Medical Treatment

The observable ‘clinical’ seizures which do NOT appear to correlate with severity of the developmental impairment
The electrical seizure activity that occurs in sleep and is thought to cause the regression

Anticonvulsants are drugs that are used to stop seizures. They are usually very effective for the visible seizures but their effect on the sub-clinical seizure activity, which is characteristic of LKS and typically occurs in sleep, is often disappointing. Some children may respond to conventional anticonvulsants, and it is well recognised that high dose benzodiazepines (for example, clobazam taken usually at night) can be particularly effective. Sodium valproate is also commonly used and occasionally other antiepileptic drugs appear to be effective.

Corticosteroid drugs can be dramatically effective in stopping seizures and reversing a child’s losses. They are either used in short high-dose courses or in prolonged weekly (pulsed) courses with careful monitoring of side effects. Some children recover well with a single short course (steroid-responsive), others make good recovery but lose skills when steroids are stopped (these children are steroid-dependent and may respond to longer-term weekly steroids). Others have only partial or no response. The most complete steroid responses appear to be seen in children whose regression is largely limited to inability to understand speech (that is, pure auditory agnosia) and who do not have additional impairments in behaviour, social communication, cognition etc.

As with all treatments, it is important to consider the benefits and risks involved, and to be clear about the aims. LKS is notoriously difficult to treat, so it is important to have evidence of a treatment’s effectiveness, before subjecting a child to prolonged medication. Specialist assessment by a speech and language therapist, before and after starting treatment is very helpful in documenting changes in skills and judging effectiveness. Baseline assessment of cognitive skills is also very useful in determining the overall learning profile and identifying strengths and weaknesses.

All drugs have side effects and it is necessary to monitor for these (for example, steroids – sugar in urine, blood pressure). Steroids, in particular, are powerful drugs that when given in high dose on a daily basis can affect a child’s growth, bone strength, ability to fight infection and lead to diabetes, high blood pressure and even stomach ulcers. This is why daily steroids are usually restricted to a short period (such as six to twelve weeks). Weekly pulsed steroids appear to allow the medical benefit, without the same side effects. However, chickenpox is a serious illness if a child catches it whilst on any form of steroids and it is important to discuss this with your doctor if your child has not had this infection.

Many parents worry about the effects that drugs have on learning but this is rarely a problem. It is the subclinical seizure activity that has the major impact on learning, and generally, drugs that control this activity enable learning to take place without ongoing interference from seizure activity.

Some parents also express concerns about the possible behavioural effects of drugs (for example, drowsiness, overactivity, changed appetite, insomnia, bedwetting). This can be a problem, and children with LKS appear particularly vulnerable to some side effects such as irritability with sodium valproate, or sleeping problems with lamotrigine. It is often hard to disentangle these from the behavioural difficulties commonly seen in children with LKS. For example, it is not unusual for parents to describe increased aggression and hyperactivity associated with the early phase of steroids – although equally, many parents report dramatic improvement in their child’s behaviour on steroids as the disease comes under control. Specific concerns should be discussed with the local team managing the child.

It is important to realise that all drugs have two names, as this can be confusing. There is the generic name (main chemical the medicine is made from) and the trade name (used by the company which produces the drug). For example, sodium valproate is the generic name and Epilim® is the trade name. It can be difficult to persuade children to take medication and different formulations such as syrup or sprinkles may be helpful.

There are also occasional anecdotal reports of benefits from other treatments such as immunoglobulins or a ketogenic diet.