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"How bad does an infection have to be before I see a doctor about it?"


About a week ago, a small red bump appeared about three inches above my right kneecap. Over the course of three days, the skin reddened in a radius of 4", became swollen, the skin turned shiny, and red streaking appeared. I'm really trying to avoid making a doctor's appointment, but I would like to know how serious this has to get before I should schedule an appointment to combat it with antibiotics.


This sounds like possibly a very serious skin infection and you should see your doctor immediately without delay. When bacteria get into the skin through small breaks or nicks in the skin, they can cause an infection. Initially this may be a small pimple or blister, but if the infection begins to spread, this is called cellulitis.

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Cellulitis is characterized by redness, swelling, pain, and warmth of the skin, often with streaks of redness, which is the inflammation moving up the lymphatic ducts draining fluids from the area of the infection. Cellulitis can spread quickly and can be very serious, especially if the infection passes into the bloodstream. Cellulitis is treated with antibiotics and, depending upon how large the area of infection is and what other medical problems you have (such as diabetes), this can sometimes require hospitalization for intravenous antibiotics. It is absolutely critical that you not wait any longer to see your doctor. If you cannot get into to see your doctor promptly, or if there are any serious symptoms such as high fever and chills, blisters, or rapidly spreading redness, you should not wait to see your doctor but should instead go to the emergency room.

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