Boils

Definition

Boils and carbuncles are bacterial infections of hair follicles and surrounding skin that form pustules (small blister-like swellings containing pus) around the follicle. Boils are sometimes called furuncles. A carbuncle is formed when several furuncles merge to form a single deep abscess with several heads or drainage points.

Description

Boils and carbuncles are firm reddish swellings about 0.2-0.4in (5-10 mm) across that are slightly raised above the skin surface. They are sore to the touch. A boil usually has a visible central core of pus; a carbuncle is larger and has several visible heads. Boils occur most commonly on the face, back of the neck, buttocks, upper legs and groin area, armpits, and upper torso. Carbuncles are less common than single boils; they are most likely to form at the back of the neck. Males are more likely to develop carbuncles.

Boils and carbuncles are common problems in the general population, particularly among adolescents and adults. People who are more likely to develop these skin infections include those with:

• diabetes, especially when treated by injected insulin
• alcoholism or drug abuse
• poor personal hygiene
• crowded living arrangements
• jobs or hobbies that expose them to greasy or oily substances, especially petroleum products
• allergies or immune system disorders, including HIV infection.
• family members with recurrent skin infections

Causes and symptoms

Boils and carbuncles are caused by Staphylococcus aureus, a bacterium that causes an infection in an oil gland or hair follicle. Although the surface of human skin is usually resistant to bacterial infection, S. aureus can enter through a break in the skin surface—including breaks caused by needle punctures for insulin or drug injections. Hair follicles that are blocked by greasy creams, petroleum jelly, or similar products are more vulnerable to infection. Bacterial skin infections can be spread by shared cosmetics or washcloths, close human contact, or by contact with pus from a boil or carbuncle.

As the infection develops, an area of inflamed tissue gradually forms a pus-filled swelling or pimple that is painful to touch. As the boil matures, it forms a yellowish head or point. It may either continue to swell until the point bursts open and allows the pus to drain, or it may be gradually reabsorbed into the skin. It takes between one and two weeks for a boil to heal completely after it comes to a head and discharges pus. The bacteria that cause the boil can spread into other areas of the skin or even into the bloodstream if the skin around the boil is injured by squeezing. If the infection spreads, the patient will usually develop chills and fever, swollen lymph nodes (lymphadenitis ), and red lines in the skin running outward from the boil.

Furunculosis is a word that is sometimes used to refer to recurrent boils. Many patients have repeated episodes of furunculosis that are difficult to treat because their nasal passages carry colonies of S. aureus. These bacterial colonies make it easy for the patient's skin to be reinfected. They are most likely to develop in patients with diabetes, HIV infection, or other immune system disorders.

Carbuncles are formed when the bacteria infect several hair follicles that are close together. Carbunculosis is a word that is sometimes used to refer to the development of carbuncles. The abscesses spread until they merge with each other to form a single large area of infected skin with several pus-filled heads. Patients with carbuncles may also have a low-grade fever or feel generally unwell.

Diagnosis

The diagnosis of boils and carbuncles is usually made by the patient's primary care doctor on the basis of visual examination of the skin. In some cases involving recurrent boils on the face, the doctor may need to consider acne as a possible diagnosis, but for the most part boils and carbuncles are not difficult to distinguish from other skin disorders.

Treatment

Patient and family education

Patient education is an important part of the treatment of boils and carbuncles. Patients need to be warned against picking at or squeezing boils because of the danger of spreading the infection into other parts of the skin or bloodstream. It is especially important to avoid squeezing boils around the mouth or nose because infections in these areas can be carried to the brain. Patients should also be advised about keeping the skin clean, washing their hands carefully before and after touching the boil or carbuncle, avoiding the use of greasy cosmetics or creams, and keeping their towels and washcloths separate from those of other family members. Some doctors may recommend an antiseptic soap or gel for washing the infected areas.

If the patient has had several episodes of furunculosis, the doctor may examine family members or close contacts to see if they are carriers of S. aureus. In many cases they also need treatment for boils or carbuncles. Skin infections and reinfections involving small groups or clusters of people are being reported more frequently in the United States.

Medications

Boils are usually treated with application of antibiotic creams—usually clindamycin or polymyxin—following the application of hot compresses. The compresses help the infection to come to a head and drain.

