Risk Of Febrile Seizures Research Articles

Polymorphisms in the interleukin-1β (IL-1B) and interleukin-1α (IL-1A) genes on risk of febrile seizures: a meta-analysis.

The aim of the current study was to clarify the role of four common genetic polymorphisms in the interleukin-1β (IL-1B) and interleukin-1α (IL-1A) genes on risk of febrile seizures (FS) by means of meta-analyses. We searched for studies published until February 2018 using ISI Web of Science, Pubmed, Wanfang, and Chinese National Knowledge Infrastructure databases. The pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using MetaAnalyst version Beta 3.13. Seventeen case-control studies were included for meta-analysis. For the IL-1B rs16944 polymorphism, the summary analysis of studies conducted among Caucasian populations showed a significant association in the CT+TT versus CC contrast (OR 1.434, 95% CI 1.153-1.785), while the pooled analysis for Asian populations yielded a significant estimate in the TT versus CC+CT comparison (OR 1.393, 95% CI 1.051-1.846). No association was observed between the IL-1B rs1143627, IL-1B rs1143634, and IL-1A rs1800587 polymorphisms and FS risk. Sensitivity analyses excluding studies showing deviation from Hardy-Weinberg equilibrium did not alter conclusions. The findings of our meta-analysis suggest that the IL-1B rs16944 polymorphism may be an important genetic determinant for FS in Caucasian and Asian populations.

Exposure to traffic noise and air pollution and risk for febrile seizure: a cohort study

Objectives Exposure to traffic noise and air pollution is suspected to increase susceptibility to viral infections - the main triggering factor for febrile seizures. No studies have examined these two exposures in relation to febrile seizures. We aimed to investigate whether exposure to road traffic noise and air pollution are associated with risk of febrile seizures in childhood. Methods From our study base of 51 465 singletons from a national birth cohort, we identified 2175 cases with febrile seizures using a nationwide registry. Residential address history from conception to six years of age were found in national registers, and road traffic noise (L den) and air pollution (NO 2) were modeled for all addresses. Analyses were done using Cox proportional hazard model with adjustment for potential confounders, including mutual exposure adjustment. Results An interquartile range (IQR) increase in childhood exposure to road traffic noise and air pollution was associated with an 11% [incidence rate ratio (IRR) 1.11, 95% confidence interval (CI) 1.04-1.19) and 5% (IRR 1.05, 95% CI 1.02-1.07) higher risk for febrile seizures, respectively, after adjustment for potential confounders. Weaker tendencies were seen for pregnancy exposure. In models with mutual exposure adjustment, the estimates were slightly lower, with IRR of 1.08 (95% CI 1.00-1.16) and 1.03 (95% CI 0.99-1.06) per IQR increase in childhood exposure to road traffic noise and air pollution, respectively. Conclusions This study suggests that residential exposure to road traffic noise and air pollution is associated with higher risk for febrile seizures.

Iron status among under-five children with first febrile convulsion and subsequent febrile convulsion

Objective: The objective of this study is to estimate the iron status using hemoglobin (Hb), red cell indices, serum iron, plasma ferritin, total iron binding capacity (TIBC), and transferrin saturation (TSAT) in children with first febrile convulsion (FFC) and subsequent FC (SFC). Methods: The study was conducted in a tertiary care teaching hospital among children aged 6 months–5 years with first and subsequent episodes of the simple FC taking cases and controls in a ratio of 2:2:1. Consecutive cases and concurrent controls were selected for the study. Controls were children of the same age group with short febrile illness but without any seizures. After informed consent from parents, detailed history was taken; clinical examination and blood investigations were done to estimate iron status in both cases and controls. Laboratory tests included Hb, hematocrit( Hct), red cell indices, peripheral smear, red cell distribution width (RDW), serum iron concentration, plasma ferritin, TIBC, and TSAT. The data were then analyzed statistically using SPSS software. Results: 44 cases with FFC, 44 with SFC, and 22 controls were included in the study. The mean Hb, Hct, red cell indices, and RDW between the three groups did not show any significant difference. The mean serum ferritin was significantly lower in the SFC group compared to the control group (p=0.005). The mean serum TIBC was significantly higher in the SFC group compared to the control group (p=0.004) and also the SFC group compared to the FFC group (p=0.022). Conclusions: Poor iron status in subsequent febrile seizures indicates that iron deficiency is associated with subsequent seizures. Hence, screening for iron status rather than Hb level estimation should be considered for children presenting with or at high risk for febrile seizures.

