In diagnosing febrile seizures, your GP will want to identify the source of the infection. They will also want to rule out rarer conditions, such as meningitis (a brain infection), which can cause similar symptoms.
Urine and blood tests
Your GP may want to run a series of tests, such as blood or urine tests, to check for the signs of infection. Sometimes it is difficult to obtain a urine sample from young children, so it may have to be done in hospital.
Further tests
Further tests may be carried out in hospital if your child’s symptoms are unusual – for example, if they do not have a high temperature or their seizures do not follow the normal pattern. Further testing and observation in hospital is also usually recommended if your child is having complex febrile seizures (see Febrile seizures - introduction).
Your child may have other tests, including:
- an electroencephalogram
- lumbar puncture (particularly if your child is less than 12 months old)
These are briefly explained below.
Electroencephalogram
An electroencephalogram (EEG) measures the electrical activity of your child’s brain through electrodes that are placed on their scalp. Unusual patterns of brain activity can sometimes indicate epilepsy.
See the Health A-Z topic about Electroencephalogram for more information about the procedure.
Lumbar puncture
During a lumbar puncture, a small sample of cerebrospinal fluid (CSF) is removed for testing. CSF is a clear fluid that surrounds and protects the brain and spinal cord.
The sample of CSF is obtained by placing a hollow needle into the base of your child’s spine and drawing out a few millimetres of fluid. During the procedure, local anaesthetic will be used to numb your child’s back so that they feel no pain.
A lumbar puncture is an effective method of determining whether your child has an infection of the brain or nervous system.
See the Health A-Z topic about Lumbar puncture for more information about the procedure.
