BENIGN NEONATAL CONVULSIONS
Several type of seizures can occur during the neonatal periode.
1. Focal Epilepsies
There is no Partial Idiopathic Epilepsy described in the neonatal period.
It is conceivable to have a localization related epilepsy secondary to a
focal lesion to have its onset in the neonatal period. However because at this
age the Seizures are often if not always, both focal and generalized, this
category is regrouped in 3.1.
2. Generalized Epilepsies
There are 2 syndromes described under the IGE which have their onset in
the neonatal period. These are:
2.1.2. Benign Neonatal Convulsions
Symptomatic or Cryptogenic.
The difference with 2.2 and 2.3 is that in these (2.3)syndromes
there is a definite lesion in all cases.
2.3.1. Without a specific aetiology. There are 2 syndromes described in
the neonatal age group.
126.96.36.199. Early Infantile Myoclonic Encephalopathy
( described by Aicardi )
188.8.131.52. Infantile Epileptic Encephalopathy of
2.3.2. With a specific aetiology. Here we find the Progressive myoclonic
epilepsies and in particular the early infantile form of the Ceroid
LipoFuscinosis: The Santavuori Syndrome.
3. Undetermined Epilepsies.
both partial and generalized Seizures.
This is where most of the neonatal seizures are going to enter. NB that
in this Category of epilepsies (3.) we have lost the previous way of
classification between Idiopathic and symptomatic. Therefore there will be both
type regrouped under the same heading. 2 main syndromes are described:
3.1.1. Neonatal Seizures without specific
aetiology or with specific aetiology. i.e.. the ones we see after perinatal anoxia
as well as the ones we do not know why they are there.
But are excluded the seizures in the context of an acute metabolic
4. Special Syndromes.
relation with a situation. We have here only the seizures in a metabolic
BENIGN NEONATAL SEIZURES
Also known as "5th day seizures".
to various studies prevalence varies between 4 and 38% of all NNS. It is more
likely to be closer to the lower number (4%) than to the upper one.
> females by 62% vs. 38%.
always between day 1 and day 7
day 4 and day 6
3 and day 7
all ALWAYS clonic, often partial, alternating and or apneic, NEVER tonic. Motor
seizures are often lateralised, going from one hemi body to the other, less
about 1 mn to 3 mn. They are often
repeated realizing a status epilepticus. The average length of this status is 20
hours, but can be shorter 92Hrs) or longer (3 days).
onset of the status the baby neurological exam is normal. Then the child becomes
drowsy, AED's? and hypotonic. Later the children recover a normal neurological status.
can be normal, discontinue, with focal or multifocal anomalies. But
most frequently: "theta pointu alternant".
Dominant Theta activity
Alternating or discontinue
Wake state as well as sleep (both slow and agitated)
status the "theta pointu alternant" can be found until day 12. It will
then be possible to diagnose Benign neonatal seizures outside of the status
epilepticus. NB: the Theta pointu alternant can be found in status of the
neonatal period from other aetiologies eg: Hypocalcaemia, meningitis, I C
hemorrhages) and is not specific to the benign neonatal seizures. However it is
a GOOD prognostic factor since it always carries a favorable NEUROLOGICAL
Recorded seizures can be found al over the scalp but are most frequently in the Rolandic
area. Occasionally can be unilateral, immediately generalised or secondarily
generalized. EEG tracing are spikes or slow waves. There is no post critical
flattening (which would be of poor prognosis) and no alpha-like rhythm. There
can be clinical seizures without EEG anomalies and EEG critical discharges
without clinical seizures.
status many drugs have been tried (PHB, DPH, BZD, Paraldehyde, Chloral, ...) Mot
of the times the seizures stop spontaneously and it seems that the AED's do not
modify the duration of the status.
diagnosis: MB imbalance
Possibly a deficit in Zinc in the CSF. (Goldberg and Sheehy 1983, Arch. Dis.