Recurrent multifocal active Charcot neuro-osteoarthropathy in a young woman with childhood-onset type 1 diabetes mellitus: a case report

Active Charcot neuro-osteoarthropathy (CNO) is an inflammatory and destructive disorder of bones, joints and soft tissues occurring in the setting of peripheral neuropathy. Although diabetes mellitus is the leading cause in most contemporary series, CNO is not exclusive to diabetes mellitus and can occur in other neuropathic disorders, including leprosy. Recurrent multifocal disease, particularly with extra-foot involvement, is uncommon. We report the case of a young woman with childhood-onset type 1 diabetes mellitus who developed three anatomically distinct episodes of active CNO over seven years. The patient had type 1 diabetes mellitus diagnosed at 5 years of age and longstanding unstable glycaemic control. In 2017, at the age of 25 years and during pregnancy, HbA1c decreased from 12.0% to 7.2% over 6 weeks. At 24 weeks' gestation, after a reported minor right ankle/foot injury, she developed persistent swelling of the right foot and ankle. Radiographs and postpartum magnetic resonance imaging (MRI) showed active destructive right midfoot CNO, most consistent with Sanders-Frykberg zone III and Eichenholtz stage 1. Offloading was prescribed, but adherence was suboptimal and progressive deformity ultimately required right transtibial amputation 2 years later. Two weeks postpartum, while the first episode was still active and before the later amputation, she presented with a painless, warm, swollen left knee. Computed tomography demonstrated severe tibial plateau fragmentation and collapse consistent with active CNO of the knee. Total knee arthroplasty was performed 2 months later, followed by 3 months of rehabilitation and recovery of a satisfactory gait. In 2024, after end-stage kidney disease, 2 years of haemodialysis, living-donor kidney transplantation, belatacept treatment and a short prednisone taper (60 mg/day for 3 days, 40 mg/day for 3 days and 20 mg/day for 3 days), she developed a third episode involving the left foot/ankle. MRI supported active CNO of the medial midfoot/hindfoot, and treatment with a non-removable cast was initiated. This case highlights that active CNO may occur at a young age in people with childhood-onset type 1 diabetes mellitus and may recur sequentially at multiple sites, including the knee. Trauma, abrupt improvement in glycaemia, altered weight-bearing during an active contralateral episode, postpartum biomechanical factors, and post-transplant bone and immune changes were plausible contributors in this patient; however, a single case cannot establish causality. The main clinical message is the need for early recognition, prompt offloading, careful functional rehabilitation and lifelong surveillance in high-risk patients. Long-term prevention should also include sustained achievement of individualised glycaemic targets to reduce neuropathic and microvascular risk, with carefully planned and monitored correction in people with marked chronic hyperglycaemia.