First documented outbreak of arthritis caused by Kingella kingae in a Spanish childcare center

Abstract

Background: Recently, Kingella kingae (K. kingae) has been described as the most common agent of skeletal system infections in children 6 months-2 years of age. More exceptional is the clinical presentation in clusters of invasive K. kingae infections. We describe the investigation of the first outbreak of 3cases of arthritis caused by K. kingae documented in Spain detected in a daycare center in Roses, Girona.

Patients and methods: In December of 2015 surveillance throat swabs obtained from all attendees from the same class of the index daycare center were assessed to study the prevalence of K. kingae colonization. The sample was composed of 9 toddlers (range: 16-23 months of age). Investigation was performed by culture and K. kingae-specific RT-PCR. Combined amoxicillin-rifampicin prophylaxis was offered to all attendees who were colonized by K. kingae. Following antimicrobial prophylaxis, a new throat swab was taken to confirm bacterial eradication.

Results: K. kingae was detected by RT-PCR throat swabs in the 3index cases and 5of the 6daycare attendees. Cultures were negative in all cases. After administration of prophylactic antibiotics, 3toddlers were still positive for K. kingae-specific RT-PCR.

Conclusions: Clusters of invasive K. kingae infections can occur in daycare facilities and closed communities. Increased awareness and use of sensitive detection methods are needed to identify and adequately investigate outbreaks of K. kingae disease. In our experience, the administration of prophylactic antibiotics could result in partial eradication of colonization. No further cases of disease were detected after prophylaxis.

Keywords: Brote; Daycare centers; Guardería; Infecciones osteoarticulares; Kingella kingae; Osteoarticular infections; Outbreak; Public health; Salud pública.