Subacute Sclerosing Panencephalitis Research Articles

Subacute Sclerosing Panencephalitis With Atypical Clinical and MRI Findings

Subacute sclerosing panencephalitis (SSPE) is a progressive inflammatory disorder of the central nervous system and a slow virus infection caused by aberrant measles virus. Typical neurological manifestations include psychomotor impairment, progressive intellectual deterioration, myoclonic jerks and behavioral changes, with or without pyramidal symptoms. It usually affecting people aged 10 to 14 year. We report the case of an 17-year-old girl presenting with initial symptom of visual loss, seizures, a lack of SSPE specific EEG pattern, late onset and atypical fast progression of disease. The case highlights the importance of atypical clinical findings of SSPE at onset and also firstly disappearing, then appearing MRI findings at sequential images which can complicate the accurate diagnosis. High suspicion is needed because of its rareness.

Subakut Sklerozan Panensefalit ve Hemşirelik Bakımı

Subakut sklerozan panensefalit, çocukluk dönemi ve erken adolesan dönemde görülen, santral sinir sisteminin ilerleyici ölümcül bir hastalığıdır. Hastalığın nedeni, mutant kızamık virüsünün sebep olduğu yavaş ilerleyen viral enfeksiyondur. Akut kızamık hastalığının gelişmesi ile subakut sklerozan panensefalitin ilk semptomlarının görülmesi arasındaki kuluçka süresi sıklıkla 4-10 yıl arasındadır. Fakat bu süre bir aydan 27 yıla kadar değişebilmektedir. Hastalığın patogenezi tam olarak bilinmemektedir. Hastalık sürecinde beyinde inflamasyon, nöronal kayıp, gliozis ve demiyelinizasyon oluşmaktadır. Subakut sklerozan panensefalit hastalığının erken klinik karakteristik belirtileri değişiklik göstermesinin yanı sıra bu belirtiler sıklıkla davranışsal değişiklikler, bilişsel bozulma, düşme sporadik atakları ve korioretinit gibi görme bozukluklarını içermektedir. Hastalık ilerlediği zaman; miyoklonik kasılmalar veya spazmlar gibi nörolojik belirtiler daha belirgin hâle gelmekte ve hastada ciddi fiziksel ve zihinsel yetersizlik gelişmektedir. Tanı, karakteristik klinik belirti ve bulguların görülmesi, karakteristik periyodik elektroensefalografi deşarjlarının varlığı ve plazma ile serebrospinal sıvıda kızamık antikor titresinde artışın gösterilmesi ile konulmaktadır. Hastalığın kesin bir tedavisi olmamakla birlikte, oral izoprinozin ve intraventriküler interferonalfa kombinasyonu en etkili tedavi şekli olarak bilinmektedir. Subakut sklerozan panensefalit hastalığı, gelişmekte olan ülkeler için hâlen ciddi bir sağlık sorunudur. Subakut sklerozan panensefalit hastalığı için tek çözüm, etkili kızamık aşısının yapılmasıdır. Subakut sklerozan panensefalit hastalığına karşı korunmada, erken tanılamada, tedavi, bakım ve rehabilitasyonda hemşirelik bakımı büyük önem taşımaktadır.

Interferon alpha in subacute sclerosing panencephalitis: Case report and review of the literature

Subacute Sclerosing Panencephalitis (SSPE) is a rare, rapidly progressive neurodegenerative disease caused by the measles virus. Spontaneous remission and survival longer than 4 years is rare. The disease commonly affects children and adolescents from less privileged socio-economic backgrounds. Prior to immunisation, the incidence of SSPE in South Africa (SA) was 2.6/100 000 people per year, which is higher than the global estimate of 1/1 000 000 per year. The post-immunisation incidence has dropped to 0.43/100 000 people per year. Currently, there is no curative treatment for SSPE. In developed countries, patients have been treated with antiviral therapy and interferon alpha (IFNα) with promising results. There have been no reported studies of children with SSPE treated with IFNα in South Africa. We report on a patient successfully treated with intraventricular INFα.

