Aims Methotrexate has been used in Juvenile Idiopathic arthritis (JIA) for 80 years and is a first line agent, despite the proliferation of newer therapies. British Society of Paediatric and Adolescent Rheumatology guidelines state that varicella status should be checked in all patients, given the risk of disseminated varicella infection. Immunisation should be considered, though this may delay the onset of treatment. Non-immune patients exposed to chickenpox will require VZIG and patients who develop chickenpox need treatment. The incidence of varicella exposure and infection among these patients is unclear. We set out to investigate the current situation.
Methods A descriptive, cross-sectional, questionnaire study. Local research and audit department approval was obtained. All patients with a diagnosis of JIA being treated with Methotrexate between September 2009 and August 2010 were included. Serological status was identified and patients who were none-immune were contacted to complete a telephone survey on their education and experiences.
Results A total of 67 patients were identified. 33 patients were IgG positive. 20 patients (30%) had not had their serology checked. 14 patients (21%) were IgG negative and were included in the telephone survey. Four could not be contacted. All patients said they had been informed as to the risks of varicella infection while on methotrexate. 60% of patients had received written information. 80% of patients were given details of what to do if they were exposed to or developed varicella. While on methotrexate, one patient was exposed and received VZIG, FIVE (50%) developed varicella. Three of these patients were treated at district hospitals without our involvement and consequently have not had their varicella status rechecked. Two patients treated locally remain IgG negative post infection, despite proven varicella zoster on vesicular fluid PCR and IgM positivity.
Conclusions Departmental weaknesses in patient varicella screening and communication with local hospitals have been identified and need to be addressed to adhere to national guidelines. Education of at risk patients appears to be satisfactory. Incidence of Varicella infection among at risk JIA patients on methotrexate appears common and we recommend adoption of universal vaccination in this cohort.