A first aspect of the invention relates to a device for a diagnosis and/or therapy monitoring of inflammatory diseases, such as rheumatoid arthritis. It comprises at least a rest or support device (1) for holding at least one extremity (11) of a person. Thereby, the support device has the task of facilitating the at least one extremity, preferably two extremities, for instance the two hands to be comfortably and immovably placed as long as possible. This support device can be provided with a rest with several accessories, such as indentations, bowl-like recesses, ridges, elastic or non-elastic straps and/or loops, etc. Furthermore, at least an excitation source (2) for at least partially illuminating one extremity at least with a radiation of defined excitation wavelength. Furthermore, at least an image sensor (3) is incorporated for capturing at least a reference signal from the extremity as well as several signals from the regions of medical interest (ROI) of the extremity (11). Moreover, a device according to the invention comprises a comparator for comparing the reference signal with the signals from the regions of medical interest (ROI).