Toxicological Screening by GC-MS Among Children Admitted for a First Afebrile Seizure
Condition: Afebrile Seizure (Finding)
MeSH terms: Seizures
Study type: Interventional

Summary: 
      Before the age of 14 years, 1% of the paediatric population will develop a seizure. The only
      systematically required complementary examination is an electroencephalogram (EEG).
      Additional biological or radiological examinations depend on the circumstances, the past
      medical history of the patient and other associated symptoms or clinical signs. A seizure can
      be the first sign of acute intoxication and represents a severity criterion. Failure to
      detect the toxic cause of a seizure can lead to a delay in the access or administration of an
      antidote if applicable. This can lead to target organ toxicity due to the absence of specific
      treatment. In the current French guidelines for a first seizure, a toxicological analysis is
      recommended if there is a possibility of exposure to toxic medications or products. However,
      this screening is often missing, unless a witness suggests that the child may have been
      exposed to a toxin.The recognition of a paediatric toxidrome is low among paediatricians,
      paediatric neurologists or emergency physicians. This is due to a lack of knowledge in
      clinical toxicology and the screening for toxic aetiology is not frequently or irrelevantly
      prescribed. There is an increasing number of proconvulsive molecules on the market. These
      molecules are not targeted in classic toxic screening. As result, a toxic cause of a seizure
      may be missed unless specific screening is performed. For all these reasons, little is known
      about the prevalence of toxic causes after a first episode of non-febrile seizure and
      probably under estimated in the paediatric population, especially in young children. New
      technologies for toxic detection like chromatography combined with mass spectrometry allow
      wide screening on different matrix. Initially dedicated to forensic analysis, they are more
      widely accessible for the exploration of the patients. The CASTox study is based on this
      context.

      The first aim will be to evaluate the prevalence of a toxicological cause by a systematic
      blood and urine screening of children admitted to Toulouse paediatric emergency unit for a
      first afebrile seizure. Moreover, secondary aim will be to describe the effect of the
      systematic screening on the management of the children.
    

Detailed description: 
      Before the age of 14 years, 1% of the paediatric population will develop a seizure. The only
      systematically required complementary examination is an electroencephalogram (EEG).
      Additional biological or radiological examinations depend on the circumstances, the past
      medical history of the patient and other associated symptoms or clinical signs. A seizure can
      be the first sign of acute intoxication and represents a severity criterion. Failure to
      detect the toxic cause of a seizure can lead to a delay in the access or administration of an
      antidote if applicable. This can lead to target organ toxicity due to the absence of specific
      treatment. In the current French guidelines for a first seizure, a toxicological analysis is
      recommended if there is a possibility of exposure to toxic medications or products. However,
      this screening is often missing, unless a witness suggests that the child may have been
      exposed to a toxin.The recognition of a paediatric toxidrome is low among paediatricians,
      paediatric neurologists or emergency physicians. Since the end of the 90s, the molecules
      usually incriminated with seizure onset after intoxication are: with a high risk (polycyclic
      antidepressant, theophylline, isoniazid); intermediate risk (fluoroquinolones, tramadol,
      lidocaine, lithium, anticonvulsive medications) and low risk (selective serotonin reuptake
      inhibitors). Among infants, the molecules are quite different mainly because of the
      unintentional or malicious aspect of the intoxication and are dominated by sympathomimetic
      agents, antihistamine drugs, anticholinergic molecules, antidepressants and muscle relaxants.
      New drugs have been associated with seizures in young intoxicated children like bupropion,
      tramadol and venlafaxine. These agents are not detected by usual toxic analysis.

      For each patient and after getting the signed consent form, a toxicological analysis will be
      performed on blood and urine samples to extensively screen for proconvulsive molecules
      (alcohols, polycyclic antidepressants, salicylates, anticonvulsive medications
      (carbamazepine, phenytoin, valproic acid), drugs (cocaine and its metabolites, amphetamines,
      methamphetamine (ecstasy), cannabis, buprenorphine, methadone, mephedrone, codeine,
      pholcodine, hydromorphone), benzodiazepines, caffeine, theophylline, lidocaine, isoniazid,
      mefenamic acid, tramadol, ephedrine).

      This analysis will be performed using classic approach (immunoenzymatic detection) and by
      chromatography (GC) associated to mass spectrometry (MS) (Laboratory of Toxicology,
      University Hospital of Toulouse) - The other clinical data, biological results or tests
      requested by the physician in charge will be reported from the computerized medical file of
      each patient.

      For each patient hospitalized, a follow-up visit will be scheduled during hospitalization in
      order to report management of the children.
    

Intervention name(s): Collection of blood and urine samples; Clinical examination
Intervention type(s): Other; Other
Intervention description(s): For each child, a toxicological screening will be carried out on the blood and urine for the research of proconvulsive molecules by conventional technique on the one hand and by gas chromatography coupled with a mass spectrograph on the other hand.; The other clinical data, any other biological samples or additional examinations are done under the opinion of the clinician or the neuropediatrics.
Intervention model: Single Group Assignment
Intervention model description: Transverse prevalence study. For each child, a toxicological screening will be carried out on the blood and urine for the research of proconvulsive molecules by conventional technique on the one hand and by gas chromatography coupled with a mass spectrograph on the other hand.
Masking: None (Open Label)
Primary purpose: Screening
Keywords: Afebrile seizure; Toxicological screening; Chromatography; Mass spectrometry; Children