Miliaria and anhidrosis. 3. Multiple small patches and the effects of different periods of occlusion

Earlier studies reported from our Institute described a technique employing an occlusive polyethylene wrap over large areas of the body for 48 to 72 hours to produce histologically and clinically typical miliaria and long-lasting hypohidrosis. But these large wrappings did not permit simultaneous comparisons of the local effects of different pathogenetic, prophylactic, and therapeutic influences on the same individual. This report describes a multiple occlusive patch method developed to carry out such comparisons on small, isolated test sites, and compares the effects of different periods of occlusion in producing miliaria, post-miliarial hypohidrosis, and concomitant histological changes. Miliaria was produced consistently after 48 hours of occlusion, but not before. This was closely correlated with the first observations of periductal inflammation and the onset of persistent hypohidrosis. No anatomical or physiological antecedent to these pathologic events was identified.