Bone and Joint Infections in Children: Septic Arthritis

Abstract

The pathological invasion of a joint and subsequent inflammation is known as septic arthritis. The knee and hip are the most frequently involved joints. Staphylococcus aureus is the most common cause of septic arthritis in children. An acute onset of illness with an inflamed painful joint and restricted movements and inability to use joint (pseudoparalysis) clinically indicates septic arthritis. The diagnosis is difficult in a neonate or young child where refusal to feed, crying, discomfort during change of diaper (if hip is involved) or attempted joint movement may be the only findings. Fever and other systemic signs may also be absent in neonates. Septic arthritis is diagnosed clinically, supported by appropriate radiological and laboratory investigations. The peripheral blood white cell count is frequently raised with a predominance of polymorphonuclear cells. The acute phase reactants such as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) are often markedly raised. Ultrasonography and MRI are preferred investigations in pediatric septic arthritis. Determination of infecting organism in septic arthritis is the key to the correct antibiotic choice, treatment duration and overall management. Joint aspirate and/or blood culture should be obtained before starting antibiotic treatment. Several effective antibiotic regimes are available for managing septic arthritis in children. Presence of large collections, thick pus, joint loculations and pus evacuating into surrounding soft tissues are main indications for surgical drainage. Joint aspiration can be a practical alternative in case the lesion is diagnosed early, with uncomplicated presentations and superficial joints.

Septic arthritis in children: Updated epidemiologic, microbiologic, clinical and therapeutic correlations

“…In developing African countries, the incidence was reported to be 5e20 cases/100,000 areas. 2,3,18 In Southern Israel, the incidence of SA was reported in a retrospective study describing 40 young children <24 months of age during 1988e1993 and was 7.1 cases/ 100,000. The two main pathogens isolated were K. kingae and Hib (48% and 20% of all isolated pathogens, respectively).…”

“…SA incidence among Bedouin children was higher than among Jewish children (15.4 vs. 8.3/100,000 cases). Staphylococcus aureus was the most commonly isolated pathogen (18,19.5% of all patients), followed by Kingella kingae (10, 5.3%)e(37.5% and 20.8% among culture-positive patients, respectively). The number of children with culture-positive SA that required surgery was higher than those with culturepositive SA treated conservatively (P < 0.001).…”

Delayed treatment of septic arthritis in the neonate

“…[3,4] Surgery makes it possible to get biological samples and then guide the selection of antibiotics according to the causative organisms. It also reduces the intraarticular pressure of the joint, subsequently decreases the risk of complications such as AVN of the bone and permanent cartilage damage.…”

“…At present, consensus has been reached that vancomycin should be an empirical antibiotics for osteomyelitis or septic arthritis if prevalence of methicillin-resistant strains of S aureus (MRSA) in community ≥10% and prevalence of clindamycin-resistant S aureus ≥10%. [3,24] …”

“…At present, surgery and antibiotics are the main options in the management of septic arthritis in children. [3,4] …”