Chapter 97. Skin Problems in Ostomates

A stoma is a surgically created opening onto the skin of part of the gastrointestinal or urinary tract in order to drain the effluent from that viscus. The most frequently performed stomas are ileostomies, colostomies, and ileal conduits (urostomies or urinary diversion). The commonest indications for stoma surgery are inflammatory bowel disease, malignancy and neurological problems. A patient with a stoma is usually termed an “ostomist” or “ostomate.”

Epidemiology

There are estimated to be more than 1.4 million ostomates in the United States and 100,000 in the United Kingdom and Ireland. Some stomas are temporary, with surgical anastomosis delayed, pending resolution of the acute disorder. Temporary stomas are often “loop stomas” where a loop of bowel is brought to the skin surface and part of the wall removed to allow preferential drainage into a stoma pouch in order to relieve a distal problem, for example, perianal ulceration. Such stomas are more frequently associated with skin problems secondary to leaks.1 Many stomas formed for malignant indications can be seen as palliative procedures.

A stoma appliance is essentially a device for collecting stoma effluent with a high degree of comfort and security until it can be disposed of. There continues to be promising advances in the design of stoma bags. Essentially, the device is a pouch or bag held in place over the stoma by an adhesive skin barrier made solely or partly from hydrocolloid. Many ileostomists and urostomists use two-piece appliances where the barrier remains on the skin for 2–4 days and is detachable; disposable bags are changed as necessary. Appliances with convexity on the surface next to the skin are available for patients with short or buried stomas (Fig. 97-1). Useful recent innovations include softer convex appliance that apply less pressure on the skin and collars or sleeves that fit snugly around the stoma before applying the bag thereby reducing the chance of leaks of effluent or intestinal mucus under the barrier.

As many as two-thirds of ostomates experience skin problems that interfere with the normal use of their stoma appliance,2,3 and such dermatoses are the commonest reasons for a visit to outpatient stoma services.4,5 The majority of these problems are irritant reactions, usually dermatitis secondary to leaks from the stoma; however, there are also a number of other well-defined irritant reactions. Common coincidental dermatoses, particularly psoriasis and constitutional eczema, account for around 15% of the diseases seen.2,6 An approach to diagnosing peristomal dermatoses is given in eFigure 97-1.1.

Irritant Reactions

Dermatitis

Dermatitis most frequently results from the chronic leakage of effluent onto the skin because the patient is using an inappropriately shaped appliance or one with too large a hole for their stoma. The most common cause is the remodeling of the stoma and abdominal wall that occurs in the months after surgery, whereby a stoma usually becomes a little shorter and thinner, resulting in leaks unless a correctly fitting appliance is selected (Figs. 97-2, 97-3, 97-4, 97-5, and 97-6). Leaks will also occur when patients gain a lot of weight after surgery and the effective length of their stoma diminishes because it becomes buried by subcutaneous fat.7 Irregular scarring after surgery or retraction of the stoma, may also be associated with chronic leakage. Such irregularities can be corrected with topically applied pastes. One effective alternative is to use collagen fillers (Porcine collagen Permacol™)8 to recontour the skin surface. Short stomas (<2 cm long), loop ileostomies and stomas formed as emergency procedures are more likely to be associated with skin problems.1,9 Chronically irritated skin can become markedly hyperkeratotic and acanthotic (Fig. 97-7). These problems can be prevented and resolved by careful postsurgical follow-up by the enterostomal therapist (ET; stoma nurse specialist) to ensure that the correct appliance is being used. Severe, acute irritant dermatitis can be effectively treated with a short course of topical corticosteroid while longer term appliance modifications are being undertaken (Table 97-1).

Anxieties about possible leaks and odors can lead to excessively frequent bag changing, which may cause an irritant dermatitis by stripping the skin. Patients may, for the same reasons, wear waist belts too tightly thereby causing pressure damage even ulcers (eFig. 97-7.1) and occasionally necrosis. Whatever the cause of skin inflammation, a vicious cycle can develop when the damaged skin prevents proper bag adhesion necessitating more frequent bag changes.12 Careful counseling is usually necessary in order to reassure the patient regarding leaks.

