title: Giant cell arteritis or tension-type headache?: A differential diagnostic dilemma.
abstract: Giant cell arteritis (GCA) or Temporal arteritis (TA) is an autoimmune disease and the most common type of vasculitis in the elderly. It causes inflammation of the medium and large arteries in the upper part of the body. GCA is an under-recognized cause of  head aches in the elderly, especially when it presents itself with atypical features, resulting in delayed or incorrect diagnosis. Since GCA is a treatable condition, an accurate diagnosis is crucial to prevent the most serious complication of CGA, permanent vision loss. The diagnosis can be further complicated as GCA may present with features of other painful neurological conditions. The present case is an 81-year-old woman diagnosed with GCA, who initially presented with features similar to tension-type headache. Due to overlapping features of these conditions, the diagnosis of GCA was delayed, resulting in irreversible vision loss. Although previous research highlights diagnostic dilemmas featuring GCA and other disease states, this case is exclusive in describing a unique dilemma where tension-type headache mimics GCA.
authors.affiliation: Parkinson's Clinic of Eastern Toronto and Movement Disorders Centre, Toronto, Canada.
authors.forename: Abdul Qayyum
authors.initials: AQ
authors.lastname: Rana
authors.affiliation: Parkinson's Clinic of Eastern Toronto and Movement Disorders Centre, Toronto, Canada.
authors.forename: Usman
authors.initials: U
authors.lastname: Saeed
authors.affiliation: Oakville Bone Centre, Oakville, Ontario, Canada.
authors.forename: Osama A
authors.initials: OA
authors.lastname: Khan
authors.affiliation: Parkinson's Clinic of Eastern Toronto and Movement Disorders Centre, Toronto, Canada.
authors.forename: Abdul Rehman M
authors.initials: AR
authors.lastname: Qureshi
authors.affiliation: Parkinson's Clinic of Eastern Toronto and Movement Disorders Centre, Toronto, Canada.
authors.forename: Dion
authors.initials: D
authors.lastname: Paul
keywords: Giant cell arteritis; headaches; temporal; tension-type headache; vasculitis; vision loss