Subacute Thyroiditis: A Rare Cause of Pyrexia of an Unknown Origin.

Subacute thyroiditis is inflammation of the thyroid gland, classically presenting with neck pain or discomfort and sometimes with associated diffuse tender goiter and overt hyperthyroid symptoms. Only a few rare cases of subacute thyroiditis presenting as pyrexia of unknown origin (PUO) without any of the aforementioned clinical features have been reported in the literature. A 62-year-old male, with a past history of diabetes mellitus, presented with a history of intermittent fever lasting for one month duration. He did not have any significant localizing symptoms, except for a mild headache, and his examination findings were unremarkable as well. Investigations revealed a high erythrocyte sedimentation rate (ESR), high C-reactive protein (CRP) levels, and a deranged thyroid profile, with high free T3 and T4 and suppressed thyroid-stimulating hormone (TSH) levels, suggestive of subacute thyroiditis. The diagnosis was further reinforced by the findings of a supportive ultrasound scan of the neck. The patient was started on steroids, to which he showed a significant clinical and biochemical response. Here, we aim to highlight atypical presentations of subacute thyroiditis and the importance of early consideration of endocrine diseases in the workup of PUO, sometimes even in the absence of suggestive clinical features.

Misleading Free Thyroxine (FT4): A Case Report

@#Interpretation of thyroid function test (TFT) is often straightforward but in certain scenarios, discordance between the clinical impression and the laboratory results exists. A 50-year-old woman with a ten years history of hypothyroidism on levothyroxine presented with a recent notable change in TFT [elevated free thyroxine (FT4) and thyroid-stimulating hormone (TSH)], in an otherwise clinically euthyroid and previously stable TFT, leading to levothyroxine being withheld. This case report highlights the possibility of assay interference as a cause of discordant TFT. It also draws the importance of close collaboration between clinicians and the laboratory to avoid unnecessary investigations and inappropriate management of such a case.