The effect of antipyretics on immune response and fever following receipt of inactivated influenza vaccine in young children.

Antipyretics reduce fever following childhood vaccinations; after inactivated influenza vaccine (IIV) they might ameliorate fever and thereby decrease febrile seizure risk, but also possibly blunt the immune response. We assessed the effect of antipyretics on immune responses and fever following IIV in children ages 6 through 47 months. Over the course of three seasons, one hundred forty-two children, receiving either a single or the first of 2 recommended doses of IIV, were randomized to receive either oral acetaminophen suspension (n = 59) or placebo (n = 59) (double-blinded) or ibuprofen (n = 24) (open-label) immediately following IIV and every 4-8 h thereafter for 24 h. Blood samples were obtained at enrollment and 4 weeks following the last recommended IIV dose. Responses to IIV were assessed by hemagglutination inhibition assay (HAI). Seroprotection was defined as an HAI titer ≥1:40 and seroconversion as a titer ≥1:40 if baseline titer <1:10 or four-fold rise if baseline titer ≥1:10. Participants were monitored for fever and other solicited symptoms on the day of and day following IIV. Significant differences in seroconversion and post-vaccination seroprotection were not observed between children included in the different antipyretic groups and the placebo group for the vaccine antigens included in IIV over the course of the studies. Frequencies of solicited symptoms, including fever, were similar between treatment groups and the placebo group. Significant blunting of the immune response was not observed when antipyretics were administered to young children receiving IIV. Studies with larger sample sizes are needed to definitively establish the effect of antipyretics on IIV immunogenicity.

Febrile Seizure Risk after Vaccination in Children One to Five Months of Age

BackgroundThe risk of febrile seizure is temporarily increased for a few days after the administration of certain vaccines in children aged six to 23 months. Our objective was to determine the febrile seizure risk following vaccination in children aged one to five months, when six different vaccines are typically administered. MethodsWe identified emergency department visits and inpatient admissions with International Classification of Diseases, Ninth Revision, febrile seizure codes among children enrolled in nine Vaccine Safety Datalink participating health care organizations from 2006 through 2011. Febrile seizures were confirmed by medical record abstraction. We used the self-controlled risk-interval method to compare the incidence of febrile seizure during postvaccination days 0 to 1 (risk interval) versus days 14 to 20 (control interval). ResultsWe identified 15 febrile seizure cases that occurred after 585,342 vaccination visits. The case patients were aged three to five months. The patients had received a median of four (range two to six) vaccines simultaneously. The incidence rate ratio of febrile seizure after vaccination was 23 (95% confidence interval 5.13 to 100.8), and the attributable risk was 3.92 (95% confidence interval 1.68 to 6.17) febrile seizure cases per 100,000 persons vaccinated. ConclusionsVaccination in children aged three to five months was associated with a large relative risk of febrile seizure on the day of and the day after vaccination, but the risk was small in absolute terms. Postvaccination febrile seizure should not be a concern for the vast majority of children receiving vaccines, but clinicians might take this risk into consideration when evaluating and treating children susceptible to seizures precipitated by fever.

Study of iron deficiency as a risk factor for first episode of simple febrile siezure