Carbuncles and furunculosis are usually treated with oral antibiotics as well as antibiotic creams or ointments. The specific medications that are given are usually dicloxacillin (Dynapen) or cephalexin (Keflex). Erythromycin may be given to patients who are allergic to penicillin. The usual course of oral antibiotics is 5-10 days; however, patients with recurrent furunculosis may be given oral antibiotics for longer periods. Furunculosis is treated with a combination of dicloxacillin and rifampin (Rifadin).

Patients with bacterial colonies in their nasal passages are often given mupirocin (Bactroban) to apply directly to the lining of the nose.

Surgical treatment

Boils and carbuncles that are very large, or that are not draining, may be opened with a sterile needle or surgical knife to allow the pus to drain. The doctor will usually give the patient a local anesthetic if a knife is used; surgical treatment of boils is painful and usually leaves noticeable scars.

Alternative treatment

Naturopathic therapy

Naturopathic practitioners usually recommend changes in the patient's diet as well as applying herbal poultices to the infected area. The addition of zinc supplements and vitamin A to the diet is reported to be effective in treating boils. The application of a paste or poultice containing goldenseal (Hydrastis canadensis ) root is recommended by naturopaths on the grounds that goldenseal helps to kill bacteria and reduce inflammation.

KEY TERMS

Abscess— A localized collection of pus in the skin or other body tissue.

Carbuncle— A large, deep skin abscess formed by a group or cluster of boils.

Follicle— The small sac at the base of a hair shaft. The follicle lies below the skin surface.

Furunculosis— A condition in which the patient suffers from recurrent episodes of boils.

Pustule— A small raised pimple or blister-like swelling of the skin that contains pus.

Homeopathy

Homeopaths maintain that taking the proper homeopathic medication in the first stages of a boil or carbuncle will bring about early resolution of the infection and prevent pus formation. The most likely choices are Belladonna or Hepar sulphuris. If the boil has already formed, Mercurius vivus or Silica may be recommended to bring the pus to a head.

Western herbal therapies

A variety of herbal remedies can be applied topically to boils to fight infection. These include essential oils of bergamot (Citrus bergamia ), chamomile (Matricaria recutita ), lavender (Lavandula officinalis ), and sage (Salvia officinalis ), as well as tea tree oil (Melaleuca spp.). Herbalists also recommend washing the skin with a mixture of goldenseal and witch hazel. To fight the inflammation associated with boils, herbalists suggest marsh mallow (Althaea officinalis ) ointment, tinctures (herbal solutions made with alcohol) of blue flag (Iris versicolor ) or myrrh (Commiphora molmol ), and slippery elm (Ulmus fulva ) made into a poultice.

Prognosis

The prognosis for most boils is excellent. Some patients, however, suffer from recurrent carbuncles or furunculosis. In addition, although the spread of infection from boils is relatively unusual, there have been deaths reported from brain infections caused by squeezing boils on the upper lip or in the tissue folds at the base of the nose.

Prevention

There are some precautions that people can take to minimize the risk of developing bacterial skin infections:

• cleanse skin properly with soap and water, and take showers rather than tub baths
• do not share washcloths, towels, or facial cosmetics with others
• cut down on greasy or fatty foods and snacks
• always wash hands before touching the face
• consider using antiseptic soaps and shower gels
• consult a doctor if furunculosis is a persistent problem—it may indicate an underlying disease such as diabetes

Resources

BOOKS

Hacker, Steven M. "Common Bacterial and Fungal Infections of the Integument." In Current Diagnosis, edited by Rex B. Conn, et al. Vol 9. Philadelphia: W. B. Saunders Co., 1997.

Boils

Definition

Boils, also called furuncles, and carbuncles are bacterial infections of hair follicles and surrounding skin that form pustules (small blister-like swellings containing pus) around the follicle. A carbuncle results when several boils merge to form a single deep abscess with several heads, or drainage points.

Description

Boils and carbuncles are firm reddish swellings about 0.2-0.4 inches (5-10 mm) across that are slightly raised above the skin surface. They are sore to the touch. A boil usually has a visible central core of pus; a carbuncle is larger and has several visible heads. Boils occur most commonly on the face, back of the neck, buttocks, upper legs and groin area, armpits, and upper torso. Carbuncles are less common than single boils; they are most likely to form at the back of the neck. Males are more likely to develop carbuncles.