Approximately 15% of ostomates with skin problems suffer from a chronic or recurrent dermatitis for which no irritant, allergic, or infective cause can be found, and where primary skin disease is ruled out.2 In the absence of a primary treatable cause, the use of topical corticosteroid lotions is appropriate. Most patients require only occasional short courses for a maximum of 4 weeks’ duration (Table 97-1). A small number of patients require intermittent applications longer term. Provided that the frequency of application is no more than once every 10 days, steroid atrophy of the skin appears to be unusual.

In ileostomy patients with short bowel, the output may be very high and corrosive due to the enzyme and bile salt content. In this situation, some leaks are inevitable, despite the use of proprietary barrier preparations or soothing lotions. Where the irritation has resulted in an eroded dermatitis, sucralfate powder applied at every stoma bag change can be very effective. In addition to forming a sticky barrier, the preparation is thought to promote healing.13 Surgical scars and even large striae (eFig. 97-7.2) can lead to ulcerations and bag failures, which may respond to topical carmellose sodium or sucralfate powders. Wound dehiscence can cause severe difficulties for bag adhesion (eFig. 97-7.3) and presents particular challenges for nursing management where the dermatologist may be called upon for advice as part of the multidisciplinary team.14

Chronic Papillomatous Dermatitis

This term refers to clinical appearance of warty excrescences around urostomies resulting from leaks and pooling of urine on the peristomal skin (eFig. 97-7.4). Recurrent urinary tract infections appear to increase the likelihood of chronic papillomatous dermatitis (CPD) probably due to the presence of ammonia from urea-splitting bacteria. Histologically, there is massive hyperkeratosis and acanthosis. Pseudoepitheliomatous hyperplasia may also be a feature but is not universal. The histology is therefore not specific and comparable to that of other irritant reactions. Verrucous lesions with similar appearances are occasionally seen affecting ileostomies15 (Fig. 97-5). In severe cases, the lesions can encroach on the stoma and cause stenosis (Fig. 97-8). When the leaking of urine is caused by a receding stoma, CPD will resolve rapidly if a convex-backed appliance is used to increase the effective length of the urostomy and thereby stop leaks. Acetic acid soaks (10% domestic vinegar in water)16 at each bag change are effective in some cases (eFig. 97-8.1). Larger excrescences may be shaved off under local anesthetic to allow a bag with a smaller aperture to be used. In severe cases, surgical revision of the stoma may be required.

Granulomas

The term granuloma is commonly used for a range of papular lesions, which are almost all secondary to irritation. The authors have only seen the condition affecting ileostomies or colostomies and not urostomies. They may affect the stoma itself (inflammatory colonic or ileal polyps) or the mucocutaneous junction, or may be found more widely, extending onto the peristomal skin (Fig. 97-9). The latter is more frequent in patients with colostomies, and in this situation, the papules may become very extensive. This occurs when the patient enlarges the stoma bag aperture to accommodate a papule, thereby exposing normal skin to fecal irritation, which precipitates further lesions and prompts the patient to enlarge the aperture still further (eFig. 97-9.1). Histologically, the lesions contain a chronic inflammatory infiltrate, granulation tissue, and sometimes metaplastic bowel mucosa where the metaplasia is probably a response to fecal irritation. Comparable lesions occur around ileostomies (eFig. 97-9.2) but are generally flatter and may even present as sheets of cherry-red granulation tissue. These lesions are sometimes caused by seeding mucosa at the time of surgery.17 The majority, however, probably represent mucosal metaplasia as a consequence of persistent fecal contact with the skin. In long-standing ileostomies (greater than 10 years), there is a small risk of malignant change analogous to Barrett esophagus.18 A biopsy to rule out malignant change should be considered for unusual lesions particularly ulcerative changes in existing granulomas around ileostomies.

