Which is the most definitive diagnostic test for polymyositis and dermatomyositis?

Question

Quizplus · Accepted Answer

Muscle biopsy is the most definitive diagnostic test for polymyositis and dermatomyositis. It allows the examination of muscle tissue under a microscope to detect inflammation and damage, which is characteristic of these conditions. Western blot test and immunofluorescent assay are not specific diagnostic tests for these conditions, and DEXA scan is used to measure bone density and is not relevant in diagnosing polymyositis and dermatomyositis.

Which Is the Most Definitive Diagnostic Test for Polymyositis and Dermatomyositis