What Causes Boils?:

A boil is an infection of a follicle (hair cell) which causes painful swelling, inflammation and an accumulation of fluid under the skin. The medical name for this condition is folliculitis. When several boils occur in a cluster, it is called a carbuncle. In the Western world, the most common cause is staphylococcal bacteria, which travels down the hair to its root. In some cases, the bacteria can also enter the body through tiny cracks or scratches in the skin. Boils can also occur when foreign matter such as a splinter becomes lodged under the skin. In cases of acne, boils are formed by infected sweat glands. In parts of Africa, boils may be caused by myiasis carried by insects.

A boil consists of a red, swollen area surrounding a pocket of white blood cells mixed with bacteria and proteins, a mixture commonly called pus. Pressure builds up as the boil grows, becoming very painful. In most cases, the boil will open and discharge the pus spontaneously. In severe cases, it may be necessary to lance the boil. Boils occur most commonly on the buttocks, face, neck, armpits and shoulders. When one appears on an eyelid, it is called a sty.

Boils can result from poor nutrition and bad hygiene as well as certain health conditions such as diabetes and obesity. The condition is sometimes caused by exposure to irritating chemicals. Persons whose immune systems have become compromised are at high risk, and the condition is sometimes seen in patients who are on immunosuppressant drugs. Cortisone medications such as prednisone and prednisolone are commonly used medications that can cause this effect. Diseases that disrupt the operation of the immune system, such as hypogammaglobulinemia, are often accompanied by boils. The condition sometimes occurs in cancer patients who are on chemotherapy. Cases of kidney failure are often accompanied by boils.

If a boil occurs in an area where continuous pressure may be applied to it, this can greatly increase the severity of the infection. If possible, one should note an infected hair as soon as it begins to develop and avoid placing pressure on it. If the pus does not discharge soon after forming a head, lancing should be performed. Failure to take these precautions may cause the condition to be more severe than necessary.

In extreme cases, boils can cause sepsis posing a serious threat to health, producing symptoms of fever and lethargy. Fatalities are rare but not unknown. Permanent scarring may occur. Boils may appear internally and cause damage to organs such as the brain, spinal cord and kidneys. Severe boils pose a particular risk to persons with heart murmurs, since these patients have an elevated risk of sepsis.