Folliculitis  Information for adults

Folliculitis occurs in people of all ethnicities, all ages, and both sexes.

Other risk factors for folliculitis include:

• Diabetes
• Suppressed immune system due to HIV, organ transplantation, or cancer
• An underlying skin condition, such as eczema, acne, or another dermatitis
• Obesity
• Frequent shaving
• Pressure (prolonged sitting on the buttocks)

The most common locations for folliculitis include:

• Scalp
• Beard area in men
• Underarms, groin, or legs in women
• Buttocks
• Thighs

Individual lesions of folliculitis include pus-filled bumps (pustules) centered on hair follicles. These pus-filled bumps may be pierced by an ingrown hair, can vary in size from 2–5 mm, and are often surrounded by a rim of pink to red, inflamed skin. Occasionally, a folliculitis lesion can erupt to form a scab on the surface of the skin.

Mild and moderate cases of folliculitis are often tender or itchy. More severe cases of folliculitis, which may be deeper and may affect the entire hair follicle, may be painful.

Mild and moderate cases of folliculitis usually clear quickly with treatment and leave no scars. However, more severe cases of folliculitis may lead to complications, such as cellulitis (an infection of the deeper skin tissue), scarring, or permanent hair loss.

In order to prevent folliculitis, try the following:

• Shave in the same direction of hair growth.
• Avoid shaving irritated skin.
• Use an electric razor or a new disposable razor each time you shave.
• Consider other methods of hair removal, such as depilatories.
• Avoid tight, constrictive clothing, especially during exercise.
• Wash athletic wear after each use.

The following measures may help to clear up folliculitis if it is mild:

• Use an antibacterial soap.
• Apply hot, moist compresses to the involved area.
• Launder towels, washcloths, and bed linens frequently, and do not share such items with others.
• Wear loose-fitting clothing.

Make an appointment to be evaluated by a dermatologist or by another physician if the above self-care measures do not resolve the condition within 2–3 days, if symptoms recur frequently, or if the infection spreads.

Be sure to tell your doctor about any recent exposure to hot tubs, spas, or swimming pools, as a less common form of folliculitis may be caused by contamination from these water sources.

If you are currently being treated for a skin infection that has not improved after 2–3 days of antibiotics, return to your doctor.

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is a strain of "staph" bacteria resistant to antibiotics in the penicillin family, which have been the cornerstone of antibiotic therapy for staph and skin infections for decades. CA-MRSA previously infected only small segments of the population, such as health care workers and persons using injection drugs. However, CA-MRSA is now becoming a more common cause of skin infections in the general population. While CA-MRSA bacteria are resistant to penicillin and penicillin-related antibiotics, most staph infections with CA-MRSA can be easily treated by health care practitioners using local skin care and commonly available non-penicillin-family antibiotics. Rarely, CA-MRSA can cause serious skin and soft tissue (deeper) infections. Staph infections typically start as small red bumps or pus-filled bumps, which can rapidly turn into deep, painful sores. If you see a red bump or pus-filled bump on the skin that is worsening or showing any signs of infection (ie, the area becomes increasingly painful, red, or swollen), see your doctor right away. Many people believe incorrectly that these bumps are the result of a spider bite when they arrive at the doctor's office. Your doctor may need to test (culture) infected skin for MRSA before starting antibiotics. If you have a skin problem that resembles a CA-MRSA infection or a culture that is positive for MRSA, your doctor may need to provide local skin care and prescribe oral antibiotics. To prevent spread of infection to others, infected wounds, hands, and other exposed body areas should be kept clean and wounds should be covered during therapy.

Folliculitis is fairly easy to diagnose in most cases. Your physician may wish to perform a bacterial culture in order to determine the cause of the folliculitis. The procedure involves:

1. Penetrating the pus-filled lesion with a needle, scalpel, or lancet.
2. Rubbing a sterile cotton-tipped applicator across the skin to collect the pus.
3. Sending the specimen away to a laboratory.

Typically, the laboratory will have preliminary results within 48–72 hours if there are many bacteria present. However, the culture may take a full week or more to produce final results. In addition to identifying the strain of bacteria that is causing the folliculitis, the laboratory usually performs antibiotic sensitivity testing in order to determine the medications that will be most effective in killing off the bacteria.

Depending on bacterial culture results, your physician may recommend the following treatments:

• Prescription-strength antibacterial wash, such as chlorhexidine gluconate
• Topical antibiotic lotion or gel, such as erythromycin or clindamycin
• Oral antibiotic pills, such as cephalexin, erythromycin, or doxycycline

Occasionally, the bacteria causing the infection are resistant to treatment with the usual antibiotics (particularly, methicillin-resistant Staphylococcus aureus, MRSA). This can sometimes cause a more severe form of folliculitis. Depending on the circumstances, your doctor may consider more aggressive treatment that includes prescribing:

• A combination of two different oral antibiotics, including trimethoprim-sulfamethoxazole, clindamycin, amoxicillin, linezolid, or a tetracycline
• A topical medication, mupirocin ointment, to apply to the nostrils
• If your doctor prescribes antibiotics, be sure to take the full course of treatment to avoid allowing the bacteria to develop resistance to the antibiotic prescribed.