Collect the specimen under sterile conditions. Three or four tubes (1 mL per tube) of CSF should be collected. The third tube is used for cell count and differential; the others can be used for microbiologic and chemical studies.
Seal immediately to prevent leakage or contamination. Label the specimen with the patient’s name, date, and tests ordered and send the specimen to the laboratory without delay.
Alert laboratory staff so that the specimen can be examined immediately.
Notify the healthcare provider as soon as results are obtained so that appropriate treatment can be started in a timely fashion.
If the CSF specimen cannot be delivered to the laboratory immediately, the container should be stored at room temperature.
No more than 4 hours should elapse before laboratory analysis takes place because of the low survival rates of the organisms causing meningitis (especially H. influenzae and N. meningitidis).
Clinical Alert
In cases of suspected meningitis, a culture should be done and a diagnosis made as quickly as possible. This is important because some causative organisms cannot tolerate temperature changes. If a viral cause is suspected, a portion of the CSF should be refrigerated (0 °C–4 °C). Freezing is not recommended unless inoculation into tissue culture will take longer than 5 days. If polymerase chain reaction (PCR) testing is to be performed, specimens may need to be frozen immediately.
Clinical Alert
Newborns have the highest prevalence of meningitis of any age group. Organisms causing infection in the newborn (usually acquired during the birth process) include group B streptococcus, E. coli, and L. monocytogenes.
Clinical Alert
CSF findings may not differentiate between bacterial and viral meningitis. Generally, however, white blood cell counts of 1000–10,000 cells/L are associated with a bacterial cause, whereas counts from 100 to 1000 cells/L are associated with an underlying viral origin.