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Connective tissue disorders

Connective tissue disorders

Connective tissue disorders are a heterogenous group of conditions that affect multiple organ systems, including the skin, and are characterised by diverse patterns of autoantibody production. While the disorders may have overlapping and shared clinical features, there are often distinctive, and sometimes diagnostic, cutaneous findings.

Lupus erythematosus

There are 3 major clinical variants of lupus erythematosus—chronic cutaneous (discoid) lupus erythematosus; subacute cutaneous lupus erythematosus; and systemic lupus erythematosus (SLE), which is a multisystem disease that commonly affects the skin. Most forms of lupus erythematosus demonstrate photosensitivity to some degree. Lupus erythematosus is particularly hazardous in pregnancy, for both the mother and child.

The characteristic lesion of chronic cutaneous (discoid) lupus erythematosus is a well-defined red scaly plaque with prominent follicular plugging. The rash most commonly occurs on the sun-exposed areas of the face, neck, scalp, hands and forearms. Older lesions may show hyperpigmentation or hypopigmentation, and atrophic scarring, which on the scalp will produce alopecia. Early and adequate treatment is essential to avoid the risk of permanent scarring in cosmetically sensitive areas. Discoid lesions develop in approximately 20% of patients with SLE. The risk of a patient presenting with discoid lesions progressing to SLE is approximately 5% and is more likely if high-titre antinuclear antibodies are present or if the discoid lesions are disseminated.

Assessment requires a full history, examination and appropriate laboratory investigations to determine the presence and extent of systemic disease. A skin biopsy with immunofluorescence will confirm the diagnosis.

Sun protection is the cornerstone of treatment. Advise patients to wear long-sleeved shirts and broad-brimmed hats and use a broad-spectrum SPF 30+ sunscreen (see Prevention of sun-related tumours).

Lesions can be controlled and sometimes resolve with topical therapy alone. Use systemic treatment if control with topical agents is inadequate.

Commence treatment with

Reduce frequency of application and potency of the topical corticosteroid after initial improvement.

For hypertrophic or resistant lesions, use

For disseminated lesions or unresponsive disease, use

Response to antimalarials may take 4 to 6 weeks. If effective and tolerated, organise early eye review and then 12-monthly eye examinations during treatment to check for antimalarial retinopathy. Contraception is important for female patients.

Oral prednisolone can be used as an alternative or as an adjunct to antimalarial drugs. Use

Rarely, other forms of systemic therapy may be needed, including dapsone, clofazimine, acitretin, higher dose corticosteroids, methotrexate, azathioprine, thalidomide or auranofin.

The typical rash of subacute cutaneous lupus is either papulosquamous or annular, and atrophy and scarring do not occur. Up to 20% of patients with subacute lupus also have a few typical discoid lesions. Alopecia, (nonscarring) mucosal ulceration, livedo and telangiectasia may occur. Fever, malaise and constitutional symptoms may occur, but renal involvement is rare. This relatively benign subset of lupus erythematosus can usually be controlled with solar protection, topical corticosteroids and oral antimalarials, as for chronic cutaneous (discoid) lupus erythematosus.

If systemic involvement occurs, the full range of therapeutic options available for SLE may be used.

Systemic lupus erythematosus (SLE) is a multisystem disease that often requires a multidisciplinary approach. The typical rash consists of erythema and oedema over the bridge of the nose extending onto the cheeks (butterfly rash). A full discussion of the skin signs of SLE is beyond the scope of these guidelines.

Photoprotection is essential in all patients. Oral therapy for control of systemic disease may resolve cutaneous manifestations. If lesions persist despite oral therapy for internal disease, any of the topical or oral therapies discussed for chronic cutaneous (discoid) lupus erythematosus may be used.

 Scleroderma

Scleroderma includes a group of diseases characterised by the deposition of excessive amounts of collagen in a variety of tissues, including the skin. Scleroderma can be classified as localised (morphoea) or systemic, as in progressive systemic sclerosis. Patients with calcinosis, Raynaud’s phenomenon, oesophageal dysmotility, sclerodactyly and telangiectasia have CREST syndrome, which is probably a subgroup of systemic sclerosis.

Localised scleroderma, also known as morphoea, is the most common form of the disease. Morphoea presents as one or more indurated plaques and has a self-limiting course. The initial faint purplish erythema fades to ivory white as the indurated plaques become smooth and shiny. The plaques are devoid of hairs. The induration softens as the condition resolves.

Linear morphoea is a variant in which sclerosis develops in a linear pattern. It may involve deeper underlying tissue, including the subcutaneous fat, muscle and bone. This can produce significant soft tissue deformity and result in disturbances in growth leading to permanent disfigurement. Lesions over joints produce contractures.

Generalised morphoea is a rare condition in which widespread sclerosis develops unassociated with internal manifestations.

As spontaneous resolution is the rule for most forms of localised scleroderma, adopt a policy of watchful expectancy for mild forms of the disease. For problematic lesions, use

For multiple lesions of morphoea, phototherapy may be effective.

Consider systemic therapy if the morphoea is producing debility, joint contractures, growth disturbance or severe cosmetic deformity. This arises particularly in generalised morphoea and linear morphoea. Seek specialist advice. If joint contractures are developing, physiotherapy and mobilisation are important. Treatments that are considered in severe cases include systemic corticosteroids, methotrexate, cyclosporin and acitretin.

