An ulcer is a discontinuity of an epithelial surface. There is usually progressive destruction of surface tissue, cell by cell, as distinct from death of macroscopic portions, e.g. gangrene or necrosis. Ulcers are classified as nonspecific, specific (e.g. tuberculous or syphilitic) or malignant.
Nonspecific ulcers are due to infection of wounds, or physical or chemical agents. Local irritation, as in the case of a dental ulcer, or interference with the circulation, e.g. varicose veins, are predisposing causes.
Trophic ulcers [trophe (Greek) = nutrition] are due to an impairment of the nutrition of the tissues, which depends upon an adequate blood supply and a properly functioning nerve supply. Ischaemia and anaesthesia therefore will cause these ulcers. Thus, in the arm, chronic vasospasm and syringomyelia will cause ulceration of the tips of the fingers (respectively painful and painless). In the leg, painful ischaemic ulcers occur around the ankle or on the dorsum of the foot. Neuropathic ulcers due to anaesthesia (diabetic neuritis, spina bifida, tabes dorsalis, leprosy or a peripheral nerve injury) are often called perforating ulcers . Starting in a corn or bunion, they penetrate the foot, and the suppuration may involve the bones and joints and spread along fascial planes upwards, even involving the calf.
The life history of an ulcer consists of three phases.
During the stage of extension the floor is covered with exudate and sloughs, while the base is indurated. The discharge is purulent and even blood stained.
The transition stage prepares for healing. The floor becomes cleaner, the sloughs separate, induration of the base diminishes and the discharge becomes more serous. Small, reddish areas of granulation tissue appear on the floor and these link up until the whole surface is covered.
The stage of repair consists of the transformation of granulation to fibrous tissue, which gradually contracts to form a scar. The epithelium gradually extends from the now shelving edge to cover the floor (at a rate of 1 mm per day).
This healing edge consists of three zones — an outer of epithelium, which appears white, a middle one, bluish in colour (where granulation tissue is covered by a few layers of epithelium), and an inner reddish zone of granulation tissue covered by a single layer of epithelial cells. The red colour of granulation tissue is due to the high density of new capillaries (neo-angiogenesis).
Clinical examination of an ulcer
This should be conducted in a systematic manner. The following are, with brief examples, the points which should be noted.
Site, e.g. 95 per cent of rodent ulcers occur on the upper part of the face. Carcinoma typically affects the lower lip, while a primary chancre of syphilis is usually on the upper lip.
• Size, particularly in relation to the length of history, e.g. a carcinoma extends more rapidly than a rodent ulcer, but more slowly than an inflammatory ulcer.
• Shape, e.g. a rodent ulcer is usually circular. A gummatous ulcer is typically circular, or serpiginous due to the fusion of multiple circles. An ulcer with a square area or straight edge is suggestive of ‘dermatitis artefacta’ .
• Edge. A healing, nonspecific ulcer has a shelving edge. It is pearly, rolled or rampant if a rodent ulcer, and raised and everted if an epithelioma, undermined and often bluish if tuberculous, vertically punched out if syphilitic.
• Floor. The floor is that which is seen by an observer, e.g. watery or apple-jelly granulations in a tuberculous ulcer, a wash-leather slough in a gummatous ulcer.
• Base. The base is what can be palpated. It may be indurated as in a carcinoma or attached to deep structures, e.g. a varicose ulcer to the tibia.
• Discharge. A purulent discharge indicates active infection. A blue—green coloration suggests infection with Pseudomonas pyocyaneus. A watery discharge is typical of tuberculosis. It is bloodstained in the extension phase of a nonspecific ulcer. Bacteriological examination may reveal colonisation by coagulase-positive staphylococci. Spirochetes are found in a primary chancre .
• Lymph nodes are not enlarged in the case of a rodent ulcer, unless due to secondary infection. In the case of carcinoma, they may be enlarged, hard and even fixed. The inguinal nodes draining a syphilitic chancre of the penis are firm and ‘shotty’, but contrarily the submandibular nodes draining a chancre of the lip are greatly enlarged.
