Silent Thyroiditis-Reply

Abstract

In Reply. —These data from Japan by Tajiri et al, again demonstrate a dramatic difference in the incidence of silent (painless) thyroiditis between geographic locations. Our observation 1,2 that silent thyroiditis is not frequently seen outside Japan and parts of the Great Lakes area of North America has been confirmed by brief reports from Rochester, NY, 3 and Philadelphia. 4 Similarly, a recent study by Freeman et al 5 showing a low incidence of postpartum thyroiditis in the Bronx, NY, contrasts with the Japanese experience in which postpartum thyroiditis is common. 6 Although Nikolai has suggested a recent decrease in the frequency of silent thyroiditis in Wisconsin, 7 the data from Tajiri et al, suggests a continuing problem, at least in Japan. As mentioned in their letter, Toyama and Kumamoto are coastal areas of high iodine intake, as is Osaka, where post-partum thyroiditis is common. 6 The association of silent