Question
Suddenly discovered a red circle on my foot, painless and itchy, but painful only when pressed. What could this be? Is it serious?
Answer
This condition may be related to syphilis, particularly the characteristic clinical feature of primary syphilis—chancre. Approximately 7 to 60 days after infection, patients may develop solitary, painless, and itchy circular or oval ulcers with clear borders. The surface is relatively clean, and there may be more discharge if secondary infection occurs. The ulcers have a soft bony hardness when touched and typically last for about 4 to 6 weeks, healing spontaneously. It is advisable to seek medical attention for a detailed examination to determine the cause and receive appropriate treatment.