Senior-Løken syndrome and intracranial hypertension

Background: Senior-Løken syndrome (SLS) is a rare autosomal recessive disease characterised by nephronophthisis and retinal degeneration, and belongs to a group of genetically heterogeneous disorders known as the ciliopathies.

Materials and methods: Case report of a patient with genetically proven SLS presenting with headaches and swollen optic nerve heads, review of medical notes and ophthalmic imaging, with retinal photography, fundus autofluorescence, and OCT retinal nerve fibre layer analysis.

Results: We present findings in a 15 year old girl with Senior-Løken syndrome associated with compound heterozygous mutations in the SDCCAG8 gene, who initially presented with a retinal dystrophy, and subsequent renal failure requiring renal transplantation and immunosuppression. Four and a half years later, she presented with headaches, reduced vision and clinical findings of papilloedema. Cerebrospinal fluid analysis revealed a high opening pressure of 37cmH₂0 and neuroimaging was otherwise unremarkable. Treatment with a reduced dose of oral acetazolamide resulted in symptomatic relief of headaches, and resolution of optic nerve swelling.

Conclusion: The association of intracranial hypertension in a ciliopathy is a rare occurrence. The aetiology of intracranial hypertension in this case is likely multi-factorial, due to renal transplantation, post-renal transplant medications and/ or weight gain. With evidence of cilia involvement in the central nervous system, ciliary dysfunction may contribute to intracranial hypertension, and should be considered in these patients presenting with headaches. Diagnosis may be difficult with advanced retinal degeneration and baseline retinal nerve fibre layer thinning. Treatment requires careful monitoring of renal function.

Keywords: Senior-Løken syndrome; ciliopathy; intracranial hypertension; nephronophthisis; retinal dystrophy.