Early-Onset Epileptic Encephalopathy and Neurodevelopmental Regression Associated With ST3GAL5 Deficiency.
Sabire Gokalp, Elif Guler, Mustafa Kilic
✦ AI-curated · Sources linked
Case in brief
A Turkish male infant presented with developmental delay and hypotonia, progressing to refractory epilepsy and neurodevelopmental regression. Neuroimaging revealed diffuse cerebral atrophy and ventriculomegaly, while audiological assessment showed bilateral sensorineural hearing loss. Whole-exome sequencing identified a likely pathogenic variant in ST3GAL5, confirming GM3 synthase deficiency. The patient required gastrostomy and tracheostomy due to feeding dysfunction, and long-term follow-up revealed renal and hepatobiliary abnormalities.
What made this case unusual
The presence of renal calculi and hepatobiliary abnormalities, including biliary sludge and gallstones, during follow-up is atypical for GM3 synthase deficiency.
Diagnostic / clinical pearl
Comprehensive genetic testing is essential for infants with unexplained epileptic encephalopathy and developmental regression, as routine metabolic screenings may yield non-specific results.
Why it matters
This case underscores the importance of multisystem surveillance in patients with severe neurological conditions, as atypical features may emerge over time.