Scleromyxedema, a therapeutic dilemma.

Scleromyxedema is characterized by indurated erythematous papules disseminated on the face, chest and limbs. About twenty cases treated with thalidomide, stem cells, melphalan and immunoglobulin with varying results have been described. We present the case of a 28-year-old male patient diagnosed with scleromyxedema not associated with monoclonal gammopathy, multi-treated with anti-leprosy drugs, UVA1, and thalidomide for 4 years with no improvement.

What was known?

Scleromyxedema is a rare disease with no standard treatment. Patients die due to systemic symptoms or even from chemotherapy.

Introduction

Scleromyxedema is a generalized rare papular mucinosis (also known as lichen myxedematosus) associated to a monoclonal gammopathy and systemic symptoms.[1] Our case is an atypical scleromyxedema because the patient does not have the last two characteristics. There are about 250 cases reported in all of its modalities and no reports about this disease have emerged from our dermatology department in Mexico. Due to the extreme rarity of the disease, treatment is very difficult and most patients end up disabled or dead.

Case Report

The patient is a 28-year-old Mexican male with no previous medical history who presents a disseminated pruritic dermatosis of the face and extremities characterized by confluent erythematous papules and nodules on the face and ears causing a leonine facies [Figure 1a]. He has had an 18-month evolution during which the lesions have increased in number and size. He was treated for one year for multibacillary leprosy with WHO multidrug therapy (WHO-MDT), which includes 12 months of treatment with rifampicin 600 mg monthly + clofazimine 300 mg once a month and 50 mg daily + dapsone 100 mg daily.[2] The patient had no sign of improvement.

Figure 1

a) Symmetric generalized dermatosis with uncountable millimetric brown papules; b) Central papule associated with epidermal hyperplasia; note the abundance of mucin stained with alcian Blue (4x) and fibroblastic proliferation.

Laboratory studies, such as complete blood count, blood chemistry, liver function and thyroid function tests, HIV testing, and serum protein electrophoresis, were normal or negative.

Biopsy revealed irregular proliferation of fibroblasts associated with abundant mucin deposition in the papillary dermis establishing the diagnosis of atypical scleromyxedema not associated with monoclonal gammopathy [Figure 1b]. Due to an error by pathology, the patient was diagnosed and treated as leprosy, with the absence of systemic disease and completely normal laboratory tests, including monoclonal gammopathy being notable.

The patient was treated unsuccessfully with hydroxychloroquine 200 mg/day for four months, plus 21 sessions of UVA1 at doses of 10-40 J/cm2 followed by thalidomide 50-100 mg/day for 3 months.

Discussion

Scleromyxedema is a chronic rare skin disease of unknown etiology that affects middle-aged adults. It manifests as a generalized symmetric eruption of 2-3 mm firm waxy papules in a linear pattern that converge in indurated plates on the extremities, upper trunk, glabella, neck and ears, sometimes mimicking the leonine facies of leprosy, a finding similar to that of our patient. It never affects the mucous membranes or the scalp.[1345]

There may be erythema, edema, hyperpigmentation and itching, and in advanced stages, thickening of the skin with sclerodactyly, and decreased mobility of the mouth and joints, which causes severe disability. Skin biopsy shows fibroblast proliferation, and increased collagen and mucine.[13] It is associated with a monoclonal gammopathy (IgG λ). Extracutaneous manifestations include cardiovascular, gastrointestinal, pulmonary, rheumatologic, and neurologic signs and symptoms.[156]

Multiple drugs have been used without success; however, there are recent reports of cases successfully treated with intravenous immunoglobulin, thalidomide, melphalan, bortezomib, and autologous stem cell transplantation Table 1].

Table 1

A few case reports with successful treatment

The use of thalidomide (100 mg/day) for one year in scleromyxedema has been reported to improve mobility and the skin.[7] Bortezomib and melphalan associated with autologous stem cell transplantation, thalidomide or dexamethasone have also been reported with good results.[8] The use of immunoglobulin has been satisfactory, more so in cases of papular mucinosis and recently there is a case in combination with lenalidomide.[910] On occasion, the increase in monoclonal antibodies disappears with treatment, but this is not related to its symptomatology.[1]

Conclusion

Scleromyxedema is a chronic and systemic disease without no specific treatment. Our review describes improvement of this condition with different treatment regimens. Thalidomide, melphalan and IVIG remain the best choices to treat this unpredictable disease.

Because of the rarity of this disease, and treatment failure in most cases, long-term surveillance is needed to verify the effectiveness of the treatment provided

What is new?

This is the first case reported in Mexico. This presentation is an atypical form without systemic symptoms and monoclonal gammopathy. Treatment was unsuccessful with thalidomide