Case 166. Syphilis, secondary (45 y-o M)
    Multiple red-colored infiltrative papules on the neck and face of a lymphoma patient in a complete remission (biopsy from the neck skin)    
Key words : Treponema pallidum, secondary syphilis, condyloma latum
sexually transmitted infection
The papules are eroded, and biopsy was performed from one of the neck papules. Clinically, cutaneous recurrence of malignant lymphoma was suspected.   Dense infiltration of small lymphocytes and plasma cells is observed in the dermis. Hyperkeratotic acanthosis and exocytosis are associated (HE, low power).
In the dermis, infiltration of plasma cells is a prominent feature. Vascular endothelial cells are swollen. Pathologists should consider the possibility of syphilis under H&E observation.   Immunostaining using a commercially available antiserum to Treponema pallidum identifies numbers of coiled pathogens among the squamous epithelium. After the histopathological diagnosis, strongly positive Wassermann's reaction was serologically reconfirmed.
Reference case 166A
Palmar pastules as manifestation of secondary syphillis in a 30 y-o female (gross findings). The secondary syphilide is usually seen 6-8 weeks after the primary syphilitic lesion in the genitalia.
  Reference case 166B
Condyloma latum seen around the anus of a 33 y-o female (gross findings). Condyloma latum represents another example of the secondary syphilide.
Reference case 166B
Biopsy specimen shows irregular acanthosis and marked exocytosis with inflammatory edema in the dermis (HE). The histologic features are totally nonspecific. Without clinical information, it is difficult for pathologists to go to the next diagnostic step using histochemical approach.
  Reference case 166B
Immunostaining for Treponema pallidum antigen in the biopsy specimen of the anal skin. Numerous long spiral microbes are observed among the squamous epithelial cells, confirming the diagnosis of syphilis.