Blindness, dancing extremities, and corpus callosum and brain stem involvement: an unusual presentation of fulminant subacute sclerosing panencephalitis

Movement Disorders in Patients with Subacute Sclerosing Panencephalitis: A Systematic Review

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.

Differential diagnosis of chorea (guidelines of the German Neurological Society)

INTRODUCTION

Choreiform movement disorders are characterized by involuntary, rapid, irregular, and unpredictable movements of the limbs, face, neck, and trunk. These movements often initially go unnoticed by the affected individuals and may blend together with seemingly intended, random motions. Choreiform movements can occur both at rest and during voluntary movements. They typically increase in intensity with stress and physical activity and essentially cease during deep sleep stages. In particularly in advanced stages of Huntington disease (HD), choreiform hyperkinesia occurs alongside with dystonic postures of the limbs or trunk before they typically decrease in intensity. The differential diagnosis of HD can be complex. Here, the authors aim to provide guidance for the diagnostic process. This guidance was prepared for the German Neurological Society (DGN) for German-speaking countries.

RECOMMENDATIONS

Hereditary (inherited) and non-hereditary (non-inherited) forms of chorea can be distinguished. Therefore, the family history is crucial. However, even in conditions with autosomal-dominant transmission such as HD, unremarkable family histories do not necessarily rule out a hereditary form (e.g., in cases of early deceased or unknown parents, uncertainties in familial relationships, as well as in offspring of parents with CAG repeats in the expandable range (27-35 CAG repeats) which may display expansions into the pathogenic range).

CONCLUSIONS

The differential diagnosis of chorea can be challenging. This guidance prepared for the German Neurological Society (DGN) reflects the state of the art as of 2023.

Subacute Sclerosing Panencephalitis in a 63-Year-Old Woman Presenting as Generalized Choreoathetosis

The persistence of measles virus infection in childhood and early adolescence can rarely lead to a fatal progressive neurodegenerative disorder known as subacute sclerosing panencephalitis (SSPE), characterized by behavioral disturbances and intellectual disability followed by myoclonic jerks and occasional negative myoclonus. Movement disorders are rarely presenting manifestations in SSPE. We herein report a 63-year-old woman with generalized choreoathetosis as the presenting manifestation of stage-I SSPE. Our case was atypical for the patient's age and clinical presentation with generalized choreoathetosis and bilateral putaminal and caudate nucleus signal hyperintensity. Though highly uncommon, neurologists should keep SSPE as a differential diagnosis among patients with movement disorders. Measles-endemic countries should be more vigilant to the atypical and rare presentations of SSPE, such as generalized choreoathetosis.

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.

Measles-Associated CNS Complications: A Review

Measles virus infection is a common infectious disease of childhood, incidence of which is still high in developing countries. Other than the morbidity associated with the acute systemic infection, the measles virus can cause serious fatal neural complications. It can either enter the brain leading to acute encephalitis like primary measles encephalitis and acute post infectious measles encephalomyelitis or it may persist in brain cells (as mutated virus) leading to long-term neurodegenerative diseases like measles inclusion body encephalitis and subacute sclerosing pan encephalitis. The patho-clinical features, treatment, and the outcomes of these complications are different and should be identified in time for early diagnosis and management.

Altered white matter integrity in patients with monocular blindness: A diffusion tensor imaging and tract-based spatial statistics study

BACKGROUND

Visual deprivation can lead to abnormal and plastic changes in the brain's visual system and other systems. Although the secondary changes of gray matter in patients have been well studied, the study of white matter is rare. In fact, subtle changes in white matter may be revealed by diffusion tensor imaging, and tract-based spatial statistics can be used to analyze DTI image data.

PURPOSE

In the present study, diffusion tensor imaging (DTI) and tract-based spatial statistics (TBSS) were used to investigate abnormal structural changes in the white matter (WM) of patients with monocular blindness (MB).

METHODS

We recruited 16 healthy controls (HC) (fourteen males and two females) and 16 patients (fifteen males and one female) with right-eye blindness (without differences in left-eye vision). All patients were of similar age. Data acquisition was performed using magnetic resonance imaging (MRI) and DTI. Voxel-based whole brain comparisons of fractional anisotropy (FA) and radial diffusivity (RD) of WM fibers in patients and HC were performed using the TBSS method. The mean FA and RD values for altered brain regions in MB patients were analyzed via the receiver operating characteristic (ROC) curve. Correlation analysis was performed to investigate the relationships between the average FA (RD) value of the whole brain and anxiety score, depression score, and visual function questionnaire score in MB patients.

