The case is reported of a 75-year-old woman diagnosed with polymyalgia rheumatica (PMR), treated with low doses of prednisone, and with clinical and analytical remission. Two years later, she presented with a clinical picture of giant cell arteritis (GCA), including headache, diplopia, jaw pain, feeling of swelling in both temples, and elevation of acute phase reactants. Symptoms spontaneously subsided two weeks later, while analytical parameters improved without any treatment. A high-resolution color Doppler ultrasound showed thickening of the intima-media complex with “halo” sign in the right temporal artery. A biopsy of the right temporal artery was performed, although it was not successful, as no artery could be found, and the procedure became more complicated with an eyebrow ptosis due to a lesion of the frontal branch of the facial nerve. GCA diagnosis was based on the clinical, laboratory and ultrasound findings. The patient was treated with prednisone and methotrexate, without clinical or analytical relapse. Comments are presented on the described cases of GCA with spontaneous remission and the most appropriate treatment in these cases are discussed. Other peculiarities of the case are also mentioned, such as the progression to GCA more than two years after the onset of PMR, and the complications from the temporal artery biopsy.