Amino acid substitutions in the heptad repeat A and C regions of the F protein responsible for neurovirulence of measles virus Osaka-1 strain from a patient with subacute sclerosing panencephalitis

Measles virus (MV) is the causative agent of subacute sclerosing panencephalitis (SSPE). We previously reported that the F gene of the SSPE Osaka-2 strain is the major determinant of MV neurovirulence. Because the sites and extents of mutations differ among SSPE strains, it is necessary to determine the mutations responsible for the SSPE-specific phenotypes of individual viral strain. In this study, recombinant viruses containing the envelope-associated genes from the SSPE Osaka-1 strain were generated in the IC323 wild-type MV background. Hamsters inoculated with MV containing the H gene of the Osaka-1 strain displayed hyperactivity and seizures, but usually recovered and survived. Hamsters inoculated with MV containing the F gene of the Osaka-1 strain displayed severe neurologic signs and died. Amino acid substitutions in the heptad repeat A and C regions of the F protein, including a methionine-to-valine substitution at amino acid 94, play major roles in neurovirulence.

A Multinational Survey on Actual Diagnostics and Treatment of Subacute Sclerosing Panencephalitis

Subacute sclerosing panencephalitis (SSPE) is a chronic infection of the central nervous system caused by the measles virus (MV). Its prevalence remains high in resource poor countries and is likely to increase in the Northern Europe as vaccination rates decrease. Clinical knowledge of this devastating condition, however, is limited. We therefore conducted this multinational survey summarizing experience obtained from more than 500 patients treated by 24 physicians in seven countries. SSPE should be considered in all patients presenting with otherwise unexplained acquired neurological symptoms. In most patients, the diagnosis will be established by the combination of typical clinical symptoms (characteristic repetitive myoclonic jerks), a strong intrathecal synthesis of antibodies to MV and typical electroencephalogram findings (Radermecker complexes). Whereas the therapeutic use of different antiviral (amantadine, ribavirin) and immunomodulatory drugs (isoprinosine, interferons) and of immunoglobulins has been reported repeatedly, optimum application regimen of these drugs has not been established. This is partly due to the absence of common diagnostic and clinical standards focusing on neurological and psychosocial aspects. Carbamazepine, levetiracetam, and clobazam are the drugs most frequently used to control myoclonic jerks. We have established a consensus on essential laboratory and clinical parameters that should facilitate collaborative studies. Those are urgently needed to improve outcome.

Atypical Presentation of Sub Acutesclerosing Pan Encephalitis With Short Onset Latency

The most severe sequel of measles virus infection is sub acutesclerosing pan encephalitis (SSPE), a fatal disease of the central nervous system that generally develops 7–10 years after infection. A 7 ½ year old boy presented with gradual difficulty in walking and speech along with jerky movements of right upper limb which progressed to become generalized and progressive loss of cognition was also observed within days of onset of symptoms. Diagnosis of SSPE was made on the basis of burst suppression pattern on EEG and anti measles antibody in CSF. A differential diagnosis of SSPE should be considered in all forms of acute encephalopathy for early diagnosis and treatment.J Nepal Paediatr Soc 2015;35(1):62-63

The phosphoprotein genes of measles viruses from subacute sclerosing panencephalitis cases encode functional as well as non-functional proteins and display reduced editing

Products expressed from the second (P/V/C) gene are important in replication and abrogating innate immune responses during acute measles virus (MV) infection. Thirteen clone sets were derived from the P/V/C genes of measles virus (MV) RNA extracted from brains of a unique collection of seven cases of subacute sclerosing panencephalitis (SSPE) caused by persistent MV in the central nervous system (CNS). Whether these functions are fully maintained when MV replicates in the CNS has not been previously determined. Co-transcriptional editing of the P mRNAs by non-template insertion of guanine (G) nucleotides, which generates mRNAs encoding the viral V protein, occurs much less frequently (9%) in the SSPE derived samples than during the acute infection (30–50%). Thus it is likely that less V protein, which is involved in combatting the innate immune response, is produced. The P genes in MV from SSPE cases were not altered by biased hypermutation but exhibited a high degree of variation within each case. Most but not all SSPE derived phospho-(P) proteins were functional in mini genome replication/transcription assays. An eight amino acid truncation of the carboxyl-terminus made the P protein non-functional while the insertion of an additional glycine residue by insertion of G nucleotides at the editing site had no effect on protein function.

