Interleukin-6 in two-stage revision arthroplastyS. Hoell, L. Borgers, G. Gosheger, R. Dieckmann, D. Schulz, J. Gerss, J. Hardes
Ankle Elbow Hip Knee Shoulder Wrist
The purpose of this study was to evaluate whether the serum level of interleukin 6 (IL-6) could be used to identify the persistence of infection after the first stage of a two-stage revision for periprosthetic joint infection.
Between 2010 and 2011, we prospectively studied 55 patients (23 men, 32 women; mean age 69.5 years; 36 to 86) with a periprosthetic joint infection. Bacteria were identified in two intra-operative tissue samples during re-implantation in 16 patients. These cases were classified as representing persistent infection.
To calculate a precise cut-off value which could be used in everyday clinical practice, a 3 x 2 contingency table was constructed and manually defined.
We found that a serum IL-6 ≥ 13 pg/mL can be regarded as indicating infection: its positive-predictive value is 90.9%. A serum IL-6 ≤ 8 pg/mL can be regarded as indicating an absence of infection: its negative predictive value is 92.1%.
The serum IL-6 level seems to be a reasonable marker for identifying persistent infection after the first stage of a revision joint arthroplasty and before attempting re-implantation.