What are the signs of stage 1 syphilis (hard chancre)? The main manifestation of stage 1 syphilis is hard chancre, which mostly occurs in the genital area. The hard chancre appears 2 to 4 weeks after sexual intercourse and starts as a papule or rice-grain sized erythema, which later rises and forms a hard nodule as large as a pea or a finger, mostly solitary, and soon breaks down and erupts. The characteristics of hard chancre are (1) cartilage-like hardness on palpation; (2) no pain and pressure (when there is no secondary infection); (3) without treatment, it disappears naturally in about 3-6 weeks, leaving no trace or a mild atrophic scar. Therefore, stage I syphilis is easily ignored by patients. A few days after the appearance of hard chancre, one inguinal lymph node swells and later the other side also swells. What are the signs of stage II syphilis? Stage II syphilis skin rash is characterized by widespread and symmetrical distribution, no discomfort, less destructive and highly contagious. If round red spots appear on the palms of the hands and feet, without itching or pain, this is the most characteristic manifestation of the second-stage syphilis rash. Common second-stage syphilis rash has the following forms: ① rash. There may be maculopapular rash (rose rash), maculopapular rash, papular rash, papular scaly syphilis rash, follicular rash, pustular rash, oyster shell rash and ulcerative rash; ② flat warts; ③ syphilitic alopecia; ④ mucosal damage. Stage II syphilis rash has a wide variety of manifestations and can be similar to the rashes of many skin diseases, which can be easily misdiagnosed. Will the second syphilis rash go away naturally without treatment? The first occurrence of the second syphilis rash is called early syphilis rash, without treatment in 1 to 3 months can naturally fade, generally does not leave traces, but does not indicate that the syphilis automatically eliminated, but into the incubation period, at a certain time will recur, called recurrent syphilis rash. This rash is small in number and more limited in distribution, and is still infectious. It is more likely to recur within the first 1-2 years and can be repeated several times. Some patients have a strong body resistance and the rash is mild and can be easily overlooked. What is stage III syphilis? Stage III syphilis, also known as late syphilis, occurs 2 to 4 years after infection. It is mostly damage to the skin, mucous membranes and bones, and can invade important organs such as the cardiovascular and nervous systems after 10 to 20 years. Stage III syphilis is characterized by very little infectiousness, but it is very destructive to tissues and can be life-threatening in severe cases. If left untreated, the course of stage III syphilis is slow and can take as long as 10 to 30 years. Does untreated syphilis always lead to stage III syphilis? Not necessarily. The occurrence of stage III syphilis varies from person to person. Only 30% to 40% of patients with untreated early syphilis (including stage I and II syphilis) will develop stage III syphilis. What are the three main types of rashes in stage III syphilis? The three main types of rashes are nodular syphilis rash, arthrogryposis and proximal joint nodules.