subacute thyroiditis ( sat ) is a self - limited , possibly viral , inflammatory thyroid disorder usually associated with thyroid pain and systemic symptoms . there are few case reports of presentation of sat as fever of unknown origin ( fuo).[13 ] this is a retrospective analysis of 12 patients of sat , presenting in a tertiary care hospital of eastern india from april 2010 to july 2012 . we describe the clinical presentation , investigation , management , and outcome of the patients with sat . twelve patients ( seven males and five females ) were diagnosed with sat with mean age of presentation 51 years ( range 45 - 60 years ) . fever of more than 3 weeks satisfying the definition of fuo was found in 10 ( 83.3% ) patients . neck pain and tenderness were found in 11 out of 12 patients ( 91.6% ) . one had presented with acute fever with erythema over the neck mimicking acute infective thyroiditis . five patients were newly diagnosed with diabetes mellitus , and one had impaired fasting , and one impaired glucose tolerance . markers of inflammation like raised erythrocyte sedimentation rate ( esr ) and crp , ultrasonography ( usg ) features suggestive of thyroiditis and no uptake in thyroid scan were found in all cases . analgesics and beta blockers were given to all patients , and 8 ( 66.6% ) of them required steroids to alleviate the severe symptoms . recurrence of the illness was found in only 2 ( 16.6% ) individuals , after stopping the steroid . seven patients ( 58.3% ) developed subclinical or overt hypothyroidism at 3 months of follow - up . high index of suspicion and symptomatic management with analgesics , beta blockers and sometimes with oral steroid lead to remission with low recurrence rate .
subacute thyroiditis ( sat ) is a self - limited , possibly viral , inflammatory thyroid disorder usually associated with thyroid pain and systemic disorder 
 . sat is not uncommon and can present with pyrexia of unknown origin . 
 high index of suspicion is required and cases are managed symptomatically .