A 63-year-old woman presents to the dermatology clinic with an enlarging scar-like area behind her ear. The area has grown progressively over 2 years and has become increasingly tight, uncomfortable and pruritic. The area is hard, raised and erythematous with central scarring and atrophy. Her medical history is significant only for hypertension and osteoarthritis.
- What is the most likely diagnosis?
- What are the potential complications of this disease?
- What are the treatment options?
i. Based on this patient’s clinical presentation, the most likely diagnosis is morphea, an inflammatory disease in the dermis and subcutaneous structures. The main variants include plaque-type, linear and generalized morphea.
The most common variant is plaque-type morphea, which is characterized by the development of erythematous to violaceous plaques that expand radially over several years with central sclerosis. The lesions are usually asymptomatic, but more advanced lesions can cause discomfort and skin tightness owing to the progressive scarring and induration of the skin. Although these lesions usually resolve spontaneously over a course of years, they can lead to permanent atrophy and changes in pigmentation. Relapsing disease is uncommon in plaque type morphea.
Linear morphea is a clinical variant that often presents as a linear, inflammatory streak or an initial plaque-type lesion that extends longitudinally to form a scar band. One specific type of linear morphea is known as morphea en coup de sabre, which refers to linear morphea of the forehead and scalp. Generalized morphea is a rare clinical variant that occurs when multiple plaque-type lesions arise at once and become confluent to involve almost all of the total body skin surface area.
ii. Morphea is a disease process that is localized to the skin and does not involve internal organs. However, in the linear morphea variant, the underlying fascia, muscle and bone can be involved, leading to impairment of mobility. High-risk areas are those overlying the joints, which can lead to joint immobility. Morphea en coup de sabre can also involve underlying muscles and osseous structures and rarely progress to involve the eye, meninges, or brain. In the generalized form, the diffuse sclerosis can lead to vasoconstriction leading to symptoms such as difficulty breathing as a result of impaired thorax mobility and inflammation ofthe intercostal muscles.
iii. Although typical plaque-type morphea regresses spontaneously over several years, there are several treatment options available to expedite resolution. Phototherapy with UVA1 or bath PUVA therapy is efficacious in providing faster clinical improvement and longer periods of remission. For systemic treatments, immunosuppression with oral corticosteroids or methotrexate can be helpful during the acute inflammatory stages. There is some evidence supporting the efficacy of oral vitamin A derivatives such as etretinate or acitretin. Topical therapy plays a smaller role in the treatment of morphea. High-potency topical steroids, calcineurin inhibitors and vitamin D derivatives may help reduce local inflammation in acute lesions, but overall are ineffective by themselves in resolving the lesions.