RESUMEN
Subacute sclerosing panencephalitis (SSPE) is a fatal disorder that occurs as a rare complication of childhood measles. Symptoms typically manifest between the ages of 5 and 15. While the incidence of SSPE is declining globally, it is still prevalent in regions where measles remains common and vaccination rates are low due to poverty and lack of health education. Diagnosing SSPE can be challenging, particularly when patients exhibit unusual symptoms. A thorough clinical evaluation, including vaccination history, physical examination, electroencephalogram (EEG) and Cerebrospinal fluid (CSF) analysis, can help in making a diagnosis. We present the case of a young woman in her early 20s who initially experienced depressive symptoms, followed by myoclonus, dementia and visual impairment. The patient was ultimately diagnosed with SSPE based on characteristic EEG findings, neuroimaging results, CSF analysis and elevated serum measles antibody levels.
Asunto(s)
Electroencefalografía , Panencefalitis Esclerosante Subaguda , Humanos , Panencefalitis Esclerosante Subaguda/diagnóstico , Panencefalitis Esclerosante Subaguda/complicaciones , Femenino , Depresión/etiología , Depresión/diagnóstico , Diagnóstico Diferencial , Adulto Joven , Sarampión/complicaciones , Sarampión/diagnóstico , Adulto , Mioclonía/etiología , Mioclonía/diagnósticoRESUMEN
BACKGROUND: Subacute sclerosing panencephalitis (SSPE) is a complication of measles, occurring after a latency of 4-10 years. It continues to occur in developing countries although resurgence is being reported from developed countries. Characteristic features include progressive neuropsychiatric issues, myoclonus, seizures, movement disorders and visual impairment. Electroencephalography (EEG) typically shows periodic generalized discharges, and elevated CSF anti-measles antibodies are diagnostic. Movement disorders are being increasingly recognized as part of the clinical spectrum, and range from hyperkinetic (chorea, dystonia, tremor, tics) to hypokinetic (parkinsonism) disorders and ataxia. OBJECTIVES: This article aims to comprehensively review the spectrum of movement disorders associated with SSPE. METHODS: A literature search was conducted in PubMed and EMBASE databases in December 2023 and articles were identified for review. RESULTS: Movement disorders reported in SSPE included hyperkinetic (chorea, dystonia, tremor and tics), hypokinetic (parkinsonism), ataxia and extraocular movement disorders. Myoclonus, a core clinical feature, was the most frequent "abnormal movement." Movement disorders were observed in all clinical stages, and could also be a presenting feature, even sans myoclonus. Hyperkinetic movement disorders were more common than hypokinetic movement disorders. An evolution of movement disorders was observed, with ataxia, chorea and dystonia occurring earlier, and parkinsonism later in the disease. Neuroradiological correlates of movement disorders remained unclear. CONCLUSION: A wide spectrum of movement disorders was observed throughout the clinical stages of SSPE. Most data were derived from case reports and small case series. Multicentric longitudinal studies are required to better delineate the spectrum and evolution of movement disorders in SSPE.
