An autopsy case of dermatomyositis with rapidly progressive diffuse alveolar damage

The diagnostic utility of anti-melanoma differentiation-associated gene 5 antibody testing for predicting the prognosis of Japanese patients with DM

OBJECTIVE

Interstitial lung disease (ILD), especially rapidly progressive ILD (RPILD), is a major poor prognostic factor in patients with DM. We investigated the association of anti-melanoma differentiation-associated gene 5 (MDA5) antibody (Ab) with clinical characteristics and mortality in Japanese patients with DM.

METHODS

Seventy-nine DM patients, comprising 58 classic DM and 21 clinically amyopathic DM (CADM) patients, were enrolled. Serum Abs were screened by immunoprecipitation assays, and an immunosorbent assay (ELISA) was used for MDA5. The relationships of clinical characteristics and mortality with each Ab were investigated.

RESULTS

Anti-MDA5 Ab was detected in 17 patients. Anti-clinically amyopathic DM 140  kDa polypeptide Abs (anti-CADM-140 Abs) were found in 16 of the 17 anti-MDA5 Ab(+) patients. Skin ulcers, palmar papules, CADM, RPILD and mediastinal emphysema were widely distributed in anti-MDA5 Ab(+) patients. Mortality at 6 months as well as 5 years was also significantly higher in anti-MDA5 Ab(+) patients than in anti-MDA5 Ab(-) patients. In a multivariable Cox regression analysis, mortality was independently associated with anti-MDA5 Ab (relative hazard 6.33; 95% CI 1.43, 28.0). All of the deaths in anti-MDA5 Ab(+) patients were attributed to respiratory failure of RPILD; however, RPILD did not worsen in any of the anti-MDA5 Ab(+) patients who survived the first 6 months.

CONCLUSION

The presence of anti-MDA5 Ab identifies the characteristic skin, musculoskeletal, pulmonary and prognostic features in patients with DM. In addition, anti-MDA5 Ab seems to predict a group of patients with CADM-complicated fatal RPILD.

Clinical manifestation and prognostic factor in anti-melanoma differentiation-associated gene 5 antibody-associated interstitial lung disease as a complication of dermatomyositis

OBJECTIVE

The aim of this study is to evaluate the clinical manifestation and prognostic factors of anti-melanoma differentiation-associated gene 5 (MDA5) antibody-associated interstitial lung disease (ILD) with DM.

METHODS

Fourteen patients who presented with anti-MDA5 antibody and 10 patients with anti-aminoacyl-tRNA synthetase (ARS) antibody were enrolled. All patients were diagnosed as having DM with ILD. Clinical manifestations in the patients with anti-MDA5 antibody were compared with those in the patients with anti-ARS antibody.

RESULTS

The frequencies of acute/subacute interstitial pneumonia (A/SIP) and fatal outcome were significantly higher in the subset with anti-MDA5 antibody. The creatine kinase (CK) value was significantly lower and the gamma-glutamyl transpeptidase and ferritin values were significantly higher in the subset with anti-MDA5 antibody. Significant correlations were found between PaO(2)/F(i)O(2) and ferritin (r(s) = -0.59, P = 0.035), alveolar-arterial oxygen difference (A-aDO(2)) and KL-6 (r(s) = 0.73, P = 0.016) and A-aDO(2) and ferritin (r(s) = 0.66, P = 0.013) in the subset with anti-MDA5 antibody. The most significant prognostic factor was ferritin. The cumulative survival rate was significantly lower (P < 0.0001) in the subset with ferritin >or=1600 ng/ml than that in the subset with ferritin <1600 ng/ml in anti-MDA5 antibody-associated ILD.

CONCLUSION

Both serum ferritin and anti-MDA5 antibody are powerful indicators for the early diagnosis of A/SIP with DM. Ferritin also predicts disease severity and prognosis for patients with anti-MDA5 antibody. Intensive treatment should be administered to cases that have anti-MDA5 antibody-associated ILD with DM showing hyperferritinaemia, especially if the ferritin level is >or=1600 ng/ml.

Increased ferritin predicts development and severity of acute interstitial lung disease as a complication of dermatomyositis

OBJECTIVES

Acute/subacute interstitial pneumonia (A/SIP) is an intractable and fatal complication of DM. Since a useful indicator predicting the complication of A/SIP has not been found, the aim of this study was to determine whether serum ferritin is a potential predictive indicator of the occurrence of A/SIP in 64 patients with DM.

