 Abnormal laboratory findings seen in patients with Rocky Mountain spotted fever may include a low platelet count, low blood sodium concentration, or elevated liver enzyme levels.Serology testing and skin biopsy are considered to be the best methods of diagnosis.Although immunofluorescent antibody assays are considered some of the best serology tests available, most antibodies that fight against "R. rickettsii" are undetectable on serology tests the first seven days after infection.