A device for detecting moisture for an arrangement for monitoring an access to a patient for a system by which, via a flexible line, a liquid is fed to and/or out from the patient, for monitoring the vascular access in extra-corporeal blood treatment and for monitoring a central venous access in acute dialysis, an arrangement for monitoring an access to a patient, and a method of producing a device for detecting moisture for connection to a monitoring arrangement are described. The device for detecting moisture is characterized in that at least a part or portion of the device takes the form of a resilient attaching element having parts which fit round a flexible line and/or a system for connecting a flexible line. The attaching element, which is formed after the fashion of a clip, allows the device for detecting moisture to be attached quickly and securely to a flexible line.