Background: Febrile seizure are seizure that occur between the age of 6 month to 60 months with a temperature of 100.4f or higher, that are not the result of central nervous system infection or any metabolic imbalance and that occur in the absence of a history of prior afebrile seizure. Febrile seizures are the commonest cause of seizures in children, occuring in 2-5% of children. The maximum age of febrile convulsion occurrence is 14-18 months, which overlap with the maximum prevalence of iron deficiency anaemia which is 1-2 year old. 7 So far, the dilemma of cause of febrile seizure could not be solved. Standard text book still mention iron deficiency is associated with an increased risk of febrile seizure, thus screening for that problem and treating it appears appropriate.Methods: This case control study was done from June 2015 to December 2016. 60 cases of first episode of simple febrile seizure in age group of 6 month to 5 years were included in the study. A control group was selected from age and sex matched children admitted with febrile illness but without seizure. In all cases detailed clinical history, anthropometry, clinical sign of iron deficiency, CNS examination, CBC, PBF, Red cell indices, serum iron, serum ferritin and serum TIBC level was done. These were analysed in three groups mild, moderate, severe deficiency of anemia. A clinical correlation is tried to establish between overt and subtle iron deficiency with seizure.Results: Majority of subjects with first episode of simple febrile seizure were males (63.3%). Majority of cases of febrile seizure occur in the 6-24 months age group (83.3%). Incidence of anemia among case group subjects was 90.0% whereas the same in control group was 30 %. Mean RDW and TIBC levels in cases were significantly higher as compared to that in controls. MCV, Mean Serum ferritin and Serum Iron levels in cases were significantly lower as compared to that in controls.Conclusions: The findings in present study established an association between iron deficiency anemia and first episode of simple febrile seizures.

Evaluation of Combination Measles-Mumps-Rubella-Varicella Vaccine Introduction in Australia

Incorporating combination vaccines, such as the measles-mumps-rubella-varicella (MMRV) vaccine, into immunization schedules should be evaluated from a benefit-risk perspective. Use of MMRV vaccine poses challenges due to a recognized increased risk of febrile seizures (FSs) when used as the first dose in the second year of life. Conversely, completion by age 2 years of measles, mumps, rubella, and varicella immunization may offer improved disease control. To evaluate the effect on safety and coverage of earlier (age 18 months) scheduling of MMRV vaccine as the second dose of measles-containing vaccine (MCV) in Australia. Prospective active sentinel safety surveillance comparing the relative incidence (RI) of FSs in toddlers given MMRV and measles-mumps-rubella (MMR) and a national cohort study of vaccine coverage rates and timeliness before and after MMRV vaccine introduction were conducted. All Australian children aged 11 to 72 months were included in the coverage analysis, and 1471 Australian children aged 11 to 59 months were included in the FS analysis, with a focus on those aged 11 to 23 months. MMRV vaccine safety, specifically, the RI of FSs after MMRV vaccine at age 18 months, compared with risk following MMR vaccine and vaccine uptake for 2-dose MCV and single-dose varicella vaccine, focusing on timeliness. Of the 1471 children, the median age at first FS was 21 months (interquartile range [IQR], 14-31 months). Three hundred ninety-one children were aged 11 to 23 months and had at least 1 FS included in the analysis; of these, 207 (52.9%) were male. A total of 278 children (71.1%) had received MMR followed by MMRV vaccine, 97 (24.8%) had received MMR vaccine only, and 16 (4.1%) had received neither vaccine. There was no increased risk of FSs (RI, 1.08; 95% CI, 0.55-2.13) in the 5 to 12 days following MMRV vaccine given as the second MCV to toddlers. Febrile seizures occurred after dose 1 of MMR vaccine at a known low increased risk (RI, 2.71; 95% CI, 1.71- 4.29). Following program implementation, 2-dose MCV coverage at age 36 months exceeded that obtained at age 60 months in historical cohorts recommended to receive MMR vaccine before school entry, and on-time vaccination increased by 13.5% (from 58.9% to 72.4%). Despite no change in the scheduled age of varicella vaccine, use of MMRV vaccine was associated with a 4.0% increase in 1-dose varicella vaccine coverage. To our knowledge, this is the first study to provide evidence of the absence of an association between use of MMRV vaccine as the second dose of MCV in toddlers and an increased risk of FSs. Incorporation of MMRV vaccine has facilitated improvements in vaccine coverage that will potentially improve disease control.

