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Published on: February 8, 2019
Histologic Features of Secondary Syphilis
1Department of Dermatology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Background:
Secondary syphilis is a sexually transmitted infection, which is referred to as "the great imitator" and has a wide spectrum of clinical manifestations. As a result, it is essential to identify potential secondary syphilis patients with ambiguous clinical manifestation through pathology.
Objective:
We sought to analyze the pathological features of secondary syphilis.
Methods:
We analyzed 59 biopsy specimens from 56 patients with secondary syphilis. Cases were classified according to the histological characteristics and clinical features.
Results:
Necrotic keratinocytes could be observed in 39 of 59 (66.1%) secondary specimens. Plasma cells (86.4%) were the most common finding overall. The presence of Treponema pallidum was detected mostly at the dermal-epidermal junction. There was no statistical significance between pathological features and age, HIV status, or RPR titer.
Conclusions:
Necrotic keratinocytes are one of the characteristics of secondary syphilis. The combination of plasma cells, irregular acanthosis, elongated rete ridges, and endothelial swelling should increase the likelihood of syphilis.
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