Background Dermatomyositis (DM)/ polymyoitis (PM) are systemic diseases characterized by muscle inflammation, which shows varieties of clinical symptoms and signs. We have experienced cases of DM/PM with generalized edema as reported previously by others (1). Moreover, we found that there were many myositis patients who lost their body weight (BW) after starting of high dose glucocorticoid (GC) therapy. Thus, we hypothesized that hidden generalized edema is a characteristic clinical feature of myositis.
Objectives To determine whether generalized edema is a hidden clinical feature of myositis. If so, what myositis patients have the feature.
Methods The study was a retrospective observation study. The subjects were consecutive 67 of DM/PM and 53 of SLE patients who diseases for the first time, admitted our department from April 2007 to September 2016 and received immunosuppressive therapy including over 30mg/day GC. The patients were excluded who had cardiogenic or nephrogenic edema or whose BW data was not available. To detect hidden generalized edema caused by inflammation, we examined the change in BW within 2 weeks after starting immunosuppressive therapy. The clinical features of DM/PM patients with/without BW change were examined through reviewing medical record.
Results The included subjects were DM/PM 66 patients (M/F; 18/48 with a mean age of 59.4 y.) and SLE 40 patients (M/F;14/26 with a mean age of 49.8 y.). The body weight of DM/PM and SLE were 56.4±14.0 and 54.7±10.9 kg, respectively.
Decrease in BW within 2weeks after starting the therapy were 3.02±2.99kg of DM/PM and 0.85±2.87 kg of SLE, which was larger in DM/PM compared to SLE (Fig A). The numbers of patients who lost BW more than 2kg within the 2 weeks were 42 in DM/PM (64%) and 14 in SLE (35%).
Serum albumin levels were slightly decreased by 0.18 g/ dl (0.06 to 0.30; 95% CI) in DM/PM, while no significant change was detected in SLE.
In myositis, change in BW was similar among DM, amyopathic DM (ADM) and PM (Fig.B). Moreover, no differences were found in the change of BW between patients with and without male sex, malignancy, interstitial pneumonia, anti-ARS Ab and anti-MDA5Ab. Additionally, between patients with and without BW loss more than 2kg, no differences were found in age, serum TP, Alb and CRP levels before and after treatment and prognosis.
Conclusions DM/PM patients lose BW by immunosuppressive therapy including GC, which indicates the existence of hidden generalized edema that might be a characteristic clinical feature in inflammatory myopathy.
Tu J1, McLean-Tooke A, Junckerstorff R. Increasing recognition of dermatomyositis with subcutaneous edema - is this a poorer prognostic marker? Dermatol Online J. 2014;20:21244.
Disclosure of Interest None declared