Ab0672 renal Involvement in Patients With Dermatomyositis and Polymyositis

Abstract

BackgroundDermatomyositis (DM) and polymyositis (PM) are characterized by moderate to severe muscle weakness and inflammatory lesions in the muscle. They lead to frequent, and, in some cases, life-threatening extramuscular (lung, cardiac, neurologic, kidney) complications.ObjectivesThe aim of this study was to determine the incidence, the severity, the course and outcome of renal diseases in patients with DM or PM.MethodsWe identified 84 patients (68 female, 16 male) with the diagnosis of DM and 23 (14 female, 9 male) with PM. Diagnosis of DM and PM was based on the ENMC classification. The mean follow-up was 5,6 ± 3,8 years. Evaluation of extramuscular involvement was mainly performed in the presence of suggestive clinical signs. Autoantibodies were detected by ELISA. Acute kidney injury (AKI) was defined as an acute doubling of serum creatinine level. Chronic kidney disease (CKD) was defined if an estimated glomerular filtration rate (eGFR) <60 mL/min on at least 2 measurements 3 months apart.ResultsOf the 107 patients, 26 were found to have suffered varying degree of renal involvement. All the 26 patients (22 patients with DM and 4 with PM) had varying degree of proteinuria and haematuria. Renal involvement consisted of aKI in 8 patients and CKD in 18 patients. Among patients with aKI, 6 (75%) progressed to CKD, including 2 patients who reached end-stage renal disease (ESRD). Acute tubular necrosis with renal failure developed in 3 patients with PM and in 4 patients with DM. In descriptive analysis, male sex, cardiovascular risk factors, the severity of muscle injury, heart involvement, and initial proteinuria (>0.3 g/d) were associated with aKI. In multivariate survival analysis, only age at disease onset, male sex, history of cardiovascular events, and a previous episode of aKI were identified as risks factors of CKD. Although the proteinuria and haematuria responded to therapy (except in 2 cases), the creatinine clearance remained decreased during the treatment. Kidney biopsy was performed in 16 patients and showed chronic tubulointerstitial nephritis (7 cases), minimal change disease (2 cases), focal segmental glomerulosclerosis lesions (3 cases), IgA nephropathy (2 cases), membranous nephropathy (1 case), and amyloid deposits (1 case).ConclusionOur data clearly indicate that DM and PM are associated with a wide range of renal disorders. Renal damage was noted in 24,3% of all included patients. AKI occurred in 7,48% of cases and CKD developed in 16,82% of the patients. AKI and CKD contribute to an increased morbidity in these patients. AKI and CKD are probably not a direct manifestation of PM or DM, but rather result from drug and myoglobin-induced renal damage. However, aKI and CKD contribute to increased morbidity in these patientsDisclosure of interestsNone declared

IgM nephropathy in a patient with dermatomyositis following COVID‐19 vaccination: A case report

“…Renal involvement is uncommon in DM compared with other autoimmune disorders such as systemic lupus erythematosus (SLE), systemic scleroderma, and microscopic polyartritis 4 . Acute kidney injury, renal tubular damage associated with myoglobinemia and myoglobinuria following acute rhabdomyolysis, and, rarely, chronic glomerulonephritis are the three major renal manifestations of DM 5 …”

“…4 Acute kidney injury, renal tubular damage associated with myoglobinemia and myoglobinuria following acute rhabdomyolysis, and, rarely, chronic glomerulonephritis are the three major renal manifestations of DM. 5…”