Skeletal muscle involvement in Rocky Mountain spotted fever.

A case of Rocky Mountain spotted fever in a 10-year-old boy accompanied by an unusually high degree of myalgia and muscle weakness was presented. On admission to the hospital, his creatine phosphokinase, SGOT, SGPT, and aldolase values were all abnormally high. Rash did not appear until the fourth hospital day. On the same day results of a proteus OX-19 titer of blood were reported as positive (titer 1:320) and intravenous therapy with chloramphenicol was started. The child's condition gradually improved and five months later he had no detectable muscle weakness.