Polymyalgia rheumatica in patients with ankylosing spondylitis: a report of 5 cases.

To report the cases of 5 elderly male patients with ankylosing spondylitis (AS) who developed polymyalgia rheumatica (PMR).The files of 5 patients with AS who developed PMR were retrospectively reviewed. The demographic, clinical, laboratory characteristics and outcome of these patients were summarized.All 5 patients were male, 65-80 years old at the time of their PMR diagnosis. The diagnosis of AS was made simultaneously based on clinical and radiological data; the age at onset of symptoms retrospectively attributable to AS was 20-40 years in three cases, while in the two other patients it could not be determined. The patients presented with typical symptoms of PMR and responded to steroid treatment. HLA B27 was found in three cases, while HLA DR did not show a consistent pattern.The coexistence of AS and PMR could be more than coincidental. Further screening of both patient populations is needed to assess the true extent of this preliminary observation.