An RCVS Spectrum Disorder? New Daily Persistent Headache Starting as a Single Thunderclap Headache (3 New Cases)

Objective: To describe 3 new cases of new daily persistent headache (NDPH) starting as a single thunderclap headache. Background: NDPH is a form of chronic daily headache that is unique in its temporal profile of onset. Distinct subtypes of NDPH are being described with specific efficacious treatments. A single case of NDPH starting as a single thunderclap headache has been previously reported but no further cases have been documented in the literature. New cases need to be published to better define the syndrome. Methods: To report a case series of patients diagnosed with this unique NDPH subtype at an academic headache center from 2016 to 2018. Results: Three new cases of NDPH starting as a single thunderclap headache at onset were diagnosed. All patients were female with an average age of onset of 46 years. All presented with neurologic symptoms/stroke-like spells at headache onset. No defined triggering events were noted in any of the patients. There is a possible seasonal predilection to develop the syndrome around the fall clock change to the winter solstice. Neuroimaging was normal in the case patients. All patients rapidly responded to nimodipine. The duration of headache prior to nimodipine therapy ranged from 3 months to 4 years. Conclusion: This NDPH subtype appears to be rare. The key to diagnosis is asking about the temporal profile of the onset of the first ever NDPH headache. None of the case patients had been asked about the initial headache and its pattern of onset. Nimodipine seems to be very effective in treating this NDPH subtype. This syndrome is most likely precipitated by persistent or intermittent cerebral artery vasospasm. It is possibly a subform of the reversible cerebral vasoconstriction syndrome.