Neonatal stress hyperglycemia mimicking diabetes mellitus secondary to massive intraparenchymal brain abscess due to escherichia coli sepsis: A case report.

Stress hyperglycemia is a common metabolic response in critically ill neonates but may rarely present with extreme hyperglycemia mimicking neonatal diabetes mellitus. We report a term female neonate presenting on day 18 of life with lethargy, poor feeding, dehydration, and severe hyperglycemia (>1000 mg/dL), hypernatremia, and acute kidney injury. Insulin therapy was initiated due to suspicion of neonatal diabetes mellitus. Blood cultures grew Escherichia coli, confirming neonatal sepsis. Neuroimaging revealed a massive right fronto-parieto-temporal intraparenchymal abscess with significant mass effect and midline shift. The patient underwent staged neurosurgical intervention including anterior fontanelle aspiration followed by right frontal craniotomy and abscess evacuation. Pus culture confirmed multidrug-resistant Escherichia coli, and targeted antimicrobial therapy was administered. Follow-up imaging demonstrated reduction in abscess size with residual ventriculitis and gliotic changes. Genetic testing for neonatal diabetes mellitus was negative. Hyperglycemia resolved completely following infection control and discontinuation of insulin therapy, confirming stress hyperglycemia. This case highlights the diagnostic challenge in differentiating stress hyperglycemia from neonatal diabetes mellitus and emphasizes the importance of early neuroimaging and prompt neurosurgical intervention in neonates with sepsis and neurological manifestations. Early recognition and multidisciplinary management are critical to improving survival and neurological outcomes.