METHODS

Of the total patients enrolled, 19 had A/SIP, 24 had chronic interstitial pneumonia and 21 were without interstitial lung disease (ILD). Clinical manifestations and laboratory data were obtained from medical records on admission.

RESULTS

Serum ferritin levels were extremely high in patients with DM with A/SIP. It was significantly higher in DM with A/SIP than that in DM without A/SIP (median 790 vs 186 ng/ml; P < 0.0001). The cumulative survival rate for 6 months was 62.7% in patients with DM with A/SIP. Moreover, the cumulative survival rate was significantly (P = 0.016) lower in the group with ferritin levels > or =1500 ng/ml than the rate in the group with ferritin levels <1500 ng/ml.

CONCLUSIONS

Serum ferritin can be useful as a predictor of the occurrence of A/SIP and correlates with the prognosis of A/SIP in DM. The intensive treatment using combination therapy with various immunosuppressant agents should be chosen for patients with ILD with DM showing hyperferritinaemia, especially levels >1500 ng/ml.

Cutaneous lesions of dermatomyositis with supervening fibrosis

BACKGROUND

Dermatomyositis (DM) is a distinctive systemic connective tissue disease whereby the skin defines a cardinal site of involvement. There exists a body of literature, which suggests that a significant component of its clinical manifestations may be related to endothelial cell injury. We have postulated in the past that anti-endothelial cell antibodies may be the defining trigger leading to endothelial cell dysfunction. The primary organs affected by DM are the skin and muscle. A significant albeit rare complication is pulmonary fibrosis, which our recent study postulated to be attributable to an autoimmune endothelialitis.

DESIGN

We describe six patients, four women and two men who ranged in age from 3 to 60 years, and had classic clinical presentations and cutaneous lesions of DM without any supervening clinical changes indicative of cutaneous sclerosis.

RESULTS

Skin biopsies showed cell-poor interface dermatitis with variable dermal mucin and C5b-9 within the cutaneous vasculature. However, at variance with classic DM was the presence of a sclerodermoid tissue reaction, which was of variable depth. All of these patients had severe muscle involvement. One pediatric patient had concomitant significant cutaneous, central nervous system and oral mucosal ischemic infarcts. Significant pulmonary disease ensued in the four adult patients, manifesting as pulmonary fibrosis in two, diffuse alveolar damage in one and diaphragmatic failure in one. In three patients, direct immunofluorescent studies were corroborative of immune-based microvascular injury while Western blot and/or indirect immunofluorescent studies showed anti-endothelial cell antibody activity within the serum of three patients.

CONCLUSIONS

The identification of sclerosis in biopsies of skin lesions typical clinically for DM may be a harbinger for more severe autoimmune-based endothelial cell injury phenomenon. One could speculate that its basis may be attributable to elevated serum levels of the natural fibrogenic factor, transforming growth factor beta, which in turn is released from damaged endothelium.

Transient elevation of the tumor markers CA 15-3 and CASA as markers of interstitial lung disease rather than underlying malignancy in dermatomyositis sine myositis

A 37-year-old woman with severe interstitial lung disease associated with dermatomyositis sine myositis is reported. A thoracoscopic lung biopsy revealed organizing diffuse alveolar damage. Significantly elevated serum levels of the tumor markers CA 15-3 and CASA (cancer-associated serum antigen) were detected, but no evidence of an underlying malignancy (including breast and ovarian) was found on serial clinical and radiologic examinations. These levels gradually normalized as the interstitial lung disease responded to a combination of cyclophosphamide and corticosteroids. The use of the CA 15-3 and CASA assays to measure serum levels of the highly glycosylated, high-molecular-weight mucin MUC1 in interstitial lung disease has not been previously described. Clinicians should therefore be aware that elevation of these tumor markers may reflect the presence of interstitial lung disease rather than an underlying malignancy in patients with dermatomyositis, especially if the levels normalize after successful treatment of the lung disease.

Fatal acute fibrinous and organizing pneumonia in a child with juvenile dermatomyositis

Acute fibrinous and organizing pneumonia, a recently described form of diffuse acute lung injury, sometimes affects adults with inflammatory myopathy. We describe a child with juvenile dermatomyositis who had development of acute fibrinous and organizing pneumonia. There does not appear to be a successful method of treatment, particularly in severe cases with respiratory failure.