Asunto(s)
Trastornos del Movimiento , Panencefalitis Esclerosante Subaguda , Humanos , Corea/etiología , Corea/fisiopatología , Corea/diagnóstico , Distonía/etiología , Distonía/fisiopatología , Electroencefalografía , Trastornos del Movimiento/etiología , Trastornos del Movimiento/fisiopatología , Trastornos del Movimiento/diagnóstico , Mioclonía/etiología , Mioclonía/fisiopatología , Panencefalitis Esclerosante Subaguda/complicaciones , Panencefalitis Esclerosante Subaguda/diagnóstico , Panencefalitis Esclerosante Subaguda/fisiopatología , Temblor/etiologíaAsunto(s)
Panencefalitis Esclerosante Subaguda , Tortícolis , Humanos , Tortícolis/etiología , Tortícolis/fisiopatología , Panencefalitis Esclerosante Subaguda/complicaciones , Panencefalitis Esclerosante Subaguda/diagnóstico , Panencefalitis Esclerosante Subaguda/fisiopatología , Masculino , Femenino , AdultoRESUMEN
Subacute sclerosing panencephalitis (SSPE) is an irreversible and progressive neurological disorder. A 20-year-old woman with SSPE presented with a decline in visual acuity. Anterior segment was evaluated with slit lamp and in vivo confocal microscopy, revealing the presence of dendritiform keratic precipitates and +2 cells in the anterior chamber. In fundus examination, white-yellowish lesions involving the macula and periphery were observed, which gradually progressed into atrophy over time. Optical coherence tomography (OCT) imaging showed progression to atrophy of moth-eaten shaped cavities including all retinal layers due to necrotizing retinitis. OCT angiography (OCTA) further revealed reduced vessel densities and flow void areas. Notably, to the best of our knowledge, this is the first case documenting anterior segment findings in SSPE in detail. [Ophthalmic Surg Lasers Imaging Retina 2024;55:344-348.].
Asunto(s)
Imagen Multimodal , Panencefalitis Esclerosante Subaguda , Tomografía de Coherencia Óptica , Humanos , Femenino , Panencefalitis Esclerosante Subaguda/diagnóstico , Tomografía de Coherencia Óptica/métodos , Adulto Joven , Segmento Anterior del Ojo/diagnóstico por imagen , Angiografía con Fluoresceína/métodos , Agudeza Visual , Microscopía Confocal/métodos , Fondo de OjoRESUMEN
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.
Asunto(s)
Distonía , Trastornos Distónicos , Panencefalitis Esclerosante Subaguda , Niño , Humanos , Panencefalitis Esclerosante Subaguda/complicaciones , Panencefalitis Esclerosante Subaguda/diagnóstico , Distonía/etiología , Virus del Sarampión , Imagen por Resonancia Magnética , ElectroencefalografíaRESUMEN
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.
Asunto(s)
Sarampión , Enfermedades Neurodegenerativas , Panencefalitis Esclerosante Subaguda , Humanos , Masculino , Niño , Panencefalitis Esclerosante Subaguda/diagnóstico , Panencefalitis Esclerosante Subaguda/complicaciones , Panencefalitis Esclerosante Subaguda/epidemiología , Enfermedades Neurodegenerativas/complicaciones , Sarampión/complicaciones , Sarampión/diagnóstico , Convulsiones/complicaciones , Imagen por Resonancia MagnéticaRESUMEN
Vision loss is a presenting complaint in many patients with subacute sclerosing panencephalitis (SSPE). Data related to vision loss in SSPE is available only in the form of case reports. In this systematic review, we evaluated characteristics of vision loss, affected anatomic site, and patient course and outcome. We extracted data from four databases: PubMed, Embase, Scopus, and Google Scholar. The last search was done on October 26, 2022. We adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The protocol was registered with PROSPERO (CRD42022362652). Dyken's criteria were used for the diagnosis of SSPE. The data were recorded in an Excel sheet. The Joanna Briggs Institute Critical Appraisal tool was used to assess the quality of data. The mean age of patients with SSPE was 17.9 years. Males outnumbered females (60:34). In 73 patients (76%), duration of illness/onset of vision loss was less than 6 months. In 76% patients (n = 73), visual manifestations appeared before encephalopathy. Involvement of the retina (58 of 96, 60.4%), optic nerve (9 of 96, 9.3%), or cerebral cortex (29 of 96, 30.2%) was responsible for vision loss. T2/fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI) parieto-occipital hyperintensities were the most frequent (71.4%) neuroimaging abnormality. Retinal biopsy revealed similar findings revealed by brain histopathology. All patients died and became akinetic mute during the follow-up period, which ranged from a few weeks to a few years. In conclusion, retinal involvement was the most common cause of vision loss. Vision loss often precedes encephalopathy. Cortical vision loss was associated invariably with T2/FLAIR MRI hyperintensities in the parieto-occipital region.
