Congenital generalized lipodystrophy type 1 presenting with prominent immaturebrown adipose tissue in a preterm neonate: a case report

Congenital generalized lipodystrophies (CGL) are genetic disorders characterized by generalized lipoatrophy and severe metabolic complications. Neonatal diagnosis remains uncommon because the typical phenotype may not yet be fully established. We report a preterm female neonate presenting with rapidly progressive bilateral cervical, axillary, and inguinal masses. Imaging and histopathological examination identified prominent immature brown adipose tissue. Severe hypertriglyceridemia prompted suspicion of CGL, which was subsequently confirmed by identification of a homozygous pathogenic AGPAT2 variant. During follow-up, generalized lipoatrophy, insulin resistance, and hepatic steatosis progressively developed, whereas the brown adipose tissue deposits completely regressed by 8 months of age. Nutritional management with a medium-chain triglyceride-enriched formula resulted in marked metabolic improvement. This case highlights that prominent immature brown adipose tissue associated with severe neonatal hypertriglyceridemia may represent an early manifestation of CGL1 and should prompt early genetic investigation.