Which diagnostic tests should be prioritized in a patient suspected of having meningitis in a primary care setting?

Guideline-aligned answer with reasoning, red flags and references. Clinically reviewed by Dr Kola Tytler MBBS CertHE MBA MRCGP.

Posted: 14 August 2025Updated: 14 August 2025 Guideline-Aligned (High Confidence) Clinically Reviewed
Dr Kola Tytler MBBS CertHE MBA MRCGPClinical Lead • iatroX

Prioritized diagnostic tests in primary care for suspected meningitis include:

  • Immediate clinical assessment and urgent referral to hospital for further investigations and management, as definitive diagnostic tests are typically performed in secondary care ,.
  • Blood tests before starting antibiotics if possible, including blood culture, white blood cell count (with neutrophils), C-reactive protein (CRP) or procalcitonin (PCT), blood glucose, and whole-blood PCR for meningococcal and pneumococcal pathogens .
  • Bacterial throat swab for meningococcal culture, preferably before antibiotics, if meningococcal disease is suspected .
  • Measurement of blood glucose immediately before lumbar puncture to calculate cerebrospinal fluid (CSF) to blood glucose ratio, although lumbar puncture is generally performed in hospital ,.
  • Lumbar puncture and CSF analysis (including red and white cell counts with differential, total protein, glucose concentration, Gram stain microscopy, microbiological culture and sensitivities, and PCR for relevant pathogens) are essential but usually done in hospital after referral ,.

In summary, in primary care the priority is to perform initial blood tests and bacterial throat swab if feasible, but the key diagnostic procedures such as lumbar puncture and CSF analysis are performed in secondary care following urgent hospital referral ,,.

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