Work

Culture-Negative Septic Arthritis in Children

Year: 2016

Type: article

Abstract: Background. Choice of empiric antibiotic therapy for septic arthritis (SA) children is challenging given the frequency of negative clinical cultures. Kingella kingae is an increasingly important cause of SA in young children (<5 yr) but rarely grows on standard agar plates. We aimed to describe culture-negative septic arthritis (CNSA) in children and assess treatment failure rates among those who received agents active (cephalosporins) and variably or not active (clindamycin, oxacillin, vancomycin) against K. kingae. Methods. Retrospective cohort study of patients <19 yr hospitalized with SA at the Children's Hospital of Philadelphia from January 2002 to December 2014. SA was defined as joint WBC >20,000 with associated symptoms or positive joint fluid culture; CNSA was as above with negative cultures and no pretreatment. Children with hospital transfer, ICU admission, positive Lyme serology, sickle cell disease, immunodeficiency, or hardware at the site of infection were excluded. Treatment failure was defined as change in antibiotics due to clinical worsening or lack of improvement in >48 h. Results. Of 221 SA children meeting inclusion/exclusion criteria, median age was 4.1 years, 55% were white, and 48% were female. Joint fluid culture was positive in 26% (10/39) of pretreated and 29% (52/182) of non-pretreated patients (p = 0.71). MSSA (50%, 31/62) and MRSA (18%, 11/62) were the most common pathogens; K. kingae was isolated in 1 patient. 17% (31/182) of SA patients had concomitant osteomyelitis (OM), which was associated with higher CRP and ESR, and longer duration of symptoms (table). Of the 72 patients <5 yr with CNSA without OM, treatment failure rates were 11% (5/44) for clindamycin, 9% (1/11) for vancomycin, 20% (1/5) for oxacillin, and 0% (0/12) for cephalosporins. Conclusion. Patients with concomitant OM had longer duration of symptoms and higher inflammatory markers. Antibiotics with variable or no activity against K. kingae were most often used to treat CNSA in children <5 yr and failed in >10% of cases. Disclosures. K. Downes, Merck & Co: Investigator, Research grant Pfizer Inc.: Investigator, Research grant

Source: Open Forum Infectious Diseases

DOI: 10.1093/ofid/ofw172.840