Dermatomyositis panniculitis: a clinicopathological and immunohistochemical study of 18 cases

A case of anti-SAE1/2 antibody-positive dermatomyositis with extensive panniculitis: A possible cutaneous manifestation of treatment resistance

Dermatomyositis constitutes a heterogeneous group of autoimmune inflammatory conditions with a wide variety of clinical outcomes. The symptomatic heterogeneity carries skin, muscle, and joint manifestations; pulmonary and cardiac involvements; and concomitant malignancy. Any of these symptoms often appear at different combinations and time courses, thus posing difficulty in early diagnosis and appropriate treatment choice. Recent progress in laboratory investigations explored the identification of several myositis-specific autoantibodies (MSAs) and myositis-associated autoantibodies, allowing precise characterization for a clinical perspective of the disease. MSAs can be detectable in approximately 80% of patients with whole dermatomyositis, some of which closely reflect unique clinical features in the particular disease subset(s), including the distribution and severity of organ involvement, treatment response, and prognosis. However, only limited evidence has been available in dermatomyositis-associated panniculitis, mostly that in anti- melanoma differentiation-associated protein 5 antibody-positive disease. We present a rare case of a patients with dermatomyositis with extensive panniculitis on the trunk whose serum IgG autoantibodies reacted with both subunits of small ubiquitin-like modifier activating enzymes (SAEs), SAE1 and SAE2. The onset of panniculitis coincided with increased disease activity, including disease-related skin manifestations, fever, dysphagia, and muscle weakness in the extremities. These symptoms responded well to a high dose of systemic steroid, but even upon receiving a high-dose intravenous immunoglobulin, the panniculitic lesions and pruritic erythema flared with tapering of steroid dose, further requiring tacrolimus and mycophenolate mofetil to achieve disease remission. To our knowledge, this is the third reported case of anti-SAE autoantibody-positive dermatomyositis with panniculitis. We aim to extend the understanding of the current limitation and further perspective in the clinical management of the extremely rare skin manifestation associated with dermatomyositis.

[Increasing dyspnoea and intermittent joint suffering]

In rheumatic diseases the possibility of pulmonary manifestation must always be considered and checked. Interstitial lung disease can often be fatal in these cases. In the presented case, the link between progressive dyspnea and newly occurring skin irritation is to be seen as particularly important. A good outcome can be achieved by immediate therapy with immunosuppression and plasmapheresis.

The role of eosinophils in the differential diagnosis of inflammatory skin diseases

Eosinophils are known to be present in inflammatory skin diseases, but their diagnostic utility is not well established. Upon review of the published status of lesional eosinophils, several categories were identified. 1) Lesional eosinophils highly characteristic such that, in their absence, the pathologist may question the diagnosis. These include arthropod bite reactions and scabies, urticarial dermatitis, and other eosinophilic dermatoses. 2) Lesional eosinophils rare or absent, such that, in their presence, the pathologist may question the diagnosis. These include pityriasis lichenoides, graft versus host disease, and connective tissue disorders. 3) Lesional eosinophils variable and, while in some cases expected, are not required for diagnosis. These include drug reactions, atopic dermatitis and allergic contact dermatitis. 4) Lesional eosinophils variable and not expected but may be seen to a limited extent. These include lichen planus and psoriasis.

Subcutaneous tissue involvement in idiopathic inflammatory myopathies: Systematic literature review including three new cases and hypothetical mechanisms

INTRODUCTION

Involvement of subcutaneous tissue in idiopathic inflammatory myopathies (IIM) is poorly known.

METHODS

We conducted a systematic review of the literature regarding panniculitis and lipodystrophy/lipoatrophy in juvenile and adult IIM via PubMed/Medline, Embase and Scopus databases. Three local observations are included in this review. Epidemiological, clinical, paraclinical and therapeutic data were collected.

