What is Kerley's sign (Kerley B lines)?

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From the Research

Kernig's sign is a clinical test used to detect meningeal irritation, characterized by resistance or pain when extending the knee with the hip flexed at a 90-degree angle, indicating possible meningitis. This sign is one of the classical clinical signs used to aid in the diagnosis of meningitis, along with nuchal rigidity and Brudzinski's sign, as described in a study published in the Archives of disease in childhood. Education and practice edition 1. The test for Kernig's sign, as currently performed, differs from Kernig's original description, but it remains a useful tool in detecting meningeal irritation, as noted in a study published in Reviews of infectious diseases 2. Some key points to consider when using Kernig's sign in clinical practice include:

  • The sign relies on the principle that stretching the inflamed meningeal membranes causes clinically detectable irritation.
  • Positive meningitic signs, including Kernig's sign, increase the likelihood of a diagnosis of meningitis.
  • The absence of meningitic signs reduces the probability of meningitis, but does not rule it out.
  • Kernig's sign is most useful when combined with other features in the history and examination to contribute to a comprehensive clinical assessment, as highlighted in a study published in 2020 1.

References

Research

How to use clinical signs of meningitis.

Archives of disease in childhood. Education and practice edition, 2020

Research

Kernig's and Brudzinski's signs revisited.

Reviews of infectious diseases, 1987

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This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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