Clinical characteristics of febrile convulsions during primary HHV-6 infection.

OBJECTIVE: To clarify clinical characteristics of children with febrile convulsions during primary human herpesvirus 6 (HHV-6) infection. SUBJECTS AND METHODS: The clinical characteristics of first febrile convulsion were compared between those with and without primary HHV-6 infection in 105 children. HHV-6 infection was verified by culture or acute/convalescent anti-HHV-6 antibody titres. RESULTS: Primary infection with HHV-6 was seen in 21 of 105 patients with febrile convulsions (3 upper respiratory infection, 1 lower respiratory infection, and 17 exanthem subitum). 13 of 23 patients < 1 year, 19 of 79 patients with first febrile convulsion, and 2 of 15 with second convulsion were infected with HHV-6. The median age of patients with first febrile convulsion and HHV-6 was significantly lower than those without infection. The frequency of clustering seizures, long lasting seizures, partial seizures, and postictal paralysis was significantly higher among those with primary HHV-6 infection than among those without. The frequency of atypical seizures in 19 patients with first febrile convulsion associated with primary infection was significantly higher than in 60 patients without primary infection. The frequency in infants younger than 1 year of age was also significantly higher than that in 10 age matched infants without primary infection. CONCLUSIONS: These findings suggest that primary infection with HHV-6 is frequently associated with febrile convulsions in infants and young children and that it often results in the development of a more severe form of convulsions, such as partial seizures, prolonged seizures, and repeated seizures, and might be a risk factor for subsequent development of epilepsy.     

Urinary tract infection in febrile convulsions.

A retrospective review of the casenotes of 403 children admitted to hospital with febrile convulsions was performed to estimate the frequency of symptomatic urinary tract infection and examine medical practice in making this diagnosis. A total of 228 (56%) children had urine cultured: 150 bag specimens, 76 clean voided samples, and two suprapubic aspirates. There were 13 'probable' and six 'possible' infected urine samples together representing 5% of the whole study population (n = 403), 8% of those having urine cultured (n = 228), and 12% of those providing uncontaminated urine samples (n = 155). Those with first febrile convulsions and those aged under 18 months were more likely to have urine examined. Practices varied significantly between different hospitals. These results suggest that there has indeed been a need for practice guidelines, and that further audit of practice is required to assess their impact.     

Human herpes virus-6 and febrile convulsions

Parents of 996 children aged 4-5 years identified consecutively from the Oxford health visitor register were asked to complete a questionnaire about breathing disorders during sleep. A total of 782 (78.5%) was returned. Ninety five (12.1%) children were reported to snore on most nights. Habitual snoring was significantly associated with daytime sleepiness, restless sleep, and hyperactivity. The questionnaire responses were used to select two subgroups, one at high risk of a sleep and breathing disorder and a control group. These children (132 in total) were monitored at home with overnight video recording and oximetry, and had formal behavioural assessment using the Conners scale. Seven (7/66) children from the high risk group and none from the control group had obvious sleep disturbance consequent on snoring and upper airway obstruction. Thus our estimate of the prevalence of sleep and breathing disorders in this age group is 7/996 or 0.7%. The high risk group had significantly higher nocturnal movement, oxygen saturation dip rates, and overnight pulse rates than the controls. Maternal but not paternal smoking was associated with the high risk group. Parents and teachers thought those in the high risk group were more hyperactive and inattentive than the controls, but only their parents thought them more aggressive. Significant sleep and breathing disorders occur in about 0.7% of 4-5 year olds. Children whose parents report snoring and sleep disturbance have objective evidence of sleep disruption and show more behaviour problems than controls.     

幼儿急疹合并热性惊厥的临床特征

目的 探讨幼儿急疹合并热性惊厥的临床特征.方法 回顾性总结本院2005年1月至2008年2月确诊的幼儿急疹病例和热性惊厥病例,对幼儿急疹并热性惊厥的31例患儿的临床资料进行总结,与其他热性惊厥患儿及幼儿急疹未合并热性惊厥者对比,并结合文献进行分析.结果 幼儿急疹合并热性惊厥患儿占所有热性惊厥的17.1%(31/181),占2岁内热性惊厥的24.4%(31/127),占幼儿急疹患儿的15.7%(31/198);幼儿急疹并热性惊厥患儿出现热性惊厥的平均年龄为(0.85 4±0.38)岁,早于一般的热性惊厥患儿(2.41±1.30)岁,P<0.01;与不伴热性惊厥的幼儿急疹患儿比较,伴热性惊厥者的性别、年龄、最高体温、热程、出疹时间均无显著差别(P>0.05),而热性惊厥家族史有显著差别(P<0.05).结论 遗传因素是导致幼儿急疹并热性惊厥发作的一个危险因素;幼儿急疹并热性惊厥时一般预后良好,但要警惕发生严重中枢神经系统损伤的可能性,如癫痫.对于1岁内初次发热并出现热性惊厥的患儿要注意幼儿急疹的可能.     