Reconstructive surgery can be undertaken to improve deformity but this must be delayed until the morphoea is completely quiescent, because of the risk of reactivation of the disease.

Systemic sclerosis is a multisystem disease characterised by connective tissue sclerosis and atrophy and associated with vascular abnormalities. The sclerosis first affects the distal parts of the hands and feet, and the face. Raynaud’s phenomenon, sclerodactyly with pulp atrophy, calcinosis and pulp infarcts may occur. The facial skin is smooth, shiny and tight. The mouth is constricted with radial furrows.

The CREST variant (see above) is associated with a more benign course, and a lower incidence of renal involvement. Stopping smoking and ensuring that the peripheries are kept warm are useful in the treatment of Raynaud’s.

Management of systemic sclerosis should be multidisciplinary. Carefully assess and monitor internal involvement. There is no specific therapy and no treatment is proven to alter the course of the disease. Taking care of the skin is essential, and avoiding trauma and cold is paramount. As healing of minor skin trauma is often poor, give advice about appropriate wound dressings (see Wounds).

Some of the therapies used in systemic sclerosis include phototherapy, azathioprine, isotretinoin, cyclosporin, interferon gamma, and plasmapheresis combined with prednisolone and cyclophosphamide. A careful assessment of the risks and benefits of these therapies is essential, given that they are associated with variable responses and significant adverse effects.

Lichen sclerosus

Genital lichen sclerosus is discussed in Genital skin diseases.

Extragenital lesions are usually small ivory white, slightly atrophic papules that show follicular plugging and ‘cigarette paper atrophy’. Small extragenital lesions are usually asymptomatic, but if treatment is required, use

 Lichen sclerosus of the genital area

Lichen sclerosus, an uncommon and frequently misdiagnosed skin condition, has a predilection for the genital area, and is a relatively common cause of genital skin disease. It is 10 times more common in women than men. It presents as a well-defined white, finely wrinkled plaque, often with purpuric areas and ulceration. Blistering may occur. The condition is typically very itchy; however, it may occasionally be asymptomatic, or present with pain and dyspareunia due to blistering and fissuring. Any part of the external genital and perianal area may be involved, but the vagina is spared. In longstanding untreated cases, atrophy of the vulva and stenosis of the vaginal opening may occur. Lichen sclerosus affects all ages, and is associated with a tendency to autoimmune conditions such as thyroiditis. Untreated lichen sclerosus is associated with squamous cell carcinoma of the vulva in 2% to 6% of cases.

Lichen sclerosus is usually a chronic condition that may run a complicated course in which neoplasia may supervene. Management in consultation with a dermatologist is recommended.

Confirm the diagnosis by skin biopsy. This is most likely to be diagnostic if performed before any treatment is commenced, as topical corticosteroid treatment rapidly changes the typical histopathology.

Seek and treat any associated infection.

Use topical corticosteroids

Symptom control is usually achieved within the first month of therapy if a very potent corticosteroid is used initially to bring the disease under control. If cost is an issue (betamethasone dipropionate 0.05% in optimised vehicle is not on the Pharmaceutical Benefits Scheme) start with a potent topical corticosteroid, but be prepared to change to a very potent corticosteroid if treatment fails. A complete return to objective clinical normality is not usually achieved, particularly if scarring or fusion has occurred, and should not be the object of therapy. Maintenance treatment is required in most cases.

Follow-up 6-monthly for an indefinite period for carcinoma surveillance.

There is no place for vulvectomy in the management of lichen sclerosus, unless it is performed for concomitant squamous cell carcinoma of the vulva. In some cases, surgical correction of fusion and stenosis may be indicated.

For treatment of lichen sclerosus in children, see Lichen sclerosus in prepubertal girls.

 Dermatomyositis

In dermatomyositis muscle inflammation (myositis) occurs in association with a characteristic cutaneous eruption. The cutaneous lesions generally precede the onset of muscle weakness. The pathognomonic cutaneous signs are periorbital reddish purple erythema (heliotrope rash) and flat-topped papules over the dorsum of the interphalangeal joints of the hands (Gottron’s papules). Poikiloderma (skin changes of atrophy, telangiectases, hypopigmentation and hyperpigmentation) can occur, and photosensitivity is often prominent.

Although the disease has an autoimmune basis, it may be associated with an underlying malignancy (most commonly of the gastrointestinal, genitourinary or lymphoreticular systems, or of the lung or breast) in approximately a quarter of cases in adults. This malignancy can be diagnosed before, at the time of, or after the diagnosis of dermatomyositis. Drugs (eg statins) have also been implicated, although a direct causal link has not been established.

Sun exposure can exacerbate the disease; stress the need for adequate sun protection. Rest is essential when the myositis is active.

Treatment with oral corticosteroids is required in almost all cases, starting with

Reduce the dose while monitoring clinical improvement and biochemical levels (creatine kinase and creatine excretion). Severe cases may require pulse methylprednisolone.

If the disease is poorly controlled or if a corticosteroid-sparing effect is needed, add a second agent, eg azathioprine, methotrexate, cyclophosphamide, cyclosporin or IV immunoglobulin.

Treatment is often required for several years.

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