Rapid plasma reagin

Background

• Non-treponemal diagnostic test for syphilis
• Used to trend titres in response to treatment

Interpretation

• Reported as the greatest dilution that is still positive

False positive

• Infectious
  • Bacterial endocarditis, including rheumatic heart disease
  • Chancroid
  • Varicella-zoster virus
  • Epstein-Barr virus
  • Leprosy
  • Lymphogranuloma venereum
  • Malaria
  • Mumps
  • Mycoplasma pneumoniae
  • Streptococcus pneumoniae
  • Rickettsioses
  • Tuberculosis
  • Viral hepatitis
  • Viral pneumonia
  • Other treponemal infections such as yaws, pinta, or bejel
• Non-infectious
  • Older age
  • Chronic liver disease
  • Connective tissue diseases such as rheumatoid arthritis
  • Injection drug use
  • Malignancy
  • Multiple myeloma
  • Pregnancy
  • Ulcerative colitis