Subacute sclerosing panencephalitis in South African children following the measles outbreak between 2009 and 2011.

Between 2009 and 2011, there was an outbreak of measles throughout South Africa (SA). The largest age category infected was children<5 years of age. In 2014, four patients, with a median age of 4 years and 5 months (range 4 years 3 months-4.5 years), three males and one female, presented with subacute sclerosing panencephalitis (SSPE). All were infected with measles during the period of the 2009-2011 outbreak in early infancy, at a time when their immune systems were immature and before they were vaccinated against the measles virus. One patient was immunocompromised, with vertically acquired HIV infection. All the children presented with cognitive and behavioural decline, abnormal movements and medically intractable myoclonic and atonic seizures. Outcome was poor in all and no reversibility was evident with standard therapeutic interventions. Optimal seizure control with carbamazepine is reported in patients with SSPE. Three of our patients who received carbamazepine experienced improved seizure control, but their neuroregression continued. Since submission of this case series, patient 1 (see Table 1) has died, and a further child has presented with the same clinical phenotype as described. On the basis of this clustering of patients in the Western Cape Province, SA, it is important to screen children admitted with acute cognitive decline and intractable seizures for SSPE, especially those who were infants during the measles outbreak.

Epilepsi Tanısıyla Takipli Subakut Sklerozan Panensefalitli Olgu

Epilepsi Tanısıyla Takipli Subakut Sklerozan Panensefalitli Olgu

A Comprehensive Comparison of the IEFPCM and SS(V)PE Continuum Solvation Methods with the COSMO Approach.

Dielectric continuum models are popular for modeling solvent effects in quantum chemical calculations. The polarizable continuum model (PCM) was originally published exploiting the exact dielectric boundary condition. This is nowadays called DPCM. The conductor-like screening model (COSMO) introduced a simplified and slightly empirical scaled conductor boundary condition, which turned out to reduce the errors resulting from outlying charge. This was implemented in PCM as CPCM. Later, the integral equation formalism (IEFPCM) and the formally identical SS(V)PE model of Chipman introduced a modified dielectric boundary condition combining the dielectric exactness of DPCM with the reduced outlying charge sensitivity of COSMO. In this paper, we demonstrate on two huge data sets of neutral and ionic solutes that no significant difference can be observed between the COSMO and IEFPCM, if the correct scaling factor is chosen for COSMO.

Progressive subacute sclerosing panencephalitis: A study of two cases with epileptic spasms

Myoclonus has been described as the most frequent type of seizures associated with progressive subacute sclerosing panencephalitis (SSPE). We report two patients who developed SSPE. All patients had a history of measles. The children presented with repetitive episodes of head and trunk drops with frequent falls. Polygraphic electroencephalography (EEG) recording showed electroclinical features compatible with epileptic spasms. The periodic complexes remained unchanged during sleep without concomitant epileptic spasms. The epileptic spasms had a relatively good response to vigabatrin. EEG, cerebrospinal fluid studies, and cerebral magnetic resonance imaging confirmed the diagnosis. Epileptic spasms are probably more frequently associated with SSPE than the literature mentions. Polygraphic-EEG recording is crucial to define the electroclinical features in these patients. The recognition of the types of seizures in SSPE does not only allow for adequate treatment, but also defines the clinical features of this severe and progressive encephalopathy.