Boils and carbuncles are common problems in the general population, particularly among adolescents and adults. People who are more likely to develop these skin infections include those with:

• diabetes, especially when treated by injected insulin
• alcoholism or drug abuse
• poor personal hygiene
• crowded living arrangements
• jobs or hobbies that expose them to greasy or oily substances, especially petroleum products
• allergies or immune system disorders, including HIV infection
• family members with recurrent skin infections

Causes and symptoms

Boils and carbuncles usually are caused by Staphylococcus aureus, a bacterium that causes an infection in an oil gland or hair follicle, or they might be caused by other bacteria or fungi. Although the surface of human skin is usually resistant to bacterial infection, S. aureus can enter through a break in the skin surface—including breaks caused by needle punctures for insulin or drug injections. Hair follicles that are blocked by greasy creams, petroleum jelly, or similar products are more vulnerable to infection. Bacterial skin infections can be spread by shared cosmetics or washcloths, close human contact, or by contact with pus from a boil or carbuncle.

As the infection develops, an area of inflamed tissue gradually forms a pus-filled swelling or pimple that is painful to touch. As the boil matures, it forms a yellowish head or point. It may either continue to swell until the point bursts and allows the pus to drain, or it may gradually be reabsorbed into the skin. Boils can cause a lot of pain when they occur in the ear canal, nose, or other sensitive areas. It takes between one and two weeks for a boil to heal completely after it comes to a head, discharges pus, and crusts over. The bacteria that cause the boil can spread into other areas of the skin and even into the bloodstream if the skin around the boil is squeezed. If the infection spreads, the patient will usually develop chills and fever, swollen lymph nodes (lymphadenitis), and red lines in the skin running outward from the boil. Fatigue and general discomfort are other possible symptoms.

Furunculosis is sometimes used to refer to recurrent boils. Many patients have repeated episodes of furunculosis that are difficult to treat because their nasal passages carry colonies of S. aureus. These bacterial colonies make it easy for the patient's skin to be re-infected. They are most likely to develop in patients with diabetes, HIV infection, or other immune system disorders.

Carbuncles are formed when the bacteria infect several hair follicles that are close together. Carbunculosis is sometimes used to refer to the development of carbuncles. The abscesses spread until they merge with each other to form a single large area of infected skin with several pus-filled heads. Patients with carbuncles may also have a low-grade fever or feel generally unwell.

Diagnosis

The diagnosis of boils and carbuncles is usually made by the patient's primary care doctor on the basis of visual examination of the skin. In some cases involving recurrent boils on the face, the doctor may consider acne as a possible diagnosis, but, for the most part, boils and carbuncles are not difficult to distinguish from other skin disorders.

S. aureus can easily be cultured in the laboratory if the doctor needs to rule out inclusion cysts or deep fungal infections that gardeners sometimes get. The doctor can take a culture from pus taken from the boil or carbuncle to confirm the diagnosis of a staphylococcal infection. He or she can also culture the patient's nasal discharge to test for the presence of a S. aureus colony.

Treatment

Some boils heal spontaneously before progressing to pustules. Often, they become pustules that eventually burst, drain and then heal by themselves. Boils usually occur and are healed in about two weeks. Patients who have boils that take longer than two weeks to heal should see a doctor. Other reasons to seek professional medical advice are if boils recur, are located on the spine or the middle of the face, or are accompanied by symptoms such as fever. These boils are most at risk for spreading the infection.

Patient and family education

Patient education is an important part of the treatment of boils and carbuncles. Patients need to be warned against picking at or squeezing boils because of the danger of spreading the infection into other parts of the skin or bloodstream. It is especially important to avoid squeezing boils around the mouth or nose because infection in these areas can be carried to the brain. Patients should also be advised about keeping the skin clean, washing their hands carefully before and after touching the boil or carbuncle, avoiding the use of greasy cosmetics or creams, and keeping their towels and washcloths separate from those of other family members. Some doctors may recommend an antiseptic soap or gel for washing the infected areas. People who have boils often benefit from applying warm compresses several times a day to help the boils come to a head and drain.

If the patient has had several episodes of furunculosis, the doctor may examine family members or close contacts to see if they are carriers of S. aureus. In many cases, some of the family members may also need treatment for boils or carbuncles. Skin infection and reinfection involving small groups or clusters of people are being reported more frequently in the United States.

Medications

Boils are usually treated with application of topical antibiotic creams, such as clindamycin or polymyxin, following the use of hot compresses to help the infection drain, which speeds healing.

