Dermatomyositis and mucinosis

Sclerodermalike syndromes: Great imitators

Sclerodermalike syndromes (SLSs) comprise diseases with mucin deposition (eg, scleromyxedema, scleredema), with eosinophilia (eg, eosinophilic fasciitis), metabolic or biochemical abnormalities (eg, nephrogenic systemic fibrosis), or endocrine disorders (eg, POEMS syndrome, or polyneuropathy, organomegaly, endocrinopathy, monoclonal lymphoproliferative disorder, and hypothyroidism). Chronic graft-versus-host disease may also show sclerodermalike skin changes. Inherited progeria syndromes with early aging (eg, Werner syndrome) and a heterogeneous group of hereditary disorders with either skin thickening (eg, stiff skin syndrome) or atrophy and tightening (eg, acrogeria) can also imitate classic systemic sclerosis (SSc). In addition, SLSs can be provoked by several drugs, chemicals, or even physical injury (eg, trauma, vibration stress, radiation). In SLSs, the distribution of skin involvement seems to be atypical compared with SSc. The acral skin involvement is usually missing, and lack of Raynaud phenomenon, scleroderma-specific antinuclear antibodies, the absence of scleroderma capillary pattern, and internal organ manifestations indicate the presence of an SLS. Skin involvement is sometimes nodular, and the underlying tissues can also be affected. For the differential diagnosis, a skin biopsy of the deeper layers including fascia and muscle is required. Histology does not always allow differentiation between SSc and SLSs; therefore, the diagnosis is often based on the distribution, quality of cutaneous involvement, and other accompanying clinical features.

Review of Primary Cutaneous Mucinoses in Nonlupus Connective Tissue Diseases

Lichen myxedematosus is an idiopathic, cutaneous mucinosis with 2 clinicopathologic subsets. There is the generalised papular and sclerodermoid form, more properly termed scleromyxedema, and the localised papular form. We report the first case, to our knowledge, of lichen myxedematosus in association with rheumatoid arthritis as well as a case in association with dermatomyositis. An up-to-date literature review on cutaneous mucinoses and connective tissue diseases, excluding the common association of primary and secondary mucinoses with systemic lupus erythematosus, was also performed.

Diffuse cutaneous mucinosis in dermatomyositis: a case report and review of the literature

We present the case of a patient with dermatomyositis and diffuse cutaneous mucinosis and give an up-to-date detailed review of all the published cases in the English literature describing the demographics, clinical picture, pathology management, and outcomes of this unique group of patients.

Cutaneous mucinosis in mixed connective tissue disease

Cutaneous mucinosis is a group of conditions involving an accumulation of mucin or glycosaminoglycan in the skin and its annexes. It is described in some connective tissue diseases but never in association with mixed connective tissue disease. This report concerns two cases of cutaneous mucinosis in patients with mixed connective tissue disease in remission; one patient presented the papular form, and the other reticular erythematous mucinosis. These are the first cases of mucinosis described in mixed connective tissue disease. Both cases had skin lesions with no other clinical or laboratorial manifestations, with clinical response to azathioprine in one, and to an association of chloroquine and prednisone in the other.

Inverse Gottron's papules: an unusual cutaneous manifestation of juvenile dermatomyositis

Dermatomyositis is an autoimmune inflammatory myopathy characterized by unique cutaneous features. Gottron's papules are pathognomonic, lichenoid papules that can be found overlying the joints of the dorsal hand. Papules on the palms of the hand are less commonly seen, especially in the pediatric age group. Recognition of these inverse Gottron's papules as a sign of dermatomyositis is important as they may be the only cutaneous feature and may be a clue of underlying interstitial lung disease.

Identification of specific chondroitin sulfate species in cutaneous autoimmune disease

Cutaneous lupus erythematosus and dermatomyositis (DM) are chronic inflammatory diseases of the skin with accumulated dermal mucin. Earlier work has shown chondroitin sulfate (CS) accumulation within the dermis of discoid lupus erythematosus (DLE), subacute cutaneous lupus erythematosus (SCLE), and DM lesions compared with control skin. Immunohistochemistry for C4S revealed a greater density in DLE and DM lesions, whereas SCLE lesions did not differ from controls. Scleredema and scleromyxedema are attributed to increased hyaluronic acid, and lesional samples from these diseases also demonstrated accumulated dermal C4S. Interferon-γ and interleukin-1α, but not interferon-α, treatment of cultured dermal fibroblasts induced mRNA expression of CHST-11, which attaches sulfates to the 4-position of unsulfated chondroitin. These studies on possible CS core proteins revealed that serglycin, known to have C6S side chains in endothelial cells, had greater density within DM dermal endothelia but not in DLE or SCLE, following the pattern of C6S overexpression reported previously. CD44 variants expand the CS binding repertoire of the glycoprotein; CD44v7 co-localized to the distribution of C4S in DLE lesions, a finding not observed in DM, SCLE lesions, or controls. Because C4S and C6S have immunologic effects, their dysregulation in cutaneous mucinoses may contribute to the pathogenesis of these disorders.

