Spontaneous extracranial hemorrhagic phenomena in primary headache disorders: A systematic review of published cases.

Background Head pain is a cardinal feature of primary headache disorders (PHDs) and is often accompanied by autonomic and vasomotor symptoms and/or signs. Spontaneous extracranial hemorrhagic phenomena (SEHP), including epistaxis, ecchymosis, and hematohidrosis (a disorder of bleeding through sweat glands), are poorly characterized features of PHDs. Aim To critically appraise the association between SEHP and PHDs by systematically reviewing and pooling all reports of SEHP associated with headaches. Methods Advanced searches using the PubMed/MEDLINE, Web of Science, Cochrane Library, Google Scholar, and ResearchGate databases were carried out for clinical studies by combining the terms "headache AND ecchymosis", "headache AND epistaxis", and "headache AND hematohidrosis" spanning all medical literature prior to October 10, 2015. Preferred Reporting Items for Systematic Reviews and Meta-analyses and Meta-analysis of Observational Studies in Epidemiology guidelines were applied. Results A total of 105 cases of SEHP associated with PHDs (83% migraine and 17% trigeminal autonomic cephalgias) were identified (median age 27 years, male to female ratio 1:2.3); 63% had epistaxis, 33% ecchymosis, and 4% hematohidrosis. Eighty-three percent of studies applied the International Classification of Headache Disorders diagnostic criteria. Eighty percent of the reported headaches were episodic and 20% were chronic. Twenty-four percent of studies reported recurrent episodes of SEHP. Conclusions Our results suggest that SEHP may be rare features of PHDs. Future studies would benefit from the systematic characterization of these phenomena.