RESULTS

Panniculitis appears to be more common in adults than in juveniles. It was mainly localised in the upper and lower limbs. Panniculitis improved in most cases with steroids and panniculitis and myositis had a similar course in 83.3% and 72.2% of cases in juveniles and adults, respectively. Lipodystrophy appeared to be more frequent in juveniles and was only observed in dermatomyositis in both juveniles and adults. Lipodystrophy was mainly partial in juveniles and adults. The median time from myositis to the diagnosis of lipodystrophy was 6 years [0-35] and 2.5 years [0-10] in juveniles and adults, respectively. Lipodystrophy was associated with anti-TIF1 gamma auto-antibody positivity, a polycyclic/chronic course of myositis and the occurrence of calcinosis and might be an indicator of poor disease control.

CONCLUSION

Adipose tissue involvement, particularly lipodystrophy, occurs almost exclusively in dermatomyositis. The insidious onset and lack of awareness of the diagnosis may underestimate its prevalence. Larger studies are needed to identify possible risk factors in these patients, to better potential underlying pathophysiological process, in order to discuss potential therapeutic targets.

A rare case of suspected lupus erythematous panniculitis as the presenting skin feature of juvenile dermatomyositis: A case report

Juvenile dermatomyositis is a rare autoimmune myopathy of childhood, associated with systemic vasculopathy, primarily affecting the capillaries. Panniculitis is seen histologically in about 10% of patients with dermatomyositis; however, its clinical presentation is rare, with only 30 cases presented in the literature to date. The histopathology overlaps with other inflammatory disease states, and is almost identical to the panniculitis seen in lupus erythematous panniculitis. In the cases with both panniculitis and dermatomyositis, skin and muscle inflammation is usually the first clinical manifestation. We present a case of a 16-year-old female with panniculitis as the initial presenting feature of juvenile dermatomyositis in the context of a prior diagnosis of indeterminate colitis.

Subcutaneous calcinosis: Is it different between systemic sclerosis and dermatomyositis?

Calcinosis cutis is the deposition of insoluble calcium in the skin and subcutaneous tissues. It is a manifestation of several autoimmune connective tissue diseases, most frequently with systemic sclerosis and juvenile dermatomyositis, followed by adult dermatomyositis. Autoimmune connective tissue disease-associated calcinosis is of the dystrophic subtype, which occurs at sites of damaged tissue in the setting of normal serum calcium and phosphate levels. In juvenile dermatomyositis, calcinosis is considered a marker of ongoing disease activity and possibly inadequate treatment, while in adult dermatomyositis, it is a hallmark of skin damage due to chronic rather than active disease. Calcinosis is associated with long disease duration in systemic sclerosis and dermatomyositis, anti-polymyositis/sclerosis autoantibodies in systemic sclerosis and NXP-2 and melanoma differentiation-associated gene 5 in dermatomyositis. Calcinosis in systemic sclerosis occurs most frequently in the hands, particularly the fingers, whereas in dermatomyositis, it affects mainly the trunk and extremities. The primary mineral component of calcinosis is hydroxyapatite in systemic sclerosis and carbonate apatite in dermatomyositis. Calcinosis in dermatomyositis and systemic sclerosis share some pathogenic mechanisms, but vascular hypoxia seems to play a more important role in systemic sclerosis, whereas the release of calcium from mitochondria in muscle cells damaged by myopathy may be a primary mechanism contributing to dermatomyositis-related calcinosis. Multiple treatment strategies for dermatomyositis and systemic sclerosis-related calcinosis have been used with variable results. Early aggressive treatment of underlying myositis in patients with dermatomyositis may improve long-term outcomes of calcinosis. A better understanding of the pathogenesis of calcinosis is needed to improve treatment options.

High-Frequency Ultrasound to Assess Activity in Connective Tissue Panniculitis

Determining disease activity from clinical signs in patients with connective tissue panniculitis (CTP) is often challenging but is essential for therapeutic decision making, which largely relies on immunosuppressant treatment. High-frequency ultrasound (HFUS) may be useful in supporting such decisions by accurately determining CTP activity. This study aimed to investigate the accuracy of HFUS in identifying signs of CTP activity or inactivity and assess its usefulness in therapeutic decision making. A prospective cohort study of consecutive patients with biopsy-proven CTP receiving HFUS was conducted in a tertiary university hospital (2016-2020). HFUS was performed at inclusion and at each 3- or 6-month follow-up visit, depending on disease activity. Twenty-three patients with CTP were included, and 134 HFUSs were performed. In 59.7% (80) of the evaluations, the clinical presentation did not show whether CTP was active or not. In these cases, HFUS showed activity in 38.7% (31) and inactivity in 61.3% (49). In 71.25% (57) of the visits, HFUS was the determinant for therapeutic decisions. Further follow-up showed consistent clinical and HFUS responses in all unclear cases after treatment modification. HFUS appears to be a useful adjunct to the clinical examination for CTP to assess activity and make therapeutic decisions.