Treatment of febrile convulsions]

Information and reassurance of parents are essential before considering therapeutic measures following a first febrile seizure. It must be emphasized that, although impressive, febrile convulsions are essentially benign, and that in the majority of cases there will be no recurrence. Apart from that, therapeutic measures are of limited efficacy in order to prevent reocurrence. The correct use of antipyretic treatment during febrile episodes must be specified. Due to its several inconveniences, oral diazepam as an intermittent prophylaxis should be only considered in case of multiple reoccurrences. There is little place for continuous anticonvulsant treatment.     

Nonfebrile seizures after febrile convulsions: possible role of chronic cytomegalovirus infection

Twelve hundred children with convulsions when feverish were studied during a period of five years. Among them 52 subjects (4.33%) developed nonfebrile seizures after a period of eight months to five years from the first febrile convulsion (group A). Twenty-three children had neither afebrile seizures nor EEG abnormalities during the period of observation (group B). The two groups were comparable for age of the first febrile convulsion onset, sex, and socioeconomic status. None had risk factors for subsequent epilepsy or clinical signs of congenital cytomegalovirus infection. The isolation rate of CMV from urine was 53.84% in patients of group A, 26.09% in children of group B, and 26.83% in healthy control children. Twelve CMV-positive children from group A were followed for one to more than three years. In five of seven children with persisting EEG abnormalities, cytomegaloviruria was still present 13 to 41 months after the first isolation, whereas none of five patients with normal electroencephalograms had viruria after a comparable period. We found that CMV-positive children generally lacked cell-mediated immunity to the virus, whereas CMV-negative patients had positive reactions. Our data suggest a correlation between persistence of neurologic abnormalities and CMV excretion in children with nonfebrile seizures and CMV infection.     

Basal ganglia infarction associated with HHV-6 infection

A 6 year old boy presented with meningoencephalitis and was found to have serological evidence of acute human herpes virus-6 (HHV-6) infection. He did not develop symptomatic seizures or the rash of exanthum subitum (roseola). His course was marked by severe spastic quadriparesis associated with radiological evidence of basal ganglia infarction. HHV-6 infection should be considered in any child with acute meningoencephalitis.     

Current therapy of febrile convulsions]

The author gives a review on clinical features and therapeutic aspects of febrile seizures. The treatment with different anticonvulsants is described. Differentiation between simple and complicated febrile convulsions seem to be useful for therapeutic management.     

Viral infections and recurrences of febrile convulsions

To determine whether complicated febrile seizures occur more often in children with a proven viral infection, we performed viral examinations on 144 children with febrile convulsions, of whom 112 had simple and 32 had complicated seizures. A diagnosis of virus infection was verified in 46% of the former patients and 53% of the latter. Three adenoviruses, one parainfluenza virus type 2 and one type 3, one respiratory syncytial virus, one echovirus type 11, one herpes simplex virus type 2, and one influenza B virus were isolated from the cerebrospinal fluid. A simple febrile convulsion occurred in seven children with a positive cerebrospinal fluid viral isolation, and two had a complex febrile seizure. In a follow-up of 2 to 4 years (mean 3.3 years), 21 of the 107 children with simple seizures (19.6%) and 3 of the 32 children with complicated seizures (9.4%) had recurrent febrile seizures. The children with positive evidence for a viral infection, even with a virus isolated from the cerebrospinal fluid, had no more recurrences than those without any proven viral infection. We conclude that children with a proven viral infection have no worse prognosis than those without.     

Role of viruses in febrile convulsions.

A disseminated viral illness was demonstrated by isolating a virus from the CSF, blood or urine in 27% of 73 children who were admitted to hospital after a first febrile convulsion. However, a viral aetiology could be implicated for 86% of the children after combining results of tissue culture, electron microscopy, mouse inoculation, complement fixation tests, and interferon assay. Parallel bacterial cultures showed a possible pathogen in 29% of children, but in only 4% was the pathogen isolated from the CSF, blood, or urine. No correlation was found between the nature of the pathogen (or evidence of its dissemination) and the severity of the convulsion, degree of fever, CSF protein, CSF white cells, or the WBC. The results suggest that a febrile convulsion could be a response to invasion of the blood stream or central nervous system by a micro-organism which is usually a virus. Invasion may be of such brief duration that successful isolation of the virus from the blood, CSF, or urine in not more commonly achieved.     

Duration of admission for febrile convulsions?

Records of 199 children aged 5 to 71 months (mean 22.8) admitted after febrile convulsion were examined. Although 32 had recurrent convulsions (some before admission) none suffered a convulsion more than 24 hours after hospital admission.