Carbuncles and furunculosis are usually treated with oral antibiotics as well as topical antibiotic creams or ointments. The specific medications that are given are usually dicloxacillin (Dynapen) or cephalexin (Keflex); erythromycin may be given to patients who are allergic to penicillin. The usual course of oral antibiotics is 5-10 days, although patients with recurrent furunculosis may be prescribed oral antibiotics for longer periods. Furunculosis is also treated with a combination of dicloxacillin and rifampin (Rifadin). Still, many experts agree that topical antibiotics help very little once the boil has formed.

Patients with bacterial colonies in their nasal passages are often given mupirocin (Bactroban) to apply directly to the lining of the nose.

Surgical treatment

Boils and carbuncles that are very large, or that are not draining, may be opened by a doctor with a sterile needle or surgical knife to allow the pus to drain. The patient is usually administered a local anesthetic if a knife is used as surgical treatment of boils is painful, and frequently leaves noticeable scars.

Alternative treatment

Naturopathic practitioners usually recommend changes in the patient's diet as well as applying herbal poultices to the infected area. The addition of zinc supplements and vitamin A to the diet has been reported to be effective in treating boils. The application of a paste or poultice containing goldenseal root (Hydrastis canadensis) is recommended by naturopaths on the grounds that goldenseal helps to kill bacteria and reduce inflammation.

Homeopaths maintain that taking the proper homeopathic medication in the first stages of a boil or carbuncle will bring about early resolution of the infection and prevent pus formation. The most likely choices are Belladonna or Hepar sulphureus. If the boil has already formed, Mercurius vivus or Silica may be recommended to bring the pus to a head.

A variety of herbal remedies can be applied topically to boils to fight infection. These include essential oils of bergamot (Citrus bergamia), chamomile (Matricaria recutita), lavender (Lavandula officinalis), and sage (Salvia officinalis), as well as tea tree oil (Melaleuca spp.). Herbalists also recommend washing the skin with a mixture of goldenseal and witch hazel. To fight the inflammation associated with boils, herbalists suggest mixing marsh mallow (Althaea officinalis) ointment, tinctures (herbal solutions made with alcohol) of blue flag (Iris versicolor) or myrrh (Commiphora mol mol), and slippery elm (Ulmus fulva) into a poultice.

Prognosis

The prognosis for most boils is excellent, although some patients suffer from recurrent carbuncles or furunculosis. In addition, though the spread of infection from boils is relatively unusual, there have been deaths reported from brain infections caused by squeezing boils on the upper lip or in the tissue folds at the base of the nose. Some patients also experience permanent scarring of the skin.

Health care team roles

Nurses help to educate patients about how to avoid infection of boils, ensure proper healing, and prevent recurrence. The nurse might also take a culture of the affected area to confirm the doctor or nurse practitioner's diagnosis. If in-office surgery to drain the boil is indicated, the nurse might assist in preparation for the procedure and during the procedure.

KEY TERMS

Abscess— A localized collection of pus in the skin or other body tissue.

Carbuncle— A large, deep skin abscess formed by a group or cluster of boils.

Follicle— The small sac at the base of a hair shaft. The follicle lies below the skin surface.

Furunculosis— A condition in which the patient suffers from recurrent episodes of boils.

Pustule— A small raised pimple or blister-like swelling of the skin that contains pus.

Prevention

There are some precautions that people can take to minimize the risk of developing bacterial skin infections:

• Cleanse the skin properly with soap and water, and take showers rather than tub baths.
• Do not share washcloths, towels, or facial cosmetics with others.
• Cut down on greasy or fatty foods.
• Always wash hands before touching the face.
• Consider using antiseptic soaps and shower gels.

• Consult a doctor if furunculosis is a persistent problem—it may indicate an underlying disease such as diabetes.

Resources

BOOKS

Berger, Timothy G. "Skin and Appendages." In Current Medical Diagnosis and Treatment 1998, edited by Lawrence M. Tierney, Jr. et al. Stamford, CT: Appleton and Lange, 1997.

Hacker, Steven M. "Common Bacterial and Fungal Infections of the Integument." In Current Diagnosis 9, edited by Rex B. Conn et al. Philadelphia: W.B. Saunders, 1997.

Rasmussen, James E. "Bacterial Infections of the Skin." In Conn's Current Therapy, edited by Robert E. Rakel. Philadelphia: W.B. Saunders, 1998.

