There has been a significant increase in septic arthritis in children with meningococcal infection, due to a shift to serotype W disease in response to recent vaccine changes, clinicians in WA say.
The introduction of meningococcal C vaccine in 2003 has seen a rise in cases of invasive meningococcal disease caused by the W135 serotype – especially in Indigenous children – with the proportion increasing from 1-5% prior to 2012 to almost half in 2016, according to clinicians at the Perth Children’s Hospital.
Meningococcal W disease was more likely to present with predominant joint symptoms, sometimes without of features of sepsis, they report in the Journal of Paediatrics and Child Health.
Dr Aleisha Anderson and colleagues describe a series of eight paediatric cases of meningococcal serotype W associated arthritis which they say highlights the atypical presentations associated with this serogroup and how this may delay diagnosis and appropriate treatment.
The cases covered children ranging from 10 months to seven years of age, all but one of who were Indigenous Australians, and who required three to five weeks of antibiotic treatment to resolve the infection and joint symptoms.
They focus on one case involving a 10-month old Indigenous infant who presented with fever, lethargy and mild left elbow swelling. After initial treatment with intravenous ceftriaxone and vancomycin he developed progressive elbow swelling with joint effusion, and also new‐onset left knee swelling. He underwent joint washout and received several changes in antibiotic regimen including oral oral cefixime and further IV ceftriaxone.
As with the other cases, he eventually made a complete recovery after several weeks of antibiotics and NSAIDs.
The report authors noted that in many cases the children with septic arthritis had meningococcal W that was not susceptible to penicillin, but all were susceptible to ceftriaxone. They said it was notable that long term outcomes after antibiotic therapy were good, with no deaths or readmissions.
The cases highlighted the need for clinician awareness of meningococcal arthritis, and also the difficult of selecting appropriate antibiotic therapy for joint penetration in the absence of guidelines, they said.
“There are several challenges surrounding the management of children with [invasive meningococcal disease] and associated joint involvement,” they wrote.
“Differentiating joint pathology due to direct bacterial invasion from immune‐mediated phenomena may be difficult. Discriminating features suggested from previous studies for meningococcal septic arthritis or immune‐mediated phenomena include timing of onset of joint sign/symptoms (early vs. late), number of joints involved (oligoarticular vs. polyarticular), response to treatment (antibiotics vs. non‐steroidal anti‐inflammatories) and microbiology of joint fluid (culture/PCR positive vs. negative). There are however no validated criteria for distinguishing between the two entities and a spectrum of disease may exist.”
The report authors said the ongoing cases also showed need for all children to receive the recommended meningococcal ACWY vaccine that has been available and government funded since early 2018 for children and adolescents, they said.