From the Guidelines
Lumbar puncture lab testing should include opening pressure, CSF and serum glucose, CSF protein, 2x MC&S, virology PCR, and lactate, as recommended by the most recent guidelines 1. When performing a lumbar puncture, it is essential to consider the potential complications, such as increased intracranial pressure, coagulopathy, and skin infection at the injection site, as highlighted in a study published in 2017 1. However, the value of a lumbar puncture for diagnostic purposes usually exceeds the risk of complications from the procedure. The following tests should be included in the lumbar puncture lab testing:
- Opening pressure measurement
- CSF and serum glucose
- CSF protein
- 2x MC&S (microbiology and culture)
- Virology PCR
- Lactate Additional tests, such as paired oligoclonal bands, may be considered every 24 hours, as suggested by the guidelines 1. It is also important to note that the UK Joint Specialist Societies guideline on the diagnosis and management of acute meningitis and meningococcal sepsis in immunocompetent adults recommends documenting or requesting the following during a lumbar puncture: CSF opening pressure, CSF glucose with concurrent plasma glucose, and CSF protein 1. In terms of prioritizing the single most recent and highest quality study, the 2017 study published in the Journal of Infection provides valuable insights into the complications of lumbar puncture and the importance of careful assessment of potential contraindications 1. However, the 2012 guidelines from the Association of British Neurologists and British Infection Association provide more specific recommendations for lumbar puncture lab testing 1.
From the Research
Lumbar Puncture Lab Testing
- Lumbar puncture (LP) is a diagnostic procedure used to collect cerebrospinal fluid (CSF) for laboratory analysis, commonly performed to rule out meningitis 2.
- The procedure involves inserting a needle into the spinal canal to collect CSF, which is then analyzed for various parameters such as glucose, protein, and white blood cell count 3.
- The accuracy of biochemical analysis of CSF in diagnosing bacterial meningitis has been studied, with parameters such as CSF-blood glucose ratio, CSF white blood cell count, and CSF lactate level showing high likelihood ratios for diagnosing bacterial meningitis 2.
Indications and Contraindications
- Lumbar puncture is commonly performed to evaluate acute headache and investigate inflammatory or infectious diseases of the nervous system 3.
- Contraindications to lumbar puncture include increased intracranial pressure, space-occupying lesions, and bleeding disorders 4.
Procedure and Complications
- The procedure of lumbar puncture involves anatomy, needle selection, needle insertion, measurement of opening pressure, and CSF specimen handling 3.
- Complications of lumbar puncture include headache, nerve damage, and infection, although serious complications are rare 2, 4.
Repeat Lumbar Puncture
- Repeat lumbar puncture may be performed in selected cases to confirm diagnosis, exclude relapsing or persistent infection, or for therapeutic purposes 5.
- Delayed lumbar punctures can affect the diagnosis of acute bacterial meningitis, with CSF culture positivity decreasing with time after starting antibiotics 6.