Concomitant occurrence of different trigeminal autonomic cephalalgias: a case series and review of the literature.

Introduction: The trigeminal autonomic cephalalgias (TACs) subsume four primary headache disorders. Hemicrania continua is increasingly regarded as an additional TAC. In rare cases patients may present with two different TACs or a TAC and hemicrania continua.
Cases: We report four patients with two different TACs or one TAC and hemicrania continua. Two patients presented with cluster headache and paroxysmal hemicrania, one patient with cluster headache and hemicrania continua, and one patient suffered from cluster headache and SUNCT.
Discussion: While the International Classification of Headache Disorders (ICHD-II) proposes specific diagnostic criteria, the variability of clinical presentation may make clear diagnosis difficult. All patients fulfilled the ICHD-II criteria. The manifestation of two different TACs or hemicrania continua in one patient is uncommon but possible and should be taken into account especially when chronic headache patients present with changing headache symptoms.