Progress of adverse effect of routine vaccination in children with epilepsy

Routine vaccination is a most important way to prevent and control various kinds of infection disease, however, concerns about epileptic diseases after vaccination worries patients and health care providers.Many studies have shown that the risk of febrile seizure (FS) increases after measles-mumps-rubella (MMR) and iphtheria-tetanus-pertussis (DTP) vaccine, but this increase is associated with the fever after vaccine.The prognosis of vaccine related FS is similar to non-vaccine FS.Moreover, no evidence has shown that vaccine is related with non-febrile seizure and epileptic encephalopathy. Key words: Routine vaccination; Febrile seizure; Epilepsy; Epileptic encephalopathy

The Risk of Febrile Seizures Following Influenza and 13-Valent Pneumococcal Conjugate Vaccines

BackgroundEvidence on the risk of febrile seizures (FS) after vaccination with inactivated influenza vaccine (IIV) and 13-valent pneumococcal conjugate vaccine (PCV13) is mixed. Among children 6–23 months, we examined the risk of FS following IIV and PCV13 during the 2013–14 and 2014–15 influenza seasons, for which vaccine virus strains were the same.MethodsWe used claims data from 4 large national insurers in the FDA-sponsored Sentinel Initiative, which was developed to monitor the safety of FDA-regulated medical products. With a self-controlled risk interval design, the risk of FS in 0–1 days following IIV and following PCV13 was compared with a comparison interval (14–20 days), adjusting for confounding by age, calendar time, and concomitant vaccination with the other vaccine. In exploratory analyses, we assessed whether the effect of IIV is modified by concomitant administration of PCV13.ResultsDuring the study period, 355,486 children received IIV and 581,868 received PCV13. We observed an incidence rate ratio (IRR) of 1.12 (95% CI 0.80, 1.56) for the risk of FS following IIV after adjustment for age, calendar time and concomitant PCV13. PCV13 was associated with an increased risk of FS (IRR adjusted for age, calendar time and concomitant IIV, 1.80, 95% CI 1.29, 2.52). The attributable risk for PCV13 ranged from 0.33 to 5.16 per 100,000 doses.The age and calendar-time adjusted IRR comparing exposed time to unexposed time was greater for concomitant IIV and PCV13 (IRR 2.80, 95% CI 1.63, 4.83), as compared with that for PCV13 without concomitant IIV (IRR 1.54, 95% CI 1.04, 2.28). However, the formal test assessing for interaction between IIV and PCV13 was not statistically significant.ConclusionWe found an elevated risk of FS after PCV13 vaccine but not after IIV, when adjusting for concomitant administration of the other vaccine. We found some evidence to suggest that concomitant administration of IIV with PCV13 might interact to increase the risk beyond the independent effects of PCV13, but the study was not powered to assess this interaction. The risk of seizures associated with PCV13 is low compared with a child’s lifetime risk of FS. Findings should be interpreted in the context of the importance of preventing influenza and pneumococcal infections in young children.Disclosures L. Li, sanofi pasteur: The author is currently employed by Sanofi Genzyme, which shares the same parent company as sanofi pasteur, the manufacturer of the Flu vaccine. However, the work was done while this author was still employed by Harvard Pilgrim Health Care Institute., No financial benefit received

Parental weighting of seizure risks vs. fever risks in vaccination tradeoff decisions

As part of a survey of about vaccination beliefs, a nationally representative sample of parents of young children answered a series of tradeoff questions that asked them to choose between two vaccination approaches that differed in terms of risks of vaccine complications, number of injections, and/or vaccine effectiveness. Most parents were willing to have their children endure more injections, and many were willing to forgo disease protection, in order to reduce the rare chance of febrile seizures. Yet, most parents were unwilling to trade disease protection to reduce the risk of fever alone, even though this is correlated with the risk of febrile seizures. Vaccine risk communications need to address the heightened emotional weight that parents give to febrile seizure risk, even when the rarity of such events is explicit.

Hippocampal Formation Maldevelopment and Sudden Unexpected Death across the Pediatric Age Spectrum.

Sudden infant death syndrome (SIDS) and sudden unexplained death in childhood (SUDC) are defined as sudden death in a child remaining unexplained despite autopsy and death scene investigation. They are distinguished from each other by age criteria, i.e. with SIDS under 1 year and SUDC over 1 year. Our separate studies of SIDS and SUDC provide evidence of shared hippocampal abnormalities, specifically focal dentate bilamination, a lesion classically associated with temporal lobe epilepsy, across the 2 groups. In this study, we characterized the clinicopathologic features in a retrospective case series of 32 children with sudden death and hippocampal formation (HF) maldevelopment. The greatest frequency of deaths was between 3 weeks and 3 years (81%, 26/32). Dentate anomalies were found across the pediatric age spectrum, supporting a common vulnerability that defies the 1-year age cutoff between SIDS and SUDC. Twelve cases (38%) had seizures, including 7 only with febrile seizures. Subicular anomalies were found in cases over 1 year of age and were associated with increased risk of febrile seizures. Sudden death associated with HF maldevelopment reflects a complex interaction of intrinsic and extrinsic factors that lead to death at different pediatric ages, and may be analogous to sudden unexplained death in epilepsy.

