Abscess (redirected from Welch's abscess)

Abscess 

Definition

An abscess is an enclosed collection of liquefied tissue, known as pus, somewhere in the body. It is the result of the body's defensive reaction to foreign material.

Description

There are two types of abscesses, septic and sterile. Most abscesses are septic, which means that they are the result of an infection. Septic abscesses can occur anywhere in the body. Only a germ and the body's immune response are required. In response to the invading germ, white blood cells gather at the infected site and begin producing chemicals called enzymes that attack the germ by digesting it. These enzymes act like acid, killing the germs and breaking them down into small pieces that can be picked up by the circulation and eliminated from the body. Unfortunately, these chemicals also digest body tissues. In most cases, the germ produces similar chemicals. The result is a thick, yellow liquid—pus—containing digested germs, digested tissue, white blood cells, and enzymes.

An abscess is the last stage of a tissue infection that begins with a process called inflammation. Initially, as the invading germ activates the body's immune system, several events occur:

These four signs—heat, swelling, redness, and pain—characterize inflammation.

As the process progresses, the tissue begins to turn to liquid, and an abscess forms. It is the nature of an abscess to spread as the chemical digestion liquefies more and more tissue. Furthermore, the spreading follows the path of least resistance—the tissues most easily digested. A good example is an abscess just beneath the skin. It most easily continues along beneath the skin rather than working its way through the skin where it could drain its toxic contents. The contents of the abscess also leak into the general circulation and produce symptoms just like any other infection. These include chills, fever, aching, and general discomfort.

Sterile abscesses are sometimes a milder form of the same process caused not by germs but by nonliving irritants such as drugs. If an injected drug like penicillin is not absorbed, it stays where it was injected and may cause enough irritation to generate a sterile abscess—sterile because there is no infection involved. Sterile abscesses are quite likely to turn into hard, solid lumps as they scar, rather than remaining pockets of pus.

Causes and symptoms

Many different agents cause abscesses. The most common are the pus-forming (pyogenic) bacteria like Staphylococcus aureus, which is nearly always the cause of abscesses under the skin. Abscesses near the large bowel, particularly around the anus, may be caused by any of the numerous bacteria found within the large bowel. Brain abscesses and liver abscesses can be caused by any organism that can travel there through the circulation. Bacteria, amoeba, and certain fungi can travel in this fashion. Abscesses in other parts of the body are caused by organisms that normally inhabit nearby structures or that infect them. Some common causes of specific abscesses are:

Specific types of abscesses

Listed below are some of the more common and important abscesses.

Key terms

Cellulitis — Inflammation of tissue due to infection.

Enzyme — Any of a number of protein chemicals that can change other chemicals.

Fallopian tubes — Part of the internal female anatomy that carries eggs from the ovaries to the uterus.

Flora — Living inhabitants of a region or area.

Pyogenic — Capable of generating pus. Streptococcus, Staphocococcus, and bowel bacteria are the primary pyogenic organisms.

Sebaceous glands — —Tiny structures in the skin that produce oil (sebum). If they become plugged, sebum collects inside and forms a nurturing place for germs to grow.

Septicemia — The spread of an infectious agent throughout the body by means of the blood stream.

Sinus — A tubular channel connecting one body part with another or with the outside.

Diagnosis

The common findings of inflammation—heat, redness, swelling, and pain—easily identify superficial abscesses. Abscesses in other places may produce only generalized symptoms such as fever and discomfort. If the patient's symptoms and physical examination do not help, a physician may have to resort to a battery of tests to locate the site of an abscess, but usually something in the initial evaluation directs the search. Recent or chronic disease in an organ suggests it may be the site of an abscess. Dysfunction of an organ or system—for instance, seizures or altered bowel function—may provide the clue. Pain and tenderness on physical examination are common findings. Sometimes a deep abscess will eat a small channel (sinus) to the surface and begin leaking pus. A sterile abscess may cause only a painful lump deep in the buttock where a shot was given.

Treatment

Since skin is very resistant to the spread of infection, it acts as a barrier, often keeping the toxic chemicals of an abscess from escaping the body on their own. Thus, the pus must be drained from the abscess by a physician. The surgeon determines when the abscess is ready for drainage and opens a path to the outside, allowing the pus to escape. Ordinarily, the body handles the remaining infection, sometimes with the help of antibiotics or other drugs. The surgeon may leave a drain (a piece of cloth or rubber) in the abscess cavity to prevent it from closing before all the pus has drained out.

Alternative treatment

If an abscess is directly beneath the skin, it will be slowly working its way through the skin as it is more rapidly working its way elsewhere. Since chemicals work faster at higher temperatures, applications of hot compresses to the skin over the abscess will hasten the digestion of the skin and eventually result in its breaking down, releasing the pus spontaneously. This treatment is best reserved for smaller abscesses in relatively less dangerous areas of the body—limbs, trunk, back of the neck. It is also useful for all superficial abscesses in their very early stages. It will "ripen" them.

