Hi Dick, Did you check their EEG? There are patients with "periodic spasms", a specific form of secondary generalization. It is characterized by clusters of spasms and looks like infantile spasms, but without hypsarrhythmia.

It's quite possible for infantile spasms (aka epilepsy, aka seizures)to continue beyond infanthood.  However, seizures that first occur after infancy are more likely to be called epileptic seizures or epilepsy--for terminological reasons.  There are high-quality websites that can tell you more than I ever can about this; if the links don't work, just copy and paste one of these Web addresses into your browser.

http://infantilespasmsproject.org/

http://www.webmd.com/children/west-syndrome

http://infantilespasmsproject.org/

http://www.webmd.com/children/west-syndrome

Of course the can do, but the terminology is rather different then. A good review about late onset epileptic spasms is linked.

http://www.ncbi.nlm.nih.gov/pubmed/24907139

Thanks Abdulhafeez, Douglas. and Tomonari, these answers are very helpful. I am not a neurologist but my understanding that is that the EEGs in MECP2 Duplication Syndrome are similar to hysarrhythmia (chaotic with almost continuous spiking) but differ, too, in some ways.

Most pure infantile spasms occur within the first 2 years of life, other than the exceptions mentioned before.

Infantile spasms (IS) are type of epileptic seizures started in first year of life (infancy).They have tonic component (either flexion or extension) and usually is associted with Epileptic Encephalopathy (EE) during infancy (Ohtahara sy and West sy ). Later on they can be presented also as a part of Lennox Gastaut syndrome,  (one of EE during childhood), where is better use term tonic spasm. The same type of epileptic seizure can be seen in adults . You can see good paper from 2007 with video polygraphic study (Giuseppe d’Orsi, Vincenzo Demaio, Mauro G Minervini. Adult epileptic spasms: a clinical and video-polygraphic study

Epileptic Disorder Volume 9, issue 3, September 2007).

Regards

Bosa

Pediatric Neurologist/Pediatric Epilepologist

http://www.jle.com/en/revues/epd/e-docs/adult_epileptic_spasms_a_clinical_and_video_polygraphic_study_275678/article.phtml?tab=texte

In my personal experience, I have often sometimes seen epileptic spasms occurring beyond the 1st or 2nd year of life, either in my patients or in patients whose EEG I have read. As mentioned above, EEG shows diferent patterns, not hypsarrytmia. Patients I have seen with later-onset or persistente spasms included: a case of tuberous sclerosis with persisting spasms (now 9 years old), a patient with Norrie disease (spasms started in adolescence), and a girl with "cryptogenic late-onset spasms" who started sezires by the age of 4. Other patients who have this type of seizures include chromomosomal abnormalities and some epileptic encephalopathies, in some cases with spasms, tonic seizures and "tonic spasms".