Asymptomatic, solitary lesions can be left. Where they are painful19 or bleed easily leading to poor stoma bag adhesion, they can be destroyed by cautery (thermal or silver nitrate) or by cryotherapy, using a liquid nitrogen spray. Larger and proliferating lesions especially around colostomies are best removed by shave and cautery under local anesthetic and an appliance with a correctly sized aperture fitted in order to prevent massive proliferation. Laser ablation is increasingly regarded as a first-line treatment being less painful and possibly more effective.20

Psoriasis

Psoriasis is a common cause of peristomal skin disease because it may appear in irritated or traumatized skin (Koebner's phenomenon) and because it is associated with inflammatory bowel disease (Chapter 18). Peristomal psoriasis presents as a glazed erythema similar to flexural psoriasis (eFig. 97-9.3) and can be treated in the same way with topical corticosteroids although, at the peristomal site, a nongreasy base should be selected (Table 97-1). The diagnosis is usually unmistakable being part of more generalized involvement (eFig. 97-9.4) but localized peristomal involvement is described.21 Resolution of psoriasis under hydrocolloid occlusion has been described,22 which is of relevance to stoma patients because 50% of cases of peristomal psoriasis will resolve if a bag is selected with a thicker, hydrocolloid-only barrier. Where the patient can tolerate the stoma being temporarily unprotected from leaks, ultraviolet (UV) phototherapy is effective as for psoriasis elsewhere. The mucous membranes of the stoma should be protected from UV light. Although irritating topical psoriasis treatments are not usually tolerated, some patients have had success with creams containing hydrocortisone 1% and coal tar 3%, the application being left on the skin for 1 hour each day (Table 97-1, Point 3). Superficial X-ray (Grenz-ray) therapy has been used in recalcitrant cases.

Infections

The most frequent peristomal skin infection is staphylococcal folliculitis, usually, but not exclusively, in those individuals with hairy abdomens who shave regularly to help the bags stick (eFig. 97-9.5). It responds to oral antibiotics and to a reduction in shaving frequency to no more than once per week. Although antiseptic washes can be a useful additional therapeutic measure, they can cause irritant reactions if the skin is not correctly rinsed before being occluded by the stoma bag. Localized skin infections, usually staphylococcal or streptococcal, can produce a rash indistinguishable from irritant dermatitis or primary skin disease such as psoriasis or eczema. Furthermore, preexisting psoriasis or eczema can become secondarily infected under occlusion (eFig. 97-9.6). Therefore, all peristomal rashes should be swabbed for microbiological investigation and appropriate antibiotics prescribed based on microbiological sensitivities. In tropical climates, cutaneous fungal infections are common, whereas in more temperate regions, Candida albicans is an occasional problem and dermatophyte infection is rare. Viral warts are occasionally seen and can present as verrucous lesions solely affecting the stoma itself (eFig. 97-9.7). Despite the body site and the presence of skin trauma herpes zoster is surprisingly uncommon around stomas. Nonetheless viral infections should be considered in the differential diagnosis of vesicular eruptions and where there are peristomal erosions because vesicles and bullae are typically deroofed by removing stoma bags and, therefore, are not commonly observed (eFig. 97-9.8).

Pyoderma Gangrenosum

This rare, inflammatory, ulcerative neutrophilic dermatosis (see Chapter 33) is more common in peristomal skin than would be expected from its frequency in the general population.23,24 Clearly, this is partly due to its strong association with inflammatory bowel disease. There is some evidence, however, that the increased use of convex-backed appliances may contribute to the incidence via the pathergic effect of increased pressure on the skin. We have seen a decline in incidence of peristomal PG in the last 5 years associated with reduced use of deeply convex appliances and the introduction of softer convex materials. Although some cases of pyoderma gangrenosum (PG) are associated with active inflammatory bowel disease,25 the association is not universal; indeed, peristomal PG occurs in ostomates who have no history of inflammatory bowel disease.26 Peristomal PG presents as a painful papule or pustule, often hemorrhagic, which then ulcerates and is usually very painful (eFigs. 97-9.8 and 97-9.9). The pain and the ulceration can have profound effects on the patient's ability to wear a bag and, therefore, on their quality of life. The ulcers heal with cribriform scarring (eFigs. 97-9.10 and 97-9.11) that can itself impair bag adhesion so that rapid, effective treatment of PG is essential.

