Characteristics of patients with septic and crystal-induced arthritis
| Septic arthritis, n=114 | Crystal-induced arthritis, n=104 | P value | |
| Male sex, n (%) | 66 (57.9) | 51 (49) | 0.24 |
| Age (years) | 65.9 (17.2) | 72.3 (15.5) | <0.005 |
| Fever (temperature≥38.5°C), n (%) | 44 (38.6) | 35 (33.7) | <0.005 |
| Comorbidities, n (%)* | 42 (38.3) | 48 (46.1) | <0.005 |
| Bacteria, n (%) | |||
| Staphylococcus† | 52 (45.6) | – | |
| Others‡ | 62 (54.4) | – | NA |
| Crystals, n (%) | NA | ||
| MSU | – | 34 (32.7) | NA |
| CPP | – | 70 (67.3) | NA |
| Blood leucocyte count (cells/mm3) | 11 075 (4518) | 9250 (3263) | <0.005 |
| Neutrophil count (cells/mm3) | 8683 (4265) | 6505 (3014) | <0.0005 |
| Eosinophil count (cells/mm3) | 72.7 (84.1) | 144.7 (152.9) | <0.0005 |
| CRP level (mg/L) | 165.1 | 100.5 | <0.0005 |
| Died, n (%) | 3 (2.6) | 0 | <0.005 |
| Eosinophil count≤50 /mm3, n (%) | 62 (54) | 26 (25) | <0.0005 |
Data are mean (SD) unless indicated.
*Diabetes, cancer, haematological malignancies.
†Methicillin-sensitive Staphylococcus aureus (39.5%), methicillin-resistant Staphylococcus aureus (6.1%); coagulase-negative Staphylococci (19.3%).
‡Streptococcus (21%); Gram-negative bacteria (7%); others (7.1%).
CPP, calcium pyrophosphate; CRP, C reactive protein; MSU, monosodium urate.;