If any distinction at all be made, it should be one founded upon the fact that epilepsy itself is usually an organic disease, or, more precisely, a disease which when established is dependent upon some disorganization, while eclampsia is used to express those seizures of a purely functional nature.
By far the greater number of eclamptic seizures are found among young children. There is no uniformity in their expression or return. Any eccentric irritation is apt to precipitate one or more attacks, and those forms of irritation dependent upon sensory disturbances of the mucous membrane are commonly present. The convulsions of teething belong to this class, as well as those in which gastric disorder plays a part; and in the first instance the cutting of the large teeth, and in the latter the presence of indigestion with diarrhœa, are quite commonly associated with the convulsion.
The high degree of irritability of the nervous system of children renders them peculiarly susceptible to causes which in after years would effect little or no disturbance; and this is especially true before the fifth year. West and Reynolds are of the opinion that convulsions occur in children as delirium in adults; in other words, they are the most common expression of neurotic instability.
Infantile convulsions are usually general, and neuro-spasms are not common, except when they are dependent upon neoplasm, ventricular dilatation, or local meningitis. It evidently takes very limited peripheral excitement to precipitate a general convulsion in the child, and a familiar example is the disturbance which may involve the peripheral branches of the fifth nerve in difficult dentition.
Eclamptic seizures occur at any time, and may be very slight: a trifling twitching may be all, or, on the other hand, the attack may consist of violent opisthotonos. There is great difficulty, of course, in getting anything from a young child as to its feelings before an attack, and I hardly think we are authorized in saying that there is any aura or ascertainable precursor. The history of a previous nervous state is, however, usually ascertainable, which is expressed by crying fits, peevishness, and great restlessness. Sometimes there is a disposition to sleep which almost amounts to stupor. The behavior of a child is often likened to that which marks the commencement of acute tubercular meningitis—night-terrors, grinding of the teeth, and flushing of the face. The first convulsions may be only partial, but in a short time their character becomes general, and they become exceedingly violent, and are sometimes fatal. The clinical features of an eclamptic seizure may in every respect resemble one of epilepsy, making allowance for the age of our patient.
The stage of pallor is perhaps more extended in the child.
Handfield Jones speaks of a form of eclampsia of hyperæmic causation in association with certain exanthemata. In children convalescing from scarlatina he observed the development of attacks which were relieved by carotid pressure and bleeding in subjects who presented anasarca and other indications of renal disease.
We are familiar enough with the convulsions of puerperal women, which, as a rule, though not always, are presented by subjects whose urine is albuminous. It can sometimes distinctly be traced to what must be regarded as uterine excitement. Just as chorea is often a feature of the pregnant state, so may convulsive seizures arise. The peculiarities of the epilepsy of pregnancy will, however, be elsewhere considered.
I shall purposely refrain from the consideration of those forms of symptomatic infantile convulsions which mark the occurrence of cerebral accidents or grave disease.