Recognize the clinical and laboratory characteristics of giant cell arteritis.

Explanation:       

Unilateral headache in an elderly patient who may also develop some visual problems should always suggest GCA.

It is probably the only indication for an urgent ESR check. ESR could be elevated. Almost always over 50 and if not diagnosed for long, nearing 100 or more.

Immediately start high dose steroids-minimum of 60 mg prednisone a day.Do not wait for performing tests or for results of tests otherwise patient may become blind due to AION (anterior ischemic optic neuropathy)

A temporal artery biopsy consisting of 4 cm of the temporal artery should be performed within 4 days and remember that lesions may be skip lesions (it is like Crohn's disease of the artery!)

There is an overlap between PMR (Polymyalgia Rheumatica) and GCA in about 40% of patients. Remember that GCA needs higher doses of steroids than plain PMR.