Polymyalgia rheumatica with normal values of both erythrocyte sedimentation rate and C-reactive protein concentration at the time of diagnosis: a four-point guidance

In our Editorial we highlight the possibility that polymyalgia rheumatica (PMR) can have normal values of both erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) concentrations at the time of diagnosis. We reported all the data in the literature about this subset of disease and discussed the most relevant hypotheses about the possibility that these biomarkers can be not raised in an auto inflammatory disease such as PMR. The utility of an ultrasound examination of shoulder and hip girdles and the measurement of other biomarkers in adjunct to ESR and CRP represented other points of discussion. In conclusion, we propose a four-point guidance on how to investigate PMR when normal ESR and CRP coexist.