Kelsey Barrell

Introduction The idiopathic inflammatory myopathies (IIM) constitute a diverse group of systemic autoimmune diseases, which include various subtypes such as immune-mediated necrotizing myopathy, sporadic inclusion body myositis, polymyositis (PM), dermatomyositis (DM) (1). The estimated prevalence of PM and DM ranges from 5 to 22 per 100,000 people, while the incidence rate among individuals at risk is approximately 1.2 to 19 million per year.

Pearls POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, and skin changes) must be considered for patients with chronic inflammatory demyelinating polyradiculopathy (CIDP) not responding to corticosteroids, IV immunoglobulin (IVIg) therapy, or plasmapheresis. Thrombocytosis and polycythemia in patients with polyneuropathy should prompt further evaluation for POEMS syndrome.

Table 1. Biomarkers for Staging and Prognosis in Light Chain Amyloidosis First Author (Year) (Ref. #) (Staging System) Type Biomarkers Cutoff Values Staging Prognosis Median OS Dispenzieri et al. 2004 (6) (MAYO2004) AL NT-proBNP <332 ng/l Stage I = NT-proBNP and cTn below Stage I = 27 m cTnT <0.035 μg/l Stage II = NT-proBNP and cTn only 1 above Stage II = 11 m cTnI <0.1 μg/l Stage III = NT-proBNP and cTn above Stage III = 4 m Kumar et al.