Pressures less than 20 cm H2O are considered normal as pressures more than 20 indicate increased spinal pressure, possibly due to bleeding, infection, or the presence of tumors.
Normal CSF should be clear and colorless. Pink-red or orange color indicates the red blood cells are present, while yellow CSF indicates bilirubin present due to hemolysis of RBCs. Possible causes include jaundice, increased CSF protein, subarachnoid hemorrhage, hemoglobinemia, or hypercarotenemia.
Total normal protein in the CSF is between 15-45 mg/dL, while older adults may have a normal value of up to 70 mg/dL. A value between 45-100 mg/dL may indicate a paraventricular tumor, while a value between 50-200 mg/dL is due to a viral infection. A value more than 500 indicates a bacterial infection or Guillain-Barre syndrome.
Normal lactic dehydrogenase in CSF is 10% of serum level or less than 40 units/L in adults. Lactic dehydrogenase levels exceeding 10% may indicate infection or inflammation of the central nervous system. Excessive levels may also indicate bacterial meningitis, neurosyphilis, or tumors within the brain or spinal cord.
Normal cells in the CSF include 0-5 small lymphocytes/mm3. More than 5 lymphocytes/mm3 may indicate a reaction to an infection, blood, tumor, or chemical substance.
Normal values of glucose detected in the CSF are between 40-70 mg/dL or 60-70% of the blood glucose level. Values less than 18mg/dL are highly suggestive of bacterial meningitis.
Picmonic's rapid review multiple-choice quiz allows you to assess your knowledge.
*Average video play time: 2-3 minutes
Unforgettable characters with concise but impactful videos (2-4 min each)