KCTD12 and bacterial arthritis: Neutrophil collagenase, BTB/POZ domain-containing protein KCTD12, ubiquitin-like modifier-activating enzyme 1, and guanine nucleotide-binding protein subunit beta-2 were upregulated when comparing septic arthritis at PID1 to both eradicated septic arthritis at PID4 and experimentally induced non-septic synovitis at PID1 (Table 3).