Characteristics of children with acute lymphoblastic leukemia presenting with arthropathy.

Acute lymphoblastic leukemia (ALL) is the most common childhood neoplasia and may present with arthralgia and arthritis, with the risk of misdiagnosis and diagnostic delay. We describe in detail arthropathy (arthritis/arthralgia) among children with leukemia as the children's laboratory results, misdiagnosis, and treatment before the diagnosis of ALL and the diagnostic delay. In this retrospective cohort study, we reviewed records of 286 children aged 1-15 years diagnosed with ALL from January 1992 to March 2013. We identified 26 children with arthralgia and 27 children with arthritis. The majority of the children had one or two joints involved (arthralgia 72%, arthritis 42%), and most often hips and knees. Morning stiffness was not reported. Imaging of affected joints was included in the initial workup of 77% of children with ALL and arthropathy, and 66% was abnormal. Misdiagnosis as JIA occurred in 26% and 71% of these children received treatment with intraarticular corticosteroids. The diagnostic delay was 3 weeks longer for the children with arthritis than those with arthralgia (median 54 vs 36 days), primarily as a consequence of a longer first doctor's delay. Compared to the children with arthralgia, the children with arthritis were more often misdiagnosed and treated with intraarticular steroid before the diagnosis of ALL. They also had longer diagnostic delay, primarily as a consequence of a longer first doctor's delay.