Febrile Seizure Risk After Vaccination in Children 6 to 23 Months.

An increased risk of febrile seizure (FS) was identified with concomitant administration of trivalent inactivated influenza vaccine (IIV3) and pneumococcal conjugate vaccine (PCV) 13-valent during the 2010-2011 influenza season. Our objective was to determine whether concomitant administration of IIV3 with other vaccines affects the FS risk. We examined the risk of FS 0 to 1 day postvaccination for all routinely recommended vaccines among children aged 6 through 23 months during a period encompassing 5 influenza seasons (2006-2007 through 2010-2011). We used a population-based self-controlled risk interval analysis with a control interval of 14 to 20 days postvaccination. We used multivariable regression to control for receipt of concomitant vaccines and test for interaction between vaccines. Only PCV 7-valent had an independent FS risk (incidence rate ratio [IRR], 1.98; 95% confidence interval [CI], 1.00 to 3.91). IIV3 had no independent risk (IRR, 0.46; 95% CI, 0.21 to 1.02), but risk was increased when IIV3 was given with either PCV (IRR, 3.50; 95% CI, 1.13 to 10.85) or a diphtheria-tetanus-acellular-pertussis (DTaP)-containing vaccine (IRR, 3.50; 95% CI, 1.52 to 8.07). The maximum estimated absolute excess risk due to concomitant administration of IIV3, PCV, and DTaP-containing vaccines compared with administration on separate days was 30 FS per 100 000 persons vaccinated. The administration of IIV3 on the same day as either PCV or a DTaP-containing vaccine was associated with a greater risk of FS than when IIV3 was given on a separate day. The absolute risk of postvaccination FS with these vaccine combinations was small.

Small risk of febrile seizures in infants after co-vaccination

Small risk of febrile seizures in infants after co-vaccination

Neonatal hyperbilirubinemia and the risk of febrile seizures and childhood epilepsy

PurposeThe aim of the study was to estimate the association between newborn children treated with phototerapy for hyperbilirubinemia and the subsequent risk of febrile seizures or epilepsy in early childhood. MethodsWe conducted a follow-up study of singleton children (N=70 230) born between February 1998 and May 2003 from the Danish National Birth Cohort (DNBC). Information on exposure to phototherapy for hyperbilirubinemia was obtained from a questionnaire in the DNBC. Information on epilepsy and febrile seizures were obtained from the Danish National Hospital Registry (DNHR). Cox proportional hazard regression model was used to calculate hazard ratios (HRs) with 95% confidence intervals (CI). ResultsNewborns treated with phototherapy for hyperbilirubinemia had a higher risk of developing epilepsy in early childhood (HR: 1.66, 95% CI: 1.23–2.24) but not febrile seizures (HR: 1.04, 95% CI: 0.86–1.27). The increases risk of epilepsy were only present for boys (HR: 1.98, 95% CI: 1.40–2.78) not for girls (HR: 1.14, 95% CI: 0.64–2.02) ConclusionPhototherapy for hyperbilirubinemia in newborns was associated with an increased risk of epilepsy for males in early childhood. No excess risk was seen with febrile seizures.

Post licensure surveillance of influenza vaccines in the Vaccine Safety Datalink in the 2013-2014 and 2014-2015 seasons.

