Introduction
Materials and Methods
PJI is present when one of the major criteria or three out of five minor criteria exist: | ||
Major criteria | (1) Two positive periprosthetic cultures with phenotypically identical microorganism OR (2) A sinus tract communicating with the joint OR | |
Minor criteria | Chronic PJI (>90 days) | |
(1) Elevated serum CRP AND ESR | 10 mg/L 30 mm/hr | |
(2) Elevated SF WBC count OR Changes in the leukocyte esterase strip | 3000 cells/μL + Or ++ | |
(3) Elevated SF PMN% | 80% | |
(4) Positive histological analysis of the periprosthetic tissue | > 5 neutrophil per high-power field in 5 high-power fields (×400) | |
(5) A single positive culture |
Patients | ABX (N = 30) | NO-ABX (N = 76) | p value |
---|---|---|---|
Age (years) | 64.5 (range, 35–91) | 65.8 (range, 25–89) | 0.553 |
Gender | 10 women, 20 men | 31 women, 45 men | 0.514 |
Joint (knee/hip) | 21 knees/9 hips | 56 knees/20 hips | 0.809 |
Gram (+) organism (%) | 71% (15/21) | 76% (39/51) | 0.156 |
Culture-negative PJI | 30% (9/30) | 33% (25/76) | 0.172 |
Statistical Analysis
Results
Diagnostic | ABX group (n = 30) Median (range) | NO-ABX group (n = 76) Median (range) | Difference (95% CI) | p value |
---|---|---|---|---|
Alpha-defensin (S/CO) | 4.2 (1.8–12.8) | 4.9 (0.5–16.8) | 0.68 (−0.98 to 1.26) | 0.451 |
ESR (mm/hr) | 62 (3–140) | 65 (1–140) | 3 (−11 to 22) | 0.252 |
CRP (mg/L) | 25.7 (1.0–302) | 62.0 (3.0–535) | 36.3 (4.0–56.2) | 0.008* |
WBC (cells/μL) | 17,325 (413–104,200) | 29,404 (1100–356,000) | 12,079 (1915–22,650) | 0.008* |
PMN (%) | 87 (3–100) | 92 (40–100) | 5.0 (0.0–7.0) | 0.034* |