|
|
||||||||
From the Department of General Pediatrics, University Childrens Hospital, Duesseldorf, Germany.
Address correspondence and reprint requests to Dr. Daniel Tibussek, Department of General Pediatrics, Division of Paediatric Neurology, University Childrens Hospital, Heinrich-Heine-University Düsseldorf, Moorenstr. 5, D-40225 Düsseldorf, Germany daniel.tibussek{at}med.uni-duesseldorf.de
| SECTION 1 |
|---|
|
|
|---|
We were able to observe more than 20 of these episodes within a period of 48 hours while he was hospitalized (example given in video 3).
Questions for consideration:
| SECTION 2 |
|---|
|
|
|---|
On the basis of published descriptions of similar fits in infancy,1 the diagnosis of shuddering attacks was suspected. No further diagnostic workup was undertaken.
On follow-up the frequency of the attacks gradually decreased, and they eventually seemed to have ceased after 3 months. However, at the age of 15 months the episodes resumed, and another home video was sent to us. At this time the attacks were provoked by an attempt to stick a fork into a piece of bread (video 4). In addition, the mother had observed shuddering attacks provoked by pressing Lego bricks together. This relapse lasted for less than 1 week and was followed by another uneventful period of 6 months. Again, after that time the parents observed sporadic shuddering attacks (not more than one a day) which were somewhat milder than at original presentation.
At the age of 24 months the parents provided another video documenting a third relapse (video 5). While playing with his mother the child is pretending to wash his hair and in the end is asked to shake his head in order to "dry his hair." However, in attempting to shake his head he provokes another shuddering attack. Again and again the mother could reproduce this phenomenon. At the last follow-up, aged 26 months, the parents reported shuddering attacks frequently occurring just after coming out of the bath.
Questions for consideration:
| SECTION 3 |
|---|
|
|
|---|
No family history of essential tremor was reported.
| DISCUSSION |
|---|
|
|
|---|
Shuddering attacks are not epileptic in nature. Ictal EEG is normal in this syndrome, and typically no neurologic abnormalities are found. However, confusion with tonic, myoclonic, and absence seizures, and with West syndrome, has been reported. This misdiagnosis may lead to unnecessary anticonvulsive treatment.5 Therefore, EEG is advocated in all patients and ictal video documentation should always be attempted by caregivers. In cases with unusual clinical presentations, prolonged video EEG monitoring is helpful. Other events which can mimic myoclonic seizures in the infant may also be taken into consideration, mainly benign myoclonus of early infancy or gratification disorder.
The pathophysiology of shuddering attacks is unknown, although a relationship to essential tremor has been postulated.6,7 This was initially based on the observation of six infants and young children presenting with a history of shuddering attacks who exhibited postural tremor on examination and who had a positive family history of tremor.6 Successful treatment of shuddering attacks with propanolol, a first line agent in the treatment of essential tremor, was reported years later.7 Moreover, the EMG pattern during the attacks has been reported to be very similar to that of essential tremor.8 However, a recent study on essential tremor in 39 patients <18 years did not find any patient with a history of shuddering attacks during infancy or among family members.9 Accordingly, in more recent cases reports8,10 no positive family history for essential tremor was reported.
Although the incidence of shuddering attacks has been reported to be low, our personal experience leads us to conclude that the incidence may be underestimated. Since this case presented to our hospital, we were able to diagnose three additional cases within 12 months. In support of this view, a retrospective study of paroxysmal nonepileptic events in 666 pediatric patients found 7% of all events to be shuddering attacks.11
Further investigations in affected infants are usually not indicated. Reassurance of parents is crucial since relatives are often frightened by the unexpected appearance and often high frequency of the attacks. Spontaneous remission can be expected according to previous reports.3
However, if progression occurs or additional neurologic abnormalities are found on examination, further diagnostic evaluation including cerebral imaging is indicated, as there have been reports of symptomatic shuddering attacks.8
| ACKNOWLEDGMENT |
|---|
|
|
|---|
GO TO SECTION 2
GO TO SECTION 3
Disclosure: The authors report no conflicts of interest.
Presented as an abstract at the 32nd annual meeting of the Society for Neuropediatrics.
| REFERENCES |
|---|
|
|
|---|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |