In cases of suspected spinal infection, the sensitivity of an elevated WBC count (35-61%), ESR (76-95%) and CRP (82-98%) may help guide further evaluation or consideration of other entities.
Incorporation of ESR/CRP into an ED decision guideline may help differentiate those patients in whom MRI may be performed on a nonemergent basis.
An elevated ESR (>20 mm/hour) also has a role in the diagnostic evaluation of occult malignancy (sensitivity 78%, specificity 67%).
References
Davis DP, Salazar A, Chan TC, Vilke GM. Prospective evaluation of a clinical decision guideline to diagnose spinal epidural abscess in patients who present to the emergency department with spine pain: Clinical article. Journal of Neurosurgery: Spine. 2011;14(6):765-770.
Deyo RA, Diehl AK. Cancer as a cause of back pain. Journal of general internal medicine. 1988;3(3):230-238.