The spectrum of MRI findings in subacute sclerosing panencephalitis with clinical and EEG correlates

Reports of magnetic resonance imaging (MRI) findings in subacute sclerosing panencephalitis (SSPE) with clinical and electroencephalography (EEG) correlation are few. To describe the MRI features of SSPE and correlate with its clinical features and EEG. Clinical, MRI and EEG data of 33 patients (male/female 19/14; age: 11.4 ± 5.3 yr) were reviewed. All patients had raised IgG anti-measles antibody (≥ 1:625) in cerebrospinal fluid. Their clinical features were myoclonus (100%), seizures (42%), visual disturbances (18%), pyramidal signs (30%), extrapyramidal symptoms (27%), and cognitive impairment (79%) and behavioral changes (21%). EEGs were universally abnormal: diffuse slowing of background activity-all; periodic complexes-27 (symmetrical): High voltage delta waves (55%) and sharp & slow wave discharges (45%). MRI findings included – normal (9%), cerebral atrophy (78%), white matter (76%) and basal ganglia (6%) changes. Restricted diffusion in periventricular/subcortical region was noted in 4/23 patients (stage 2). Magnetic resonance spectroscopy showed decreased N-acetyl aspartate peaks and elevated choline peaks in 75% and lactate peak in 25% (stage 3) of patients. Correlation of background delta activity among patients with MRI signal abnormalities and those without any signal change was noted (P=0.02). There was significant correlation between visual deficits and bilateral parieto-occipital white matter signal changes (P=0.03). There was no other EEG-MRI or clinical-MRI correlation. MRI abnormalities in SSPE are diverse and may or may not reflect underlying pathology. Visual deficits were observed in patients with parieto-occipital white matter signal change. Restricted diffusion of signal abnormalities and lactate peak in magnetic resonance spectroscopy were uncommon and it may add to better understanding.

Nonconvulsive status epilepticus and decreased frontal glucose metabolism in a case with SSPE

We report a 9-year-old boy with atypical presentation of subacute sclerosing panencephalitis (SSPE). He was admitted due to staring spells and cognitive deterioration. Electroencephalography (EEG) demonstrated bilaterally symmetrical, synchronous, frontal sharp-and-slow wave discharges in 80% of the record. Diazepam or midazolam administration during EEG recording attenuated the sharp-and-wave discharges, but revealed no periodic complexes. Magnetic resonance imaging delineated bilateral frontal T2-weighted hyperintense foci. Fluorodeoxyglucose-positron emission tomography imaging indicated bilaterally decreased glucose metabolism in frontal cortex. The other laboratory tests including measles antibody in cerebrospinal fluid and serum suggested no specific etiology. Interestingly, a month later, the previously detected sharp-and-slow wave discharges disappeared, and periodic slow-wave paroxysms appeared on EEG recording. Measles antibody titers showed seroconversion and confirmed the diagnosis of SSPE. The present case suggests that clinicians be cautious while excluding SSPE.

Some aspects about the clinical and pathogenetic characteristics of the presumed persistent measles infections: SSPE and MINE

It is well known that Subacute Sclerosing PanEncephalitis (SSPE) is due to an aborted form of the wild measles virus which results from a faulty immune reaction of the human body (1). The pathogenesis of this particular slow virus disease begins when an immunologically incompetent individual is attacked by the virus and is thereby unable to launch a full immune response, allowing parts of the aborted virus to harbor in the central nervous system. As is typical of all slow virus diseases, the aborted virus remains quiescent for a number of months to years only to break out to produce the neurological and ophthalmic symptoms of SSPE. The major components of the disease results from the progressive deterioration of the host’s nervous system, first starting with sometimes subtle and nonspecific higher cortical symptoms such as abnormal behavior, learning disabilities, single epileptic seizures and visual disturbances which formulate in months into a characteristic clinical period called stage I. Then the near diagnostic period of repetitive massive myoclonic jerks, beginning mental failure, motor disability in its early stages and immobility are seen which constitutes what has been called stage II. This stage is also progressive and in a few months the involuntary movements disappear and the dementia worsens. Stage III is a nonambulatory state of clinical affairs with ultimately complete motor failure, loss of the previously seen involuntary movements and severe dementia. Stage IV represents a severe “vegetative” stage which plateaus to severe neurological disability of at least 90% or death. This typical clinical progression is closely correlated with a rostral-caudal neural destruction. Most of what is thought to be clinically typical about this disease, is a manifestation of the neuropathological and clinical happenings which occur in stage II. This stage represents the classical subacute progressive clinical picture of what I call the subacute progressive form (SPF) of SSPE. There are other more atypical forms of the disease. The classical or SPF form and presentation represents only about 75% of the cases of SSPE which has been reported to the USA/World SSPE Registry since 1989. In the 1960s, in the heyday of SSPE and natural

