Polymyalgia rheumatica and Giant Cell Arteritis - Update on Diagnosis and Therapy Abstract. Polymyalgia rheumatica (PMR) is an inflammatory syndrome which often co-incides with giant cell arteritis (GCA). Due to unspecific symptoms and a plethora of possible alternative diagnoses, PMR often represents a diagnostic challenge. The use of ultrasound, but also other imaging methods has improved and accelerated the time to diagnosis in PMR and GCA, so that complications such as blindness can be reduced. Glucocorticoids are still the main initial therapy for both diseases. Although further research is needed concerning prevention of and screening for long term complications for GCA, the efficacy of biologicals, namely tocilizumab, has markedly increased therapeutic options for GCA and allows for a reduction of side effects.