The changes in each year in influenza vaccine antigenic components as well as vaccine administration patterns may pose new risks of adverse events following immunization (AEs). To evaluate the safety of influenza vaccines annually administered to people ≥ 6 months, we conducted weekly post licensure surveillance for seven pre-specified adverse events following receipt of influenza vaccines during the 2013-2014 and 2014-2015 seasons in the Vaccine Safety Datalink (VSD). We used both a historically-controlled cohort design with the Poisson-based maximized sequential probability ratio test (maxSPRT) and a self-controlled risk interval (SCRI) design with the binomial-based maxSPRT. For each adverse event outcome, we defined the risk interval on the basis of biologic plausibility and prior literature. For the historical cohort design, numbers of expected adverse events were calculated from the prior seven seasons, adjusted for age and site. For the SCRI design, a comparison window was defined either before vaccination or after vaccination, depending on each specific outcome. An elevated risk of febrile seizures 0-1 days following trivalent inactivated influenza vaccine (IIV3) was identified in children aged 6-23 months during the 2014-2015 season using the SCRI design. We found the relative risk (RR) of febrile seizures following concomitant administration of IIV3 and PCV13 was 5.3 with a 95% CI 1.87-14.75. Without concomitant PCV 13 administration, the estimated risk decreased and was no longer statistically significant (RR: 1.4; CI: 0.54 - 3.61). No increased risks, other than for febrile seizures, were identified in influenza vaccine safety surveillance during 2013-2014 and 2014-2015 seasons in the VSD. Copyright © 2016 John Wiley & Sons, Ltd.

Evaluating efficiency and statistical power of self-controlled case series and self-controlled risk interval designs in vaccine safety

ABSTRACTThe self-controlled case series (SCCS) and self-controlled risk interval (SCRI) designs have recently become widely used in the field of post-licensure vaccine safety monitoring to detect potential elevated risks of adverse events following vaccinations. The SCRI design can be viewed as a subset of the SCCS method in that a reduced comparison time window is used for the analysis. Compared to the SCCS method, the SCRI design has less statistical power due to fewer events occurring in the shorter control interval. In this study, we derived the asymptotic relative efficiency (ARE) between these two methods to quantify this loss in power in the SCRI design. The equation is formulated as (a: control window-length ratio between SCRI and SCCS designs; b: ratio of risk window length and control window length in the SCCS design; and : relative risk of exposed window to control window). According to this equation, the relative efficiency declines as the ratio of control-period length between SCRI and SCCS methods decreases, or with an increase in the relative risk . We provide an example utilizing data from the Vaccine Safety Datalink (VSD) to study the potential elevated risk of febrile seizure following seasonal influenza vaccine in the 2010–2011 season.

Febrile seizures after 2009 influenza A (H1N1) vaccination and infection: a nationwide registry-based study.

BackgroundDuring the 2009 influenza A (H1N1) pandemic, a monovalent pandemic strain vaccine containing the oil-in-water adjuvant AS03 (Pandemrix®) was offered to the Norwegian population. The coverage among children reached 54 %. Our aim was to estimate the risk of febrile seizure in children after exposure to pandemic influenza vaccination or infection.MethodsThe study population comprised 226,889 children born 2006–2009 resident in Norway per October 1st, 2009. Febrile seizure episodes were defined by emergency hospital admissions / emergency outpatient hospital care with International Classification of Diseases, Version 10, codes R56.0 or R56.8. The self-controlled case series method was applied to estimate incidence rate ratios (IRRs) in pre-defined risk periods compared to the background period. The total observation window was ± 180 days from exposure day. Among 113,068 vaccinated children, 656 (0.6 %) had at least one febrile seizure episode.ResultsThe IRR of febrile seizures 1–3 days after vaccination was 2.00 (95 % confidence interval [CI]: 1.15–3.51). In the period 4–7 days after vaccination, no increased risk was observed. Among the 8172 children diagnosed with pandemic influenza, 84 (1.0 %) had at least one febrile seizure episode. The IRR of febrile seizures on the same day as a diagnosis of influenza was 116.70 (95 % CI: 62.81–216.90). In the period 1–3 days after a diagnosis of influenza, a tenfold increased risk was observed (IRR 10.12, 95 % CI: 3.82 – 26.82).ConclusionsIn this large population-based study with precise timing of exposures and outcomes, we found a twofold increased risk of febrile seizures 1–3 days after pandemic influenza vaccination. However, we found that pandemic influenza infection was associated with a much stronger increase in risk of febrile seizures.

Febrile Seizures After 2010-2011 Trivalent Inactivated Influenza Vaccine.

