Abstract
The term PEHO syndrome is an abbreviation from the first letters of the most important symptoms: progressiveencephalopathy, edema - in particular of the face and extremities, hypsarrhythmia and atrophy of the optic nerve.The authors demonstrate case-records of two female patients who meet the criteria of PEHO syndrome, wherebyin one patient adenylsuccinate lyase deficiency was confirmed. In the second case the authors draw attention tothe long-term therapeutic effect of felbamate in refractory epilepsy which is associated with the disease in themajority of cases.