Objective. The aim of this prospective study was to compare the clinical value of the erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and white blood cell (WBC) count in diagnosis and follow-up of acute hematogenous osteomyelitis in children.
Design. Forty-four children aged 2 weeks to 14 years with bacteriologically confirmed acute hematogenous osteomyelitis were examined. Staphylococcus aureus was responsible in 39 cases (89%), Haemophilus influenzae type b in 3 cases (7%), pneumococcus in 1 case (2%), and a microaerophilic streptococcus in 1 case (2%). ESR was measured at the time of admission and on days 3, 5, 7, 10, 14, 19, and 29 of treatment, and CRP was measured on the same days as ESR but also on days 2, 9, 12, 17, and 23. WBC count was examined at the time of admission and on days 5, 10, 19, and 29.
Results. ESR was elevated (≥20 mm/h) initially in 92% of the cases; the mean value was 45 mm/h, and the peak values (mean 58 mm/h) were reached on days 3 to 5. After this the levels slowly returned to normal in approximately 3 weeks (mean 18 days). CRP was elevated (>19 mg/L) at the time of admission in 98% of the cases, the mean value being 71 mg/L. The peak CRP value was reached on day 2 (mean 83 mg/L). The decrease was very rapid, normal values being reached within a week (mean 6.9 days). The WBC count was a poor indicator of acute hematogenous osteomyelitis, since only 35% of the children had leukocytosis (WBCs > 12 x 109/L) at the time of admission.
Conclusions. In patients with acute hematogenous osteomyelitis, CRP increased and especially decreased significantly faster than ESR, reflecting the effectiveness of the therapy given and predicting recovery more sensitively than ESR or WBC count.