalitis Presenting with Macular Necrotizing Retinitis: A Case Report.

PURPOSE: To report the fundus photographs and spectral domain optical coherence tomography (SD-OCT) findings of a patient with subacute sclerosing panencephalitis (SSPE) presenting merely with ocular symptoms. CASE REPORT: A 20-year-old patient presented with sudden loss of vision in the left eye (LE). Fundus photograph showed a yellow lesion in the macula and SD-OCT showed increased reflectivity of the inner retinal layers. Disorganization of the necrotizing retinal layers in the LE gradually progressed to the atrophic retina. Then, visual complaints began in the right eye (RE) accompanied by neurological symptoms. SD-OCT revealed the inner and outer plexiform layers edema and interruption of the ellipsoid zone in RE. Fundus photographs showed macular atrophy for both eyes on the day patient died. CONCLUSION: This case report demonstrates the SD-OCT findings of SSPE retinitis with close follow-up from the acute retinitis to the total atrophic macula. These unique findings may be considered as characteristical for the diagnosis.

Cortical activation and motor body representations in a patient with subacute sclerosing panencephalitis.

The current neuroimaging study investigated the sensorimotor maps during hand, feet and lips movements at one year after diagnosis of of subacute sclerosing panencephalitis (SSPE) in a 17 years-old patient. A lesion prediction algorithm showed that the posterior thalamic radiations, the splenium of the corpus callosum, the posterior and superior corona radiate, and the cingolum, showed a high lesion probability. Comparing the fMRI activations of the left and right hemisphere, we found that the representation of the left hand movement was more inferior/anterior and less represented than the representation of the right one; and the representation of the right foot movement was more superior, less represented than the representation of the left one and poorly activated at the predefined statistical threshold. The fMRI results are in line with the clinical report, describing an asymmetrical distribution of the periodic stereotyped myoclonic jerks, which mainly occurred for the left arm/hand and for the right leg/foot. This is the first fMRI study investigating the representation of the body parts in patients with SSPE. Results show that in SSPE the hyper-stimulation of the motor system (dedicated to the arm/hand and leg/foot more involved by the occurrence of the jerks) is accompanied by an under-activation of the corresponding motor representations in coincidence with voluntary movements.

Spectrum of Movement Disorders Among Children With Subacute Sclerosing Panencephalitis: A Cross-Sectional Study.

Background: Subacute sclerosing panencephalitis is a progressive devastating condition due to persistence of mutant measles virus, affecting children and adolescents, characterised by myoclonus, seizures, and neuropsychiatric issues. Movement disorders apart from myoclonus are reportedly uncommon. We aimed to describe frequency and proportion of movement disorders among children with subacute sclerosing panencephalitis, hypothesizing that these occur more frequently than previously reported. Methods: In this cross-sectional study, we enrolled children with subacute sclerosing panencephalitis between 1 month and 18 years of age who fulfilled the diagnosis of subacute sclerosing panencephalitis as per modified Dyken criteria, and examined them for movement disorders. We also assessed their clinical profile and disease severity via Jabbour staging and modified Rankin Scale score. We compared demographic, clinical, and laboratory features of children with and without movement disorders. Results: We enrolled 50 children (36 males; 72%) (age range 1.5-14 years). Of these, 28 (56%) had movement disorders. Among movement disorders, the most frequent was myoclonus (92%), followed by ataxia (9; 18%), chorea-athetosis (7; 14%), dystonia (6; 12%), tremor (4; 8%), repetitive behavior (4; 8%), and parkinsonism (3; 6%). Movement disorders were the presenting feature of subacute sclerosing panencephalitis among 7 children. There were no significant differences in clinical or laboratory features among children with and without movement disorders. Conclusions: Movement disorders were frequent in subacute sclerosing panencephalitis. Hyperkinetic disorders were dominant. Dystonia and chorea-athetosis occurred more commonly among nonmyoclonus movement disorders. Movement disorders may manifest even in earlier stages of subacute sclerosing panencephalitis and may be the heralding feature. Recognition of these features is important to plan management and reduce morbidity.

Progression of myoclonus subtypes in subacute sclerosing panencephalitis.

OBJECTIVES: Diagnostic criteria of subacute sclerosing panencephalitis (SSPE) include myoclonus, a well-recognized clinical feature. Here, we studied the electrophysiological features of myoclonus with regards to disease staging in SSPE patients. METHODS: We included 10 patients diagnosed with SSPE between 2010 and 2018, along with 21 healthy subjects. All participants had detailed electrophysiological evaluation including polymyographic analysis, blink reflex after trigeminal stimulation, auditory startle response, startle response after somatosensory stimuli, F-waves, and long-loop reflexes. Clinical findings were retrieved from the medical records. RESULTS: Patients were categorized into Gascon stage 2B (n = 5, 50%), 2A (n = 2, 20%), 3B (n = 2, 20%) and 4A (n = 1, 10%) at the time of electrophysiological evaluation. Two patients had cortical myoclonus, four had possible cortico-subcortical myoclonus, and four had brainstem myoclonus. Patients were categorized into Gascon stages 2a and 2b had possible cortico-subcortical myoclonus (85.7%). However, none of the patients with stage 3b or 4a had possible cortico-subcortical subtype but all had the brainstem subtype. CONCLUSION: Association was seen between subtypes of myoclonus and clinical staging in SSPE. This suggests that myoclonus in SSPE may primarily involve the cortex and cortico-subcortical structures such as the thalamus at earlier stages of disease, and then involve more caudal structures as the disease progresses.

Fulminant subacute sclerosing panencephalitis (SSPE) presented with acute hemiparesis in a 13-year-old girl with perinatally acquired HIV infection.

