It appears as a consequence of another chronic illness, which can be autoimmune (SLE, thyroiditis), inflammatory (chronic cholangitis, chronic hepatitis, syphilis, schistosomiasis), paraneoplastic when the primary site expresses PLA2R (breast, lung, gastrointestinal tract, and skin cancers, etc.), or other (sarcoidosis). This evidence concerns the gene PLA2R1 and systemic lupus erythematosus.