• Pain. Nonspecific ulcers in the extension and transition stages are painful (except for the anaesthetic trophic type). Tuberculous ulcers vary, that of the tongue being very painful. Syphilitic ulcers are usually painless, but an anal chancre (of a homosexual) may be painful (cf. anal fissure).
• General examination. Evidence of debility, cardiac failure, all types of anaemia, including sickle-cell anaemia, or diabetes must be sought.
• Pathological examinations, e.g. biopsy, will confirm carcinoma. The serological and Mantoux tests may be of value for syphilis and tuberculosis, respectively.
• Marjolin’s ulcer.
Local (topical) treatment of nonspecific ulcers
Any underlying cause is treated, e.g. varicose veins, diabetes, arterial disease. Many lotions and nonadhesive applications are used to aid the separation of sloughs, hasten granulation and stimulate epithelialisation. The basic requirements of an ideal dressing are that should:
•maintain a high humidity between the wound and the dressing;
•remove excess exudate and toxic compounds;
•permit gaseous exchange of oxygen, carbon dioxide and water vapour;
•provide thermal insulation to the wound surface and be impermeable to microorganisms;
•be free from particles and toxic wound contaminants
•allow easy removal with no trauma at dressing change;
•be safe to use and be acceptable to the patient;
Antiseptics and topical antibiotics
Antiseptics can do more harm than good when used inappropriately. They can interfere with the normal healing process, are toxic to fibroblasts and may permit more virulent organisms to dominate. The routine use of antiseptic and hypochlorite solutions should be avoided. If a wound needs cleaning, this can be achieved safely and more economically with normal saline warmed to body temperature prior to use. If a topical antiseptic is necessary, aqueous chlorhexidine 1 in 5000 solution is effective against a wide range of Gram-positive and -negative organisms and some fungi, but not spores. Povidone iodine has a broad spectrum of activity but its antibacterial effect is reduced by contact with pus or exudate. It should not be used on patients who are sensitive to iodine. Topical antibiotics are not recommended routinely as resistance and sensitisation following application may arise. Flamazine is a hydrophilic cream containing silver sulphadiazine 1% which is a broad-spectrum antibacterial agent and very effective against Pseudomonas, useful for the prevention of Gram-negative sepsis in patients with severe burns.
Hydrocolloid dressings such as Granuflex or Comfeel consist of a thin polyurethane foam sheet bonded on to a semipermeable polyurethane film, which is impermeable to exudate and microorganisms. When the dressing comes into contact with wound exudate it interacts to form a gel which expands into the wound. The moist conditions produced under the dressing promote angiogenesis and wound healing without causing maceration. They can be used in the treatment of leg ulcers, pressure sores, minor burns and many types of granulating wound. A hydrocolloid dressing can be applied to small wounds containing dry slough or necrosis: the dressing prevents the loss of water vapour from the surface of the skin, and this effectively rehydrates the dead tissue which is then removed by autolysis.
Hydrogel (Intrasite gel) is a pale yellow/colourless transparent aqueous gel. When it comes into contact with a wound, the dressing absorbs excess exudate and produces a moist environment at the surface of the wound without causing tissue maceration. It may be applied to many different wounds including leg ulcers, pressure sores, surgical wounds and granulating tissue. It is particularly useful in the treatment of dry, sloughy or necrotic wounds, promoting rapid débridement by facilitating rehydration and autolysis of dead tissue. It reduces the feeling of pain and can be used as a carrier of other medicines, e.g. metronidazole, for the control of odour caused by infection with sensitive organisms. (It is useful in fungating tumours where the aim is not to heal the wound but to manage the distressing symptoms caused by it.) Intrasite should be secured with a secondary dressing such as an absorbent pad or Tegaderm depending on the wound.