OTHER

"Furuncle." WebMD. 1999. 〈http://my.webmd.com/content/asset/adam_disease_boils〉.

Boils

Definition

Boils are bacterial infections of hair follicles and the surrounding skin that form pustules around the follicle. Boils are sometimes called furuncles. When several furuncles merge to form a single deep sore with several "heads," or drainage points, the result is called a carbuncle.

Description

Boils are firm, red swellings about 5–10 mm across that are slightly raised above the skin surface. They are sore to the touch. A boil usually has a visible central core of pus; a carbuncle is larger and has several visible heads. Boils occur most commonly on the face, back of the neck, buttocks, upper legs and groin area, armpits, and upper torso. Carbuncles are less common than single boils; they are most likely to form at the back of the neck. Men are more likely than women to develop carbuncles.

As the infection that causes the boil develops, an area of inflamed tissue gradually forms a pus-filled swelling or pimple that is painful to touch. As the boil matures, it forms a yellowish head or point. It may either continue to swell until the point bursts open and allows the pus to drain, or it may be gradually reabsorbed into the skin. It generally takes between one and two weeks for a boil to heal completely after it comes to a head and

discharges pus. The bacteria that cause the boil can spread into other areas of the skin or even into the bloodstream if the skin around the boil is squeezed. If the infection spreads, the patient will usually develop chills, fever , and swollen lymph nodes. Red lines may appear on the skin running outward from the boil.

Boils and carbuncles are common problems in the general population, particularly among adolescents and adults. People who are most likely to develop these skin infections include those with:

• diabetes, especially when treated by injected insulin
• alcoholism or drug abuse
• recent experience of childbirth , especially women who are breastfeeding their babies
• poor personal hygiene
• crowded living arrangements
• jobs or hobbies that expose them to greasy or oily substances, especially petroleum products
• hair styles requiring frequent use of hair relaxers
• allergies or immune system disorders, including HIV infection

Causes & symptoms

Boils are most often caused by Staphylococcus aureus (staph), a bacterium that causes an infection in an oil gland or hair follicle. Although the surface of human skin is usually resistant to bacterial infection, staph can enter through a break in the skin surface, including breaks caused by needle punctures for insulin or drug injections. Hair follicles that are blocked by greasy creams, petroleum jelly, hair relaxers, or similar products are more vulnerable to developing boils. These bacterial skin infections can be spread by shared cosmetics or washcloths, close human contact, or by contact with pus from another boil or carbuncle.

Carbuncles are formed when the bacteria infect several hair follicles that are close together. Carbunculosis is a word that is sometimes used to refer to the development of carbuncles. The abscesses spread until they merge with each other to form a single large area of infected skin with several pus-filled heads. Patients with carbuncles may also have a low-grade fever or feel generally unwell.

Furunculosis is a word used to refer to recurrent boils. Many patients have repeated episodes of furunculosis that are difficult to treat because their nasal passages carry colonies of staph. Skin and anal colonization are fairly common as well. Persistent furunculosis may be an indication of a depressed immune system. A physician should be consulted if boils are a persistent problem in order to determine whether there is an underlying disease such as diabetes, HIV infection, or immune system disorders.

Diagnosis

A diagnosis of boils is usually made on the basis of visual examination of the skin. For the most part, boils are not difficult to distinguish. A doctor can make a culture from pus taken from the boil to confirm the diagnosis and treatment. The patient's nasal discharge may also be tested. In cases of persistent recurrent boils, family members or close contacts may be examined to see if they are carriers of staph.

Treatment

Patient education is an important part of the treatment of boils. Patients need to be warned against squeezing boils because of the danger of spreading the infection into other parts of the skin or bloodstream. It is especially important to avoid squeezing boils around the mouth or nose, because infections in these areas may be carried to the brain, although this happens rarely. Patients should also be advised about keeping the skin clean, washing their hands carefully before and after touching the boil, avoiding the use of greasy cosmetics or creams, and keeping their towels and washcloths separate from those of other family members.

The use of the following supplements is reported to be effective in treating boils: zinc , 45 mg per day; vitamin A , 50,000 IUs per day for two weeks; vitamin C ,1 g three times per day; and beta-carotene, 100,000 IUs per day.

