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What is A 23-year-old presented with painless penile ulcer and painless lymphadenopathy. What is the diagnosis and explain in detail?
In syphilis, the primary lesion is the chancre at the site of entry of the spirochete. In all but a few, the chancre is genital. Other common sites are the mouth and nipples. The chancre is painless, relatively avascular, circumscribed, indurated, superficially ulcerated lesion. It is known as 'hard chancre' to distinguish it from the non-indurated lesions of 'soft chancre' caused by H.dureyi. Ref: Textbook of microbiology; Ananthanarayan and paniker's; 10th edition; Pg:379