Diagnostic Considerations

Syphilis, a reportable disease, is tracked by the Centers for Disease Control and Prevention (CDC). Syphilis has an extensive differential diagnosis. In particular, the extremely variable manifestations of tertiary syphilis produce an extremely broad differential diagnosis, and care must be taken to consider syphilis in cardiac, dermatologic, and neurologic disorders as is relevant. Patients diagnosed with syphilis should also be tested for other sexually transmitted diseases (STDs), including chlamydia, gonorrhea, trichomoniasis, bacterial vaginosis, and HIV infection.

When making a primary diagnosis of a generalized rash or an STD, always include syphilis in the differential diagnoses because of its varying manifestations.

Differential Diagnoses

Workup

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Media Gallery

Syphilis. These photographs depict the characteristic chancre observed in primary syphilis. Used with permission from Wisdom (Left) A. Color Atlas of Sexually Transmitted Diseases. Year Book Medical Publishers Inc; 1989. (Right) Centers for Disease Control and Prevention
Syphilis. These photographs show the disseminated rash observed in secondary syphilis. Used with permission from Wisdom A. Color Atlas of Sexually Transmitted Diseases. Year Book Medical Publishers Inc; 1989.
Syphilis. These photographs show close-up images of gummas observed in tertiary syphilis. Used with permission from Wisdom A. Color Atlas of Sexually Transmitted Diseases. Year Book Medical Publishers Inc; 1989.
Syphilis. This photograph depicts primary syphilis "kissing" lesions. Used with permission from Wisdom A. Color Atlas of Sexually Transmitted Diseases. Year Book Medical Publishers Inc; 1989.
Syphilis. Palmar lesions observed in secondary syphilis. Used with permission from Wisdom (Left) A. Color Atlas of Sexually Transmitted Diseases. Year Book Medical Publishers Inc; 1989. (Right) Centers for Disease Control and Prevention
These photographs illustrate examples of condylomata lata. The lesions resemble genital warts (condylomata acuminata). Fluids exuding from these lesions are highly infectious. Used with permission from Wisdom A. Color Atlas of Sexually Transmitted Diseases. Year Book Medical Publishers Inc; 1989.
Syphilis. These photographs illustrate typical facies of congenital syphilis. Used with permission from Wisdom A. Color Atlas of Sexually Transmitted Diseases. Year Book Medical Publishers Inc; 1989.
Syphilis. This photograph shows an example of Hutchinson teeth in congenital syphilis. Note notching. Used with permission from Wisdom A. Color Atlas of Sexually Transmitted Diseases. Year Book Medical Publishers Inc; 1989.
Syphilis. This photograph illustrates chorioretinitis of congenital syphilis. Used with permission from Wisdom A. Color Atlas of Sexually Transmitted Diseases. Year Book Medical Publishers Inc; 1989.
Syphilitic chancre
Secondary syphilis - Exanthem
Secondary syphilis - Exanthem
Lues hematoxylin and eosin stain. Histopathological examination shows a lichenoid infiltrate that is stereotypical of the secondary stage of syphilis. Note that vacuolar alteration of the superjacent epithelium can be seen much like a noninfectious form of lichenoid dermatitis. The subjunctional infiltrate is rich in histiocytes and plasmacytes. At times, an overtly granulomatous lichenoid infiltrate can be seen.
Lues TP stain. Immunoperoxidase staining for T pallidum highlights many slender coiled organisms residing in the perijunctional zone. Occasionally, organisms can also be found in the upper dermis or around adnexal structures.

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Author

Pranatharthi Haran Chandrasekar, MBBS, MD Professor, Chief of Infectious Disease, Department of Internal Medicine, Wayne State University School of Medicine

Pranatharthi Haran Chandrasekar, MBBS, MD is a member of the following medical societies: American College of Physicians, American Society for Microbiology, International Immunocompromised Host Society, Infectious Diseases Society of America

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

John L Brusch, MD, FACP Assistant Professor of Medicine, Harvard Medical School; Consulting Staff, Department of Medicine and Infectious Disease Service, Cambridge Health Alliance

John L Brusch, MD, FACP is a member of the following medical societies: American College of Physicians, Infectious Diseases Society of America

Disclosure: Nothing to disclose.