Taking the proper homeopathic medication in the first stages of a boil can bring about early resolution of the infection and prevent pus formation. The most likely choices are belladonna or Hepar sulphuris. If the boil has already formed, Mercurius vivus or silica may be recommended to bring the pus to a head.

A variety of herbal remedies can be applied topically to fight infection. These include essential oils of bergamot, Citrus bergamia; chamomile , Matricaria recutita; lavender , Lavandula officinalis; and sage , Salvia officinalis; as well as tea tree oil , Melaleuca spp. Application of a paste or poultice containing goldenseal root, Hydrastis canadensis, is recommended to help kill bacteria and to reduce inflammation. Washing the skin around the affected area with a mixture of goldenseal, Hydrastis canadensis, and witch hazel , Hamamelis virginiana, dissolved in warm water is also recommended.

Allopathic treatment

Boils are usually treated with application of antibiotic creams, following the application of hot compresses. The compresses help the infection to come to a head and drain and are an important part of the treatment regime. Carbuncles and furunculosis are usually treated with oral antibiotics as well as antibiotic creams or ointments. The usual course of oral antibiotics is 5-10 days; however, patients with recurrent furunculosis may be given oral antibiotics for longer periods. Patients with bacterial colonies in their nasal passages are often given mupirocin ointment (Bactroban) to apply directly to the lining of the nose and should wash the area once a month with an antiseptic soap such as Phisohex.

Boils or carbuncles that are very large or that do not resolve may be opened with a sterile needle or surgical knife to allow the pus to drain. Surgical treatment of boils is often painful and usually leaves noticeable scars.

The increase of antibiotic- and biocide-resistant strains of Staphylococcus aureus has caused growing concern among doctors, as some of these strains are now resistant to disinfectants used to clean endoscopes and other surgical equipment. Resveratrol, which is a phytoalexin, or compound formed by plants at the site of a fungal or bacterial invasion, appears to be highly effective in treating boils and other skin infections in humans caused by S. aureus.

Expected results

Boils usually drain or are reabsorbed in two or three days. Recurrent boils and carbuncles, however, are fairly common. In addition, although the spread of infection from boils is relatively unusual, there have been deaths reported from brain infections caused by squeezing boils on the upper lip or in the tissue folds at the base of the nose.

Prevention

To minimize the risk of developing bacterial skin infections the skin should be kept clean; to avoid spreading the infection, washcloths, towels, and facial cosmetics should not be shared with others. A healthy diet should be maintained and allergic foods should be eliminated. This will ensure that the immune system will be supported, and that boils will be prevented.

Resources

BOOKS

Conn, Rex B., ed., et. al. Current Diagnosis 9. Philadelphia: W.B. Saunders, 1997.

Rakel, Robert E., ed. Conn's Current Therapy. Philadelphia: W.B. Saunders, 1998.

Tierney, Jr., Lawrence, ed., et. al. Current Medical Diagnosis & Treatment, 1998. Connecticut: Appleton & Lange, 1997.

Turkington, Carol A., and Jeffrey S. Dover. Skin Deep: An A-Z of Skin Disorders, Treatments, and Health. New York: Facts On File, 1996.

PERIODICALS

Amir, L. "Breastfeeding and Staphylococcus aureus : Three Case Reports." Breastfeeding Review 10 (March 2002): 15-18.

Chan, M. M. "Antimicrobial Effect of Resveratrol on Dermatophytes and Bacterial Pathogens of the Skin." Biochemical Pharmacology 63 (January 15, 2002): 99-104.

Fraise, A. P. "Susceptibility of Antibiotic-Resistant Cocci to Biocides." Journal of Applied Microbiology 92 (2002 Supplement): 158S-162S.

Kaur, B. J., H. Singh, and A. Lin-Greenberg. "Irritant Contact Dermatitis Complicated by Deep-Seated Staphylococcal Infection Caused by a Hair Relaxer." Journal of the National Medical Association 94 (February 2002): 121-123.

Oliveira, D. C., A. Tomasz, and H. de Lencastre. "Secrets of Success of a Human Pathogen: Molecular Evolution of Pandemic Clones of Methicillin-Resistant Staphylococcus aureus." Lancet Infectious Diseases 2 (March 2002): 180-189.

Patience Paradox

Rebecca J. Frey, PhD

Boils

Definition

Boils and carbuncles are bacterial infections of hair follicles and surrounding skin that form pustules (small blister-like swellings containing pus) around the follicle. Boils are sometimes called furuncles. A carbuncle is formed when several furuncles merge to form a single deep abscess with several heads or drainage points.