Alginates (Kaltostat) consist of an absorbent fibrous fleece composed of the mixed sodium and calcium salts of alginic acid. In the presence of exudate or other body fluids containing sodium ions, the fibres absorb liquid and swell, calcium ions present in the fibre are partially replaced by sodium, causing the dressing to take on a gel-like appearance which promotes healing. The fibres are held in place with a secondary dressing such as an absorbent pad or Tegaderm depending on the amount of
exudate. Alginate dressings can be used for the management of bleeding wounds including cuts and lacerations and also for a wide range of exuding lesions including leg ulcers, pressure sores and most other granulating wounds. Most suitable for heavy to moderately exudating wounds. In the presence of low exudate the Kaltostat must be moistened with saline before application to avoid adherence. The alginates are biodegradable so it is not necessary to remove every fibre if it will damage the healing tissue.
Lyofoam is a low-adherent conformable polyurethane foam sheet. The side of the dressing that is to be placed in contact with the skin has been heat treated to render it hydrophilic, whilst the outer surface remains hydrophobic. The dressing is freely permeable to gases and water vapour but resists the penetration of aqueous solutions and exudate. The dressing absorbs blood and any other tissue fluids but the aqueous component is lost by evaporation through the back of the dressing. Strike-through occurs laterally and not at the top of the dressing. The dressing maintains a moist warm environment at the surface of the wound, which is conducive to granulation and epithelialisation. Foam sheet dressings may be used on a variety of exudating wounds including leg ulcers, pressure sores, sutured wounds, burns and donor sites.
Tegaderm consists of a thin polyurethane membrane coated with a layer of an acrylic adhesive. The dressing allows for a moist environment at the surface of the wound by reducing water vapour loss from the exposed tissue. It is permeable to both water vapour and oxygen and impermeable to microorganisms, providing an effective barrier to external contamination. Scab formation is prevented and epidermal regeneration takes place at an enhanced rate, compared with that which occurs in wounds treated with traditional dry dressings. Tegaderm may be used in the treatment of minor burns, pressure areas, donor sites, postoperative wounds and a variety of minor injuries. It is also effectively used as a protective cover to prevent skin breakdown due to friction or continuous exposure to moisture.
Alleyvncavity wound dressing is a highly comfortable absorbent dressing consisting of a soft, polymeric outer membrane with a three-dimensional honeycomb-like structure containing a mass of hydrophilic polyurethane chips. The outer membrane is perforated to allow exudate to be drawn into the interior of the dressing where it is absorbed and retained by the ‘chips’. This type of dressing is used for heavily exudating, full-thickness sloughy wounds, usually combined with Intrasite gel; it can be used alone with clean, deep, ex~ daring wounds.
Most of the above dressings are also available with added properties which improve their basic function, such as Kaltocarb. This is Kaltostat with a layer of activated charcoal cloth attached. This is effective as a primary dressing in the management of infected malodorous wounds.
As the wound heals if granulation tissue continues to grow past the epidermal layer, the dressing used to stimulate granulation should be discontinued and a Lyofoam dressing should be applied. If after 1 week there is no improvement Tetra-cortil ointment containing hydrocortisone and oxytetracycline applied sparingly to the wound may be effective. This should be covered with a Lyofoam dressing and should be used for no longer than 5 days. Silver nitrate may be used with heavy overgranulating tissue but it is not recommended, usually because of its toxicity and the risk of sensitivity and staining.
Oriental sore (syn. Delhi boil, Baghdad sore, etc.)
This disease is due to infection by a protozoal parasite, Leishmania tro pica, and is a common condition in Eastern countries which is occasionally imported to Western zones. An indurated papule appears on an exposed surface, usually the face. If untreated, this breaks down to form an indolent ulcer, which eventually leaves an ugly, pigmented scar. The condition readily responds to intravenous injections of antimony tartrate, but very small lesions can be treated by carbon dioxide snow, and also curettage.
Bazin’s disease (syn. erythema induratum) is due to localised areas of fat necrosis and particularly affects adolescent girls. Symmetrical purplish nodules appear, especially on the calves, and gradually break down to form indolent ulcers, which leave in their wake pigmented scars. Tuberculosis may be a cause in many instances, the ulcers responding to antituberculous drugs.
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