Dermatomyositis With Panniculitis - SKINmed 2007;6(1):46-47

Sueli Carneiro, MD, PhD; Giselle Alvim, MD; Patricia Resende, MD; Maria Auxiliadora Jeunon Sousa, MD; Tullia Cuzzi, MD, PhD; Marcia Ramos-e-Silva, MD, PhD

From the Section of Dermatology, Federal University of Rio de Janeiro, School of Medicine, HUCFF; and Section of Dermatology, State University of Rio de Janeiro, School of Medicine, HUPE, Rio de Janeiro, Brazil

Case 1. A 23-year-old white housewife presented with an erythematous violaceous rash on her face, neck, chest, and limbs, particularly over the dorsum of the hands and fingers; diffuse alopecia; and an inability to climb stairs and get up from a low seat. The clinical examination showed red to violaceous well-demarcated plaques on sun-exposed areas on the dorsum of the fingers and hands, with periungual erythema and telangiectasia; facial erythema; and heliotrope rash. There was also symmetric involvement of proximal muscles of the limbs. Laboratory examination showed hypergammaglobulinemia, elevated serum aspartate aminotransferase, and serum alanine aminotransferase; normal activities of creatinokinase, lactate dehydrogenase, and aldolase; an antinuclear antibody titer of 1:40 with a speckled pattern; negative anti-DNA and anti-Scl70; and normal serum complement levels (C3, C4, and CH50). Urinalysis results were within normal limits. Skin biopsy histopathology showed hyperkeratosis, edema of the upper epidermis, scattered inflammatory infiltrate, and focal accumulation of mucin in the form of acid mucopolysaccharides. Deep asymptomatic nodules on the inner upper limbs appeared later. Histopathology of these lesions showed focal areas of lobular panniculitis in the subcutaneous tissue, with lymphoplasmocytic inflammatory infiltrate without vasculitis ( Figure 1 and Figure 2 ).

Case 2. A 29-year-old white housewife presented with an erythematous violaceous rash on her face, neck, chest, and lower extremities. Clinical examination showed red to violaceous well-demarcated aching plaques on the internal surface of the thighs and tips of the fingers; periungual erythema and digital petechiae; Raynaud’s phenomenon; and bilateral ulnar and cervical enlarged lymph nodes. Laboratory examination showed elevated serum aspartate aminotransferase, alanine aminotransferase, creatinokinase, lactate dehydrogenase, and aldolase; negative venereal disease research test results; an antinuclear antibody titer of 1:1024 with speckled pattern; negative anti-DNA and anti-Scl70; and normal serum complement levels (C3, C4, and CH50). Urinalysis results were within normal limits. Histopathology of the deep asymptomatic nodule on the inner left thigh showed lobular panniculitis with a scattered inflammatory infiltrate and diffuse fat necrosis, in addition to calcium deposition between the lipocytes and microcysts without vasculitis ( Figure 3 ).

Dermatomyositis is an acquired, chronic, inflammatory muscle disorder of unknown cause. It occurs in children and adults, producing disability caused by muscle weakness and a characteristic rash. Panniculitis is associated with an immunologic and inflammatory disease of the vessels and connective tissue that may be uncommonly seen in dermatomyositis. 1, 2 Pathologic studies and clinical observation suggest that variable degrees of subcutaneous inflammation occur in dermatomyositis, but only severe panniculitis can be clinically recognized. 1–4 Winkelman and colleagues 3 believe that the changes observed in the adipose tissue are focal and infrequent and not characteristic enough to produce a clinical syndrome of panniculitis.

This panniculitis is clinically characterized by painful, indurated, erythematous nodules with or without ulceration and sometimes with multifocal lipoatrophy. 1, 4 Histologic findings are usually characterized by dense lobular infiltration of lymphocytes, plasma cells, and histiocytes with fat necrosis and subsequent fibrosis. Calcified areas, ulceration, fistules, vasculitis, and endothelial swelling of subcutaneous and membranocystic lesions can also be observed. The pathogenesis of panniculitis in dermatomyositis is unknown. Inflammatory changes in the subcutaneous fat could be considered the first manifestation of the calcification process, but calcification is common in late dermatomyositis without preceding panniculitis. 5–7 The parallel courses of panniculitis and muscular involvement and simultaneous changes of the skin in the epidermis and subcutaneous fat in some cases suggest that they are pathogenetically related. 3

Panniculitis can precede the other changes associated with dermatomyositis by as much as 14 months, therefore it is prudent to check the muscle enzymes and follow patients regularly in cases of idiopathic panniculitis. 8 Patients with dermatomyositis who develop panniculitis exhibit a good clinical response to treatment; therefore, it has been suggested that panniculitis may be a positive prognostic sign. 9, 10

Conclusions

Panniculitis is a rare clinical presentation of dermatomyositis characterized by indurated erythematous nodules or plaques with or without ulceration. Histopathology shows dense lobular infiltrates of lymphocytes, plasma cells, and histiocytes with fat necrosis and subsequent fibrosis. Calcified areas, ulceration, fistules, and membranocystic lesions may be observed.

Panniculitis can precede the other signs of dermatomyositis by as much as 14 months.

Figure1. Focal areas of lobular panniculitis in the subcutaneous tissue with lymphoplasmocytic inflammatory infiltrate without vasculitis; hemotoxylin and eosin stain; original magnification ×100.
 

Figure2. Focal areas of lobular panniculitis in the subcutaneous tissue with lymphoplasmocytic inflammatory infiltrate without vasculitis; hemotoxylin and eosin stain; original magnification ×400.
 

Figure3. Lobular panniculitis in the subcutaneous tissue with a scattered inflammatory infiltrate and diffuse fat necrosis, in addition to calcium deposition between the lipocytes and microcysts without vasculitis; hemotoxylin and eosin stain; original magnification ×400.

References