Asunto(s)
Panencefalitis Esclerosante Subaguda , Masculino , Femenino , Humanos , Adolescente , Panencefalitis Esclerosante Subaguda/diagnóstico , Panencefalitis Esclerosante Subaguda/diagnóstico por imagen , Encéfalo/patología , Trastornos de la Visión/etiología , Imagen por Resonancia Magnética , NeuroimagenRESUMEN
Homozygous mutations in the triggering receptor expressed on myeloid cells 2 (TREM2) gene are known to cause Nasu-Hakola disease, which is a rare cause of progressive presenile dementia. A 36-year-old woman presented with repetitive seizures, a 5-year history of progressive behavioral and cognitive changes, and an affected sibling. Magnetic resonance imaging of the brain revealed an ischemic lesion in the left medial temporal lobe. Extensive evaluation of juvenile stroke revealed that viral and autoimmune encephalitides, serum lactate and pyruvate levels, and cerebrospinal fluid composition were all normal. Brain magnetic resonance imaging was notable of thinning of the corpus callosum and caudate and frontotemporal cortical atrophy, in addition to the ischemic lesion. Whole exome sequencing revealed a homozygous mutation (c.A257T; p.D86V) in TREM2. The present case expands the clinical phenotype of Nasu-Hakola disease and further suggests that TREM2 pathway might have role in vessel wall health.
Asunto(s)
Lipodistrofia , Accidente Cerebrovascular , Panencefalitis Esclerosante Subaguda , Humanos , Panencefalitis Esclerosante Subaguda/diagnóstico , Panencefalitis Esclerosante Subaguda/genética , Encéfalo/patología , Lipodistrofia/genética , Accidente Cerebrovascular/genéticaRESUMEN
BACKGROUND: Subacute sclerosing panencephalitis (SSPE) is a devastating brain disease caused by persistent infection by the measles virus. Several cases of SSPE in pregnant ladies have been described. This systematic review is focused on maternal and foetal outcomes among pregnant women with SSPE. METHODS: We searched four databases (PubMed, Embase, Scopus, and Google Scholar). We reviewed all relevant cases, published until 14 August 2022. The review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The protocol was registered with PROSPERO (CRD42022348630). The search items that we used were "((Pregnancy) OR (delivery)) AND (Subacute sclerosing panencephalitis (SSPE))". Dyken's criteria were used for the diagnosis of SSPE in pregnant women. The extracted data was recorded in an Excel sheet. The Joanna Briggs Institute Critical Appraisal tool for case reports was used to assess the quality of published cases. RESULTS: We came across 19 reports describing details of 21 cases. The age of SSPE-affected women varied from 14 to 34 years (mean 23 years). In the majority (n=14), clinical manifestations were started in the antepartum period. Nine pregnant SSPE women presented with vision loss. After delivery, 13 SSPE-affected women died. On the contrary, 15 foetuses, though the majority were preterm, were alive. Five foetuses either died soon after birth or were still-born. CONCLUSION: In conclusion, SSPE in pregnancy is often missed, as it mimics eclampsia. SSPE in pregnancy usually has a devastating course. Universal early childhood measles vaccination is the only way to fight this menace.
Asunto(s)
Sarampión , Panencefalitis Esclerosante Subaguda , Recién Nacido , Femenino , Humanos , Preescolar , Embarazo , Adolescente , Adulto Joven , Adulto , Panencefalitis Esclerosante Subaguda/diagnóstico , Panencefalitis Esclerosante Subaguda/etiología , Mujeres Embarazadas , Virus del Sarampión , Trastornos de la Visión , Familia , Sarampión/complicacionesRESUMEN
Purpose: To report ocular findings in a case of atypical fulminant SSPECase report: A 20-year-old male who came with macular necrotising retinitis in both his eyes in absence of any neurological feature. Within a week the patient developed dystonic posturing and seizures. CSF examination revealed raised measles antibody titres and EEG was suggestive of SSPE. The patient succumbed to the disease within 35 days of presentation.Conclusion: SSPE can rarely have a rapidly progressive downhill course without typical neurological features and ophthalmic features which appear to be more consistent may help in clinching the diagnosis in these cases.