The mucocutaneous and systemic phenotype of dermatomyositis patients with antibodies to MDA5 (CADM-140): a retrospective study

BACKGROUND

Dermatomyositis (DM) is a multisystem autoimmune disease, in which serologic evidence of immune responses to disease-specific antigenic targets is found in approximately 50% to 70% of patients. Recently, melanoma differentiation-associated gene 5 (MDA5) has been identified as a DM-specific autoantigen that appears to be targeted in patients with DM and mild or absent muscle inflammation and with an increased risk of interstitial lung disease.

OBJECTIVE

We wished to understand the role of MDA5 in DM skin inflammation by testing it to determine if a specific cutaneous phenotype is associated with MDA5 reactivity.

METHODS

We retrospectively screened plasma from 77 patients with DM in the outpatient clinics at the Stanford University Department of Dermatology in California.

RESULTS

We found that 10 (13%) patients had circulating anti-MDA5 antibodies, and had a characteristic cutaneous phenotype consisting of skin ulceration, tender palmar papules, or both. Typical areas of skin ulceration included the lateral nailfolds, Gottron papules, and elbows. Biopsy specimens of the palmar papules showed a vasculopathy characterized by vascular fibrin deposition with variable perivascular inflammation. Patients with anti-MDA5 antibodies also had an increased risk of oral pain and/or ulceration, hand swelling, arthritis/arthralgia, and diffuse hair loss. Consistent with previous reports, these patients had little or no myositis and had increased risk of interstitial lung disease.

LIMITATIONS

This study was conducted at a tertiary referral center. Multiple associations with MDA5 antibodies were tested retrospectively on a relatively small cohort of 10 anti-MDA5-positive patients.

CONCLUSION

We suggest that MDA5 reactivity in DM characterizes a patient population with severe vasculopathy.

[Dermatomyositis]

Dermatomyositis is a form of idiopathic inflammatory myopathy that involves skeletal muscle and skin. The objectives of this review are to briefly describe the cutaneous manifestations of the disease, to raise some questions still debated about amyopathic dermatomyositis, and to reflect current knowledge of an interesting aspect in dermatomyositis as it is the risk to develop malignancy. Although clear evidence for a significant dermatomyositis-cancer association exists, optimal clinical or biological factors that predict an association with cancer have not been identified. Recently, some specific autoantibodies in dermatomyositis have been shown to be associated with internal malignancy. They open up the possibility to have available serological markers for detecting cancer-associated myositis in the near future.

Lung adenocarcinoma, dermatomyositis, and Lambert-Eaton myasthenic syndrome: a rare combination

The incidence of lung neoplasms is increasing in Brazil and in the world, probably as a result of the increase in smoking. Due to the greater number of cases, atypical presentations appear. We report the case of a 66-year-old hypertensive male smoker who presented progressive proximal muscular weakness and, in two months, evolved to dysphagia, dysphonia, and V-shaped skin lesions on the chest. A chest X-ray showed a spiculated pulmonary nodule in the right upper lobe. The biochemical analysis revealed elevated creatine kinase levels. After complementary tests and biopsies, the patient underwent right upper lobectomy. Histopathology showed a moderately differentiated adenocarcinoma. The overall analysis of the case and a review of the literature allow us to suggest that the clinical profile of the patient was a result of an overlap of two paraneoplastic syndromes (dermatomyositis and Lambert-Eaton myasthenic syndrome) secondary to lung adenocarcinoma.

