Existing CRP Test Proves Effective for Faster Diagnosis of Bacterial Meningitis

Researchers at Amsterdam UMC have shown that a widely used diagnostic tool—the C-reactive protein (CRP) test—can also be applied to cerebrospinal fluid (CSF) to quickly and accurately detect life-threatening bacterial meningitis. While CRP testing is already common in blood to identify inflammation and bacterial infections, its use in spinal fluid marks a significant and practical advancement.

Bacterial meningitis is a critical condition, with one in six patients dying and half of survivors experiencing long-term complications. Fast and accurate diagnosis is essential. Neurologist Matthijs Brouwer explains: “Distinguishing bacterial meningitis from other similar conditions can be difficult. Until now, we lacked reliable tools to make that distinction quickly.”

A new application of a proven marker

The Amsterdam UMC team found that elevated CRP levels in CSF are a strong and specific indicator of bacterial meningitis. Although CRP testing in blood is routine, its diagnostic value in CSF had not been thoroughly investigated. Following successful lab trials, the researchers confirmed that the same devices used to measure CRP in blood are sensitive enough to detect it in spinal fluid as well. Prof. Brouwer says, ‘It is a major advantage that existing lab infrastructure can be used for this purpose. Test results are available within 30 minutes of a spinal tap, allowing timely treatment to begin.’

“Any laboratory that currently measures CRP in blood can start using this test for spinal fluid tomorrow.”

Matthijs Brouwer

Professor of Neurology at Amsterdam UMC

From research to clinical practice

Since June 2024, the method has been implemented in routine clinical practice at Amsterdam UMC. The study conducted by Prof. Brouwer and colleagues describes its introduction and real-world effectiveness. According to Prof. Brouwer, ‘All patients with bacterial meningitis had elevated CRP levels in their CSF. Only one patient without meningitis showed a false positive.’ The test also performed reliably in additional studies involving children and patients in Denmark.

Because it uses existing equipment and costs €3 to €5 per test, this approach offers a simple, affordable, and scalable solution to improve meningitis diagnosis and treatment timelines. Prof. Brouwer adds, ‘We never imagined this would be in use with patients less than a year after we began investigating it.’

Read the scientific publication here.