Subacute thyroiditis: An uncommon cause of fever of unknown origin.

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.

INTRODUCTION

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).[1-3]

MATERIALS AND METHODS

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.

RESULTS

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. fine needle aspiration cytology (FNAC) in six patients showed multinucleated giant cells. 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.

CONCLUSION

SAT is not an uncommon entity and may present with FUO. High index of suspicion and symptomatic management with analgesics, beta blockers and sometimes with oral steroid lead to remission with low recurrence rate.