Comparisons of eccrine sweat gland anatomy in genetic, chromosomal, and other diseases, and a suggested procedure for use of sweat gland measurements in differential diagnosis.

Statistical analysis of the dimensions of microdissected eccrine sweat glands (duct length, coil volume, ratio of coil volume to duct length, and axis ratio of coil) was performed for several diseases (cystic fibrosis of the pancreas, Werdnig-Hoffmann disease, tetralogy of Fallot, chronic renal disease, and trisomies 13, 18, and 21) using both individual and grouped age-matched control patients. Duct length, coil volume, and the ratio of the two all rise with age. Eccrine gland duct length was found to be significantly large in tetralogy of Fallot and Werdnig-Hoffmann disease and small in chronic renal disease (less so in males than in females, trisomy 13 and trisomy 18). Secretory coil volume was significantly smaller than normal in trisomy 21 (Down syndrome) and in chronic renal disease, and the ratio of coil volume to duct length was low in trisomy 21 and chronic renal disease. The shape of the secretory coil (axis ratio) was possibly abnormal in trisomy 13. Gland dimensions were normal for cystic fibrosis. Using the multivariate procedure of discriminant analysis, it was found that sweat gland measures significantly contributed to the differentiation of diseases, after adjustments were made for variations in age-at-death. This suggested the possibility that criteria for distinction of clinically similar genetic, metabolic, or chromosomal diseases by study of the anatomic properties of eccrine glands obtained by skin biopsy could be developed. A procedure of analysis comparing the "percentage of normal" of gland dimensions for each disease to control values, and thereby differentiating disease categories on the basis of the "percentage of normal" values, is presented.