An observational study in Febrile Convulsion, Neuroendocrine Stress Response and Fever, sponsored by Aydin Adnan Menderes University. Not yet recruiting at 1 site in Turkey (Türkiye). Open to participants aged 6 Months to 5 Years. Per ClinicalTrials.gov, last updated 2026-03-11.
Sponsored by Aydin Adnan Menderes University · Observational
Febrile seizures are the most common seizure type in early childhood and usually occur during febrile illnesses. Although most febrile seizures are benign, the biological stress response during seizures is not fully understood. In particular, changes in thyroid hormones and stress-related hormones released by the sympathetic nervous system may play a role in seizure characteristics and clinical outcomes.
This prospective observational study aims to evaluate the neuroendocrine response in children presenting with febrile seizures by measuring serum thyroxine (T4), epinephrine, and norepinephrine levels. These measurements will be obtained during the acute phase after seizure cessation and compared with levels measured at recovery and with febrile children without seizures.
The study will examine the relationship between neuroendocrine marker levels and seizure characteristics such as seizure duration and recurrence, as well as clinical outcomes including length of hospital stay and need for pediatric intensive care unit admission.
By improving understanding of the hormonal stress response associated with febrile seizures, this study aims to contribute to the knowledge of seizure pathophysiology in childhood and may help identify biological factors associated with more severe clinical courses.
Febrile seizures represent a common pediatric neurological emergency and are triggered by fever-related systemic stress rather than primary epileptic pathology. Acute febrile seizures are accompanied by activation of the hypothalamic-pituitary-thyroid axis and the sympathetic-adrenal system, resulting in measurable changes in circulating thyroid hormones and catecholamines. However, the magnitude and clinical relevance of this neuroendocrine response remain incompletely characterized.
This study is designed as a prospective, observational, case-control investigation conducted in a pediatric emergency department setting. Children aged 6 months to 5 years presenting with febrile seizures will be enrolled as the case group. An age-matched control group will consist of febrile children without seizures. Participants will not be assigned to any intervention, and all clinical management will follow standard care practices.
In the febrile seizure group, blood samples for measurement of serum thyroxine (T4), epinephrine, and norepinephrine will be obtained within 30 minutes after seizure cessation to capture the acute neuroendocrine stress response. Additional samples will be collected prior to hospital discharge to assess recovery-phase hormone levels. In the control group, blood samples will be collected during the febrile episode at the time of clinical evaluation. All laboratory analyses will be performed using validated methods under standardized conditions.
Clinical data collected will include demographic characteristics, fever features, seizure type and duration, recurrence during hospitalization, treatment administered, length of hospital stay, and requirement for pediatric intensive care unit admission. The primary objective is to evaluate associations between acute-phase neuroendocrine marker levels and seizure characteristics, particularly seizure duration and recurrence. Secondary objectives include comparisons between febrile seizure patients and febrile controls, as well as associations between hormone levels and clinical outcomes.
Statistical analyses will include descriptive methods, group comparisons using parametric or nonparametric tests as appropriate, correlation analyses, and multivariable regression models adjusting for relevant confounders such as age, sex, peak temperature, seizure type, and treatment exposure. The study aims to provide mechanistic insight into the neuroendocrine stress response associated with febrile seizures and to explore its potential relationship with disease severity and short-term outcomes.
24 studies on the registry are indexed under Seizures, Febrile; 2 are open to participants now.
This study's planned enrollment of 120 is below the median of 136 across 14 observational studies indexed under Seizures, Febrile.
Browse Seizures, Febrile studies →Aydin Adnan Menderes University is the lead sponsor of 241 studies on the registry; 51 are open to participants now.
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The study population includes children aged 6 months to 5 years presenting with febrile seizures and an age-matched febrile control group without seizures, enrolled prospectively in a pediatric emergency department. The study evaluates differences in acute neuroendocrine hormone levels (thyroxine [T4], epinephrine, and norepinephrine) and their associations with seizure characteristics and short-term hospital outcomes.
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Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Children aged 6 months to 5 years presenting with febrile seizures who are enrolled prospectively. Blood samples are obtained within 30 minutes after seizure cessation to assess acute neuroendocrine response, including thyroxine (T4), epinephrine, and norepinephrine levels. Additional samples are collected prior to hospital discharge. Clinical data including seizure characteristics, recurrence, length of hospital stay, and need for pediatric intensive care unit admission are recorded. No experimental intervention is administered.
Age-matched febrile children without seizures enrolled as the control cohort. Blood samples are obtained during the febrile episode to measure thyroxine (T4), epinephrine, and norepinephrine levels. Clinical data related to fever characteristics are collected for comparison with the febrile seizure cohort. No experimental intervention is administered.
Difference in acute neuroendocrine hormone levels between febrile seizure patients and febrile controls
The difference in serum thyroxine (T4), epinephrine, and norepinephrine levels measured during the acute phase between children presenting with febrile seizures and age-matched febrile children without seizures.
Time frame: Baseline (during the emergency department presentation)
Association between neuroendocrine hormone levels and seizure duration
The association between acute-phase serum thyroxine (T4), epinephrine, and norepinephrine levels and seizure duration (in minutes) in children presenting with febrile seizures.
Time frame: Baseline (during the index febrile seizure event)
Association between neuroendocrine hormone levels and hospital length of stay
The association between acute-phase serum thyroxine (T4), epinephrine, and norepinephrine levels and total hospital length of stay in children presenting with febrile seizures.
Time frame: From hospital admission through discharge (up to 7 days)
Association between neuroendocrine hormone levels and pediatric intensive care unit admission
The association between acute-phase serum thyroxine (T4), epinephrine, and norepinephrine levels and the requirement for pediatric intensive care unit (PICU) admission in children presenting with febrile seizures.
Time frame: During the index hospitalization (up to 7 days)
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
Start is estimated for Mar 2026; primary completion for Mar 2027, 12 months later.
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