RESULTS

In MB patients, the mean FA of the whole brain was decreased versus HC. Moreover, the FA values of the corpus callosum, the corona radiata, the posterior thalamic radiation, and the right retrolenticular part of internal capsule were significantly decreased. In addition, the average RD value of the whole brain in MB patients was higher than that observed in HC. The mean FA and RD values of brain regions were analyzed using the ROC curve, and the results showed that the area under the ROC curve was more accurate. Furthermore, the average FA and RD values of the whole brain were significantly correlated with anxiety score, depression score, and visual function-related quality of life score.

CONCLUSION

DTI and TBSS may be useful in examining abnormal spontaneous alterations in the WM of MB patients. The observed changes in FA and RD values may imply the larvaceous neurological mechanism involved in MB.

Subacute sclerosing panencephalitis

Subacute sclerosing panencephalitis (SSPE) is a slowly progressive brain disorder caused by mutant measles virus. SSPE affects younger age groups. SSPE incidence is proportional to that of measles. High-income countries have seen substantial decline in SSPE incidence following universal vaccination against measles. SSPE virus differs from wild measles virus. Measles virus genome recovered from the autopsied brain tissues demonstrates clustered mutations in virus genome particularly in the M gene. These mutations destroy the structure and functioning of the encoded proteins. Complete infectious virus particle has rarely been recovered from the brain. Human neurons lack required receptor for entry of measles virus inside the neurons. Recent in vitro studies suggest that mutations in F protein confer hyperfusogenic properties to measles virus facilitating transneuronal viral spread. The inflammatory response in the brain leads to extensive tissue damage. Clinically, SSPE is characterized by florid panencephalitis. Clinically, SSPE is characterized by cognitive decline, periodic myoclonus, gait abnormalities, vision loss, and ultimately to a vegetative state. Chorioretinitis is a common ocular abnormality. Electroencephalography (EEG) shows characteristic periodic discharges. Neuroimaging demonstrates periventricular white matter signal abnormalities. In advanced stages, there is marked cerebral atrophy. Definitive diagnosis requires demonstration of elevated measles antibody titers in cerebrospinal fluid (CSF). Many drugs have been used to stabilize the course of the disease but without evidence from randomized clinical trials. Six percent of patients may experience prolonged spontaneous remission. Fusion inhibitor peptide may, in the future, be exploited to treat SSPE. A universal vaccination against measles is the only proven way to tackle this menace currently.

Subacute Sclerosing Panencephalitis Presenting as Choreoathetosis and Basal Ganglia Hyperintensities

Subacute sclerosing panencephalitis is a devastating neurodegenerative disorder characterized by cognitive and memory deterioration, personality changes, behavior abnormalities, and a steady motor decline. Extrapyramidal manifestations are commonly seen in the advanced stage of the disease. We discuss a 10-year-old boy with subacute sclerosing panencephalitis presenting with generalized choreoathetosis, myoclonus, and cognitive decline. He had not been immunized for measles. His elder sister had a viral exanthematous illness 4 years ago. Magnetic resonance imaging revealed bilateral, asymmetric putaminal hyperintensities. A diagnosis of subacute sclerosing panencephalitis was confirmed by periodic complexes in the electroencephalograph and elevated antimeasles antibody titers in the blood and cerebrospinal fluid (1:625). Our case highlights that atypical clinical and radiological features of subacute sclerosing panencephalitis should always be borne in mind in children from endemic areas. Generalized choreoathetosis and bilateral putaminal involvement in the index case add to the spectrum of atypical presentations of subacute sclerosing panencephalitis in children.

Subacute sclerosing panencephalitis presenting as acute cerebellar ataxia and brain stem hyperintensities

BACKGROUND

Subacute sclerosing panencephalitis is a devastating neurodegenerative disease with a characteristic clinical course. Atypical presentations may be seen in 10% of the cases.

AIMS

To describe the atypical clinical and radiological features of SSPE in a child form endemic country.

METHODS

A 5-year-old boy presented with acute-onset cerebellar ataxia without associated encephalopathy, focal motor deficits, seizures or cognitive decline. He had varicella-like illness with vesicular, itchy truncal rash erupting one month prior to the onset of these symptoms. He underwent detailed neurological assessment, relevant laboratory and radiological investigations.

RESULTS

Neuroimaging revealed peculiar brain stem lesions involving the pons and cerebellum suggestive of demyelination. With a presumptive diagnosis of clinically isolated syndrome of demyelination, he was administered pulse methylprednisolone (30 mg/kg/day for 5 days). Four weeks later he developed myoclonic jerks. Electroencephalogram showed characteristic periodic complexes time-locked with myoclonus. CSF and serum anti-measles antibody titres were elevated (1:625).

CONCLUSION

Our report highlights that subacute sclerosing panencephalitis can present atypically as isolated acute cerebellar ataxia and peculiar involvement of longitudinal and sparing of transverse pontine fibres. The predominant brainstem abnormalities in the clinical setting may mimick acute demyelinating syndrome. Hence, it is important to recognize these features of subacute sclerosing panencephalitis in children, especially in the endemic countries.