Chief Editor

Michael Stuart Bronze, MD David Ross Boyd Professor and Chairman, Department of Medicine, Stewart G Wolf Endowed Chair in Internal Medicine, Department of Medicine, University of Oklahoma Health Science Center; Master of the American College of Physicians; Fellow, Infectious Diseases Society of America

Michael Stuart Bronze, MD is a member of the following medical societies: Alpha Omega Alpha, American College of Physicians, American Medical Association, Association of Professors of Medicine, Infectious Diseases Society of America, Oklahoma State Medical Association, Southern Society for Clinical Investigation

Disclosure: Nothing to disclose.

Additional Contributors

Daniel J Hogan, MD Clinical Professor of Internal Medicine (Dermatology), Nova Southeastern University College of Osteopathic Medicine; Investigator, Hill Top Research, Florida Research Center

Daniel J Hogan, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Dermatology, American Contact Dermatitis Society, Canadian Dermatology Association

Disclosure: Nothing to disclose.

Daniel R Lucey, MD, MPH, MD, MPH

Daniel R Lucey, MD, MPH, MD, MPH is a member of the following medical societies: Alpha Omega Alpha, American College of Physicians

Disclosure: Nothing to disclose.

Eric L Weiss, MD, DTM&H Medical Director, Office of Service Continuity and Disaster Planning, Fellowship Director, Stanford University Medical Center Disaster Medicine Fellowship, Chairman, SUMC and LPCH Bioterrorism and Emergency Preparedness Task Force, Clinical Associate Professor, Department of Surgery (Emergency Medicine), Stanford University Medical Center

Eric L Weiss, MD, DTM&H is a member of the following medical societies: American College of Emergency Physicians, American College of Occupational and Environmental Medicine, American Medical Association, American Society of Tropical Medicine and Hygiene, Physicians for Social Responsibility, Southeastern Surgical Congress, Southern Oncology Association of Practices, Southern Clinical Neurological Society, Wilderness Medical Society

Disclosure: Nothing to disclose.

Joseph J Sachter, MD, FACEP Consulting Staff, Department of Emergency Medicine, Muhlenberg Regional Medical Center

Joseph J Sachter, MD, FACEP is a member of the following medical societies: American Academy of Emergency Medicine, American College of Emergency Physicians, American Association for Physician Leadership, American Medical Association, Society for Academic Emergency Medicine

Disclosure: Nothing to disclose.

Timothy McCalmont, MD Director, UCSF Dermatopathology Service, Professor of Clinical Pathology and Dermatology, Departments of Pathology and Dermatology, University of California at San Francisco; Editor-in-Chief, Journal of Cutaneous Pathology

Timothy McCalmont, MD is a member of the following medical societies: Alpha Omega Alpha, American Medical Association, American Society of Dermatopathology, California Medical Association, College of American Pathologists, United States and Canadian Academy of Pathology

Disclosure: Received consulting fee from Apsara for independent contractor.

Richard H Sinert, DO Professor of Emergency Medicine, Clinical Assistant Professor of Medicine, Research Director, State University of New York College of Medicine; Consulting Staff, Vice-Chair in Charge of Research, Department of Emergency Medicine, Kings County Hospital Center

Richard H Sinert, DO is a member of the following medical societies: American College of Physicians, Society for Academic Emergency Medicine

Disclosure: Nothing to disclose.

Paul Krusinski, MD Director of Dermatology, Fletcher Allen Health Care; Professor, Department of Internal Medicine, University of Vermont College of Medicine

Paul Krusinski, MD is a member of the following medical societies: American Academy of Dermatology, American College of Physicians, Society for Investigative Dermatology

Disclosure: Nothing to disclose.

Richard P Vinson, MD Assistant Clinical Professor, Department of Dermatology, Texas Tech University Health Sciences Center, Paul L Foster School of Medicine; Consulting Staff, Mountain View Dermatology, PA

Richard P Vinson, MD is a member of the following medical societies: American Academy of Dermatology, Texas Medical Association, Association of Military Dermatologists, Texas Dermatological Society

Disclosure: Nothing to disclose.

Brian Euerle, MD, FACEP Associate Professor, Department of Emergency Medicine, Director of Emergency Ultrasound Program, University of Maryland School of Medicine

Brian Euerle, MD, FACEP is a member of the following medical societies: American Academy of Emergency Medicine, American College of Emergency Physicians, Society for Academic Emergency Medicine

Disclosure: Nothing to disclose.

Maria M Diaz, MD Staff Physician, Department of Emergency Medicine, Parkland Medical Center

Maria M Diaz, MD is a member of the following medical societies: American College of Emergency Physicians, Phi Beta Kappa, Emergency Medicine Residents' Association

Disclosure: Nothing to disclose.