Table 2

- Metabolic and genetic causes among 150 children with epilepsy below 2 years of age.

Metabolic causes (total No. 10 (6.7%))

  • Aminoacylase deficiency (ACY1)

  • Congenital Methemoglobinemia (CYB5R3), G6PD Deficiency

  • Malonic acidemia (MAL)

  • Hemizygous pathogenic variant in G6PD gene

  • Succinic semialdehyde dehydrogenase (SSADH) deficiency (ALDH5A1)

  • Pyridoxal 5 phosphate dependent epilepsy (PNPO)

  • Biotinidase deficiency

  • Rhizomelic chondrodysplasia punctate type 2 (GNPAT)

  • Sanfilippo A (MPS3A)

  • Sulfite Oxidase deficiency (SUOX)

Genetic causes (total No. 43 (28.7%))

  • SCN1A-related seizure disorder

  • Dravet syndrome (SCN1A)

  • Benign familial Neonatal convulsion (KCNQ2)

  • Early Infantile Epileptic Encephalopathy (SCN2A)

  • Early Infantile Epileptic Encephalopathy type 7 (KCNQ2)

  • Early Infantile Epileptic Encephalopathy type 9 (PCDH19)

  • Early Infantile Epileptic Encephalopathy type 11 (SCN2A)

  • Early infantile Epileptic Encephalopathy Type 14 (KCNT1)

  • Early Infantile Epileptic Encephalopathy type 18 (SZT2)

  • Early infantile Epileptic Encephalopathy type 25 (SLC13A5)

  • Early Infantile Epileptic Encephalopathy type 35 (ITPA)

  • Earli Infantile Epileptic Encephalopathy type 49 (DENND5A)

  • Early Infantile Epileptic Encephalopathy type 66 (PACS2)

  • GLUT1 deficiency (SLC2A1)

  • Infantile spasm (CACNB4)

  • Epileptic encephalopathy, brain malformation (EML1)

  • Autosomal Recessive Neurodevelopmental disorder with microcephaly, cataract and renal abnormalities (GEMIN4)

  • GEMIN4- related phenotype with global developmental delay and congenital cataract

  • Pseudo-TORCH syndrome (USP18)

  • Epilepsy, progressive myoclonic (NHLRC1)

  • Autosomal dominant Wiedemann-Steiner syndrome (KMT2A)

  • X-linked epilepsy with variable learning disabilities and behavior disorders (SYN1)

  • Autosomal recessive microcephaly, seizers, and developmental delay (MCSZ) (PNKP)

  • Autosomal recessive spinocerebellar ataxia type 20 (SNX14)

  • Ischemic stroke secondary to heterozygous G20210A factor II prothrombin mutation in F2 gene

  • Tuberous Sclerosis Complex (TSC2)

  • Sturge-Weber syndrome.

  • Rett syndrome (FOXG1)

  • Down Syndrome and Epileptic Encephalopathy (Infantile spasm)

  • Galloway-Mowat syndrome (WDR73)

  • Joubert syndrome (CC2D2A)

  • Aicardi Goutieres syndrome (type AGS- 3