How to use clinical signs of meningitis.

Meningitis is a critical diagnosis not to miss in children presenting with fever. Since the early 20th century, classical clinical signs have been used to aid the diagnosis of meningitis. These classical signs are nuchal rigidity, Kernig's sign and Brudzinski's sign. Each of these relies on the principle that stretching the inflamed meningeal membranes causes clinically detectable irritation. Several primary studies have quantified the diagnostic performance of clinical examination in detecting meningitis in children. The results of these studies vary significantly due to methodological differences, clinical heterogeneity and interobserver variability. However, their findings demonstrate that positive meningitic signs increase the likelihood of a diagnosis of meningitis, and the absence of meningitic signs reduces this probability. These signs have greatest utility when combined with other features in the history and examination to contribute to a comprehensive clinical assessment.