A study of SSPE: early clinical features

Thirty two patients with subacute sclerosing panencephalitis (SSPE) admitted under the care of Department of Neurology at JJ Hospital and Grant Medical College, Mumbai during the period 1998-2003 were analyzed. All patients were evaluated clinically, with relevant investigations and neuroimaging wherever possible. Particular attention was given to early clinical features. Diagnosis was confirmed by cerebrospinal fluid study for measles antibody and by electroencephalography. The mean age of our patients was 13.4 years and the vaccinated patients tended to be older. Nine patients had received measles vaccination. Twelve percent of patients were older than the age of 20 years at the onset of symptoms. Approximately 40.6% of patients presented with symptoms of loss of vision, seizures and behavioral change. At this stage myoclonus and cognitive decline were conspicuous by their absence. Eventually typical features like myoclonus and cognitive decline evolved after a mean period of 8 months. Even in the present era, SSPE continues to remain the most important cause of progressive myoclonic epilepsy. With progressive increase in age of presentation, in patients with features like loss of vision, seizures and behavioral changes, SSPE should be carefully considered. (J Pediatr Neurol 2004; 2(2): 73–77).

SLAM- and nectin-4-independent noncytolytic spread of canine distemper virus in astrocytes.

Measles and canine distemper viruses (MeV and CDV, respectively) first replicate in lymphatic and epithelial tissues by using SLAM and nectin-4 as entry receptors, respectively. The viruses may also invade the brain to establish persistent infections, triggering fatal complications, such as subacute sclerosis pan-encephalitis (SSPE) in MeV infection or chronic, multiple sclerosis-like, multifocal demyelinating lesions in the case of CDV infection. In both diseases, persistence is mediated by viral nucleocapsids that do not require packaging into particles for infectivity but are directly transmitted from cell to cell (neurons in SSPE or astrocytes in distemper encephalitis), presumably by relying on restricted microfusion events. Indeed, although morphological evidence of fusion remained undetectable, viral fusion machineries and, thus, a putative cellular receptor, were shown to contribute to persistent infections. Here, we first showed that nectin-4-dependent cell-cell fusion in Vero cells, triggered by a demyelinating CDV strain, remained extremely limited, thereby supporting a potential role of nectin-4 in mediating persistent infections in astrocytes. However, nectin-4 could not be detected in either primary cultured astrocytes or the white matter of tissue sections. In addition, a bioengineered "nectin-4-blind" recombinant CDV retained full cell-to-cell transmission efficacy in primary astrocytes. Combined with our previous report demonstrating the absence of SLAM expression in astrocytes, these findings are suggestive for the existence of a hitherto unrecognized third CDV receptor expressed by glial cells that contributes to the induction of noncytolytic cell-to-cell viral transmission in astrocytes. While persistent measles virus (MeV) infection induces SSPE in humans, persistent canine distemper virus (CDV) infection causes chronic progressive or relapsing demyelination in carnivores. Common to both central nervous system (CNS) infections is that persistence is based on noncytolytic cell-to-cell spread, which, in the case of CDV, was demonstrated to rely on functional membrane fusion machinery complexes. This inferred a mechanism where nucleocapsids are transmitted through macroscopically invisible microfusion events between infected and target cells. Here, we provide evidence that CDV induces such microfusions in a SLAM- and nectin-4-independent manner, thereby strongly suggesting the existence of a third receptor expressed in glial cells (referred to as GliaR). We propose that GliaR governs intercellular transfer of nucleocapsids and hence contributes to viral persistence in the brain and ensuing demyelinating lesions.