A 13-year-old girl with perinatally acquired HIV infection was admitted to us with acute onset, right-sided hemiparesis of 30 days duration and right-sided myoclonic jerks of 2 days duration affecting the face, upper and lower limbs. On examination, she exhibited increased tone and a pyramidal pattern of weakness in her right upper and lower limbs, along with spontaneous multifocal myoclonic jerks in the affected area. IgG levels in the serum and cerebrospinal fluid for measles were significantly elevated. Brain MRI depicted T2-weighted-hyperintensities in the subcortical white matter. The electroencephalogram demonstrated evidence of lateralised long interval periodic discharges. This patient had no past behavioural problems or poor academic performance. This case underlines the fact that, though subacute sclerosing panencephalitis (SSPE) is a chronic disease, a rare fulminant form of SSPE might develop acutely and atypically, with an increased proclivity for HIV-infected patients.

Atypical Presentation of Fulminating Subacute Sclerosing Panencephalitis: A Case Series.

Subacute sclerosing panencephalitis (SSPE) is a rare and progressive inflammatory disease of central nervous system due to aberrant measles virus with an outcome that is nearly always fatal. In acute fulminant SSPE, the disease rapidly evolves leading to death within 3 months of the diagnosis. We report here four cases of fulminant SSPE with atypical presentations, two of them presented at very early age with history of congenital measles infection in first case and gait abnormality as initial symptom in second case; acute disseminated encephalomyelitis (ADEM) with refractory seizures in third case, unilateral myoclonus with hemiparesis in fourth case at the onset of disease, respectively. The typical periodic electroencephalographic (EEG) complexes, elevated cerebrospinal fluid (CSF), and serum antimeasles antibodies in our patients led to the diagnosis of SSPE. A high index of clinical suspicion in fulminant type with awareness of atypical features, EEG, and CSF studies are of paramount importance in establishing its diagnosis.

The Spectrum of Repetitive Behaviors Associated With Subacute Sclerosing Panencephalitis.

BACKGROUND: Repetitive behaviors refer to a broad class of responses ranging from stereotypic body movements to impulsive/compulsive behaviors. They may be associated with neurological disorders. METHODS: This is a case series of six subacute sclerosing panencephalitis (SSPE) patients who presented with a wide spectrum of repetitive motor behaviors and vocalizations. RESULTS: Repetitive motor behaviors involved the upper limbs in all patients and lower limbs in 3 patients. The repetitive movements in the upper limbs were clapping, finger-clicking, hand rubbing, flailing, and dystonic posturing. In the lower limbs, the repetitive movements were rubbing with the heel, pelvic thrusting with flexion extension of the leg, and foot tapping. The spectrum of vocalizations included palilalia, whistling, grunting with spitting, and pathological crying. Repetitive behaviors were the presenting features in 2 patients. CONCLUSIONS: This case series expands the spectrum of repetitive behaviors seen in neurological disorders associated with brain infections. © 2020 International Parkinson and Movement Disorder Society.

Adult-onset subacute sclerosing panencephalitis presenting with tonic motor seizures.

PURPOSE/AIM OF THE STUDY: Subacute sclerosing panencephalitis (SSPE) is a degenerative disease of the brain caused by a persistent measles virus infection occurring mostly in childhood or early adolescence. The spectrum of epileptic phenomena associated with SSPE is wide, varying from partial or generalized tonic-clonic seizures and atypical absences to myoclonic-atonic attacks. Tonic seizures are very rare in SSPE. MATERIALS AND METHODS: Herein, we discuss a case of 25 years old male that presented with adult-onset SSPE with tonic seizures accompanying myoclonic seizures. RESULTS: Patient was treated with clonazepam 5 mg/day and an isoprinosine regimen with a dose of 70 mg/kg/day. This is the fourth case of SSPE presenting with myoclonic and tonic seizures and the first case of SSPE with myoclonic and tonic seizures reported in an adult-onset case in the English literature. CONCLUSIONS: Adult-onset SSPE with tonic seizures is rare and may be confusing, thus, it is important to recognize the presence of this type of tonic motor seizures in SSPE patients.

Subacute sclerosing panencephalitis: a rare cause of acute cortical visual impairment in an adult.

Adult onset subacute sclerosing panencephalitis (SSPE) after the third decade of life is rare and the manifestations can mimic disorders such as dysmyelinating and metabolic disorders. This case report presents a patient with acute binocular visual impairment in his fifth decade as the first manifestation of SSPE. This is preventable with immunisation against measles. A prior history of measles infection may not be forthcoming in adult onset SSPE. This should be kept in mind as a differential diagnosis when a patient from endemic area presents with acute visual loss even in the absence of classic features. Periodic generalised discharges on the EEG without myoclonus may be seen in this condition rarely as in this case.

Clinical conundrum: status epilepticus culminating into acute dystonia myoclonus.

A 7-year-old child who suffered from symptomatic focal epilepsy as a sequel to perinatal hypoxia used to have frequent seizures. This time she developed prolonged status epilepticus lasting for over 5 hours. She received a treatment in the form of intravenous midazolam and reinitiation of sodium valproate and clobazam that were discontinued previously. Seizures were controlled over a couple of hours, but she remained unresponsive. Later, she developed acute onset dystonia (day 3 post-status epilepticus) and also myoclonic jerks. She presented to us after 3 weeks of onset of these complaints and we considered hypoxic encephalopathy resulting from prolonged status epilepticus or acute encephalitis or non-convulsive status epilepticus. However, acute onset dystonia and periodicity of myoclonic jerks were pointers against it, and on evaluation, she was diagnosed with atypical fulminant subacute sclerosing panencephalitis (SSPE). Knowing the atypical presentations of SSPE is important in planning management and prognostication.