epilepsy in pregnancy

Question 1

What is the incidence of epilepsy amongst women of child bearing age?

Answer 1

1:200 or 0.5%

Most common neurological condition in pregnancy

Question 2

What are the two causes of epilepsy?

Answer 2

Primary/idiopathic - 30%

Secondary - previous surgery or irradiation, space occupying lesion, Antiphospholipid syndrome

Question 3

What are the 7 differential diagnoses of seizures in pregnancy

Answer 3

Eclampsia
Vascular 
Infection
Metabolic
Drug and alcohol related
Post dural puncture
Pseudo seizure

Question 4

List 3 examples of metabolic causes of seizure activity?

Answer 4

• Hypoglycaemia
• Hypocalcemia
• Hyponatraemia

Question 5

List 4 vascular causes of seizure activity in pregnancy

-

Answer 5

• central vein thrombosis
• thrombotic thrombocytopenia purpura
• stroke (4%)
• subarachnoid haemorrhage

Question 6

What investigations do you need to perform for seizure in pregnancy?

Answer 6

Bloods - FBC, LFT, Coags, Extended electrolyte panel, U&E, TFTs, Glucose
Urinalysis - toxicology (also ruling out proteinuria/PET)
Imaging - CT or MRI

Question 7

What percentage of women with epilepsy will have a seizure in labour?

Answer 7

3.5%

Question 8

What 4 fetal anomalies can occur with anti epileptic drugs?

Answer 8

• Neural tube defects
• orofacial clefts
• cardiovascular defects
• urogenital defects

Question 9

What is fetal AED syndrome?

Answer 9

Dysmorphic features
Hypertelorism
Hypoplastic nails and digits
Hypoplasia of mid face

Question 10

List 5 predictors of SUDEP? (sudden unexpected death epilepsy)

Answer 10

Generalised tonic clonic epilepsy
uncontrolled or poorly controlled generalised tonic clonic epilepsy
nocturnal GTCE
living or sleeping alone with GTCE
polytherapy

Question 11

what are the principles of treating a patient with epilepsy

Answer 11

• do not stop AED
• minimise seizure triggers
• avoid medicines that lower seizure threshold (amitriptyline, tramadol, pethidine)

Question 12

what do the RCOG and NICE guidelines recommend regarding drug monitoring with AED?

Answer 12

• do not routinely monitor
• EMPiRE trial showed that there was no evidence to suggest that routine monitoring of AED actually makes a difference to maternal or fetal outcomes, or improves seizure outcomes

Question 13

What is the theoretical effect of physiology of pregnancy with regard to lamotrigine?

Answer 13

lamotrigine is metabolised by liver glucoronidation
this is upregulated in pregnancy
therefore could imagine that lamotrigine dosing may need to go up during pregnancy

Question 14

Based on the physiology of pregnancy what monitoring would you provide for patient on lamotrigine

Answer 14

Metabolised by liver glucoronidation which increases inpregnancy
therefore trimester assessment of levels if stable otherwise monthly
consider post partum assessment if have increased dose during pregnancy

Question 15

How would you expect the physiology of pregnancy to impact on levetiracetam levels?

Answer 15

• renally excreted
• therefore increased clearance in pregnancy
• therefore may need higher doses to achieve same effect in pregnancy

Question 16

Which AEDs are most associated with fetal anomaly in pregnancy?

Answer 16

valproate
carbamazepine
phenobarbitol
phenytoin