Primary Diffuse Leptomeningeal Melanomatosis Leading to Raised Intracranial Pressure in a Pediatric Patient.

A critical clinical consideration, in addition to other common risk factors predisposing individuals to idiopathic intracranial hypertension (IIH), involves the potential co-occurrence of increased intracranial pressure and elevated cerebrospinal fluid protein levels in the presence of underlying malignancies. Primary diffuse leptomeningeal melanomatosis, an exceptionally rare condition with few reported cases in the pediatric population, illustrates this scenario. Timely decision-making based on clinical suspicion to perform a biopsy and involving a skilled pathologist for accurate reporting are essential steps toward achieving a definitive diagnosis.

Distinct neurological phenotypes associated with biallelic loss of NOTCH3 function: evidence for recessive inheritance.

Background: NOTCH3 variants are known to be linked to cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). However, some null NOTCH3 variants with homozygous inheritance cause neurological symptoms distinct from CADASIL. The aim of this study was to expand the clinical spectrum of this distinct condition and provide further evidence of its autosomal recessive inheritance.