The Tricky Diagnosis of Nummular Headaches: Description of Two Cases and Literature Review

Nummular headaches are a rare and relatively newly characterized primary headache disorder. The epidemiology is largely unknown due to likely underdiagnosis and a small population of all headache patients in outpatient presentation. Though our understanding of nummular headaches continues to evolve, they remain a diagnostic challenge for physicians and the underlying pathophysiology is poorly understood. Hypotheses consider neuralgia stemming from epicranial tissues as well as undergoing observation of varying prevalence of autoimmune markers. Peripheral nociception versus central sensitization needs to be evaluated as well, with cases not having consistent direction. Selecting treatment options can be challenging due to limited efficacy, the vague nature of reported symptoms, the rarity of the diagnosis, and the range of presentations. Several treatment modalities have been utilized including non-steroidal anti-inflammatory drugs (NSAIDs), beta-blockers, botulinum toxin injection, transcutaneous nerve stimulation, or even simple reassurance. A case-by-case analysis must be undertaken to best develop treatment options for affected individuals as high-quality randomized quality trials for nummular headaches are very few. We detail two novel cases of patients presenting with nummular headaches that highlight the challenges and importance of making the diagnosis and weighing treatment options for improved levels of patient care, which is followed by a literature review.