Asunto(s)
Sarampión , Retinitis , Panencefalitis Esclerosante Subaguda , Masculino , Humanos , Adulto Joven , Adulto , Panencefalitis Esclerosante Subaguda/diagnóstico , Sarampión/diagnóstico , Retinitis/diagnóstico , Retinitis/etiología , Ojo , Diagnóstico Diferencial , ElectroencefalografíaRESUMEN
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.
Asunto(s)
Mácula Lútea , Retinitis , Panencefalitis Esclerosante Subaguda , Humanos , Adulto Joven , Adulto , Panencefalitis Esclerosante Subaguda/complicaciones , Panencefalitis Esclerosante Subaguda/diagnóstico , Panencefalitis Esclerosante Subaguda/patología , Tomografía de Coherencia Óptica/métodos , Retinitis/diagnóstico , Retinitis/etiología , Retina/patología , Mácula Lútea/patología , Angiografía con Fluoresceína/métodosRESUMEN
PURPOSE: To describe clinical and imaging findings in a young boy presenting with bilateral rapidly progressive necrotizing macular retinitis. METHODS: A 12-year-old Asian Indian boy developed bilateral progressive macular retinitis. He had generalized tonic-clonic seizures for the past 3 months and gave a history of poor scholastic performance with dementia of recent onset. Multimodal imaging comprising and detailed systemic and laboratory work-up was performed. RESULTS: Both eyes showed rapidly progressive full-thickness retinitis lesions observed as disruption of retinal architecture in both eyes. Left eye optical coherence tomography shows full-thickness retinal involvement with sparing of the internal limiting membrane. Electroencephalogram and magnetic resonance imaging (brain) were suggestive of subacute sclerosing panencephalitis and the diagnosis was confirmed by elevated cerebrospinal fluid and serum IgG measles. The patient did not survive despite treatment with systemic interferon therapy. CONCLUSION: It is important to look for the measles virus as a probable cause of necrotizing retinitis and neurologic symptoms in immunocompetent unvaccinated young patients. Early referral to a neurologist may assist in the early diagnosis of subacute sclerosing panencephalitis and targeted therapy.
Asunto(s)
Retinitis , Panencefalitis Esclerosante Subaguda , Masculino , Humanos , Niño , Panencefalitis Esclerosante Subaguda/diagnóstico , Panencefalitis Esclerosante Subaguda/tratamiento farmacológico , Panencefalitis Esclerosante Subaguda/patología , Retinitis/diagnóstico , Retina/patología , Encéfalo , Imagen por Resonancia MagnéticaRESUMEN
New pediatric and adult subacute sclerosing panencephalitis cases between 1996 and 2020 were reported based on an established UK registry with no evidence of under-ascertainment using a separate pediatric surveillance system. After 15 years with no pediatric UK-acquired cases, 3 cases arose from 2017 after increased measles. Modeling suggested this was in line with measles notifications, underreporting of laboratory-confirmed measles or increased subacute sclerosing panencephalitis risk.