Dermatomiosite

Dermatomiosite é doença idiopática inflamatória crônica que afeta a musculatura estriada, a pele e outros órgãos. Apresenta critérios diagnósticos definidos por Bohan & Peter, podendo os pacientes ser classificados em cinco grupos: dermatomiosite juvenil, dermatomiosite primária idiopática, dermatomiosites amiopáticas, dermatomiosite associada a neoplasias e dermatomiosite associada a outras doenças do tecido conectivo. O sexo feminino é mais afetado, e a idade média do diagnóstico é 40 anos. Manifestações cutâneas são observadas em todos os pacientes. Das alterações sistêmicas, a manifestação muscular mais freqüente é a perda de força proximal, e a manifestação pulmonar mais comum é a pneumopatia intersticial. Podem ser observadas neoplasias durante o seguimento da doença, sendo mais freqüentes nos pacientes acima de 60 anos. A desidrogenase lática é a enzima muscular alterada na maioria dos casos. Para diagnóstico da dermatomiosite, pode ser realizado exame anatomopatológico de biópsia cutânea e biópsia muscular, além de eletroneuromiografia. Os corticóides são a terapia mais utilizada. As causas de óbito mais freqüentes são a neoplasia maligna, a septicemia e a infecção pulmonar.

Dermatomyositis

Dermatomyositis (DM) is a chronic inflammatory disorder of the skin and muscles. Although thought to be autoimmune in origin, many questions remain as to the etiopathogenesis of this disease. DM has classically been considered a humorally mediated disease. Current evidence, however, seems to increasingly support alternative (though not mutually exclusive) mechanisms of pathogenesis, including cell-mediated and innate immune system dysfunction. Pathologic findings of DM in muscle include infarcts, perifascicular atrophy, endothelial cell swelling and necrosis, vessel wall membrane attack complex deposition, and myocyte-specific MHC I upregulation. As for the skin, histopathologic findings include hyperkeratosis, epidermal basal cell vacuolar degeneration and apoptosis, increased dermal mucin deposition, and a cell-poor interface dermatitis. Autoantibodies, particularly those that bind nuclear or cytoplasmic ribonucleoprotein antigens, are also commonly found in DM, although their importance in pathogenesis remains unclear. Defective cellular clearance, genetic predilection and environmental exposures, such as viral infection, may also play an important role in the pathogenesis of DM. The seminal work regarding the pathogenesis of DM is reviewed and an update on the recent basic and molecular advances in the field is provided.

Cutaneous mucinosis associated with dermatomyositis and nephrogenic fibrosing dermopathy: fibroblast hyaluronan synthesis and the effect of patient serum

BACKGROUND

Dermal mucin is an amorphous gelatinous substance composed primarily of hyaluronan (HA) and sulphated glycosaminoglycans (GAGs). In primary cutaneous mucinosis, accumulation of mucin is a characteristic feature of lichen myxoedematosus, scleromyxoedema and reticular erythematous mucinosis. Secondary mucinoses are disorders where mucin deposition is an additional finding, and deposition is associated with lupus erythematosus, dermatomyositis, scleroderma and granuloma annulare. The underlying cause of the abnormal mucin deposition is unknown. An increasing number of cases of a fibromucinous scleromyxoedema-like disorder associated with renal dysfunction, recently termed nephrogenic fibrosing dermopathy (NFD), is being reported.

OBJECTIVES

To examine the synthesis of sulphated GAGs and HA by fibroblasts derived from uninvolved and involved skin of a patient with dermatomyositis and two patients with NFD, and the effect of patient serum.

METHODS

GAGs were quantified by a radiometric assay and HA was determined by an enzyme-linked HA-binding protein assay.

RESULTS

We found that fibroblasts derived from active lesions of NFD synthesize elevated levels of GAGs, and in particular HA, compared with normal controls, while serum from the patient with dermatomyositis and the two patients with NFD stimulates GAG synthesis, including HA synthesis, by both control and patient fibroblasts.

CONCLUSIONS

Fibroblasts from patients with active NFD are either activated to synthesize elevated levels of HA or contain another cell type, possibly derived from circulating fibrocytes. In both disorders, there is additionally a serum-derived factor that stimulates production of sulphated GAGs and HA by fibroblasts.

[Strip papular mucinosis associated with systemic sclerosis]

INTRODUCTION

Other than discreet infra-clinical mucinous deposits observed during many inflammatory dermatoses, clinically visible dermal mucinosis can sometimes be associated with collagenosis. It is usually lupus and very rarely scleroderma. In this case, no confusion with papular mucinosis must be made.

CASE REPORT

A 51 year-old woman presented with infiltrated erythematous lesions in strips on the inner sides of the thighs and legs, associated with myalgia, arthralgia and puffy fingers. Mixed connective tissue disease was the initial diagnosis. The clinical picture was rapidly completed by sclerodactylia, telangiectasia, a Raynaud's syndrome and esophageal involvement leading to the diagnosis of CREST-type systemic scleroderma. The biopsy of the erythematous strip lesions revealed a dermal mucinosis. Treatment with hydroxychloroquine led to the regression of the mucinous lesions and the stabilization of the scleroderma, which, four years later, had not developed further.

