How do I know if my child has infantile spasms?
Neurologists believe that it is important to identify infantile spasms as early as possible, in order to try to minimise the damage that they cause. The difficulty is that while the myoclonic spasms are very characteristic, they may initially be very subtle and difficult to recognise.
A full myoclonic spasm (also called a myoclonic jerk, or an epileptic spasm) is the rapid contraction and extension of a muscle, causing a limb to jerk. Indeed, the word "myoclonic" means just that - mys is greek for muscle, and klonos is greek for turmoil. The spasm may range from the twitch of a single limb, to the full scale contraction of all four limbs (often called a salaam fit, because it looks as though the child is bowing in greeting). The spasms often occur in clusters, with one or two every second.
The initial manifestation may just be a minor twitch of a single limb or eye. However, there are often associated symptoms. Many children who develop infantile spasms also have feeding difficulties and develop reflux. Arching backwards while feeding is an indicator for infantile spasms. Many children who develop infantile spasms also have sight difficulties, and failure to focus and track visually is another indicator.
Neurologists seem to distinguish three types of myoclonic episodes, because the underlying neural events are somewhat different, although the physical consequences are very similar:
The point is that very much the same physical manifestation - the myoclonic spasm - can have very different consequences, depending on its neurological correlates.
The most characteristic infantile spasm is the salaam fit. In this, all four limbs (and the head) contract simultaneously, causing the child to make a salaam (bow). The contraction is rapid, but usually only lasts for part of a second. The contractions usually occur in clusters of 5 to 10 with a spasm every second or so. Sometimes the clusters may be extended containing as many as 50 spasms. Sometimes the child will go floppy after the cluster.
Most other forms of myoclonic spasm are similar, but involve fewer muscles, perhaps just the arms, or the legs (the spasms are usually symmetric), or the head or abdominal muscles. The spasms may range from a massive contraction to a minor twitch.
As well as contractions, there may be extension, with the body arching and becoming rigid for a few moments.
The spasms may occur during sleep or when awake, but tend to develop when drowsy, or immediately on awakening. A cluster of fits may be preceded or followed by a cry. Sometimes the child is distressed afterwards, sometimes it may smile.
While myoclonic spasms occur in a wide variety, usually each child will just exhibit one type of spasm, although this may change slowly over a period of time.
If the child is at risk of having infantile spasms, for example because of hypoxia (lack of oxygen) at birth (the biggest single cause of infantile spasms), it is important to watch carefully for tell tale signs. Unfortunately, many doctors fail to recognise the early stages of infantile spasms, because the condition is rare (there are between 100 and 200 cases a year in the UK), and so the condition is often misdiagnosed as colic.
The important thing, if any symptoms are observed, is to be very concerned. The myoclonic spasm is often only a trivial physical event, but may indicate a serious neurological condition requiring urgent treatment. If you think a baby might have myoclonic spasms, then you should consult a good neurologist as soon as possible.
continue to Medical information
return to Infantile spasms
(checked: 15 November 2002)
(update 1.1: 8 November 2002)
(issue 1: 12 January 1998)