Asunto(s)
Panencefalitis Esclerosante Subaguda , Humanos , Panencefalitis Esclerosante Subaguda/diagnóstico , Panencefalitis Esclerosante Subaguda/epidemiología , Reino Unido/epidemiologíaRESUMEN
BACKGROUND: Subacute Sclerosing Panencephalitis (SSPE) mainly affects children and young people. It is a rare, chronic progressive degenerative form of cerebral inflammation with various infectious noxa, which develops for years after a primary, uncomplicated infection, and the highest percentage can be caused by measles virus and in rare cases by rubella. The aim of the present study is to investigate in the laboratory the role of measles virus in the development of neurological symptoms and diseases of the CNS. METHODS: A total of 46 clinical materials (23 sera samples and 23 CSF) obtained from 23 patients with neurological symptoms and diagnoses: "SSPE" (in 10 patients) and "Encephalitis" (in 13 patients), in the period January 2011 - December 2020 were tested in the National Reference Laboratory (NRL) "Measles, mumps and rubella" at National Centre of Infectious and Parasitic Diseases (NCIPD), Sofia, Bulgaria. Serological (indirect ELISA test for the detection of specific measles IgG/IgM antibodies in serum samples and cerebrospinal fluid) and molecular (RT-PCR for the demonstration of viral RNA) methods were used. RESULTS: The study was performed by parallel testing of serum samples and CSF from each patient. Positive results for measles IgG antibodies in sera were found in 21 patients. Presence of measles IgG antibodies in CSF was demonstrated in four children with diagnosis SSPE (two children at 4 years, one child at 4 years and 6 months, and one at 11 years old). All children with positive laboratory results for SSPE had evidence of MeV infection before 2 years of age. The patients with SSPE had high antibody titers (CSF > 230 U/mL) in their CSF. Patients with positive anti-Measles IgG in the CSF were also found to have positive results for protective measles IgG in the serum samples and their IgG titers were nearly twice as high compared to other patients' sera. The presence of specific measles IgM antibodies was not demonstrated in the tested specimens. RT-PCR test was performed for all samples, and the presence of viral RNA was not detected. CONCLUSIONS: The measles infection can be a reason for developing serious complications affecting CNS in all age groups. SSPE itself is extremely difficult to diagnose, which is why laboratory confirmation of any clinical case is a necessary condition for effective disease surveillance.
Asunto(s)
Rubéola (Sarampión Alemán) , Panencefalitis Esclerosante Subaguda , Adolescente , Anticuerpos Antivirales/análisis , Niño , Humanos , Inmunoglobulina G , Inmunoglobulina M/análisis , Virus del Sarampión/genética , Panencefalitis Esclerosante Subaguda/líquido cefalorraquídeo , Panencefalitis Esclerosante Subaguda/diagnósticoRESUMEN
The oligoclonal band indicates presence of antibodies specific to the disease, possibly due to the activation of certain clones of B lymphocytes. This intrathecal immunoglobin synthesis can be persistent for months to years, for example, in respons to paramyxoviruses, herpes virus, coxsackievirus, and Treponema pallidum; or can be synthesized for life, for example in multiple sclerosis and subacute sclerosing panencephalitis (SSPE). We report a case of SSPE in a 15-year-old male patient. The patient had myoclonic jerks that occurred in the thoracal femoral region. Necessary laboratory tests identified reactive anti-measles IgG, which indicates a previous measles infection or exposure to vaccination. This report describes the usefulness of the oligoclonal bands in the diagnosis of the neurodegenerative disease SSPE that is progressive and fatal to the central nervous system due to persistent measles virus infection in the gray and white matter.
