[Dermatomyositis associated with hepatitis B virus-related hepatocellular carcinoma: a case report in Peru]

Dermatomyositis is an idiopathic inflammatory myopathie characterized by proximal skeletal muscle weakness, typical skin manifestations and muscle inflammation. This disease has been associated with malignancies as a paraneoplastic syndrome. We present a patient of thirty-three years diagnosed with hepatitis B, chronic inactive HBV who presents papular, pruritic and desquamative lesions on the face, hands, inguinal area and feet. At the physical examination is evidentiated Gottron's papules, heliotrope sign and proximal symmetric muscular weakness. Findings compatible with DM were found in a skin biopsy. An abdominal ultrasound revealed a liver tumor whereby a biopsy was performed and the result was a moderately differentiated hepatocellular carcinoma. Subsequently, a segmentectomy has been made and consequently the DM symptoms decreased. This case is of great interest and rare reason why we decided to reported it.

Anti-MDA-5 Dermatomyositis Presenting with Rapidly Progressive Interstitial Lung Disease: A Cautionary Tale

A 68-year-old Indian man presented with a pruritic eruption on his neck, back, elbows, knees, and the dorsum of his hands. He was initially treated for possible Lyme's disease by his primary care physician, but without improvement. Then he developed daily chills and fevers up to 101 °F, as well as shortness of breath. A chest radiograph showed patchy airspace opacities suggestive of atypical pneumonia, and the patient was treated with levofloxacin and prednisone. Although prednisone diminished the eruption, the patient continued to experience fever, malaise, and generalized weakness, at which point he was hospitalized. Blood cultures and an antinuclear antibodies (ANA) were negative and extensive lab workup was only notable for an elevated erythrocyte sedimentation rate (ESR) (63 mm/hr, Reference Range 0-22), mild transaminitis (AST 77 U/L, Reference Range 10-40), hyponatremia (131 mEq/L, Reference Range 135-145) and elevated ferritin (440, Reference Range 20-500). The patient was discharged on 20 mg of prednisone, with referral to rheumatology and dermatology for possible autoimmune diseases.

Diagnostic potential of sarcoplasmic myxovirus resistance protein A expression in subsets of dermatomyositis

AIMS

To elucidate the diagnostic value of sarcoplasmic expression of myxovirus resistance protein A (MxA) for dermatomyositis (DM) specifically analysing different DM subforms, and to test the superiority of MxA to other markers.

METHODS

Immunohistochemistry for MxA and retinoic acid-inducible gene I (RIG-I) was performed on skeletal muscle samples and compared with the item presence of perifascicular atrophy (PFA) in 57 DM patients with anti-Mi-2 (n = 6), -transcription intermediary factor 1 gamma (n = 10), -nuclear matrix protein 2 (n = 13), -melanoma differentiation-associated gene 5 (MDA5) (n = 10) or -small ubiquitin-like modifier activating enzyme (n = 1) autoantibodies and with no detectable autoantibody (n = 17). Among the patients, nine suffered from cancer and 22 were juvenile-onset type. Disease controls included antisynthetase syndrome (ASS)-associated myositis (n = 30), immune-mediated necrotizing myopathy (n = 9) and inclusion body myositis (n = 5).

RESULTS

Sarcoplasmic MxA expression featured 77% sensitivity and 100% specificity for overall DM patients, while RIG-I staining and PFA reached respectively 14% and 59% sensitivity and 100% and 86% specificity. In any subset of DM, sarcoplasmic MxA expression showed higher sensitivity than RIG-I and PFA. Some anti-MDA5 antibody-positive DM samples distinctively showed a scattered staining pattern of MxA. No ASS samples had sarcoplasmic MxA expression even though six patients had DM skin rash.

CONCLUSIONS

Sarcoplasmic MxA expression is more sensitive than PFA and RIG-I expression for a pathological diagnosis of DM, regardless of the autoantibody-related subgroup. In light of its high sensitivity and specificity, it may be considered a pathological hallmark of DM per se. Also, lack of MxA expression in ASS supports the idea that ASS is a distinct entity from DM.

Correlation between quantitative and semiquantitative magnetic resonance imaging and histopathology findings in dermatomyositis

OBJECTIVES

The aim of this study was to compare muscle biopsy findings, as well as clinical and analytical features, with those of magnetic resonance imaging (MRI) studies of muscle in patients with dermatomyositis.

METHODS

All patients from the Longitudinal Myopathy Cohort of the Hospital Clínic de Barcelona were prospectively included in the study from 2009 to 2016. MRI images of muscle and fascial oedema were compared with muscle pathology results using both quantitative and semi-quantitative scores.

