Ross syndrome associated with cytomegalovirus infection.

We report a 40-year-old woman who developed Ross syndrome (impairment of sweating and thermoregulation, tonic pupils, and hyporeflexia) associated with cytomegalovirus (CMV) infection. Her serum CMV IgM and IgG antibody titer levels were elevated. Along with clinical improvement, a gradual decrease of her elevated CMV IgM antibody titer level was seen with a continued increase in her CMV IgG antibody titer level. The CMV IgM antibody titer was also positive in the cerebrospinal fluid.