Acute suppurative thyroiditis (AST) is a rare condition. The following factors are thought to make the thyroid relatively resistant to infection: the thyroid capsule, its rich blood supply and lymph drainage and its high iodine concentration. 1 The usual presentation of AST is with neck pain, fever, elevated white cell count (WCC), elevated ESR and at times hyperthyroidism, making it initially difficult to clinically distinguish from subacute thyroiditis (SAT), although patients with AST are often systemically unwell while those with SAT less so. SAT (also known as de Quervain's or granulomatous thyroiditis) is a much more common, self-limiting condition that may require treatment with anti-inflammatory drugs or glucocorticoids.Acute suppurative thyroiditis has a reported mortality of 3.7%-9% 2,3 and therefore it is crucial to make a timely diagnosis. Due to its low incidence, our knowledge of AST is based on isolated case reports, small case series, two reviews over the past 90 years (describing the literature from 1900-1980 by Berger et al and 1980-1997 by Yu et al) 2,3 and one expert opinion guideline. 4 The purpose of this paper is to report 2 unpublished cases, and to perform a systematic review of reported cases over the past 20 years of the epidemiology, clinical features, investigations, management