Purpose
Necrotising autoimmune myositis (NAM) or immune mediated necrotising myopathy (IMNM) is a group of recently recognised inflammatory myopathies defined by distinct clinical, histological and serological features (1, 2). Despite of growing experiences over the past decade, optimal strategies to manage this group of disorders is still lacking, despite a global effort and previous consensus statements (3). The purpose of this study is to examine clinical and treatment variables and their effects on clinical outcomes, in the hope to add to the growing literature of IMNM management.
Methods
This is a retrospective study. At John Hunter Hospital, specimens were sent to one of the two centres (SA pathology and RPAH) with specific interest in muscle pathology. Histology reports were reviewed to identify cases that fulfill the histological criteria of IMNM. Then serological data on these cases were reviewed, including myositis specific antibody status. Clinical data including initial serum creatine kinase, muscle strength, patient demographics and treatment within one month of diagnosis will be collected. Primary outcome is defined as muscle strength at 6 months.
Logistic regression analyses will be performed to identify clinical and biochemical predictors of primary outcome. Given the consideration that initial treatment within one month of diagnosis may be influenced by initial clinical presentation, interactions of covariates will be checked. Given the rarity of these disease, it is anticipated that additional cases from other centres will also need to be included.
Results and Conclusions
TBA