commotion in the nervous system which goes by the name of eclamp sia, or a fit of convulsions, is a common phenomenon in infancy, and is sometimes seen in early childhood. The seizure depends upon an ex alted excitability of the reflex centres seated in the pops and medulla ob longata, but is seldom attended by changes in those parts capable of being detected on examination of the dead body. The disturbance is essentially a symptom, and may be produced by a variety of causes. Irrespective, then, of the immediate danger to life, the phenomenon may be of serious moment or of trifling consequence according to the cause which has in duced it. It is, therefore, of great importance to ascertain its mode of origin, for only by this means can we speak with any certainty as re gards the influence which the attack is likely to have upon the future well being of the child.
It is during the first two years of life that the tendency to this form of nervous derangement is most active. At this period of childhood the ner vous system of the infant, although immature, is undergoing rapid devel opment, and the reflex centres respond briskly to every form of peripheral irritation. The tendency to eclampsia is not, however, confined to this age. Convulsions may even affect the infant in the womb. Early death of the foetus and premature labour can be sometimes attributed to this cause, and it is to this accident that some varieties of congenital deformity have been referred—those which are characterised by permanent contrac tion of special muscles. After birth the proneness to convulsions may con tinue for a longer or shorter time, according to the natural sensitiveness of the nervous system to external impressions. It is therefore much more persistent in some children than in others, and may endure in exceptional cases to the ninth or tenth year.
are certain conditions which predispose a child to convulsions. Thus the liability to eclamptic seizures sometimes runs in families, so that all the children born of certain parents are found to suffer from these attacks. In other cases the tendency is confined to certain in dividuals of the family, or even to one sex. Thus• all the boys may have convulsions while the girls escape. Again, in rickets there is a special convulsive tendency which is very remarkable, and a large number of the cases of reflex convulsions are found to occur in children with this consti tutional condition. When the predisposition exists very slight causes— causes often so trifling as to escape recognition—may induce the attacks.
Within certain limits the state of a child's nutrition does not appear to affect his susceptibility to convulsive seizures. A strong child and a weak one may be equally prone to suffer from this nervous disturbance. When, however, an infant is greatly reduced by long-continued interference with. nutrition, a remarkable difference is noticed in his sensibility to nervous impressions. Not only is there no exaltation of reflex function, but the normal excitability of the reflex centres is diminished or annulled. There fore in a child so enfeebled convulsions are seldom of reflex origin, but usually indicate grave cerebral disease.
The exciting causes of the nervous commotion are very various : True reflex convulsions arise from peripheral irritation. Injuries to the skin from pricks, burns, and wounds ; irritation of the alimentary canal from indigestible food, hard faecal masses, or parasitic worms ; of the gums from inflammation and swelling during the cutting of a tooth ; of the ear from collections of wax, the presence of a foreign body in the auditory meatus, or inflammation of the tympanic cavity ; retention of urine ; sud den chilling of the surface from exposure ; violent emotions, such as ter ror—all these causes may set up convulsions in certain subjects.
Irritation affecting the mucous membrane of the stomach and intestine, and according to some authors irritation within the ear, seem to be the most common exciting causes of reflex convulsions. In hand-fed babies incligestion is a familiar occurrence, and the disturbance set up by a mass of undissolved curd or other irritant may speedily culminate in an attack of eclampsia. Again, otitis is a more common disease of infancy than is usually supposed. It is often a direct consequence of dental irritation, and occurs with such frequency as to constitute one of the more common complications of dentition. According to Dr. Woakes the inflamed and swollen grim is a: source from which irritation is conveyed to the otic ganglion, and thence is deflected to the vessel supplying the tympanic membrane. Acute congestion of the membrane thus occasioned is a source of extreme pain ; and if the irritation persist, suppuration in the tympanic cavity may follow. Inflammatory tension of the gum alone may set up the eclamptic attack ; and the secondary disturbance in the ear is a fruitful source of such seizures.