Nice my preference however is to make the diagnosis of Hashimoto's Thyroiditis only in presence of antithyroid antibodies. diagnosis is actually clinical or clinico-pathologic correlation. The alternative diagnosis is lymphocytic thyroiditis with a note that correlation is needed. Also to add another comment that sclerosing variant of Hashimoto's can be indistinguishable from Raidel's struma the only way to tell them apart is to demonstrate fibrosis invading the surrounding structures or ask the surgeon if he had a problem removing the thyroid.

----Comment by: savco on 3/5/2008 12:59:22 PM

When was the last time someone diagnosed Riedel's thyroiditis? IS it made here? I'm going to SDR it tomorrow and report back.

----Comment by: Iago on 3/5/2008 9:14:42 PM

Savco - Good points. Riedel thyroiditis is certainly a rare (1.5 ish / 100,000 population incidence ) disease, but it does have interesting histology and morbidity (compressisive symptoms in the throat). Thanks for throwing it up for discussion. Although idiopathic, it is interesting that it also has antithyroid antibodies (like Hashimoto).

----Comment by: PathDoc15 on 3/6/2008 11:18:51 AM

Also agree that a better bottom line would be chronic lymphocytic thyroiditis and if evidence of autoimmune disease exist (eg - antithyroid antibodies) give a c/w Hashmoto's thyroiditis.

----Comment by: PathDoc15 on 3/6/2008 11:25:49 AM

Now we got some learnin' going on! - thanks for the comments. Also, I found a recent excellent picture of the sclerosing variant of Hashimoto's at www.surgicalpathologyatlas.com.

----Comment by: PathDoc15 on 3/6/2008 11:33:39 AM

From a cytopath perspective, we also like to see extensive Hurthle cell metaplasia along with the germinal centers to consider a diagnosis of Hashimoto's. Our bottom line is still "Chronic lymphocytic thyroiditis with features suggestive of Hashimoto's thyroiditis. Correlation with clinical and imaging data suggested."

----Comment by: BigDaddy on 3/21/2008 10:04:49 AM