Angelman syndrome and pseudo-hypsarrhythmia: a diagnostic pitfall

Angelman syndrome is a rare genetic disorder scarcely diagnosed before the age of two years. We report the case of an eight-month-old female presenting with severe hypotonia, myoclonus, suspected spasms and an electroencephalogram with hypsarrhythmic-like features. She was initially treated with vigabatrin which resulted in worsening of myoclonic jerks. Fluorometric in situ hybridization revealed a chromosomal deletion at region 15q11–13.We discuss the case and differential diagnosis with other conditions including West syndrome. [Published with video sequences]

[1]  B. Dan.  Angelman syndrome: Current understanding and research prospects , 2009, Epilepsia.

[2]  Kazuyoshi Watanabe,et al.  Evolution of seizures and electroencephalographical findings in 23 cases of deletion type Angelman syndrome , 2005, Brain and Development.

[3]  S. G. Boyd,et al.  The EEG in early diagnosis of the Angelman (Happy Puppet) syndrome , 1988, European Journal of Pediatrics.

[4]  K. Valente,et al.  Angelman Syndrome: Difficulties in EEG Pattern Recognition and Possible Misinterpretations , 2003, Epilepsia.

[5]  R. Guerrini,et al.  Angelman Syndrome , 2003, Paediatric drugs.

[6]  D. J. Driscoll,et al.  Angelman syndrome: mimicking conditions and phenotypes. , 2001, American journal of medical genetics.

[7]  J. Clayton-Smith,et al.  Angelman syndrome phenotype associated with mutations inMECP2, a gene encoding a methyl CpG binding protein , 2001, Journal of medical genetics.

[8]  A. Fois,et al.  Diagnosis of Angelman syndrome: clinical and EEG criteria , 1999, Brain and Development.

[9]  J. Ostergaard,et al.  [EEG and early diagnosis of Angelman syndrome]. , 1997, Ugeskrift for laeger.

[10]  H. Stroink,et al.  Evolution of Epilepsy and EEG Findings in Angelman Syndrome , 1997, Epilepsia.

[11]  D. Giardino,et al.  Angelman's Syndrome in the First Year of Life , 1990, Developmental medicine and child neurology.

[12]  J D Frost,et al.  Hypsarrhythmia: Variations on the Theme , 1984, Epilepsia.

[13]  J. Frost,et al.  Sleep characteristics in infantile spasms , 1981, Neurology.

[14]  Harry Angelman,et al.  ‘Puppet’ Children A Report on Three Cases , 1965 .