Management is similar to that for PG elsewhere (Chapter 33) although small, superficial, and solitary ulcers respond very rapidly to topical therapy alone (eFig. 97-9.12). Because of the problems with greasy preparations causing lifting of stoma bags, alternative vehicles are usually necessary (Table 97-1). There are no randomized controlled trials of treatment for this rare condition and some current evidence has recently been reviewed.27 The author's approach is detailed in Table 97-2.

Contact Allergy

Modern stoma bags are made largely from food-grade materials and those with a low potential for sensitization. Nonetheless, there are case reports of sensitivities to individual ingredients including Gantrez® (GAF Corporation. Wayne NJ) resins and acrylate adhesive systems (eFig. 97-9.13). Furthermore, there is a potential for contact allergy from deodorizers and topically applied preparations. These case reports of peristomal allergic contact dermatitis have recently been the subject of a literature review.34 Despite the fact that contact allergy is a relatively uncommon cause of peristomal dermatitis most patients and many health professionals regard contact hypersensitivity to their appliance as the likely cause of a peristomal rash. Patch testing is indicated in patients with persisting problems where infection, irritation, and constitutional skin disease has been ruled out.35 We have patch tested well over 100 such patients and relevant positive allergic reactions were found in only three cases of topically applied materials including fragrance in a deodorizer and biocides in wet wipes.

Other Conditions

In theory, almost any of the multitude of skin disorders might affect a stoma. In clinical practice, the common disorders (e.g., psoriasis predominate and others) are more common than expected (e.g., PG). Some less common peristomal dermatoses are worthy of note either because they present practical difficulties such as pemphigoid and nicorandil ulceration, or in the case of lichen sclerosus because they have an unusual predilection for this site. The authors have managed five patients with pemphigoid affecting the skin around stomas (eFig. 97-9.14); in all cases, the principal problems are pain and the failure of stoma bag adhesion (eFig. 97-9.15). This necessitates a low threshold for rapidly effective systemic therapy (Chapter 56) otherwise the patient is rendered immobile in order to reduce the effect of a leaking stoma. Cecchi et al have summarized the clinical features and therapy of their own plus five previously published cases.36

Nicorandil, a potassium channel activator with nitrate activity is used in the management of angina. It has been associated with mouth ulceration as well as perianal,37 peristomal and even small bowel ulceration.38 It presents as rather indolent ulcers with minimal inflammation clinically or histologically. In a patient with pericolostomy ulcers that has had the stoma formed because of intractable perianal ulcers, for example, the diagnosis is usually straightforward. There are, however, a range of differential diagnoses for nonspecific ulceration including simple trauma such as one sees in patients with parastomal hernias that cause stretching and tearing of the skin. The diagnosis should be considered in patients receiving nicorandil with otherwise unexplained ulceration around a stoma. In most cases, the ulceration resolves within a month or two of stopping the drug (eFig. 97-9.16).

Lichen sclerosus affecting peristomal skin is an enigmatic condition as it can present in the absence of genital involvement and affect any type of stoma.39–41 In the authors’ experience of six cases (eFig. 97-9.17), the condition is painful and readily ulcerates. Topical corticosteroid therapy may be ineffective and intralesional steroid may be required (eFig. 97-9.17). Stoma surgery is avoided if at all possible in patients with inherited conditions that are associated with skin fragility or blistering. These conditions together with the more severe congenital ichthyoses can cause significant difficulties with proper stoma bag adhesion.

Benign tumours, particularly seborrheic keratoses, sometimes cause problems if they become inflamed or infected under the occlusion of a stoma appliance. In these circumstances, ablative treatment with simple curettage and cautery is effective.

Other conditions occasionally seen around stomas include Crohn disease, metstatic ulcerative colitis,42 basal cell carcinoma,43 squamous carcinoma,44 and metastatic adenocarcinoma.45