Geoffrey S Baird1, Thomas J Montine. 1. Department of Pathology, University of Washington, Harborview Medical Center, Box 359645, Seattle, WA 98104-2499, USA. geoffsbaird@gmail.com
Abstract
CONTEXT: Idiopathic inflammatory myopathies (IIMs), including dermatomyositis, polymyositis, and inclusion-body myositis, can be difficult to diagnose. OBJECTIVE: To determine if a multiplex immunoassay for markers of inflammation in muscle homogenates correlates with a diagnosis of IIM. DESIGN: Frozen archived muscle biopsy specimens from 30 patients with IIM and 34 patients without IIM were homogenized and analyzed for cytokine content with a multiplex microbead-based immunoassay system. Analyte concentrations were normalized to total lysate protein concentration prior to comparison. RESULTS: Two cytokines, interleukin 1ra and monocyte chemoattractant protein 1, and 1 soluble adhesion molecule, intracellular adhesion molecule 1, were found at significantly greater concentrations in muscle samples from patients with IIM. Intracellular adhesion molecule 1 levels alone were 83% sensitive and 91% specific for IIM at a cutoff of 1240 pg/mg muscle protein. CONCLUSIONS: Immunoassays for selected inflammatory markers can serve in conjunction with histopathologic analysis as sensitive and specific tools for the diagnosis of IIM.
CONTEXT: Idiopathic inflammatory myopathies (IIMs), including dermatomyositis, polymyositis, and inclusion-body myositis, can be difficult to diagnose. OBJECTIVE: To determine if a multiplex immunoassay for markers of inflammation in muscle homogenates correlates with a diagnosis of IIM. DESIGN: Frozen archived muscle biopsy specimens from 30 patients with IIM and 34 patients without IIM were homogenized and analyzed for cytokine content with a multiplex microbead-based immunoassay system. Analyte concentrations were normalized to total lysate protein concentration prior to comparison. RESULTS: Two cytokines, interleukin 1ra and monocyte chemoattractant protein 1, and 1 soluble adhesion molecule, intracellular adhesion molecule 1, were found at significantly greater concentrations in muscle samples from patients with IIM. Intracellular adhesion molecule 1 levels alone were 83% sensitive and 91% specific for IIM at a cutoff of 1240 pg/mg muscle protein. CONCLUSIONS: Immunoassays for selected inflammatory markers can serve in conjunction with histopathologic analysis as sensitive and specific tools for the diagnosis of IIM.
Authors: Frederick G Strathmann; Grace Borlee; Donald E Born; Luis F Gonzalez-Cuyar; Bertrand R Huber; Geoffrey S Baird Journal: Clin Chem Date: 2011-12-28 Impact factor: 8.327
Authors: Jane M Fall-Dickson; Sandra A Mitchell; Susan Marden; Edward S Ramsay; Jean-Pierre Guadagnini; Tianxia Wu; Lena St John; Steven Z Pavletic Journal: Biol Blood Marrow Transplant Date: 2010-02-06 Impact factor: 5.742