West syndrome is a rare and serious form of epilepsy that usually affects babies under the age of one year. Also known as infantile spasms (and a variety of other names including Generalised Flexion Epilepsy), it affects about 1 in 5,000 babies and accounts for about one in 20 cases of childhood epilepsy.

West syndrome actually describes a collection of problems – infantile spasms, a specific pattern on an EEG test of electrical activity in the brain, developmental regression and often learning disability – which occur as a result of one of a variety of possible causes. In about 70 to 80 per cent of cases the cause can be identified, such as birth trauma and starvation of oxygen from the baby's brain, or a condition known as tuberose sclerosis.

Unfortunately, the long-term prognosis is very poor, although this depends to some extent on the underlying cause and whether this is a progressive disease.

Begins in early childhood

West syndrome usually becomes apparent at the age of about four to six months, when the child first has a brief spasm in which their body may bend forwards (known as a 'salaam attack' because it's as if the baby is bowing), arch backwards (an extensor spasm) or both.

The whole body or limbs may be affected but sometimes just the head and eyes are involved. The spasms occur principally on waking.

Because there are often multiple spasms, as many as a 100 in rapid succession, the child is left exhausted and upset.

Not long after the spasms have started, the baby's ability to interact socially through means such as eye contact, smiling and cooing is lost. Visual awareness is also lost, with irreversible visual damage, and developmental delays become apparent, which may be severe.

Treatment options

Anti-epilepsy drugs may help to control seizures. A drug called vigabatrin, for example, abolishes spasms in up to 50 per cent of babies and is especially effective when the underlying cause is tuberose sclerosis. However, the risks and side effects - especially in the long term - aren't clear.

Steroids and other drugs may be used too, but in many cases the drugs must be stopped or the spasms return.

Sadly, long-term control of seizures and maintenance of normal brain function is achieved in fewer than 15 per cent of affected children.

Some children progress to another particularly severe epileptic syndrome called Lennix-Gastaut syndrome (LGS).

As with all disabling childhood diseases, educational therapies and family support play a central part in helping a child with West syndrome to enjoy a good quality of life and develop their potential as far as possible.

This article was last medically reviewed by Dr Trisha Macnair in September 2008