Description

Boils and carbuncles are firm reddish swellings about 0.2–0.4 in (5–10 mm) across that are slightly raised above the skin surface. They are sore to the touch. A boil usually has a visible central core of pus; a carbuncle is larger and has several visible heads. Boils occur most commonly on the face, back of the neck, buttocks, upper legs and groin area, armpits, and upper torso. Carbuncles are clusters of boils that usually form on the back of the neck. Older men develop carbuncles in the thighs or shoulders in addition to the back of the neck. Carbuncles form at a slower rate than single boils. They require more time to heal and often leave a scar.

Boils and carbuncles are common problems in the general population, particularly among adolescents and adults. People who are more likely to develop these skin infections include those with:

• diabetes, especially when treated by injected insulin
• alcoholism or drug abuse
• kidney failure
• poor personal hygiene
• crowded living arrangements
• jobs or hobbies that expose them to greasy or oily substances, especially petroleum products
• allergies or immune system disorders, including HIV infection
• rheumatoid arthritis
• cancer
• family members with recurrent skin infections

Certain medications that affect the immune system also increase the possibility of developing boils. These medicines include cortisone drugs such as prednisone and medicines used for cancer chemotherapy .

Causes and symptoms

Boils and carbuncles are caused by Staphylococcus aureus, a bacterium that causes an infection in an oil gland or hair follicle. Although the surface of human skin is usually resistant to bacterial infection, S. aureus can enter through a break in the skin surface-including breaks caused by needle punctures for insulin or drug injections. Hair follicles that are blocked by greasy creams, petroleum jelly, or similar products are more vulnerable to infection. Bacterial skin infections can be spread by shared cosmetics or washcloths, close human contact, or by contact with pus from a boil or carbuncle. Certain conditions that result in boils include Cystic acne that usually occurs on the face and is the result of blocked and infected skin pores, Hidradenitis suppurativa, or inflammation of the sweat glands whereby multiple boils form under the armpits and also in the groin area and Pilonidal cysts—boils that form in the crease of the buttocks as a result of hair follicle infection.

As the infection develops, an area of inflamed tissue gradually forms a pus-filled swelling or pimple that is painful to touch. As the boil matures, it forms a yellowish head or point. It may either continue to swell until the point bursts open and allows the pus to drain, or it may be gradually reabsorbed into the skin. It takes between one and two weeks for a boil to heal completely after it comes to a head and discharges pus. The bacteria that cause the boil can spread into other areas of the skin or even into the bloodstream if the skin around the boil is injured by squeezing. If the infection spreads, the patient will usually develop chills and fever, swollen lymph nodes (lymphadenitis), and red lines in the skin running outward from the boil.

Furunculosis is a word that is sometimes used to refer to recurrent boils. Many patients have repeated episodes of furunculosis that are difficult to treat because their nasal passages carry colonies of S. aureus. These bacterial colonies make it easy for the patient's skin to be reinfected. They are most likely to develop in patients with diabetes, HIV infection, or other immune system disorders.

Carbuncles are formed when the bacteria infect several hair follicles that are close together. Carbunculosis is a word that is sometimes used to refer to the development of carbuncles. The abscesses spread until they merge with each other to form a single large area of infected skin with several pus-filled heads. Patients with carbuncles may also have a low-grade fever or feel generally unwell.

KEY TERMS

Abscess —A localized collection of pus in the skin or other body tissue.

Carbuncle —A large, deep skin abscess formed by a group or cluster of boils.

Follicle —The small sac at the base of a hair shaft. The follicle lies below the skin surface.

Furunculosis —A condition in which the patient suffers from recurrent episodes of boils.

Pustule —A small raised pimple or blister-like swelling of the skin that contains pus.

Diagnosis

The diagnosis of boils and carbuncles is usually made by the patient's primary care doctor on the basis of visual examination of the skin. In some cases involving recurrent boils on the face, the doctor may need to consider acne as a possible diagnosis, but for the most part boils and carbuncles are not difficult to distinguish from other skin disorders.

Treatment

Medications

Boils are usually treated with application of antibiotic creams—usually clindamycin or polymyxin-following the application of hot compresses. The compresses help the infection to come to a head and drain.

