TABLE 4.

Causes of false-positive serological tests for syphilis

Nontreponemal tests	Treponemal tests
Advancing age	Advancing age
Bacterial endocarditis	Brucellosis
Brucellosis	Cirrhosis
Chancroid	Drug addiction
Chickenpox	Genital herpes
Drug addiction	Hyperglobulinemia
Hepatitis	Immunizations
Idiopathic thrombocytopenic purpura	Infectious mononucleosis
Immunizations	Leptospirosis
Immunoglobulin abnormalities	Leprosy
Infectious mononucleosis	Lyme disease
Intravenous drug use	Malaria
Leprosy	Pinta
Lymphogranuloma venereum	Pregnancy
Malignancy	Relapsing fever
Measles	Scleroderma
Mumps	Systemic lupus erythematosus
Pinta	Thyroiditis
Pneumococcal pneumonia	Yaws
Polyarteritis nodosa
Pregnancy
Rheumatoid arthritis
Rheumatic heart disease
Rickettsial disease
Systemic lupus erythematosus
Thyroiditis
Tuberculosis
Ulcerative colitis
Vasculitis
Viral pneumonia
Yaws