Puncture wounds: normal laboratory values in the face of severe infection in diabetics and non-diabetics.

PURPOSE: Using infected puncture wounds as a basis for comparison, we pose the question of whether white blood cell count (WBC) and erythrocyte sedimentation rate (ESR) is lower in diabetic patients with foot infections as compared with nondiabetic patients.

PATIENTS AND METHODS: This case control study consisted of two groups, both with infected puncture wounds of the foot, admitted to a 700-bed urban university teaching hospital between 1985 and 1992. The experimental group contained 77 patients with diabetes mellitus. The control group consisted of 69 patients without diabetes. All subjects received emergent incision and drainage of the affected site.

RESULTS: Results revealed a normal WBC count in 57.6% of patients. The ESR was normal in 36.3% of admissions. More nondiabetic patients presented with normal ESR than diabetic patients (62.3% versus 13.7%, respectively; P < 0.0001). Diabetic patients had a significantly higher mean WBC count and ESR than did nondiabetic patients. Pain was the principal complaint more frequently in nondiabetic patients (92.9% NDM versus 70.1% DM, respectively; P < 0.005). Erythema (72.7% versus 51.4%; P = 0.008), and drainage (36.4% versus 7.1%; P < 0.001) were more common in diabetic patients.

CONCLUSION: We conclude that, while a glaringly elevated WBC count or ESR should alert the clinician to the possibility of infection, normal values should not be relied upon to rule out a serious event.