In the Post-Licensure Rapid Immunization Safety Monitoring Program, we examined risk of febrile seizures (FS) after trivalent inactivated influenza vaccine (TIV) and 13-valent pneumococcal conjugate vaccine (PCV13) during the 2010-2011 influenza season, adjusted for concomitant diphtheria tetanus acellular pertussis-containing vaccines (DTaP). Assuming children would receive both vaccines, we examined whether same-day TIV and PCV13 vaccination was associated with greater FS risk when compared with separate-day vaccination. We used a self-controlled risk interval design, comparing the FS rate in a risk interval (0-1 days) versus control interval (14-20 days). Vaccinations were identified in claims and immunization registry data. FS were confirmed with medical records. No statistically significant TIV-FS associations were found in unadjusted or adjusted models (incidence rate ratio [IRR] adjusted for age, seasonality, and concomitant PCV13 and DTaP: 1.36, 95% confidence interval [CI] 0.78 to 2.39). Adjusted for age and seasonality, PCV13 was significantly associated with FS (IRR 1.74, 95% CI 1.06 to 2.86), but not when further adjusting for concomitant TIV and DTaP (IRR 1.61, 95% CI 0.91 to 2.82). Same-day TIV and PCV13 vaccination was not associated with excess risk of FS when compared with separate-day vaccination (1.08 fewer FS per 100 000 with same day administration, 95% CI -5.68 to 6.09). No statistically significant increased risk of FS was found for 2010-2011 TIV or PCV13, when adjusting for concomitant vaccines. Same-day TIV and PCV13 vaccination was not associated with more FS compared with separate-day vaccination.

Association between iron deficiency and febrile seizures.

The relationship between iron status and febrile seizures has been examined in various settings, mainly in the Developing World, with conflicting results. The aim of this study was to investigate any association between iron deficiency and febrile seizures (FS) in European children aged 6-60 months. Prospective, case-control study. Greek population in Thessaloniki. 50 patients with febrile seizures (cases) and 50 controls (children presenting with fever, without seizures). None. Haematologic parameters (haemoglobin concentration, haematocrit, mean corpuscular volume, red cell distribution width), plasma iron, total iron-binding capacity, plasma ferritin, transferrin saturation and soluble transferrin receptors were compared in cases and controls. Plasma ferritin was lower (median [range]: 42.8 (3-285.7) vs 58.3 (21.4-195.3ng/ml; p=0.02) and Total Iron Binding Capacity (TIBC) higher (mean [Standard Deviation] 267 [58.9] vs 243 [58.45] μg/dl, p=0.04) in cases than in controls. Results were similar for 12 complex FS cases (ferritin 30 (3-121 vs 89 (41.8-141.5ng/lL; TIBC 292.92 [68.0] vs 232.08 [36.27] μg/dL). Iron deficiency, defined as ferritin <30ng/ml, was more frequent in cases (24%) than controls (4%; p=0.004). Ferritin was lower and TIBC higher in 18 with previous seizures than in 32 with a first seizure although haemoglobin and mean cell haemoglobin concentration were higher. European children with febrile seizures have lower Ferritin than those with fever alone, and iron deficiency, but not anaemia, is associated with recurrence. Iron status screening should be considered as routine for children presenting with or at high risk for febrile seizures.

Association of genetic polymorphism of pre-microRNA-146a rs2910164 and serum high-mobility group box 1 with febrile seizures in Egyptian children.

Interaction between immune-inflammatory process and genetic factors might be implicated in the pathogenesis of febrile seizures. Pre-microRNA (miR)-146a rs2910164 polymorphism is postulated to modulate expression of miR-146a whose anti-inflammatory role involves regulation of high-mobility group box 1. Our aim is to examine whether rs2910164 polymorphism influences serum high-mobility group box 1 levels and whether an association exists between both and febrile seizures. The study included 136 children, divided into 4 groups. Real-time polymerase chain reaction was used for detection of rs2910164 polymorphism and high-mobility group box 1 was measured using enzyme-linked immunosorbent assay. High-mobility group box 1 levels were higher in febrile seizure patients compared to the other groups. Rs2910164 polymorphism was not associated with increased risk of febrile seizures. Rs2910164 polymorphism might be accompanied by an upregulation of the proinflammatory process as it might be associated with an increase in high-mobility group box 1 and leukocytic count.