RESULTS

We found a statistically significant association between the inflammatory infiltrate and both muscle (r2=0.54, p=0.001) and fascial oedema (r2=0.54, p<0.001). In addition, muscle oedema was significantly associated with punched-out vacuoles (p=0.04) and muscle enzymes in serum (r2=0.34, p=<0.01 for CK and r2=0.22, p<0.05 for aldolase). The number of treatment drugs received at the time of MRI was inversely associated with the number of muscle inflammatory cells in the biopsy and with both muscle and fascial oedema (all p<0.05).

CONCLUSIONS

Key MRI findings correlate with the main features of dermatomyositis muscle biopsy results, suggesting that MRI findings could be used as a surrogate marker of disease activity.

Clinical value of a [18F]-FDG PET-CT muscle-to-muscle SUV ratio for the diagnosis of active dermatomyositis

OBJECTIVE

To study a muscle-to-muscle standardised uptake value (SUV) ratio with FDG-PET/CT (FDG-PET) as a marker for the detection of disease activity in dermatomyositis (DM).

METHODS

Patients with DM (n = 24) who met the European Neuro-Muscular Centre diagnostic criteria were retrospectively identified over a 3-year period through a national survey. Muscle biopsy was performed in all patients. Maximum SUV was measured in proximal muscles (SUV_PROX) that had the highest radiotracer uptake on visual grading as well as in the musculus longissimus thoracis (SUV_MLT), whereas mean SUV was measured for the liver (SUV_LIV). Muscle-to-liver SUV ratios for either muscle group were compared and a SUV_PROX/SUV_MLT ratio was calculated. SUV_PROX/SUV_MLT of DM patients were compared with age- and sex-matched control subjects (n = 24) with melanoma who had received FDG-PET scans.

RESULTS

DM patients presented with proximal and symmetrical muscle uptake. Differences in SUV_PROX/SUV_LIV and SUV_MLT/SUV_LIV ratios in DM subjects were significant (p < 0.001). SUV_PROX/SUV_MLT ratios in DM and their controls also differed significantly (p = 0.0012). The SUV_PROX/SUV_MLT ratio threshold between DM subjects and controls was 1.73 with a sensitivity of 50% (CI95%, 29.1 to 70.9%) and specificity at 83.3% (CI95%, 62.6 to 95.3%). When amyopathic DM patients were removed from the analysis, specificity was increased to 95% (CI95%, 75.1 to 99.9%) with a likelihood ratio of 10 and an AUC of 83.4% (CI95%, 71.4 to 95.4%).

CONCLUSION

A muscle-to-muscle SUV_PROX/SUV_MLT ratio with a cut-off value of 1.73 in FDG-PET imaging might serve as a non-invasive marker to determine disease activity in dermatomyositis.

KEY POINTS

• [18F]-FDG PET-scanner standardised uptake value (SUV) could reflect disease activity in dermatomyositis (DM). • A ratio of SUV in proximal muscles (SUV_PROX) to SUV in musculus longissimus thoracis (SUV_MLT) could be used to determine active DM. • Active disease is suspected for SUV _PROX /SUV _MLT ratios greater than 1.73.

Serum-soluble TRAIL: a potential biomarker for disease activity in myositis patients

OBJECTIVES

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a member of the TNF super-family, which is involved in the regulation of immune response and pathogenesis of autoimmune diseases, including polymyositis (PM) and dermatomyositis (DM). In this study, we examined the level and origin of serum-soluble TRAIL (sTRAIL) in patients with PM and DM and analyzed its association with disease activity and clinical features.

METHOD

11 PM patients, 33 DM patients, and 20 healthy controls were enrolled in this study. Clinical features were recorded when admitted, and disease activity was evaluated by myositis disease activity assessment visual analogue scale (MYOACT). TRAIL expression in muscle tissues was detected by immunohistochemistry. Serum sTRAIL levels were measured by enzyme-linked immunosorbent assay. The expression of membrane TRAIL (mTRAIL) and its receptors, including DR4 and DR5, on circulating T cells was analyzed by flow cytometry.

RESULTS

TRAIL was expressed in infiltrated inflammatory cells in muscle tissues from patients. The serum sTRAIL level was markedly increased in patients and was positively correlated with the disease activity. Serum sTRAIL was decreased after therapy in patients and was specifically higher in patients with dysphagia, but lower in patients with autoantibody Jo-1 positive. The frequency of mTRAIL and its receptors on circulating T cells from patients were significantly elevated than that from healthy controls.