Subacute sclerosing panencephalitis presenting with hypersexual behavior.

Sir, Subacute sclerosing panencephalitis (SSPE) is a rare progressive demyelinating disease of the central nervous system associated with a chronic infection of brain tissue with measles virus. The disease is commonly seen in children and young adults. It is characterized by progressive intellectual deterioration, focal and/or generalized seizures, myoclonus, ataxia, and visual disturbances.[1] The presentation varies according to the age of the patient, and the diagnosis is often delayed in adults due to the atypical presentation. The hypersexual disorder is classically defined in persons aged above 18 years and is characterized by the recurrent and intense sexual urge irrespective of the situation persisting beyond 6 months.[2] The disease is usually associated with significant psychiatric ailments and also with central nervous disorders such as stroke, brain injury, and medications. SSPE presenting with hypersexual behavior is uncommon and is rarely reported in the literature. We retrospectively reviewed the data pertaining to four patients of SSPE treated at our hospital between 2012 and 2014. The diagnosis of SSPE is based on the Dyken's criteria.[3] SSPE is diagnosed, if the patient meets any three of the following five criteria: (a) Progressive intellectual deterioration with signs of myoclonus; (b) characteristic electroencephalographic (EEG) pattern; (c) elevated cerebrospinal fluid (CSF) globulin levels; (d) elevated CSF measles antibody titers; and (e) brain biopsy suggestive of measles. The demographic profile and investigation findings of all the patients are summarized in the Table 1.Table 1: Clinical details of all the four patientsBriefly, all our patients are young adults of both sexes and hail from poor socioeconomic strata of the society. All the patients presented with classical behavioral abnormalities, scholastic regression, and a couple of them presented with the hypersexual syndrome. All the patients showed a characteristic EEG pattern of periodic lateralized epileptiform discharge sequences neuroimaging revealed nonspecific white matter hyperintensities in few patients. The paired serum and CSF samples for measles ELISA IgG were positive in all the patients confirming the diagnosis of SSPE. The patients were treated with intrathecal interferon, Isoprinosine, and antipsychotic drugs including risperidone. Sodium valproate was used to control the myoclonus and seizure activity. One patient had a persistent worsening illness with recurrent seizures and succumbed to his illness at the end of 1-year of observation. Behavioral abnormalities improved in the remaining three patients, and they are under regular follow-up. In India, SSPE is still a common neurodegenerative disorder despite an increase in the measles vaccination. The diagnosis and treatment are usually delayed due to the varying presentation of the disease. Our data revealed that three patients were receiving psychiatric treatment for more than a year prior to the proper diagnosis. Poor scholastic performance and cognitive regression are important clues to the underlying diagnosis of SSPE and EEG is often diagnostic in these cases.[4] The clinical presentation of adult onset differs from childhood onset as, personality changes and ophthalmic manifestations are common presenting features and survival with treatment have been better in certain series.[5] Our data had patients from the second and third decades of life, and none of the patients had ophthalmic manifestations. Hypersexual behavior leads to social stigma and is often underreported by the patients. The same has been linked with a variety of neuropsychiatric disorders including obsessive-compulsive disorder, bipolar disorder, drugs such as dopaminergic agonists and other disorders including stroke and brain injury. The prevalence of SSPE is common among lower socioeconomic strata, large family size, and rural areas due to overcrowding. The measles virus is transmitted by respiratory secretions via aerosol exposure and also through direct contact with larger droplets.[1] A variety of metabolic disorders leads to dementia in young including Wilson's disease, hypothyroidism, B12 deficiency, etc. Our patients were investigated for these conditions and the negative screen resulted in the psychiatric diagnosis. It is essential for all the practitioners to look for myoclonus and also investigate for the rare causes of dementia such as SSPE and prion diseases. The therapy of SSPE involves the use of isoprinosine and an immunomodulator like interferon. The response to therapy depends on the clinical stage of SSPE at which the treatment was started. SSPE staging is done as per the modified Jabbour's classification and patients with stage 1 disease respond remarkably to the therapy whereas, stage 2 disease progresses invariably resulting in fatal outcomes in 2–5 years. To conclude, SSPE is a devastating disorder of public health importance in the developing countries. A high index of suspicion for SSPE is required during the evaluation of young adults with myoclonus, behavioral changes, and scholastic regression. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

