Symptoms

Signs

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A carbuncle is a red, swollen, and painful cluster of boils that are connected to each other under the skin.

A boil (or furuncle) is an infection of a hair follicle that has a small collection of pus (called an abscess) under the skin.

Usually single, a carbuncle is most likely to occur on a hairy area of the body such as the back or nape of the neck. But a carbuncle also can develop in other areas of the body such as the buttocks, thighs, groin, and armpits.

carbuncles

Most carbuncles are caused by Staphylococcus aureusbacteria, which inhabit the skin surface, throat, and nasal passages. These bacteria can cause infection by entering the skin through a hair follicle, small scrape, or puncture, although sometimes there is no obvious point of entry.

Filled with pus -- a mixture of old and white blood cells, bacteria, and dead skin cells -- carbuncles must drain before they're able to heal. Carbuncles are more likely than boils to leave scars.

An active boil or carbuncle is contagious: the infection can spread to other parts of the person's body or to other people through skin-to-skin contact or the sharing of personal items. So it's important to practice appropriate self-care measures, like keeping the area clean and covered, until the carbuncle drains and heals.

Carbuncles require medical treatment to prevent or manage complications, promote healing, and minimize scarring. Contact your doctor if you have a boil or boils that have persisted for more than a few days.

Risk Factors for Carbuncles

Older age, obesity, poor hygiene, and poor overall health are associated with carbuncles. Other risk factors for carbuncles include:

  • Chronic skin conditions, which damage the skin's protective barrier
  • Diabetes
  • Kidney disease
  • Liver disease
  • Any condition or treatment that weakens the immune system

Carbuncles also can occur in otherwise healthy, fit, younger people, especially those who live together in group settings such as college dorms and share items such as bed linens, towels, or clothing. In addition, people of any age can develop carbuncles from irritations or abrasions to the skin surface caused by tight clothing, shaving, or insect bites, especially in body areas with heavy perspiration.

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Complications of Injecting Drug Use

  • Local problems—Abscess (Figures 240-2 
    Image not available.

    A 32-year-old woman with type 1 diabetes developed large abscesses all over her body secondary to injection of cocaine and heroin. Her back shows the large scars remaining after the healing of these abscesses. (Courtesy of ­Richard P. Usatine, MD.)

    and 240-3; Abscess), cellulitis, septic thrombophlebitis, local induration, necrotizing fasciitis, gas gangrene, pyomyositis, mycotic aneurysm, compartmental syndromes, and foreign bodies (e.g., broken needle parts) in local areas.2
    • IDUs are at higher risk of getting methicillin-resistant Staphylococcus aureus(MRSA) skin infections that the patient may think are spider bites (Figure 240-4).
    • Some IDUs give up trying to inject into their veins and put the cocaine directly into the skin. This causes local skin necrosis that produces round atrophic scars (Figure 240-5).
  • IDUs are at risk for contracting systemic infections, including HIV and hepatitis B or hepatitis C.
    • Injecting drug users are at risk of endocarditis, osteomyelitis (Figures 240-6and 240-7), and an abscess of the epidural region. These infections can lead to long hospitalizations for intravenous antibiotics. The endocarditis that occurs in IDUs involves the right-sided heart valves (see Chapter 50, Bacterial Endocarditis).2 They are also at risk of septic emboli to the lungs, group A β-hemolytic streptococcal septicemia, septic arthritis, and candidal and other fungal infections.

 

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Question 1 of 1

A 42-year-old African-American man has been diagnosed with hypertension for the past 10 years and treated with medication. One morning, he is found unresponsive by his wife. He is taken to the emergency department and pronounced dead by the physician. An autopsy revealed cardiac hypertrophy and a narrowing of the aorta just distal to the ligamentum arteriosum, with dilation of the intercostal artery's ostia. How could the death have possibly been prevented?

Answer

 

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