Mustafa I. A. Hashem

A febrile seizure (FS) is the most common convulsive disorder in children. Activation of cytokine network is involved in FS pathogenesis. Adiponectin, leptin and IL-6 are the major adipocytokines secreted by fat cells. To date, only a few studies concerned the association of adipocytokines with febrile seizures. In this study, we tried to investigate serum and CSF levels of adiponectin, leptin, and interleukin-6 (IL-6); as adipocytokines, for the first time in Egyptian children with febrile seizures. This was a prospective cross-sectional study included one hundred patients with febrile seizure, and matched with age, gender, 100 children with febrile illness without seizures (febrile control, FC) and 100 healthy control group (HC). Serum and cerebrospinal fluid (CSF) levels of adiponectin, leptin, and (IL-6) were measured by enzyme-linked immunosorbent assay (ELISA) method. Serum adiponectin was significantly higher in children with FS (16.8 ± 3.7 ug/ml) and the FC group (18.3 ± 4.3 ug/ml) compared to the HC group (9.5 ± 2.2 ug/ml); P < 0.05, respectively. Serum leptin was significantly lower in children with FS (0.9 ± 0.3 ng/ml) compared to both the FC group (4.7 ± 1.2 ng/ml) and the HC group (1.8 ± 0.4 ng/ml); P < 0.01, respectively. Children with FS had significantly higher serum IL-6 levels (43.7 ± 11.7 ng/ml) than the FC group (21.9 ± 4.5 ng/ml) and the HC group (6.5 ± 1.8 ng/ml); P < 0.01, respectively. Patients with simple febrile seizures (SFS) had serum and CSF adiponectin levels similar to those with complex febrile seizures (CFS); (P > 0.05). Serum and CSF leptin levels were significantly lower in patients with CFS compared to the SFS group (P < 0.05). Serum and CSF IL-6 levels were significantly higher in patients with CFS compared to the SFS group (P < 0.01). On multivariate logistic regression analysis, the high serum IL-6 levels was the most significant risk factor associated with febrile seizures among studied children (OR: 6.2; 95 % CI: 3.58 –10.57; P = 0.0001). Our data brought a novel observation that some adipocytokines like leptin and IL-6 could be, at least in part, an aetiopathogenetic factor in the manifestation of febrile seizures in susceptible Egyptian children. Moreover, we observed a significant association between high CSF IL-6 levels and susceptibility to complex febrile seizures as did the low CSF leptin levels.

Febrile seizures are the most common form of childhood seizures. Among pro-inflammatory cytokines, interleukin-6 is the key acute-phase cytokine. To date, only a few studies concerned the association of interleukin-6 gene polymorphisms with febrile seizures.In this study, we aimed to investigate 3 cytokine single-nucleotide polymorphisms situated at positions –174 (G/C), –572 (G/C), and –597 (G/A) in the promoter region of the interleukin-6 gene for the first time in Egyptian children with febrile seizures. This was a case–control study included 100 patients with febrile seizure, and matched with age, gender, ethnicity 100 healthy control subjects. Interleukin-6 –174 (G/C), −572 (G/C), and −597 (G/A) polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), while the serum IL6 levels were measured by ELISA method. Compared to the controls subjects, the frequency of the −174 GG and −597 GG IL6 genotypes were observed to be increased in children with febrile seizures (OR: 4.17; 95 % CI: 1.86–9.49; P <0.01 and OR: 1.96; 95 % CI: 1.06–3.63;P <0.05, respectively). We found a significant positive association between the −597 GG genotype and susceptibility to complex febrile seizures as did the G allele at the same position (OR: 4.2; 95 % CI: 1.4–13.3 for the GG genotype; P <0.01) and (OR: 2.89; 95 % CI: 1.1–7.7 for the G allele; P 0.05). In conclusion, our data brought a novel observation that the presence of a G allele or GG genotype at the −174 and the GG genotype at the −597 positions of the promoter region of the interleukin-6 gene constitute risk factors for developing febrile seizures in Egyptian children. Moreover, we observed a significant positive association between the IL6 –597 GG genotype and susceptibility to complex febrile seizures as did the G allele at the same position. However, we found no association between IL6- genotypes and serum IL6 levels in patients with febrile seizures.