Painless Panniculitis upon the Treatment of Clinically Amyopathic Dermatomyositis with Anti-MDA5 Antibody

Panniculitis, a rare cutaneous manifestation in patients with dermatomyositis (DM), usually presents as a painful erythematous lesion. We herein report a 32-year-old woman with panniculitis that appeared as an indurated plaque without pain or redness after a 4-month episode of clinically amyopathic DM during treatment with prednisolone and tacrolimus. She experienced no pain; however, the firmness and extent gradually worsened. Based on our findings, including the histopathological results, DM panniculitis was diagnosed. Azathioprine was additionally administered, leading to remission. DM panniculitis can develop as a painless induration during immunosuppressive treatment, and azathioprine may be a useful treatment.

The chameleon rash: a review of the polyphenotypic dermatoses of dermatomyositis

Dermatomyositis (DM) is an autoimmune connective tissue disease that is included in the idiopathic inflammatory myopathies. Cutaneous manifestations are a prominent part of the condition: some skin signs in DM are common to most patients, while other signs are encountered infrequently. A number of features are pathognomic for DM. The demonstration of myositis-specific antibodies (MSAs) in DM has extended the ability to define phenotypic subgroups. It appears that the presence of certain MSAs confers susceptibility to specific clinical features, an association which reveals a serotype-phenotype relationship. In this review article we have provided a detailed summary of common and under-recognized cutaneous manifestations of DM.

Connective Tissue Diseases in the Skin: Emerging Concepts and Updates on Molecular and Immune Drivers of Disease

Cutaneous manifestations are common across the spectrum of autoimmune diseases. Connective tissue diseases manifesting in the skin are often difficult to classify and require integration of clinical, histopathologic, and serologic findings. This review focuses on the current understanding of the molecular and immune drivers involved in the pathogenesis of cutaneous lupus erythematosus, dermatomyositis, scleroderma/systemic sclerosis, and mixed connective tissue disease. Recent research advances have led to the emergence of new ancillary tools and useful diagnostic clues of which dermatopathologists should be aware to improve diagnostic accuracy for these diseases.

Covert clues: the non-hallmark cutaneous manifestations of dermatomyositis

Dermatomyositis (DM) is a strikingly heterogenous disease characterized by a broad and ever-evolving spectrum of cutaneous manifestations that transcend the classic “hallmarks” defined by Peter and Bohan in 1975. Despite the increasing preponderance and ubiquity of autoantibody, radiologic, and electrophysiologic testing, the diagnosis of DM still hinges largely on prompt detection of cutaneous manifestations of this condition. While pathognomonic cutaneous features of DM are more readily recognizable, many patients present with subtle and/or atypical skin manifestations, and diagnosis of DM may require clinician identification of these cutaneous clues. In this review, we highlight several of the lesser-known skin manifestations of DM, specifically, panniculitis, diffuse subcutaneous edema, erythroderma, calcinosis, ulceration, flagellate erythema, Wong-type DM, gingival telangiectasias, and the ovoid palatal patch. We describe the clinical and histopathologic presentation of these cutaneous findings. While manifesting less frequently than the heliotrope rash, Gottron’s papules, and Gottron’s sign, these cutaneous clues are equally important for clinicians to recognize in order to facilitate timely diagnosis and early intervention.

Polymyositis with antisynthetase syndrome presented with lobular panniculitis: A case report

Panniculitis is rarely seen in polymyositis. To the best of our knowledge, we report the first case of panniculitis which precedes the antisynthetase syndrome.