Boil

A boil, also called a furuncle, is a deep folliculitis, infection of the hair follicle. It is almost always caused by infection by the bacterium Staphylococcus aureus, resulting in a painful swollen area on the skin caused by an accumulation of pus and dead tissue. Individual boils clustered together are called carbuncles. Staphylococcus is a genus of bacteria that is characterized by being round (coccus or spheroid shaped), Gram-positive, and found as either single cells, in pairs, or more frequently, in clusters that resemble a bunch of grapes. The genus name Staphylococcus is derived from Greek terms "staphyle and kokkos" that mean "a bunch of grapes", which is how the bacteria often appears microscopically (after Gram staining). In 1884, German physician Ottomar Rosenbach first described and named the bacteria. Two major divisions of the genus Staphylococcus are separated by the bacteria's ability to produce coagulase, an enzyme that can clot blood. Most human infections are caused by coagulase-positive S. aureus strains. Almost any organ system can be infected by S. aureus.

Signs and symptoms

Boils are bumpy red, pus-filled lumps around a hair follicle that are tender, warm, and very painful. They range from pea-sized to golf ball-sized. A yellow or white point at the center of the lump can be seen when the boil is ready to drain or discharge pus. In a severe infection, an individual may experience fever, swollen lymph nodes, and fatigue. A recurring boil is called chronic furunculosis. Skin infections tend to be recurrent in many patients and often spread to other family members. Systemic factors that lower resistance commonly are detectable, including: diabetes, obesity, and hematologic disorders.

Causes

Usually, the cause is bacteria such as staphylococci that are present on the skin. Bacterial colonization begins in the hair follicles and can cause local cellulitis and inflammation. Risk factors for furunculosis include bacterial carriage in the nostrils, diabetes mellitus, obesity, lymphoproliferative neoplasms, malnutrition, and use of immunosuppressive drugs. Patients with recurrent boils are as well more likely to have a positive family history, take antibiotics, and to have been hospitalized, anemic, or diabetic; they are also more likely to have associated skin diseases and multiple lesions.

Complications

The most common complications of boils are scarring and infection or abscess of the skin, spinal cord, brain, kidneys, or other organs. Infections may also spread to the bloodstream (sepsis) and become life-threatening. that may severely harm or kill the infected person. S. aureus strains also produce enzymes and exotoxins (both secreted by staph) that likely cause or increase the severity of certain diseases. Such diseases include food poisoning, septic shock, toxic shock syndrome, and scalded skin syndrome. Almost any organ system can be infected by S. aureus.

Treatment

In contrast to common belief, boils do not need to be drained in order to heal; in fact opening the affected skin area can cause further infections. In some instance however, draining can be encouraged by application of a cloth soaked in warm salt water. Washing and covering the furuncle with antibiotic cream or antiseptic tea tree oil and a bandage also promotes healing. Furuncles should never be squeezed or lanced without the oversight of a medical practitioner because it may spread the infection. Poor personal hygiene being common, the role of nasal S. aureus carrier may differ from communities with good hygienic practices. Staphylococcus aureus re-infection may result from contact with infected family members, contaminated fomites, or from other extra-nasal sites. This raises a suggestion to treat household contacts and close contacts if recurrence persists, because it is likely that one or more contacts are asymptomatic carriers of S. aureus. In addition to the increase in the cost of treatment in poor countries, the possibility of developing drug resistance must be considered. The most important independent predictor of recurrence is a positive family history. Boils are spread among individuals by touching or bursting a boil. Furunculosis is a common disease, particularly with deficient hygiene. A large number of S. aureus organisms are frequently present on the sheets and underclothing of patients with furunculosis and may cause re-infection of patients and infection of other members of the family. A variety of host factors, such as abnormal neutrophil chemotaxis, deficient intra-cellular killing, and immuno-deficient states are of importance in a minority of patients with recurrent furunculosis. Health education about sound personal hygiene and correction of anemia should be mandatory in management of furunculosis. A previous study reported that MRSA infection was significantly associated with poor personal hygiene. It was reported that frequent hand and body washing with water and antimicrobial soap solution decreases staphylococcus skin colonization. Previous use of antibiotics is associated with a high risk of recurrence. This may be due to the development of resistance to the antibiotics used. An associated skin disease favors recurrence. This may be attributed to the persistent colonization of abnormal skin with S. aureus strains, such as is the case in patients with atopic dermatitis.

See also

Hospital furunculosis

Japanese spotted fever

List of cutaneous conditions

References

External links

Category:Bacterium-related cutaneous conditions