Benign partial epilepsy in infancy long-term outcome and marginal syndromes

Risk factors predicting intractability in focal epilepsy in children under 3 years of age: A cohort study

BACKGROUND

Focal onset epilepsy carries a higher risk of intractability than generalized onset epilepsy. Knowledge of the risk factors of intractability will help guide the treatment of children with focal epilepsy. In addition to risk factors present at initial diagnosis, the evolution of clinical and electroencephalographic features may also play a role in predicting intractability.

METHODS

A prospective cohort study was done on children aged one month to three years with newly diagnosed focal epilepsy. Initial treatment of carbamazepine was given according to a standard protocol after assessment of clinical manifestations, neurologic and developmental status, EEG, and brain MRI. Depending on response to therapy, subjects may also receive valproic acid or phenobarbitone following the protocol. Follow-up was done in the second week and every month thereafter. At the end of the study period, seizure type was re-assessed and a repeat neurological and developmental examination and EEG was obtained to evaluate the role of clinical and EEG evolution in predicting intractability.

RESULTS

Out of 71 subjects, 21 (29.6%) had intractable epilepsy at the end of the study period. Age of onset (p = 0.216) and neurological status (p = 0.052) were not associated with intractable epilepsy. On logistic regression analysis, evolution of seizure type (p < 0.001; RR 56.45; 95%CI 6.56 to 485.85) and evolution of background EEG rhythm (p < 0.001; RR 56.51; 95%CI 2.77 to 1152.16) were significantly associated with intractable epilepsy.

CONCLUSIONS

Changes in seizure type and baseline EEG rhythm may predict intractability in children one month to three years of age with focal epilepsy.

Clinical characteristics, treatment, and long-term outcomes in children suffering from benign convulsions with mild gastroenteritis: a retrospective study

BACKGROUND

Benign convulsions with mild gastroenteritis (BCWG) is a common condition in children in Asia and is generally not associated with pH or electrolyte imbalances. When BCWG is diagnosed, a lumbar puncture is usually recommended to rule out potential intracranial infections. This study examined the clinical characteristics of BCWG and evaluated the necessity of lumbar puncture.

METHODS

Medical records of children admitted to the First Hospital of Jilin University with BCWG between January 2018 and May 2019 were reviewed and analyzed. Children were stratified by rotavirus positivity or lumbar puncture status. Clinical characteristics and long-term outcomes were compared between groups.

RESULTS

A total of 51 children were included in the analyses (55.1% rotavirus [HRV] positive). The average age of convulsion onset was 21.12 ± 7.44 months, the male-to-female ratio was 1.8:1, and convulsions occurred primarily between October 2018 and April 2019. The main clinical presentations of BCWG were convulsions, vomiting, diarrhea, and fever. Convulsions occurred predominantly two days after diagnosis of gastroenteritis, were mainly generalized tonic-clonic with 88.2% of children having ≤ 3 convulsions per episode, and had a mean duration of 2.0 minutes (interquartile range [IQR]: 1.0, 3.0). Children with BCWG had mild metabolic acidosis (HCO₃^- 17.82 ± 3.63 mmol/L) with an elevated anion gap (AG; 20.98 ± 3.00 mmol/L), mild hyponatremia (134.56 ± 2.85 mmol/L), and slightly increased levels of creatine kinase myocardial band (CKMB). HRV + children had more severe acidosis and higher CKMB levels. Cerebrospinal fluid (CSF) samples collected via lumbar puncture were normal. No developmental abnormalities were noted as assessed by the Social Life Ability Scale.

CONCLUSIONS

BCWG is a situation-related seizure, with clinical presentations of tonic-clonic or focal convulsions and mild gastroenteritis (vomiting, diarrhea). Mild metabolic acidosis and hyponatremia may exist. The prognosis of the disease is favorable; lumbar puncture and long-term antiepileptics are unnecessary and should not be recommended.

