Staphylococcus (staph) bacteria are a germ found on a person’s skin, and they typically cause no problems. But a staph infection can develop, resulting in a boil—a pus-filled, painful bump. They might look like cystic acne lumps, but tend to be more inflamed, reddened and more uncomfortable. In some cases, this bacteria can enter your bloodstream and infect your whole body with an infection called sepsis, which is life-threatening. That's why it's important to identify staph boils early and get them treated.
Look for staph boils around the buttocks, groin or under your arms because these are the most common locations. They can also occur in hairy areas, where you might sweat or have friction.
Know the difference between a staph boil and other staph infections. For example, impetigo also is caused by staph bacteria, but it looks like a rash of large blisters around the mouth and nose. Another type is cellulitis, which looks like an orange peel and occurs on the feet and legs. One last skin-related staph infection is scalded skin syndrome, which is a rash that looks like a raw, red burn.
Correctly identify a staph boil because it looks like a pocket of pus that's red or pink and swollen. It usually occurs in an oil gland or hair follicle. It can be 1/2 inch to 3/4 inch in diameter, although the skin around it may also be inflamed or swollen. If it bursts, it may ooze blood, pus or an amber liquid.
Follow the progress of the bump. If it's a boil, it fills with pus within a few days and grows larger, sometimes as big as a golf ball. A white or yellow tip may develop that can burst and drain.
Know the potential outcome. Staph boils often clear up in a few weeks and heal without scarring if they are small. But if they don't heal within that time, they can become deeper, spread and potentially infect your bloodstream.
See a doctor if the staph boil quickly worsens or is very painful, doesn't heal in two weeks, you have a fever, you get boils often or there are red lines extending from the staph boil (which means an infection is spreading). You should also call you doctor if you have HIV or any other condition in which your immune system is suppressed.