Secondary Intracranial Hypertension in Pediatric Patients With Cryopyrin-Associated Periodic Syndrome

Background: Cryopyrin-associated periodic syndrome is characterized by periodic fever, rash, and joint pain. Papilledema rarely occurs. We present our series of patients with cryopyrin-associated periodic syndrome who clinically met the diagnostic criteria for Muckle-Wells syndrome and our experience with secondary intracranial hypertension.

Methods: Retrospective review of all patients with cryopyrin-associated periodic syndrome at Nationwide Children's Hospital from October 2015 to September 2017.

Results: Eighteen children met inclusion criteria: 15 females and three males, aged 1.5 to 16.2 years. Fifteen had periodic fever genetic testing; three had a known genetic defect identified, eight had a defect identified not currently known to be associated with cryopyrin-associated periodic syndrome, and four had no defect identified. Six patients (30%) developed headaches and were diagnosed with secondary intracranial hypertension. Lumbar puncture opening pressures ranged from 28 to 45 cm H₂O. Only one patient had papilledema. Initial treatment was medical in all cases, by increasing interleukin-1 inhibitor dose and/or acetazolamide. One patient required a ventriculoperitoneal shunt for headache management. No visual acuity loss was detected. All six patients with secondary intracranial hypertension had a known genetic mutation or genetic variant of unknown significance; five involved the NLRP3 gene.

Conclusions: In our series of 18 patients with cryopyrin-associated periodic syndrome, secondary intracranial hypertension occurred at a higher than expected rate. We suspect that genetic defects involving the NLRP3 gene may be a risk factor. Papilledema was present in only one patient. Physicians treating cryopyrin-associated periodic syndrome should be aware of this vision-threatening association and potential therapeutic approach.

Keywords: Cryopyrinopathy; Intracranial hypertension; Muckle-Wells syndrome; Papilledema.