975. The Use Procalcitonin as a Predictor of Infections in Post-surgical Spinal Infections
Session: Poster Abstract Session: Clinical Studies of Bacterial Infection
Saturday, October 22, 2011
Room: Poster Hall B1
Background: Post-surgical spinal infections can be difficult to detect using the standard available blood tests (WBC, ESR, CRP). While the sensitivity of these tests is high, the specificity is low, making them poor diagnostic tools to guide treatment decisions, especially in the peri- and immediate post-operative period.

Methods:  In order to understand the effects of spinal surgery in the serum procalcitonin levels, we prospectively measured serum procalcitonin levels in 44 consecutive patients undergoing elective spinal surgery. Levels were measured pre-operatively and 24 hours after surgery. In a separate cohort, we followed 16 patients who returned to the emergency room or the outpatient clinic with complaints suggestive of post-surgical infection (fever, swelling, erythema and/or pain in the surgical site). Patients were evaluated by a neurosurgeon and an infectious diseases specialist. WBC, ESR, CRP and procacitonin were measured prior to antibiotic administration and surgical wound exploration. The diagnosis of infection was determined clinically prior to surgery (by the infectious diseases specialist and the neurosurgeon, both blind to the laboratory values). Confirmation of infection was based on intra-operative cultures and operative findings.

Results: Among patients returning for evaluation for post-surgical spinal infections, procalcitonin had a sensitivity, specificity and positive predictive value of 90%, 83%, and 90%, respectively, performing better than ESR (with values of 90%, 20% and 69%) and CRP (100%, 17% and 64%) respectively as a tool for the diagnosis of early wound infection. All patients diagnosed with post-surgical infections had positive operative cultures.

Conclusion: The accuracy of procalcitonin in predicting the presence of post-operative spinal infections was higher than that of ESR ad CRP, making it a useful marker and adjuvant in treatment decision making. We anticipate that the use of procalcitonin will help predict the likelihood of post-operative spinal infections and its use will result in more effective and less invasive treatment for patients with post-operative spinal infections.

Subject Category: N. Hospital-acquired and surgical infections, infection control, and health outcomes including general public health and health services research

Katharine Cronk, MD, PhD1, Ana Moran, MD2, Omar Gonzalez, MD2 and Nicholas Theodore, MD3, (1)Barrow Neurological Institute, Phoenix, AZ, (2)Arizona Pulmonary Specialists, Phoenix, AZ, (3)Neurosurgery, Barrow Neurological Institute, St. Joseph Hospital, Phoenix, AZ


K. Cronk, None

A. Moran, None

O. Gonzalez, None

N. Theodore, None

Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.