Neuroimaging features of incontinentia pigmenti: prompting genetic confirmation.

A term female neonate presented with vesicular skin lesions along Blaschko's lines and refractory seizures in the first week of life. Brain MRI revealed multifocal T2/fluid-attenuated inversion recovery hyperintensities and restricted diffusion in the periventricular and subcortical white matter, basal ganglia, thalami, corpus callosum and cerebellum, with microhaemorrhages on susceptibility-weighted imaging. These imaging findings, along with clinical history, suggested incontinentia pigmenti (IP), prompting genetic testing, which confirmed a heterozygous IKBKG exon 4-10 deletion. Seizures were managed with phenobarbitone, levetiracetam, phenytoin and midazolam infusion. Despite initial stabilisation, the patient developed sepsis and acute kidney injury, leading to demise. This case underscores the critical role of MRI in identifying IP's arteriopathy-driven central nervous system lesions, guiding genetic diagnosis and distinguishing IP from herpes simplex virus encephalitis, human parechovirus encephalitis and congenital varicella syndrome. Early neuroimaging is essential for timely diagnosis and management.