Management of patients with X-linked hypophosphatemic rickets during Covid-19 pandemic lockdown

To identify a safe pathway for management and treatment of patients with X-linked hypophosphatemic rickets (XLH) during Covid-19 pandemic lockdown.

Twenty-six patients with XLH (age 3.1-25.7 years) were enrolled in Pediatric Endocrine Unit; nine of them were receiving human monoclonal anti-fibroblast growth factor 23 antibody (burosumab) and 17 (pediatric patients, age 9.5-17.9 years, n=7; young-adult patients, age 20.1-25.7 years, n=10) received conventional treatment with inorganic oral phosphate salts and active vitamin D metabolites. A Covid-19 free pathway was addressed for XLH patients receiving burosumab treatment in hospital. XLH patients receiving conventional treatment were followed by phone calls, e-mails, or telemedicine.

All XLH patients receiving burosumab continued the scheduled follow-up and treatment; none of them was infected by Covid-19. Seven XLH patients out of 17 (41%) receiving conventional treatment showed some complication related to the disease itself or its treatment: periapical abscess with gingival fistula was diagnosed in five patients (three children and two young-adults) and treated with antibiotics with complete resolution; one child showed abdominal pain due to the administration of high doses of inorganic oral phosphate salts solved by reducing the dosage, and one child had severe legs pain during deambulation after orthopedic surgery solved with common analgesics.

Covid-19 free pathway was safe and effective to manage XLH patients receiving burosumab. E-health technologies were useful methods to follow XLH patients receiving conventional treatment during Covid-19 pandemic lockdown.