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.
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.
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).
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.
From the *Pediatric Infectious Diseases Unit
†Pediatric Orthopedics Unit
‡Microbiology and Infectious Diseases Department, Gregorio Marañón University Hospital, Madrid, Spain.
Accepted for publication December 23, 2017.
The authors have no funding or conflicts of interest to disclose. Both the Pediatric Infectious Diseases Unit and the Pediatric Orthopedics Unit participated a few years ago in a clinical trial studying daptomycin for the treatment of osteomyelitis in children.
Address for correspondence: Jesús Saavedra-Lozano, MD, PhD, Pediatric Infectious Diseases Unit, Gregorio Marañón Hospital, O´Donnell Street, 48-50, 28009 Madrid, Spain. E-mail: email@example.com.