Splenial Lesions in Benign Convulsions With Gastroenteritis Associated With Rotavirus Infection

OBJECTIVE

To investigate clinical risk factors for acute magnetic resonance imaging (MRI) abnormalities in patients with benign convulsions with mild gastroenteritis or benign infantile epilepsy.

STUDY DESIGN

We investigated clinical and diffusion-weighted imaging findings in 32 patients with benign convulsions with mild gastroenteritis and 22 patients with benign infantile epilepsy who underwent MRI within seven days of seizure onset between 2010 and 2015.

RESULTS

Diffusion-weighted imaging showed signal hyperintensity in the splenium of the corpus callosum in seven patients with benign convulsions with mild gastroenteritis, but no abnormalities in patients with benign infantile epilepsy. Patients with benign convulsions with mild gastroenteritis with splenial lesions showed a higher rate of rotavirus detection from feces (P = 0.006), higher serum level of C-reactive protein (P = 0.04), and shorter interval between seizure onset and MRI (P = 0.002) than patients with benign convulsions with mild gastroenteritis without splenial lesions. Multivariate analysis revealed rotavirus infection as a significant risk factor for splenial lesions on diffusion-weighted imaging in patients with benign convulsions with mild gastroenteritis (P = 0.02).

CONCLUSIONS

Splenial lesions are often seen during acute period in patients with benign convulsions with mild gastroenteritis. Rotavirus infection is a risk factor for splenial lesions in patients with benign convulsions with mild gastroenteritis, suggesting the role of rotavirus to cause edema in the corpus callosum. From our observations, benign convulsions with mild gastroenteritis with a splenial lesion on diffusion-weighted imaging suggests good outcomes, and extensive evaluation of these patients may be unnecessary.

Difficulty of Early Diagnosis and Requirement of Long-Term Follow-Up in Benign Infantile Seizures

PURPOSE

We investigated whether benign infantile seizures can be diagnosed in the acute phase.

METHODS

We retrospectively analyzed the medical records of 44 patients initially diagnosed with acute phase benign infantile seizures. All patients were followed for more than 12 months, and we reviewed patients' psychomotor development and presence or absence of seizure recurrence at the last visit. Patients were divided into the following three groups according to the final diagnosis: benign infantile seizures, benign infantile seizures associated with mild gastroenteritis, and non-benign infantile seizures. We defined benign infantile seizures associated with mild gastroenteritis and benign infantile seizures as those associated with normal psychomotor development and no seizure recurrence 3 months after onset of the first seizure, whereas non-benign infantile seizures were associated with delayed psychomotor development and/or seizure recurrence after 3 months of onset of the first seizure. We analyzed the clinical features in the acute phase and compared them between the groups.

RESULTS

The median age of seizure onset was 7.6 months. A final diagnosis of benign infantile seizures associated with mild gastroenteritis was made in three patients. In the remaining 41 patients, the final diagnosis was benign infantile seizures in 30 (73.2%) and non-benign infantile seizures in 11 (26.8%). In the non-benign infantile seizure group, intellectual disability was diagnosed in eight patients and seizure recurrence in six. There were no significant differences in clinical features between the groups in the acute phase, such as seizure type or seizure duration.

CONCLUSION

About 30% of patients initially diagnosed as having benign infantile seizures did not experience a benign clinical course. Our findings suggest that clinical features in the acute phase are not helpful for predicting benign outcomes in benign infantile seizures and that only long-term follow-up can discriminate benign infantile seizures from non-benign infantile seizures.