CONCLUSIONS

The serum sTRAIL could be a biomarker for evaluating the disease activity of PM and DM, and targeting the generation of TRAIL in T cells might be a potential approach in the treatment of PM and DM.

Disseminated Cutaneous Mycobacterium chelonae Infection in a Patient with Dermatomyositis

A 39-year-old Caucasian man with a history of dermatomyositis and diabetes mellitus on a regimen of tacrolimus and methylprednisolone presented to our dermatology outpatient clinic with a painful eruption on his left lower leg. Three months before presentation, he had been admitted to the hospital for cellulitis of the left leg. During admission, a needle aspirate of the left leg cellulitis was performed to obtain fluid for culture to guide therapy. The patient was empirically started on vancomycin 1 g every 12 hours and managed by infectious diseases. The culture yielded no growth, however, and the patient was continued on vancomycin for 2 weeks, with resolution of his cellulitis. Two months later, the patient developed multiple painful nodules on his left leg and returned to the infectious disease physician who had managed him during his inpatient stay. He was initially treated with 2 weeks of clindamycin 300 mg twice daily (bid) without improvement. This was then followed by 2 weeks of erythromycin 500 mg every 6 hours, again without improvement. At this point, he was referred to our clinic.

Dermatomyositis Developing Post Neoadjuvant Chemotherapy and Lumpectomy

Dermatomyositis is an idiopathic inflammatory myopathy known to occur as a paraneoplastic syndrome. The course of dermatomyositis is commonly reported to mirror the course of the malignancy. Here, we report a case of dermatomyositis that developed in a patient after lump- ectomy and completed chemotherapeutic treatment.

Triggers of inflammatory myopathy: insights into pathogenesis

The inflammatory myopathies, which include dermatomyositis, polymyositis, and the immune-mediated necrotizing myopathies, are a heterogeneous group of autoimmune diseases that manifest with muscle, skin, or lung damage. Collectively, these autoimmune diseases result from loss of tolerance to a select group of self-antigens, although the precise mechanism through which this occurs is not known. Infection, malignancy, and certain medications including statins and the immune checkpoint inhibitors used in cancer therapy have been identified as potential immunologic triggers of the inflammatory myopathies. Some of these triggers are classically associated with specific myositis-specific autoantibodies (MSAs). The strong association between certain triggers and MSAs provides insights into how an immunologic event can lead to loss of tolerance to specific self-antigens, resulting in autoimmune disease. In this review, we discuss the proposed triggers of the inflammatory myopathies and their associations with MSAs, and provide insights into how these triggers may result in the inflammatory myopathies.

[Dermatomyositis associated with anti-MDA5 autoantibody]

Dematomyositis is an idiopathic inflammatory myopathy with a variable clinical spectrum. In recent years, a number of myositis-specific antibodies have been identified including anti-MDA5, which is us eful for diagnosis, prognosis and classification of the diverse clinical forms of the disease. This antibody is associated with cutaneous ulcers, rapidly progressive interstitial lung disease, early mortality and poor prognosis, so the detection of this antibody in a suitable clinical context, raises the need for an aggressive immunosuppressive treatment. We describe a case of dermatomyositis classified as hypomyopathic (i.e. involving mild muscle weakness), presenting specific skin lesions, interstitial lung disease, and presence of anti-MDA5 antibody that had a favorable response to combined treatment with cyclophosphamide, gamma globulin and corticosteroids.

Panniculitis associated with amyopathic dermatomyositis

Panniculitis is a rare clinical finding in dermatomyositis, with less than 30 cases reported and there is only one case associated with the amyopathic subtype described in the literature. The present report describes a 49-year-old female patient that one year after being diagnosed with amyopathic dermatomyositis, presented indurated, painful, erythematous to violaceous nodules located on the upper limbs, thighs and gluteal region. Skin biopsy revealed lobular panniculitis with a lymphocytic infiltrate. The patient was treated with prednisone and methotrexate, but remained unresponsive to treatment.

[Spontaneous pneumomediastinum: A rare complication of dermatomyositis]

Dermatomyositis is a rare connective tissue disease of unknown origin, including inflammatory myopathy and cutaneous manifestations. Several pulmonary complications associated to dermatomyositis were described; especially interstitial lung disease. Some rare and particular pulmonary complications were reported in the literature such as pneumodiastinum and pneumothorax. We are describing here, a case report about a female patient, who presented with dermatomyositis associated to pneumomediastinum as a severe and lethal complication without pneumothorax. It is a novel observation depicting this severe and rare complication. Brutal dyspnea and cervical subcutaneous crackling are alarming signs that should make practitioners think about this complication.

