Uhthoff's symptom is seen in:: (A) Multiple sclerosis, (B) Poliomyelitis, (C) Guillain-Barre syndrome, (D) Myasthenia gravis
Answer is A. Heat sensitivity refers to neurologic symptoms produced by an elevation of the body's core temperature. Uhthoff's symptom is the unilateral visual blurring that may occur during a hot shower or with physical exercise. It is also common in Multiple sclerosis. Such heat-related symptoms probably result from transient conduction block. Ref: Harrisons principles of internal medicine, 18th edition, Page: 3398.