Single nucleotide variations in CLCN6 identified in patients with benign partial epilepsies in infancy and/or febrile seizures

Nucleotide alterations in the gene encoding proline-rich transmembrane protein 2 (PRRT2) have been identified in most patients with benign partial epilepsies in infancy (BPEI)/benign familial infantile epilepsy (BFIE). However, not all patients harbor these PRRT2 mutations, indicating the involvement of genes other than PRRT2. In this study, we performed whole exome sequencing analysis for a large family affected with PRRT2-unrelated BPEI. We identified a non-synonymous single nucleotide variation (SNV) in the voltage-sensitive chloride channel 6 gene (CLCN6). A cohort study of 48 BPEI patients without PRRT2 mutations revealed a different CLCN6 SNV in a patient, his sibling and his father who had a history of febrile seizures (FS) but not BPEI. Another study of 48 patients with FS identified an additional SNV in CLCN6. Chloride channels (CLCs) are involved in a multitude of physiologic processes and some members of the CLC family have been linked to inherited diseases. However, a phenotypic correlation has not been confirmed for CLCN6. Although we could not detect significant biological effects linked to the identified CLCN6 SNVs, further studies should investigate potential CLCN6 variants that may underlie the genetic susceptibility to convulsive disorders.

Evaluation of clinical course and neurocognition in children with self-limited infantile epilepsy in a Turkish cohort study

The outcome of children with self-limited infantile epilepsy was reported to be normal psychosocial and cognitive development as a characteristic criterion. We aimed to investigate the clinical course and neurocognitive outcome in children with self-limited infantile epilepsy in a Turkish cohort. The clinical course, electroencephalographic (EEG) characteristics, neuroimaging, treatment, and outcome of children with self-limited infantile epilepsy were retrospectively analyzed. All infants were reevaluated with the Denver Developmental Screening Test in addition to neurologic examination. Of 44 patients, self-limited familial infantile epilepsy was diagnosed in 8 infants (18.2%) and self-limited nonfamilial infantile epilepsy in 28 (63.6%). Interictal EEGs and neurologic examinations were normal in all cases. Fine motor and gross motor skills, language, adaptive personal/social skills were near-normal in all patients with self-limited familial infantile epilepsy. Delay in language parameters was observed in 2 infants with self-limited nonfamilial infantile epilepsy. Language skills should be thoroughly evaluated with detailed neurocognitive screening tests in patients with self-limited infantile epilepsy.

Benign convulsion with mild gastroenteritis

Benign convulsion with mild gastroenteritis (CwG) is a type of afebrile seizure that occurs in children. CwG is defined as a convulsion in a previously healthy child with no known central nervous system infection or encephalopathy, accompanying mild diarrhea without fever, electrolyte imbalance, or moderate to severe dehydration. Convulsions in CwG are characterized by multiple brief episodes of generalized or focal seizures. Although the etiology and pathophysiology have yet to be fully explained, many pathogenic mechanisms have been proposed including the possibility of direct invasion of the central nervous system by a gastrointestinal virus such as rotavirus or the possibility of indirect influence by the production and effects of certain mediators. The electroencephalogram findings are benign and long-term antiepileptic treatment is typically not required. Long-term prognosis has been favorable with normal psychomotor development. This review provides a general overview of CwG with the goal of allowing physicians practicing in the field of pediatrics to better recognize this unique entity and, ultimately, to minimize unnecessary evaluation and treatment.

Benign convulsions with mild gastroenteritis: is it associated with sodium channel gene SCN1A mutation?

Benign convulsions with mild gastroenteritis were afebrile seizures associated with gastroenteritis in previously healthy infants or young children. It has been thought to be a continual spectrum of benign infantile convulsions because of overlapping clinical pictures. Recently, molecular genetic studies have suggested a channelopathy in benign infantile convulsions. The authors prospectively studied the clinical features of benign convulsions with mild gastroenteritis in Taiwanese children and clarified the relationship between neuronal sodium channel alpha 1 subunit (SCN1A) gene and benign convulsions with mild gastroenteritis. The clinical pictures in their patients were similar to those of previous studies except for the low rate of positive rotavirus antigen in the stool, which may indicate a season-related viral infection. No mutations in the SCN1A gene were identified in all patients. This study suggested that SCN1A mutations are probably not associated with benign convulsions with mild gastroenteritis. Other possible pathogenic mechanisms need to be researched in the future.