The effect of body temperature on the "periodic complexes" of subacute sclerosing leuconencephalitis (SSLE)

Expanding the Spectrum of EEG Periodic Discharges in Subacute Sclerosing Panencephalitis: A Case Report

Background Atypical electroencephalogram (EEG) abnormalities emerge in patients with subacute sclerosing panencephalitis (SSPE), especially in cases with an atypical clinical presentation that can lead to diagnostic difficulties.

Case Report In this article, we presented a case of SSPE with an atypical onset with epileptic seizures and Parkinson's features. The neurological examination during the initial evaluation of the patient showed extrapyramidal syndrome, hyperreflexia, intention tremor, and dysmetria. Cranial magnetic resonance imaging was normal. Video EEGs were performed in wakefulness and sleep. In wakefulness, multiple brief seizures (1–1.5 seconds were recorded, consisting of gradual bending of the body forward and to the right that lacked the sudden characteristic of myoclonia. During those episodes, we recorded generalized epileptiform activity of 4 or 5 sharp waves, with higher amplitude in the anterior regions, in some of the paroxysms superimposed on a slow wave or followed by a high amplitude slow wave. The paroxysms appeared periodically every 15 to 30 seconds. However, 2 months later, the EEG showed typical periodic generalized activity of biphasic/triphasic slow waves (Radermecker complexes), accompanied by myoclonias.

Conclusion We reported a peculiar EEG pattern in a patient with SSPE that consists of periodic generalized activity of sharp waves. Atypical EEG patterns can appear when the disease progresses, but initially too, before typical periodic complexes and can complicate the diagnostic process.

Behaviors associated with fever in children with autism spectrum disorders

OBJECTIVE

Clinical case reports have suggested that the behaviors of children with autism spectrum disorders may improve with fever. The purpose of this study was to investigate the effect of illness on behaviors of children with autism spectrum disorders. Understanding the role of fever, if any, may be informative regarding causative mechanisms of and treatment opportunities for autism.

METHODS

We conducted a prospective study of 30 children (aged 2-18 years) with autism spectrum disorders during and after an episode of fever. Parent responses to the Aberrant Behavior Checklist were collected during fever (body temperature > or = 38.0 degrees C/100.4 degrees F), when fever had abated and the child was asymptomatic, and when the child had been fever-free for 7 days. Data were compared with those collected from parents of 30 age-, gender-, and language skills-matched afebrile children with autism spectrum disorders during similar time intervals.

RESULTS

Fewer aberrant behaviors were recorded for febrile patients on the Aberrant Behavior Checklist subscales of irritability, hyperactivity, stereotypy, and inappropriate speech compared with control subjects. Per expectation, lethargy scores were greater during fevers, and all improvements were transient. Data from patients with fever were stratified on variables related to illness severity. In the majority of these subgroup comparisons, the data suggested that effects from fever persisted in the less sick patients as well as in those with more severe illness.

CONCLUSIONS

We documented behavior change among children with autism spectrum disorders during fever. The data suggest that these changes might not be solely the byproduct of general effects of sickness on behavior; however, more research is needed to prove conclusively fever-specific effects and elucidate their underlying biological mechanisms (possibly involving immunologic and neurobiological pathways, intracellular signaling, and synaptic plasticity).

Atypical EEG findings in subacute sclerosing panencephalitis

OBJECTIVE

To evaluate atypical electroencephalographic features in subacute sclerosing panencephalitis (SSPE) and to detect its relation to clinical features.

METHODS

Twenty-two patients aged 2-17 years (mean 9.4 years) with definite diagnosis of SSPE were studied. Their clinical data and EEG records were reviewed retrospectively. All EEG records were analysed for features of periodic complexes (PCs) in relation to age, age at onset, clinical stage and the rate of progression as well as duration of the disease.

RESULTS

Classical periodic complexes of SSPE were found in EEGs of 13 patients (group I). Atypical patterns were observed in EEGs of nine patients (group II). Two new atypical findings were identified: prolonged discharges which include sharp waves and slow waves for 4-7 s followed by suppression for 1-4s; and periodic complexes which consist of four or five sharp waves in every 2 s. We observed atypical EEG patterns were more frequently in Stage III, acute form, and the disease duration was longer than in the typical group.

CONCLUSIONS

Atypical EEG patterns in SSPE might be related to the progression of the disease, but this theory needs further longitudinal studies.

SIGNIFICANCE

We suggest atypical EEG patterns might be observed more frequently in patients with severe neurologic disability, more rapidly progressive disease and longer duration of disease.

Periodic electroencephalographic pattern in subacute sclerosing panencephalitis modified by preexisting damaged cerebral hemisphere

We report a 15 year old girl with a childhood hemiplegia, who developed a recent progressive intellectual decline associated with elevated globulins and measles antibody titres in the cerebrospinal fluid, indicating a diagnosis of subacute sclerosing panencephalitis (SSPE). The magnetic resonance imaging revealed left hemispheric atrophy concordant with a long-standing right hemiplegia, and electroencephalography exhibited lateralized periodic complexes (PCs) over the right hemisphere concordant with left-sided myoclonic jerks. The modification of PCs in our patient due to preexisting damaged cerebral hemisphere illustrate that a fairly functional cortex and subcortical white matter are needed for the expression of the PCs of SSPE.

Dynamic diseases in neurology and psychiatry

Thirty-two (32) periodic diseases of the nervous system are identified in which symptoms and/or signs recur. In 10/32, the recurrence of a symptom complex is one of the defining features of the illness, whereas in 22/32 oscillatory signs occur in the setting of an ongoing nervous system disorder. We discuss the possibility that these disorders may be dynamic diseases. (c) 1995 American Institute of Physics.

Subacute sclerosing panencephalitis: serial electroencephalographic studies

A total of 42 EEGs from five patients with subacute sclerosing panencephalitis were studied. Periodic complexes were noticed in 35 (83%) of these. The interval between the complexes shortened in all patients with progression of the illness. The gradual EEG changes may reflect the increasing number of infected cells as well as an on-going accumulation of immature virus structures. The records without complexes were either from the early onset (one record) or terminal stage (six records).

A study of periodicity and structure of EEG complexes in a case of SSPE

This is a preliminary study of the EEG complexes of SSPE. This consisted of an analysis of the time and frequency domain of the complexes recorded in different test situations. The authors examined the periodicity of complexes and changes in the intercomplex interval succession and, in another approach, the shape of the complex and the constant properties of its structure. Analysing the findings obtained and the data of earlier authors, they suggested a working hypothesis according to which a regulated trigger mechanism 'sparks off' the structures 'sensitive' to this in different regions of the cortex, in which simultaneous and successive sub-processes lasting several hundred milliseconds then occur; the periodic complex appearing in SSPE is that part of this that can be observed in the EEG.