Patients with rheumatic fever often do not have elevated rheumatoid factor levels, as rheumatic fever primarily follows a streptococcal infection. There is typically an increase in anti-streptolysin O antibodies, while rheumatoid factors are often negative. In addition to elevated anti-streptolysin O, patients with rheumatic fever may also experience valvular heart disease, most commonly mitral stenosis. Some patients may present with skin erythema and symptoms similar to chorea, which leads us to consider the possibility of rheumatic fever. The treatment of rheumatic fever primarily involves regular antibiotic therapy and continued administration of intramuscular benzathine penicillin for a period of time. (The use of medications should be under the guidance of a professional doctor.)