Acute suppurative inflammation of an unchanged thyroid gland is usually defined as thyroiditis. The same lesion of the goiter transformed thyroid parenchyma is called strumitis. In clinical practice, strumites are much more common than thyroiditis. Acute purulent inflammation of the thyroid gland caused by a nonspecific infectious agent is a very rare surgical disease.  

Thyroiditis or strumitis is more often purulent, much less often non-purulent; the latter is sometimes called simple. As a rule, the inflammatory process extends to the entire thyroid gland, less often it affects the right, even less often the left lobe and the isthmus. Inflammation is characterized by diffuse pitrophilic infiltration of the entire thyroid parenchyma, sometimes an abscess forms in a limited area, which usually reaches a significant size and more often has the structure of multiple small-cell pustular foci. In conditions of suppuration of the inflammatory focus in the thyroid gland, as D. Higbee notes, most often, multiple small abscesses appear first, which can later turn into an abscess. 
  

Macroscopically, in acute strumitis or thyroiditis, the thyroid gland is significantly enlarged, dense, sharply subcover. With severe inflammatory phenomena, both the parenchymal elements of the gland and the connective tissue base are involved in the pathological process. 

At microscopic examination of the affected areas thyroid a marked hyperaemia of the blood vessels and infiltration foci thyroid parenchyma segmented leukocytes, sometimes with symptoms of purulent fusion and necrosis of organ tissue. Thyroid epithelial cells surrounding the inflammatory focus clearly proliferate, forming fields of cellular symplasts.  

The follicular structure of the thyroid gland in acute purulent thyroiditis or strumitis is sharply violated, the number of intrafollicular colloid in the follicular cavities decreases and gradually disappears. In this disease, the interstitial connective tissue of the thyroid gland is also affected by leukocyte infiltration. In this case, there is also a pronounced proliferation of cellular elements of the stroma. 

Sometimes extensive abscesses spread and open into the mediastinum and trachea, forming fistulas. Due to acute purulent inflammation of the thyroid gland, the coarse-fibrous fibrous connective tissue grows in excess, in places with signs of hyalinosis and foci of calcification, which leads to a decrease in the mass of the incremental thyroid parenchyma. As noted by R. K. Islambekov and L. M. Platonova, acute purulent nonspecific stromitis and thyroiditis can sometimes be complicated by hypothyroidism and myxedema.