Carbuncles and furunculosis are usually treated with oral antibiotics as well as antibiotic creams or ointments. The specific medications that are given are usually dicloxacillin (Dynapen) or cephalexin (Keflex). Erythromycin may be given to patients who are allergic to penicillin. The usual course of oral antibiotics is 5-10 days; however, patients with recurrent furunculosis may be given oral antibiotics for longer periods. Furunculosis is treated with a combination of dicloxacillin and rifampin (Rifadin).

Patients with bacterial colonies in their nasal passages are often given mupirocin (Bactroban) to apply directly to the lining of the nose.

Surgical treatment

Boils and carbuncles that are very large, or that are not draining, may be opened with a sterile needle or surgical knife to allow the pus to drain. The doctor will usually give the patient a local anesthetic if a knife is used; surgical treatment of boils is painful and usually leaves noticeable scars.

Alternative treatment

Naturopathic practitioners usually recommend changes in the patient's diet as well as applying herbal poultices to the infected area. The addition of zinc supplements and vitamin A to the diet is reported to be effective in treating boils. The application of a paste or poultice containing goldenseal (Hydrastis canadensis) root is recommended by naturopaths on the grounds that goldenseal helps to kill bacteria and reduce inflammation.

Homeopaths maintain that taking the proper homeopathic medication in the first stages of a boil or carbuncle will bring about early resolution of the infection and prevent pus formation. The most likely choices are Belladonna or Hepar sulphuris. If the boil has already formed, Mercurius vivus or Silica may be recommended to bring the pus to a head.

A variety of herbal remedies can be applied topically to boils to fight infection. These include essential oils of bergamot (Citrus bergamia), chamomile (Matricaria recutita), lavender (Lavandula officinalis), and sage (Salvia officinalis), as well as tea tree oil (Melaleuca spp.). Herbalists also recommend washing the skin with a mixture of goldenseal and witch hazel. To fight the inflammation associated with boils, herbalists suggest marsh mallow (Althaea officinalis) ointment, tinctures (herbal solutions made with alcohol) of blue flag (Iris versicolor) or myrrh (Commiphora molmol), and slippery elm (Ulmus fulva) made into a poultice.

Prognosis

The prognosis for most boils is excellent. Some patients, however, suffer from recurrent carbuncles or furunculosis. In addition, although the spread of infection from boils is relatively unusual, there have been deaths reported from brain infections caused by squeezing boils on the upper lip or in the tissue folds at the base of the nose.

Prevention

There are some precautions that people can take to minimize the risk of developing bacterial skin infections:

• cleanse skin properly with soap and water, and take showers rather than tub baths. Consider using a loofah-style brush in the shower to help prevent blockage in oil glands and hair follicles.
• do not share washcloths, towels, or facial cosmetics with others
• cut down on greasy or fatty foods and snacks
• always wash hands before touching the face
• consider using antiseptic soaps and shower gels. Certain cleansers including pHisoderm help eliminate the amount of bacteria on the skin.
• consult a doctor if furunculosis is a persistent problem—it may indicate an underlying disease such as diabetes

Caregiver concerns

Patient education is an important part of the treatment of boils and carbuncles. Patients need to be warned against picking at or squeezing boils because of the danger of spreading the infection into other parts of the skin or bloodstream. It is especially important to avoid squeezing boils around the mouth or nose because infections in these areas can be carried to the brain. Patients should also be advised about keeping the skin clean, washing their hands carefully before and after touching the boil or carbuncle, avoiding the use of greasy cosmetics or creams, and keeping their towels and washcloths separate from those of other family members. Some doctors may recommend an antiseptic soap or gel for washing the infected areas.

If the patient has had several episodes of furunculosis, the doctor may examine family members or close contacts to see if they are carriers of S. aureus. In many cases they also need treatment for boils or carbuncles. Skin infections and reinfections involving small groups or clusters of people are being reported more frequently in the United States.

Resources

PERIODICALS

Anderson, Deverick J. M.D. and Keith S. Kaye MD, MPH. “Skin and Soft Tissue Infections in Older Adults.” Clinics in Geriatric Medicine 23, no.3(August, 2007): 595–613.

OTHER

Medline Plus. March 10, 2008. http://www.mayoclinic.com/.

Mayo Clinic. March 25, 2008. http://www.http://medlineplus.gov/.

Rebecca J. Frey Ph.D.

Lisa M. Piazza M.A.