Measles Virus: Identification in the M Protein Primary Sequence of a Potential Molecular Marker for Subacute Sclerosing Panencephalitis

Subacute Sclerosing Panencephalitis (SSPE), a rare lethal disease of children and young adults due to persistence of measles virus (MeV) in the brain, is caused by wild type (wt) MeV. Why MeV vaccine strains never cause SSPE is completely unknown. Hypothesizing that this phenotypic difference could potentially be represented by a molecular marker, we compared glycoprotein and matrix (M) genes from SSPE cases with those from the Moraten vaccine strain, searching for differential structural motifs. We observed that all known SSPE viruses have residues P64, E89, and A209 (PEA) in their M proteins whereas the equivalent residues for vaccine strains are either S64, K89, and T209 (SKT) as in Moraten or PKT. Through the construction of MeV recombinants, we have obtained evidence that the wt MeV-M protein PEA motif, in particular A209, is linked to increased viral spread. Importantly, for the 10 wt genotypes (of 23) that have had their M proteins sequenced, 9 have the PEA motif, the exception being B3, which has PET. Interestingly, cases of SSPE caused by genotype B3 have yet to be reported. In conclusion, our results strongly suggest that the PEA motif is a molecular marker for wt MeV at risk to cause SSPE.

Subacute sclerosing panencephalitis in a child with recurrent febrile seizures.

Subacute sclerosing panencephalitis (SSPE) is a devastating disease of the central nervous system (CNS) caused by persistent mutant measles virus infection. The diagnosis of SSPE is based on characteristic clinical and EEG findings and demonstration of elevated antibody titres against measles in cerebrospinal fluid. Subacute sclerosing panencephalitis can have atypical clinical features at the onset. Herein, we report an unusual case of subacute sclerosing panencephalitis in a child with recurrent febrile seizures. The disease progressed with an appearance of myoclonic jerks, periodic high amplitude generalized complexes on EEG, and elevated titers of measles antibodies in cerebrospinal fluid leading to the final diagnosis of subacute sclerosing panencephalitis.

A decrease of regulatory T cells and altered expression of NK receptors are observed in subacute sclerosing panencephalitis.

Subacute sclerosing panencephalitis (SSPE) is caused by a persistent measles virus infection. Regulatory mechanisms can be responsible for a failure of immunosurveillance in children with SSPE. In this study, peripheral blood cells of 71 patients with SSPE and 57 children with other diseases were compared phenotypically. The proportions of CD4(+), CD8(+) T, and NK cells were homogenous, whereas total CD3(+) T and Treg (CD4(+)CD25(+)CD152(+)) cells were decreased in patients with SSPE. The proportion of CD8(+) T cells expressing the inhibitory NKG2A(+) receptor was also decreased (1.7% ± 1.7% vs. 2.6% ± 1.9%, p = 0.007) in patients with SSPE, whereas the proportion of NK cells expressing activating NKG2C was increased compared with the control group (30.0% ± 17.3% vs. 22.2% ± 17.0%, p = 0.039). The decrease in the number of cells with regulatory phenotype, the lower presence of the inhibitory NK receptors on CD8(+) cells, and higher activating NK receptors on NK cells in SSPE indicate an upregulation of these cell types that favors their response. This state of active immune response may be caused by chronic stimulation of viral antigens leading to altered regulatory pathways.