The UK’s Medicines and Healthcare products Regulatory Agency called on German devicemaker B. Braun Avitum to update the software and hardware of its hemodialysis machines to address issues with their temperature sensors.

The agency said the company’s Dialog+ hemodialysis machines can pose risks to patients if their temperature sensors fail to work properly. A sensor malfunction could raise or lower the temperature of the dialysis fluid outside of the programmed values — and the device will continue to operate without an alarm about the fluctuation.

The firm was ordered to identify the affected devices and contact the manufacturer of the sensors for a service kit or upgrade, prioritizing devices used at home. It’s expected to complete the updates by June 26, 2020.