Kingella kingae as the Main Cause of Septic Arthritis: Importance of Molecular Diagnosis.

BACKGROUND: Kingella kingae is an emergent pathogen causing septic arthritis (SA) in children.The objective of this study was to analyze the etiology of SA in children before and after the implementation of universal 16S rRNA gene polymerase chain reaction and sequencing (16SPCR) in synovial fluid. METHODS: Children ≤14 years with acute SA from a Madrid cohort (2002-2013) were reviewed. Differences in etiology were analyzed before (period 1) and after (period 2) the implementation of bacterial 16SPCR in 2009. A comparison in epidemiology, clinical syndromes, therapy and outcome between infections caused by K. kingae and other bacteria was performed. RESULTS: Bacteria were detected from 40/81 (49.4%) children, with a higher proportion of diagnosis after 16SPCR establishment (period 2, 63% vs. period 1, 31.4%; P = 0.005). The main etiologies were Staphylococcus aureus (37.5%) and K. kingae (35%), although K. kingae was the most common microorganism in P2 (48.3%). Children with K. kingae SA were less likely to be younger than 3 months (0 vs. 42.3%; P < 0.001), had less anemia (21.4 vs. 50%; P = 0.010), lower C-reactive protein (3.8 vs. 8.9 mg/dL; P = 0.039), less associated osteomyelitis (0 vs. 26.9%; P = 0.033), shorter intravenous therapy (6 vs. 15 days; P < 0.001), and had a nonsignificant lower rate of sequelae (0 vs. 30%; P = 0.15) than children with SA caused by other bacteria. However, they tended to have higher rate of fever (86 vs. 57%; P = 0.083). CONCLUSIONS: K. kingae was frequently recovered in children with SA after the implementation of bacterial 16SPCR, producing a milder clinical syndrome and better outcome. Therefore, the use of molecular techniques may be important for the management of these children.

Complications and associated risk factors at screw removal in slipped capital femoral epiphysis treated by cannulated stainless steel screws.

PURPOSE: The aim of our study is to report our complication rate and analyze the associated risk factors when removing cannulated stainless steel screws for SCFE fixation. METHODS: This was a multicenter retrospective study of patients who underwent removal of cannulated stainless steel screws after a mean time of 2.03 years of implantation. Thirty-two patients were included (38 hips) with a mean of 13.7 years of age during screw removal surgery. The mean post-removal follow up time was 1.6 years. In all cases the removal of screws was done systematically. Demographic data, possible risk factors related to removal failure, as well as post-removal complications such as post-removal fractures, infections and scar issues were recorded. RESULTS: A removal failure rate of 15.79 % (6/38) was found. The removal surgical time was longer than the initial fixation time but without statistical significance (70.78 vs 61.84 m, p = 0.196). However, the duration of screw implantation (r (2): 7.09; IC: 1.12-13.06) and screw head bony coverage (r (2): 21.32; IC: 5.58-37.06) were both related to this prolonged time. Multivariant analysis revealed that a fully threaded cannulated screw had the lowest removal failure risk (OR: 0.3; IC: 0.14-0.61). There were no postremoval complications recorded. CONCLUSIONS: We recommend to use full threaded cannulated stainless steel screws and to perform the procedure as soon as the physis are closed to decrease the surgical time. It is a safe procedure based on a low rate of complications such as post-removal fractures, infection and scar issues.