An international consortium, including clinicians from the Institute of Myology, pooled clinical and biological data from patients suffering from a rare form of inflammatory myopathy, Ku-positive myositis, and compared them with existing data for autoimmune necrotising myopathy (AINM):
- 26 muscle biopsies (anti-Ku-positive) from a cohort of 50 Japanese patients and 10 German patients investigated for myositis were reanalysed a posteriori,
- histological features common to AINM were found,
- the researchers distinguished two distinct patterns in terms of necrosis and regeneration,
- and revealed differences (not statistically significant) in the distribution of HLA alleles in these two sub-groups.
As a result of this work, anti-Ku positive myositis appears to be relatively heterogeneous.