Small red dots on the glans and coronal sulcus are likely to be a sign of stage I syphilis hard chancre, but a laboratory test is needed to confirm the diagnosis. The hard chancre is a painless inflammatory reaction caused by the syphilis spirochete at the site of invasion. It occurs in the external genitalia, mostly in the penis, coronal sulcus, glans, prepuce and tether in men. The typical hard chancre starts as a small erythematous patch, which rapidly develops into a painless inflammatory papule, and within a few days the papule expands to form a hard nodule, and the surface becomes necrotic, forming a single 1-2 cm diameter round or oval painless ulcer with clear boundaries, edema and elevation around the periphery, a flesh-red base, cartilage-like hardness when touched, and a plasma discharge on the surface, containing a large number of syphilis spirochetes, which is highly contagious, often It is highly contagious and often solitary, sometimes 2-3 can be seen. It is often solitary and sometimes 2-3 chancre can be seen. Untreated chancre can last for 3-4 weeks and then subside on its own.