Computed tomography in the diagnosis of fever of unknown origin: case report.

Fever of unknown origin (FUO) can be a symptom of at least two hundred diseased. Positron emission tomography-computed tomography (PET/CT) is an informative, but not readily available imaging tool. We present a clinical case of giant cell arteritis where computed tomography (CT) played a key role in the diagnosis. A 61-year-old woman presented to the hospital with a nocturnal fever up to 39,5С, chest and scapular pain, weight loss (10 kg in 3 months). Lymphoproliferative and infectious diseases were excluded. Baseline colonoscopy had revealed erosions in the colonic mucosa, and the patient was admitted to the gastroenterology department with the preliminary diagnosis of ulcerative colitis. Follow-up colonoscopy had excluded this diagnosis. Additional imaging via chest and abdominal CT scan revealed wall thickening of aorta and its branches with subtle contrast enhancement. Tuberculous aortoarteritis and syphilitic aortitis were excluded. The patient was diagnosed with giant cell arteritis involving brachiocephalic trunk, subclavian arteries and celiac trunk. Prednisolone was administered with subsequent reduction in symptoms. Despite the fact that CT is not the gold standard for the differential diagnosis of FUO, in this case it assisted in establishing the definitive diagnosis.