Iman G Mahmoud1, Marwa Mahmoud2, Miral Refaat2, Marian Girgis1, Nevin Waked3, Ameera El Badawy1, Laila Selim1, Sawsan Hassan4, Alice K Abdel Aleem5. 1. Neurology and Neurometabolic Departments, Cairo University Children Hospital, Cairo, Egypt. 2. Stem Cell Research Laboratory, Centre for Advanced Sciences-National Research Centre, Cairo, Egypt. 3. Department of Pediatrics, 6(th) October University, Cairo, Egypt. 4. Genetics and Neurometabolic Departments, Cairo University Children Hospital, Cairo, Egypt. 5. Stem Cell Research Laboratory, Centre for Advanced Sciences-National Research Centre, Cairo, Egypt; Neurogenetics Laboratory, Weill Cornell Medical College in Qatar, Doha, Qatar; Department of Neurology, Weill Cornell Medical College, New York, New York. Electronic address: aka2005@qatar-med.cornell.edu.
Abstract
BACKGROUND: Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a rare and genetically heterogeneous cerebral white matter disease. Clinically, it is characterized by macrocephaly, developmental delay, and seizures. We explore the clinical spectrum, neuroimaging characteristics, and gene involvement in the first patients with megalencephalic leukoencephalopathy with subcortical cysts described from Egypt. PATIENTS: Six patients were enrolled from three unrelated families. Patient inclusion criteria were macrocephaly, developmental delay, normal urinary organic acids, and brain imaging of diffuse cerebral white matter involvement. Direct sequencing of the MLC1 gene in patients' families and GliaCAM in one questionable case was performed using BigDye Terminator cycle sequencing. RESULTS: Clinical heterogeneity, both intra- and interfamilial, was clearly evident. Developmental delays ranged from globally severe or moderate to mild delay in achieving walking or speech. Head circumference above the ninety-seventh percentile was a constant feature. Neuroimaging featured variability in white matter involvement and subcortical cysts. However, findings of posterior fossa changes and brain stem atrophy were frequently (66.6%) identified in these Egyptian patients. Discrepancy between severe brain involvement and normal mental functions was evident, particularly in patients from the third family. MLC1 mutations were confirmed in all patients. Deletion/insertion mutation in exon 11 (c.908-918delinsGCA, p.Val303 Gly fsX96) was recurrent in two families, whereas a missense mutation in exon 10 (c.880 C > T, p.Pro294Ser) was identified in the third family. CONCLUSIONS: This report extends our knowledge of the clinical and neuroimaging features of megalencephalic leukoencephalopathy with subcortical cysts. It confirms the apparent lack of selective disadvantage of MLC1 mutations on gamete conception and transmission as supported by the presence of multiple affected siblings in Egyptian families.
BACKGROUND:Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a rare and genetically heterogeneous cerebral white matter disease. Clinically, it is characterized by macrocephaly, developmental delay, and seizures. We explore the clinical spectrum, neuroimaging characteristics, and gene involvement in the first patients with megalencephalic leukoencephalopathy with subcortical cysts described from Egypt. PATIENTS: Six patients were enrolled from three unrelated families. Patient inclusion criteria were macrocephaly, developmental delay, normal urinary organic acids, and brain imaging of diffuse cerebral white matter involvement. Direct sequencing of the MLC1 gene in patients' families and GliaCAM in one questionable case was performed using BigDye Terminator cycle sequencing. RESULTS: Clinical heterogeneity, both intra- and interfamilial, was clearly evident. Developmental delays ranged from globally severe or moderate to mild delay in achieving walking or speech. Head circumference above the ninety-seventh percentile was a constant feature. Neuroimaging featured variability in white matter involvement and subcortical cysts. However, findings of posterior fossa changes and brain stem atrophy were frequently (66.6%) identified in these Egyptian patients. Discrepancy between severe brain involvement and normal mental functions was evident, particularly in patients from the third family. MLC1 mutations were confirmed in all patients. Deletion/insertion mutation in exon 11 (c.908-918delinsGCA, p.Val303 Gly fsX96) was recurrent in two families, whereas a missense mutation in exon 10 (c.880 C > T, p.Pro294Ser) was identified in the third family. CONCLUSIONS: This report extends our knowledge of the clinical and neuroimaging features of megalencephalic leukoencephalopathy with subcortical cysts. It confirms the apparent lack of selective disadvantage of MLC1 mutations on gamete conception and transmission as supported by the presence of multiple affected siblings in Egyptian families.
Authors: Ghada M H Abdel-Salam; Mohamed S Abdel-Hamid; Samira I Ismail; Heba Hosny; Tarek Omar; Laila Effat; Mona S Aglan; Samia A Temtamy; Maha S Zaki Journal: Metab Brain Dis Date: 2016-07-07 Impact factor: 3.584
Authors: Sun Ah Choi; Soo Yeon Kim; Jihoo Yoon; Joongmoon Choi; Sung Sup Park; Moon Woo Seong; Hunmin Kim; Hee Hwang; Ji Eun Choi; Jong Hee Chae; Ki Joong Kim; Seunghyo Kim; Yun Jin Lee; Sang Ook Nam; Byung Chan Lim Journal: Ann Lab Med Date: 2017-11 Impact factor: 3.464