DISCUSSION

Dermal mucinosis can accompany lupus erythematosus, in rare cases dermatomyositis and, in exceptional cases, scleroderma. The clinical presentation varies with large infiltrated plaques, reticulated or papulo-nodular lesions. Conversely, strip lesions such as those observed in our patient have never been reported till now. The association of a localized dermal mucinosis and a scleroderma must not lead to the erroneous diagnosis of papular mucinosis of clearly differing prognosis. The occurrence of a mucinosis during collagenosis might be related to enhanced synthesis of mucin by the fibroblasts mediated by the inflammatory cytokines, increased in this context.

Self-healing juvenile cutaneous mucinosis

Self-healing juvenile cutaneous mucinosis is an extremely uncommon disorder characterized by the acute eruption of multiple papules and subcutaneous nodules. In this report, we describe one of the youngest patients reported to date with self-healing juvenile cutaneous mucinosis and further define several of the histologic and clinical characteristics unique to the disorder. Awareness of this disease is important because, despite an ominous presentation, all reported cases have resolved spontaneously. Therefore, aggressive therapy should be avoided.

Skin involvement in dermatomyositis

PURPOSE OF REVIEW

Dermatomyositis (DM) is a rare multisystem autoimmune disorder of adults and children that primarily affects skin and skeletal muscle. Classification systems of dermatomyositis, polymyositis, and the other idiopathic inflammatory myopathies focus primarily on features of muscle involvement. However, cutaneous disease does not always parallel muscle disease in its onset, activity, or response to therapy. This review will describe the distinct cutaneous clinical and histopathologic presentation of DM and the relation between these cutaneous findings, pathogenesis of DM, and serological subsets of DM.

RECENT FINDINGS

This review discusses recent findings that have begun to elucidate the pathogenesis of DM, including polymorphism of tumor necrosis factor-alpha 308A allele and maternal fetal microchimerism. The recent description of other systemic diseases and drugs causing DM-like eruptions and the recognition that DM can resemble other common dermatoses highlights the need for a cutaneous biopsy to diagnose and distinguish the cutaneous features of DM. Once diagnosed, a number of noninvasive imaging modalities and new cutaneous assessment instruments can be used to follow and evaluate patients with DM.

SUMMARY

Recognition of cutaneous and histopathologic findings in DM is essential for prompt and accurate diagnosis and treatment of DM.

Dermatomyositis: an overview of recent progress with emphasis on dermatologic aspects

Important points regarding DM and C-ADM are as follows: C-ADM is a working functional designation for patients having the skin-only and skin-predominant subsets of DM, amyopathic DM, and hypomyopathic DM. C-ADM seems to have approximately 10% the incidence of classic DM in whites and possibly a higher incidence in Asians. Some patients who present with C-ADM, with or without subclinical laboratory abnormalities, can slowly progress to develop symptomatic muscle weakness over a period of years, whereas others go for 10 to 20 years and longer without the appearance of muscle weakness. C-ADM patients are at risk for potentially life-threatening complications of classic DM, such as interstitial lung disease, which may occur in up to 10% of C-ADM patients. This risk seems to be even greater in some ethnic subgroups (e.g., Japanese). C-ADM patients may also be at increased risk for internal malignancy and until further studies are carried out to confirm the statistical significance of this association, all such patients should have a thorough evaluation for internal malignancy, identical to the approach currently used in classic DM patients. Dermatologists are in the best position initially to diagnose C-ADM patients and can contribute greatly to their overall management and quality of life. Ongoing vigilance is required, however, for complications that can arise in C-ADM patients including potentially fatal interstitial lung disease, internal malignancy, delayed onset of muscle weakness from myositis, and complications of systemic drug therapy. Topical therapy with broad-spectrum sunscreens, anti-inflammatories, and antipruritics should be maximized during the initial management of the cutaneous manifestations of either classic DM or C-ADM. Single-agent or combined aminoquinoline antimalarial therapy represents the safest initial form of systemic therapy for DM-specific skin disease occurring in any clinical setting; however, this approach tends to be less effective in general than for cutaneous LE. There is a theoretical rationale for and limited preliminary successful anecdotal experience with the use of anti-TNF-alpha therapy in refractory cases of classic DM and C-ADM. Cautious systematic clinical trials in this area should be considered.