Contrast hydrotherapy, alternating hot and cold compresses, can also help assist the body in resorption of the abscess. There are two homeopathic remedies that work to rebalance the body in relation to abscess formation, Silica and Hepar sulphuris. In cases of septic abscesses, bentonite clay packs (bentonite clay and a small amount of Hydrastis powder) can be used to draw the infection from the area.

Prognosis

Once the abscess is properly drained, the prognosis is excellent for the condition itself. The reason for the abscess (other diseases the patient has) will determine the overall outcome. If, on the other hand, the abscess ruptures into neighboring areas or permits the infectious agent to spill into the bloodstream, serious or fatal consequences are likely. Abscesses in and around the nasal sinuses, face, ears, and scalp may work their way into the brain. Abscesses within an abdominal organ such as the liver may rupture into the abdominal cavity. In either case, the result is life threatening. Blood poisoning is a term commonly used to describe an infection that has spilled into the blood stream and spread throughout the body from a localized origin. Blood poisoning, known to physicians as septicemia, is also life threatening.

Of special note, abscesses in the hand are more serious than they might appear. Due to the intricate structure and the overriding importance of the hand, any hand infection must be treated promptly and competently.

Prevention

Infections that are treated early with heat (if superficial) or antibiotics will often resolve without the formation of an abscess. It is even better to avoid infections altogether by taking prompt care of open injuries, particularly puncture wounds. Bites are the most dangerous of all, even more so because they often occur on the hand.

Resources

Books

Fauci, Anthony S., et al., editors. Harrison's Principles of Internal Medicine. New York: McGraw-Hill, 1997.

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abscess /ab·scess/ (ab´ses) a localized collection of pus in a cavity formed by disintegration of tissues.

Cross section of abscess.

Abscesses of breast.

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amebic abscess  one caused by Entamoeba histolytica, usually occurring in the liver but also in the lungs, brain, and spleen.

apical abscess  a suppurative inflammatory reaction involving the tissues surrounding the apical portion of a tooth, occurring in acute and chronic forms.

appendiceal abscess , appendicular abscess one resulting from perforation of an acutely inflamed appendix.

Bezold's abscess  one deep in the neck as a complication of acute mastoiditis.

brain abscess  one affecting the brain as a result of extension of an infection (e.g., otitis media) from an adjacent area, or through bloodborne infection.

Brodie's abscess  a roughly spherical region of bone destruction, filled with pus or connective tissue, usually in the metaphyseal region of long bones and caused by Staphylococcus aureus or S. albus.

cold abscess 

1. one of slow development and with little inflammation.

2. tuberculous a.

diffuse abscess  a collection of pus not enclosed by a capsule.

gas abscess  one containing gas, caused by gas-forming bacteria such as Clostridium perfringens.

miliary abscess  one of a set of small multiple abscesses.

Pautrier's abscess  see under microabscess.

peritonsillar abscess  one in the connective tissue of the tonsil capsule, from suppuration of the tonsil.

phlegmonous abscess  one associated with acute inflammation of the subcutaneous connective tissue.

ring abscess  a ring-shaped purulent infiltration at the periphery of the cornea.

shirt-stud abscess  one separated into two cavities connected by a narrow channel.

stitch abscess  one developed about a stitch or suture.

thecal abscess  one arising in a sheath, as in a tendon sheath.

tuberculous abscess  one due to infection with tubercle bacilli.

vitreous abscess  an abscess of the vitreous humor of the eye due to infection, trauma, or foreign body.

wandering abscess  one that burrows into tissues and finally points at a distance from the site of origin.

Welch's abscess  gas a.

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ab·scess (bss)

n.

1. A collection of pus formed by tissue destruction in an inflamed area of a localized infection.

2. A cavity that is formed by liquefactive necrosis within solid tissue.

v.

To form an abscess.

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abscess (ab´ses),

n a localized accumulation of suppuration in a confined space formed by tissue disintegration.

Abscess.

abscess, alveolar,

n See periapical abscess.

abscess, apical,

n See periapical abscess.

abscess, dentoalveolar,

n See periapical abscess.

abscess, gingival,

n a superficial periodontal abscess occurring within the free gingival sulcus surrounding the tooth, frequently caused by the impaction of food.

abscess, lateral,

n See periodontal abscess.

abscess, periapical

n an abscess involving the apical region of the root, alveolus, and surrounding bone as a result of pulpal disease.

abscess, pericoronal,

n See pericoronitis.

abscess, periodontal,

n an abscess involving the attachment tissues and alveolar bone as a result of periodontal disease.

abscess, periradicular

n an abscess involving the periradicular region of the root, alveolus, and surrounding bone as a result of pulpal disease.

abscess, pulpal,

n an abscess occurring within pulpal tissue.

abscess, staphylococcal

n an abscess caused by the bacteria
S. aureus, an infectious agent that can be transmitted via saliva and other discharges of the body. The incubation period is 4 to 10 days; the duration of the abscess varies and is indefinite. The bacteria are communicable throughout the drainage period of the lesions and while the carrier state continues.

