Objectives: Dihydrolipoamide S-acetyltransferase (DLAT), the E2 component of the mitochondrial pyruvate dehydrogenase complex (PDC-E2), has recently been suggested to be a biomarker of chronic inflammatory demyelinating polyneuropathy (CIDP). It was particularly associated with sensory variants of CIDP. Antimitochondrial antibodies are important for the diagnosis of primary biliary cholangitis, but insofar, only 2 studies have reported an association with CIDP. Here, we aimed to validate these observations in a cohort of French patients with immune-mediated neuropathy.
Methods: The positivity against PDC-E2/DLAT was examined using ELISA and confirmed using commercially available immuno-DOT and by indirect immunofluorescence on stomach, kidney, and liver sections.
Results: None of the 20 healthy controls, 31 patients with Guillain-Barré syndrome, 102 patients with CIDP (including 24 patients with sensory CIDP), 26 patients with monoclonal gammopathy, 23 patients with Charcot-Marie-Tooth disease, or 20 patients with autoimmune nodopathy showed IgG against PDC-E2/DLAT.
Discussion: PDC-E2/DLAT is accurately a target antigen in immune-mediated neuropathies.