The Thyroid Gland and Its 

 Diseases 



Clinical Syndromes 

 Tests for Thyroid Disorders 



EMIL GOETSCH 



BROOKLYN 



Introduction 



The importance of having specific clinical tests as aids in the diag- 

 nosis and differentiation of that large and obscure group of diseases due 

 to disorders of the endocrin glands is apparent. Of all the ductless glands 

 the active principle or the specific secretion of the thyroid gland is per- 

 haps the best understood. The clinical evidences of over- or under-activity 

 of the thyroid have been known and recognized for a considerable time, 

 and more recently great strides have been made in our knowledge con- 

 cerning the physiological effects of thyroid secretion. It is desirable to 

 know what the properties of the specific secretion of a gland are and 

 what the clinical manifestations most likely would be if this secretion 

 be present in excessive or diminished amounts, before we can hope to 

 apply a clinical test for disturbances in the function of a gland, and hence 

 in the character and amount of its secretion. It was not long after we 

 learned of the action of thyroid secretion that tests for evidences of its 

 presence in increased or diminished amounts were forthcoming, and subse- 

 quently served as aids in the recognition of clinical states of hypo- or hyper- 

 thyroidism. 



There is a great deal of evidence now available which indicates that 

 thyroid secretion has at least three very definite functions upon which 

 are based three of the recent and most valuable tests for thyroid 

 disorders. Some of the older, less practical and hence less valuable tests 

 were doubtless in several instances based upon these same facts, although 

 the underlying explanation was not recognized. In the first place we 

 know that thyroid secretion has a specific stimulating action upon the 

 sympathetic portion of the autonomic nervous system rendering the latter 



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