Febrile Convulsion

Question 1

A febrile convulsion is a seizure due to a raised temperature. What is the incidence of these?

1 - 2100 cases per 100,000
2 - 210 cases per 100,000
3 - 21 cases per 100,000
4 - 2.1 cases per 100,000

Answer 1

1 - 2100 cases per 100,000

Affects boys and girls equally

VERY COMMON

Question 2

A febrile convulsion is a seizure due to a raised temperature. What age does the incidence typically peak at?

1 - 0-12 months
2 - 1-5 years
3 - 5-10 years
4 - 10-20 years

Answer 2

3 - 5-10 years

Question 3

Febrile convulsions can be caused by all of the following, but which of the following accounts for 80% of cases?

1 - Respiratory tract infections
2 - Otitis media
3 - Urinary tract infections
4 - Influenza
5 - Viral infection
6 - Vaccination

Answer 3

5 - Viral infection

Strong link with Human herpes virus 6 (HHV-6) specifically

Vaccination - this is rare, occurring 1-2 weeks after, but benefits of vaccination outweighs the risks

Question 4

Is there an increase risk of febrile convulsion in premature babies?

Answer 4

• yes

Question 5

Typically, 75% of patients present with which type of seizure?

1 - generalised tonic-clonic
2 - absent seizure
3 - partial simple tonic-clonic
4 - partial complex absent

Answer 5

3 - partial simple tonic-clonic

Partial = small part of brain affected
Simple = specific to one region of the brain and doesn’t spread
Tonic = stiffness/tension in muscles
Clonic = repeated jerking limb movements

Question 6

Although 75% of patients present with a partial simple tonic-clonic seizure, they can also have a complex febrile convulsions. Do these last longer or shorter than partial simple tonic-clonic seizures?

Answer 6

• typically last longer

Present similarly but with more focal features, such as movement limited to only one side of the body. These last longer than 15 minutes and recur within 24 hours or within the same illness, unlike simple convulsions. The post-ictal period is often prolonged compared with simple convulsions.

Question 7

Although 75% of patients present with a partial simple tonic-clonic seizure, they can also have a complex febrile convulsions. What of the following would make you think complex febrile convulsions over a partial simple tonic-clonic seizure?

1 - focal features, such as movement limited to only one side of the body
2 - last shorter
3 - always occur at peak temperature
4 - shorter post-ictal period

Answer 7

1 - focal features, such as movement limited to only one side of the body

• typically seizures last longer
• typically post-ictal phase is longer
• not associated with peak temperature

Question 8

In febrile convulsions, children typically present with a partial simple tonic-clonic seizure without focal features (not isolated to a specific body part). They can also present with all of the following, EXCEPT which one?

1 - Breathing difficulties
2 - Pallor
3 - Arrhythmias
4 - Cyanosis
5 - Loss of consciousness

Answer 8

3 - Arrhythmias

Question 9

In febrile convulsions, children typically present with a partial simple tonic-clonic seizure without focal features (not isolated to a specific body part). This can cause post-ictal drowsiness and confusion. How long before the children have recovered completely?

1 - <5 minutes
2 - <10 minutes
3 - <30 minutes
4 - <1 hour

Answer 9

4 - <1 hour

Question 10

How long must a seizure last to be defined as febrile status epilepticus?

1 - >5 minutes
2 - >10 minutes
3 - >30 minutes
4 - >1 hour

Answer 10

3 - >30 minutes

Medical emergency and needs to be stopped!

Question 11

Do febrile convulsions always occur at the peak temperature?

Answer 11

• no

Typically occur within the first 24 hours of a febrile illness.

Not associated with peak temperature
Associated with sudden rise in temperature

Question 12

Although all of the following are important, which of the following can help identify if this is a febrile or epileptic seizure?

1 - multiple previous seizures
2 - age at onset
3 - development history
4 - all of the above

Answer 12

1 - multiple previous seizures

Also important to ask about:

• recent immunisations
• presence and onset of fever
• peak temperature
• duration and character of seizure

Question 13

The diagnosis of a febrile convulsion is clinical. Which of the following examinations should be performed post seizure?

1 - cardiac exam
2 - cranial and peripheral nerve exam
3 - head MRI
4 - gastro exam

Answer 13

2 - cranial and peripheral nerve exam

Others may be performed, but this is most important to identify any focal neurological deficits

Question 14

The diagnosis of a febrile convulsion is clinical. However, which of the following can be useful if fever is likely cause?

1 - FBC
2 - U&E
3 - ESR
4 - coagulation
5 - glucose
6 - urine culture (<18 months of age or complex seizure)
7 - all of the above

Answer 14

7 - all of the above

Question 15

A lumbar puncture is important to consider to rule out meningitis,. What symptoms may a patient have that would increase the suspicion of meningitis?

1 - neck stiffness
2 - Kernig sign
3 - Brudzinski sign
4 - all of the above

Answer 15

4 - all of the above

Question 16

If the clinical diagnosis is unclear between a febrile convulsion or epilepsy, they may be invited back for which 2 of the following?

1 - lumbar puncture
2 - head MRI
3 - EEG
4 - ECG and echocardiogram

Answer 16

2 - head MRI
3 - EEG

Question 17

Which of the following is the LEAST likely differential diagnosis for febrile convulsions?

1 - Epileptic seizures
2 - Viral meningitis
3 - Bacterial meningitis
4 - Extradural haemorrhage
5 - Acute encephalopathy
6 - Dravet syndrome

Answer 17

4 - Extradural haemorrhage

Dravet syndrome is a severe form of epilepsy characterised by frequent, prolonged seizures often triggered by high body temperature (hyperthermia), developmental delay, speech impairment, ataxia, hypotonia, sleep disturbances, and other health problems.

Question 18

Although febrile convulsions need nothing more but A-E advice for the parents, which 2 of the following should be considered if a febrile convulsion lasts longer than 5 minutes?

1 - buccal midazolam
2 - rectal diazepam
3 - buccal levetiracetam
4 - IV sodium valproate

Answer 18

1 - buccal midazolam
2 - rectal diazepam

Both are benzodiazepines
Second dose can be given if seizure continues for >10 minutes

Question 19

Which of the following can be a scary complication of a febrile convulsion?

1 - syncope
2 - post-ictal confusion
3 - todd’s paresis
4 - nausea and vomiting

Answer 19

3 - todd’s paresis

• transient hemiparesis
• usually subsides completely within 48 hours.

Question 20

What % of patients with a febrile convulsion, go onto develop epilepsy?

1 - >75%
2 - 40%
3 - 10%
4 - 1%