Hypoxia triggers IFN-I production in muscle: Implications in dermatomyositis

Dermatomyositis is an inflammatory myopathy characterized by symmetrical proximal muscle weakness and skin changes. Muscle biopsy hallmarks include perifascicular atrophy, loss of intramuscular capillaries, perivascular and perimysial inflammation and the overexpression of IFN-inducible genes. Among them, the retinoic-acid inducible gene 1 (RIG-I) is specifically overexpressed in perifascicular areas of dermatomyositis muscle. The aim of this work was to study if RIG-I expression may be modulated by hypoxia using an in vitro approach. We identified putative hypoxia response elements (HRE) in RIG-I regulatory regions and luciferase assays confirmed that RIG-I is a new HIF-inducible gene. We observed an increase expression of RIG-I both by Real time PCR and Western blot in hypoxic conditions in human muscle cells. Cell transfection with a constitutive RIG-I expression vector increased levels of phospho-IRF-3, indicating that RIG-I promotes binding of transcription factors to the enhancer sequence of IFN. Moreover, release of IFN-β was observed in hypoxic conditions. Finally, HIF-1α overexpression was confirmed in the muscle biopsies and in some RIG-I positive perifascicular muscle fibres but not in controls. Our results indicate that hypoxia triggers the production of IFN-I in vitro, and may contribute to the pathogenesis of DM together with other inflammatory factors.

The Use of Rituximab in the Management of Refractory Dermatomyositis

There is growing adoption of rituximab in the treatment of dermatomyositis patients whose disease is refractory to steroids. However, the effects have not been extensively studied. This is a retrospective study of 25 patients with dermatomyositis who were treated with rituximab. Data from January 2000 to July 2014 was obtained from a clinical data repository, which yielded results from two tertiary centers in the United States. We analyzed information on muscle weakness, skin disease, enzyme levels, and immunosuppressive medication use before and after treatment with rituximab. The follow-up time was six months. Among the patients with skin disease before treatment with rituximab, 72.2% had a clinical improvement in their skin disease at the follow-up visit (P less than0.01). Among the patients with proximal muscle weakness before treatment with rituximab, 81.8% had clinical improvement in their symptoms at the follow-up visit (P less than0.01). The average prednisone dose before rituximab therapy was 18.9 mg, and this dropped to 11.0 mg at follow up (P less than 0.05). The average number of immunosuppressive medications taken by patients dropped from 2.04 to 1.74 (P less than0.05). These changes were less in magnitude and significance among the subset of patient that had an additional connective tissue autoimmune condition. <p><em>J Drugs Dermatol. 2017;16(2):162-166.</em></p>.

Dermatomyositis, clinically presenting with cutaneous ulcers, with histopathologic evidence of perforating collagenosis

Dermatomyositis is a systemic, autoimmune diseasewith a variety of clinical features that often includemyositis and characteristic cutaneous findings. Asubset of patients with dermatomyositis developcutaneous ulcers, often in the setting of vasculitis orvasculopathy. We present a case of dermatomyositiswith cutaneous ulcers that show perforatingcollagenosis on histopathologic examination.Acquired reactive perforating collagenosistypically occurs in the setting of diabetes mellitus,chronic renal failure, and other pruritic conditions,and this case represents a rare association withdermatomyositis, which may ultimately be helpful inelucidating the pathophysiology of this perforatingdisorder.

The Role of Electrodiagnostic Testing, Imaging, and Muscle Biopsy in the Investigation of Muscle Disease

PURPOSE OF REVIEW

This article reviews the roles of electrodiagnostic testing, imaging studies (MRI and ultrasound), and muscle biopsy in evaluating patients for possible muscle diseases.

RECENT FINDINGS

In addition to electrodiagnostic testing and muscle biopsy, muscle imaging is increasingly being used in the evaluation of patients with suspected muscle disease. MRI and ultrasound can help identify patterns of muscle involvement that may narrow the differential diagnosis and guide further testing. In addition, imaging can identify potential targets for muscle biopsy and can help evaluate for and exclude certain conditions that may mimic muscle disease.

SUMMARY

This article provides a comprehensive overview of various testing modalities used in the evaluation of patients with suspected muscle disease, including electrodiagnostic studies, muscle imaging, and biopsy. In combination with a thorough history and clinical examination, these modalities can help narrow the differential diagnosis or, in certain cases, can confirm a specific etiology of muscle disease.