Asunto(s)
Enfermedades Neurodegenerativas , Panencefalitis Esclerosante Subaguda , Adolescente , Anticuerpos Antivirales , Técnicas de Laboratorio Clínico , Humanos , Inmunoglobulina G , Masculino , Virus del Sarampión , Bandas Oligoclonales , Panencefalitis Esclerosante Subaguda/diagnósticoRESUMEN
High measles-specific antibody titers in the cerebrospinal fluid (CSF) have important diagnostic significance for subacute sclerosing panencephalitis (SSPE), a progressive neurological disorder caused by measles virus variants. However, the diagnostic reference value of antibody levels and the usefulness of the CSF/serum ratio measured using enzyme immunoassays (EIAs) for SSPE diagnosis remain unclear. To facilitate SSPE diagnosis using EIAs, measles immunoglobulin G (IgG) titers in the CSF and serum of patients with and without SSPE were measured and their CSF/serum antibody ratios evaluated. Serum and CSF antibody levels were compared among three patients with SSPE (59 paired samples), 37 non-SSPE patients, and 2618 patients of unknown backgrounds. Of the 59 paired samples from three patients with SSPE, 56 paired samples (94.9%) showed CSF measles IgG levels ≥0.5 IU/mL and a CSF/serum ratio ≥0.05, whereas non-SSPE cases showed CSF measles IgG levels <0.1 IU/mL and a CSF/serum ratio <0.03. Of the 2618 CSF samples with unknown backgrounds, 951 showed measurable IgG levels with EIA, with a CSF/serum ratio peak of 0.005-0.02, with a 90th percentile of 0.05. Assuming the SSPE criteria as CSF measles IgG ≥0.5 IU/mL and a CSF/serum ratio ≥0.05, only 20 samples (0.8%) with unknown backgrounds were categorized as having SSPE. Conversely, assuming the non-SSPE criteria as CSF measles IgG <0.1 IU/mL and a CSF/serum ratio <0.03, 2403 samples (92%) with unknown backgrounds were categorized as not having SSPE. In conclusion, high CSF/serum ratios (≥0.05) and high measles CSF IgG levels (≥0.5 IU/mL) may be useful for diagnosing SSPE.
Asunto(s)
Panencefalitis Esclerosante Subaguda , Anticuerpos Antivirales , Humanos , Técnicas para Inmunoenzimas , Inmunoglobulina G , Virus del Sarampión , Valores de Referencia , Panencefalitis Esclerosante Subaguda/líquido cefalorraquídeo , Panencefalitis Esclerosante Subaguda/diagnósticoRESUMEN
Subacute sclerosing panencephalitis, a late complication of measles, is still present during epidemics of this disease due to insufficient vaccination. After a historical review, the importance of the diagnostic criteria and the pathophysiology of SSEP are discussed. Numerous studies on the parameters of innate immunity and interferon responses tend to show a decrease in the activity of cellular immunity. Several hypotheses are formulated based on the publications of the different forms of the disease: Congenital, perinatal, forms with short incubation similar to acute inclusion encephalitis (AIE), rapidly evolving forms, forms of the immunocompromised, or even adults. Familial forms have been identified, suggesting a genetic cause. Based on the duration of the latency period, two groups have been individualized, prompting a retrospective and prospective analysis of the exomes of these patients. The knowledge of the genes involved should be useful for the understanding of the pathophysiology of SSPE and other late neurological RNA virus infections.
Title: La panencéphalite sclérosante subaiguë de la rougeole - Une maladie mortelle encore présente et toujours mystérieuse. Abstract: La panencéphalite sclérosante subaiguë (PESS), une complication tardive de la rougeole, est encore présente lors d'épidémies de cette maladie dues aux insuffisances de la vaccination. Après un rappel historique, nous aborderons la physiopathologie de la PESS et l'importance des critères diagnostiques. De nombreux travaux portant sur les paramètres de l'immunité innée et sur ceux des réponses interféron tendent à montrer une baisse de l'activité de l'immunité cellulaire au cours de cette maladie. Nous formulons ici plusieurs hypothèses s'appuyant sur des publications concernant différentes formes de la maladie : congénitales, périnatales, formes à incubation courte, semblables à l'encéphalite aiguë à inclusions (EAI), formes d'évolution rapide, formes retrouvées chez les immunodéprimés ou chez l'adulte. Des formes familiales ont également été identifiées, suggérant une origine génétique. Selon la durée de la période de latence entre rougeole et la PESS, deux groupes de patients ont été individualisés, incitant à des analyses rétrospective et prospective des exomes de ces malades. La connaissance des gènes participant à la maladie devrait être utile pour la compréhension de la physiopathologie de la PESS mais aussi d'autres infections neurologiques tardives dues à des virus à ARN.