The 'Starch iodine test' is useful to diagnose:: (A) Wegener's granulomatosis, (B) Cat scratch disease, (C) Sarcoidosis, (D) Frey's syndrome
Answer is D. The 'Starch iodine test' is useful to diagnose Frey's syndrome. This involves painting the affected area with iodine, which is allowed to dry before applying dry starch, which turns blue on exposure to iodine in the presence of sweat. Sweating is stimulated by salivary stimulation.