Case Eight – August 2017

• 25 year old male presented with widespread reddish-brown papules and patches with involvement of the palms and soles
• A punch biopsy of the left wrist was performed

• Secondary syphilis
• Erythema multiforme

Sections show a perivascular and lichenoid dermatitis with associated lymphocytic exocytosis, acanthosis and hyperkeratosis.

Plasma cells are present within the inflammatory cell infiltrate.

Immunohistochemical stain for Treponema pallidum antigen is positive and highlights the spirochetes within the epidermis.

Secondary syphilis

• Syphilis is an infectious disease caused by the spirochete Treponema pallidum
• Primary syphilis infection presents as an isolated, painless papule that ulcerates (chancre)
  • Associated lymphadenopathy develops about one month later
  • Primary syphilis infection histologically shows ulceration and a dermal infiltrate containing lymphocytes and plasma cells. Blood vessels also often exhibit endothelial swelling.
• Secondary syphilis is seen in the setting of untreated patients about 3 weeks to 3 months after the primary infection and is characterized by a widespread rash that typically involves the palms and soles
  • Condyloma lata presenting as moist, warty patches near genitals and body folds can also be seen during this stage of syphilis infection
  • Condyloma lata resemble other lesions of secondary syphilis histologically but additionally show marked epidermal hyperplasia
• The histology of secondary syphilis can be variable but is typically characterized by a psoriasiform and lichenoid dermatitis with an associated chronic inflammatory infiltrate containing plasma cells
  • Plasma cells may be sparse or absent in up to one third of cases
  • Granulomatous changes can also be seen in late stage secondary syphilis
• Tertiary syphilis develops 3 to 10 years after primary infection
  • Clinical presentations includes gummas (granulomatous lesions with necrosis) and neurosyphilis with infection of the brain and spinal cord
• Silver stains such as Warthin-Starry and an immunohistochemical stain for Treponema pallidum antigen are both techniques to detect spirochetes within formalin fixed tissue specimens
• PCR-based techniques can also be performed on biopsy materials to confirm infection

• Syphilis is an infectious disease caused by the spirochete Treponema pallidum
• Primary syphilis infection presents as an isolated, painless papule that ulcerates (chancre)
• Secondary syphilis is seen in the setting of untreated patients about 3 weeks to 3 months after the primary infection and is characterized by a widespread rash that typically involves the palms and soles
• Tertiary syphilis develops 3 to 10 years after primary infection and can be complicated by neurological involvement
• The histology of secondary syphilis can be variable but is typically characterized by a psoriasiform and lichenoid dermatitis with an associated chronic inflammatory infiltrate containing plasma cells
  • Plasma cells may be sparse or absent in up to one third of cases
  • Granulomatous changes can also be seen in late stage secondary syphilis
• Immunohistochemical stain for Treponema pallidum antigen and PCR-based tests are a more sensitive way to detect spirochetes within formalin fixed tissue specimens than conventional silver stains such Warthin-Starry stain