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Two cases of variant late infantile ceroid lipofuscinosis in Jordan
Omar Nafi1, Bashar Ramadan2, Olaf Riess3
1Department of Pediatrics, Faculty of Medicine, Mutah University, Al Karak 61710, Jordan. omarnafi@mutah.edu.jo.
Background:
Late infantile ceroid lipofuscinosis is a rare neurodegenerative disorder that appears between the ages of 2 and 4 years and is difficult to diagnose. In this report we present two sisters with this condition, and the clinical course consisted of delayed developmental skills initially and later regression of previously acquired skills. The cases were initially considered as childhood disintegrative disorder (CDD); however, when whole exome sequencing (WES) genetic testing was done, they proved to be variant late infantile ceroid lipofuscinosis. This is the first report from Jordan.
Case Summary:
Clinical presentation included developmental delay and initially speech delay, followed by lose of sphincter control. Motor development was normal until 4 years of age, then they developed ataxia (fear of going downstairs) and weakness while walking. Atonic and myoclonic seizures become intractable, and this was followed by inability to stand or sit and loss of expressive language. In addition to complete blood count test, liver function test, kidney function test, serum electrolyte test, and blood sugar test, serum amino acid profile, B12 level test, thyroid function test, and a brain computed tomography scan were also normal. An electroencephalogram showed a generalized spike and wave pattern, and magnetic resonance imaging showed little to no abnormalities. After dealing with the cases as CDD, WES testing proved a final diagnosis of variant late infantile ceroid lipofuscinosis. Current treatment is anti-epileptic drugs and supportive care at home, and they are now in vegetative state.
Conclusion:
This report highlights the importance of WES for the identification of genetic diseases, especially neurodegenerative disorders.
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