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abscess

a localized collection of pus in a cavity formed by the disintegration of tissue. Most abscesses are formed by invasion of tissues by bacteria, but some are caused by fungi or protozoa or even helminths, and some are sterile. Their effects are determined by their location and the pressure that they exert on nearby organs, and the degree of toxemia that they create from their bacterial content and the amount of tissue destroyed. So that for a reasonably active abscess the syndrome presented will be one of local pain, anorexia and fever, and a leukocytosis. For specific abscesses see under anatomical sites, e.g. brain abscess.

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Brodie's abscess

a circumscribed abscess in bone, caused by hematogenous infection that becomes a chronic nidus of infection.

cervical abscess

see vertebral abscess.

cold abscess

one of slow development and with little inflammation, e.g. caseous lymphadenitis of sheep and goat.

cornea stromal abscess

small ulcers or puncture wounds of the corneal epithelium may permit entry of bacteria then heal, creating an abscess. Particularly important in horses.

diffuse abscess

a collection of pus not enclosed by a capsule.

facial subcutaneous abscess

a disease of cattle eating hay or pasture containing mature grass awns.

gas abscess

one containing gas, caused by gas-forming bacteria such as Clostridium perfringens.

grass seed abscess

in cattle occurs as a cold, subcutaneous abscess at the throat or on the mandible and is often diagnosed but rarely confirmed. In dogs it occurs in many sites, but most commonly between the toes. The causative grass awn(s) may be recovered by forceps or, in more extensive lesions, surgical exploration.

infraorbital abscess

occurs in birds as a sequel to chronic upper respiratory infection with sinusitis.

injection site abscess

an iatrogenic lesion resulting from incomplete skin disinfection before injection; usually contains Arcanobacterium pyogenes.

intra-abdominal abscess

include diaphragmatic, mesenteric, retroperitoneal; many are subclinical; clinical signs include those of chronic peritonitis. Called also omental bursitis.

maxillary abscess

see malar abscess.

mediastinal abscess

a very large abscess in this site may cause signs of congestive heart failure due to compression of pericardium and venae cavae.

miliary abscess

one of a set of small abscesses.

milk abscess

abscess of the mammary gland occurring during lactation.

pectoral abscess

a disease of horses in which abscesses occur in the pectoral muscles and ventral midline, and in some cases in internal organs, causing local pain and swelling and eventually rupturing and draining to the exterior. Endemic to areas of California, Texas and Colorado in the USA where it is also known as pigeon fever and has epidemic occurrence in the autumn of some years with a possible insect vector transmission. Caused by Corynebacterium pseudotuberculosis.

periapical abscess

inflammation and destruction of dental pulp and surrounding tissues, including the periodontal membrane and alveolar bone. The radiographic appearance is a translucency of the tooth apex and adjacent alveolar bone. Most common in dogs.

periorbital abscess

firm masses above or below the eyes occur in birds as a sequel to chronic respiratory disease and sinusitis.

phlegmonous abscess

one associated with acute inflammation of the subcutaneous connective tissue.

phoenix abscess

acute recurrence of a chronic periapical lesion.

primary abscess

one formed at the seat of the infection.

rete mirabile abscess

see pituitary abscess.

retroarticular abscess

one located between the intermediate phalanx and the deep flexor tendon in the hooves of cattle. It may be caused by extension of infection from the navicular bursa or from suppurative arthritis of the distal interphalangeal joint.

retrobulbar abscess

behind the orbit of the eye; cause pain on opening of the mouth, chemosis and exophthalmos, protrusion of the nictitating membrane, and systemic signs of infection. Most common in dogs and cats.

stitch abscess, suture abscess

one developed about a stitch or suture.

vertebral body/epidural abscess

usually of cervical or lumbar vertebrae; causes compression of cord manifested by incoordination, paresis, paralysis.

wandering abscess

one that burrows into tissues and finally points at a distance from the site of origin.

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abscess Infectious disease A local accumulation of pus in tissues, organs or confined spaces, almost invariably due to an infection Microbiology The bacteria cultured from an abscess are largely a function of the region affected. Cf Abdominal abscess, Alveolar abscess, Amebic abscess, Apical abscess, Areolar gland abscess, Brain abscess, Brodie's abscess, Cold abscess, Collar button abscess, Collar-stud abscess, Crypt abscess, Intracranial abscess, Kogoj's abscess, Microabscess, Munro's microabscess, Perforating abscess, Peritonsillar abscess, Ring abscess, Satellite abscess, Stellate abscess, Walled abscess.