Headache in infections

This review explores the phenomenology, pathogenesis, and nosology of headaches associated with infections, an often-overlooked yet clinically significant symptom. With the increasing recognition of secondary headaches in infections, understanding their clinical patterns, mechanisms, and classifications is crucial for accurate diagnosis and management. Headaches in infections are ubiquitous but vary in presentation, severity, and underlying mechanisms depending on the causative pathogen. Elevated intracranial pressure, meningeal irritation, and activation of the trigeminovascular system are key contributors to headache generation, which varies depending on each pathogen. Pathogen-specific predilection for one of these mechanisms may subtly alter the clinical phenotype of the headache, which can be used to guide management. Emerging evidence highlights postinfectious headache syndromes, particularly following bacterial meningitis and SARS-CoV-2 infection, underscoring the need for long-term follow-up in these patients. The diverse presentations of infection-related headaches necessitate a systematic approach to evaluation and management. While the pathophysiology is complex and multifaceted, understanding these mechanisms aids in differentiating primary headaches from those secondary to infections.