Microbiology

Cerebrospinal Fluid (CSF)

CSF taken by lumbar puncture (CSF LP)

  • Four samples of CSF should be collected into clearly labelled sterile containers, which indicate the sequence order of sampling. Sample 2 (0.5 mL minimum) should be in a fluoride/oxalate tube for glucose. Samples 1, 3 and 4 (each 1.5 mL minimum) should be in plain sterile tubes.
  • Samples 1 and 3 should be delivered to Microbiology without delay.
  • Samples 2 and 4 should be delivered to Biochemistry without delay.
  • Do not use the pneumatic tube delivery system.
  • At least 2 ml of specimen is required for full bacteriological examination.
  • State whether the patient has received any antimicrobial chemotherapy before collection of the specimen.
  • Where bacterial meningitis is suspected a blood culture, a blood sample in EDTA bottle for PCR and a posterior-pharyngeal swab should also be taken.
  • Where Mycobacterium tuberculosis meningitis is suspected (CSF TB) ¬†film for acid fast bacilli and tubercle culture may also be done on request.
  • Where a fungal infection is suspected this must be clearly stated on the request.

For viral meningitis – see Virology section.

CSF sample is taken from a ventricular tap (CSF Vent), drain (CSF Drain) or other site (CSF other)

  • Please clearly state the site.
  • Number of aliquots taken will depend on recommendations in departmental protocols. Please clearly label urgent specimens with the name and contact number for receipt of microscopy results.