Dermatology Online Journal

Sclerodermatomyositis associated with severe arthritis
Agustí Toll MD¹, Jordi Monfort MD², Pere Benito MD², and Ramon M Pujol MD¹
Dermatology Online Journal 10 (2): 18

From the departments of Dermatology¹ and Rheumatology², Hospital del Mar. IMAS.Barcelona

---

Abstract

Overlap syndromes are a spectrum of diseases with clinical features of two or more classic connective tissue diseases. Polymyositis or dermatomyositis that is associated with features of systemic sclerosis, also called sclerodermatomyositis, is an uncommon overlap syndrome, with a rare antibody directed against the nucleolar antigen PM-Scl. This disease generally has good prognosis. We report a case of sclerodermatomyositis with an aggressive pulmonary and articular course.

---

Clinical summary

A 30-year-old woman presented with a 6-year history of Raynaud phenomenon, induration of the hands, narrowing of the nose, and facial telangiectasias (Fig. 1). She also had developed progressive interphalangeal arthritis with severe metacarpal-phalangeal ulnar deviation (Fig. 2).

Figure 1	Figure 2

She complained of recent onset of dyspnea and proximal muscle weakness. Physical examination revealed erythematous plaques over the dorsal interphalangeal and metacarpophalangeal joints (Fig. 2). The palms and soles were hyperkeratotic (Fig. 3). A skin biopsy from the dorsal aspect of the hand showed hyperkeratosis, vacuolization of the basal keratinocytes, perivascular lymphocytic infiltrate, and dermal fibrosis (Fig. 4).

Figure 3	Figure 4

The following serum muscle enzymes were increased: creatine kinase (1580 IU, normal 20-170), aspartate aminotransferase (94 IU, normal 10-38), alanine aminotransferase (47 IU, normal 7-33), lactic dehydrogenase (1098, normal 150-450), and aldolase (70 IU, normal 0-7). A deltoid muscle biopsy revealed perivascular, perifascicular inflammation and atrophy with segmental fiber necrosis. Immunological tests revealed positive antinuclear antibodies (1:2560) with a nucleolar pattern. Rheumatoid factor, and tests for anti-Scl-70, anti-centromere, anti-RNP, anti-Ro, and anti-La antibodies were within normal limits. HLA-DR typing revealed the patient to be heterozygous for HLA-DR3/4. The anti-PM-Scl antibody was demonstrated by protein immunoprecipitation. Radiographs of the hands disclosed severe acro-osteolysis. Pulmonary function tests disclosed a severe decrease of carbon-monoxide diffusion capacity, and CT scan of the thorax showed pulmonary fibrosis.

After a diagnosis of sclerodermatomyositis was established, the patient was treated with prednisolone and chloroquine, with moderate response.

Discussion

Polymyositis or dermatomyositis associated with features of systemic sclerosis, also called sclerodermatomyositis (SDM), is one of the most uncommon overlap syndromes. An antibody directed against the nucleolar antigen PM-Scl is the main biological marker of this disease. It is present in more than 50 percent of adults with this syndrome [1] and persists regardless of the activity of the illness. Anti-PM-Scl antibodies identify patients with homogeneous overlap connective tissue disease, clinically defined by Raynaud phenomenon, scleroderma, myositis, arthritis, and pulmonary restriction [2].

Cutaneous manifestations of SDM include Raynaud phenomenon and sclerodermatous involvement of the hands, present in almost all patients with this syndrome. Other cutaneous features, such as poikiloderma and Gottron sign, may also be found.

So-called machinist's hands or mechanic's hands are characterized by painful hyperkeratosis, scales, fissures, and hyperpigmentation of the fingertips along the lateral and palmar aspects of the fingers. These lesions are histologically nonspecific. Although machinist's hands have been considered to be most characteristic of patients with antisynthetase syndrome [3], they may occur in SDM [2, 4] and other connective tissue diseases [5].

About 30 percent of patients with SDM develop acro-osteolysis. Although arthritis of the small joints of the hands and feet is common (97 %), ulnar deviation of the metacarpal-phalangeal joints is not (3 %). Almost 90 percent of patients have at least one episode of myositis. Pulmonary disease is found in more than 75 percent of anti-PM-Scl-positive patients, and it usually responds favorably to moderate immunosuppression. In 75-100 percent of cases, patients with anti-PM-Scl antibodies are homozygous for HLA-DR3 or heterozygous for HLA-DR3/4 [2, 4].

In addition to dermatomyositis and scleroderma, the differential diagnosis of SDM should include antisynthetase syndrome, in which both machinist's hands and severe pulmonary involvement are frequently observed.

Patients with SDM usually run a mild course and respond favorably to nonsteroidal anti-inflammatory drugs or oral corticosteroids. However, some manifestations such as arthritis and pulmonary involvement may be severe; close followup and aggressive treatment may be warranted.

References

1. Jablonska E, Chorzelski T, Blaszczyk M, Jarzabek-Chorzelska M, Kumar V, Beutner EH. Scleroderma/polymyositis overlap syndromes and their immunologic markers. Clin Dermatol.10(4):457-72 Review,1992. PubMed

2. Marguerie C, Bunn CC, Copier J, Bernstein RM, Gilroy JM, Black CM, So AK, Walport MJ. The clinical and immunogenetic features of patients with autoantibodies to the nucleolar antigen PM-Scl. Medicine Baltimore.71:327-336,1992. PubMed

3. Plotz PH, Dalakas M, Leff RL, Love LA, Miller FW, Cronin ME. Current concepts in the idiopathic inflammatory myopathies: polymyositis, dermatomyositis, and related disorders. Ann Intern Med.Jul.5;111(2):143-57,1989. PubMed

4. Oddis CV, Okano Y, Rudert WA, Trucco M, Duquesnoy RJ, Medsger TA Jr.. Serum antibody to the nucleolar antigen PM-Scl. Arthritis Rheum.35: 1211-17,1992. PubMed

5. Stahl NI, Klippel JH, Decker JL. A cutaneous lesion associated with myositis. Ann Intern Med.Oct;91(4):577-9,1979. PubMed

© 2004 Dermatology Online Journal