TY - JOUR
T1 - Autoimmune aquaporin-4 myopathy in neuromyelitis optica spectrum
AU - Guo, Yong
AU - Lennon, Vanda A.
AU - Bogdan, Bogdan F.
AU - Grouse, Carrie Katherine
AU - Topel, Jordan
AU - Milone, Margherita
AU - Lassmann, Hans
AU - Parisi, Joseph E.
AU - Pittock, Sean J.
AU - Stefoski, Dusan
AU - Balabanov, Roumen
AU - Lucchinetti, Claudia F.
PY - 2014/8
Y1 - 2014/8
N2 - IMPORTANCE: Documentation of muscle pathology compatible with targeting of sarcolemmal aquaporin-4 (AQP4) by complement-activating IgG implies involvement of organs beyond the central nervous system in neuromyelitis optica spectrum disorders. OBSERVATIONS: We report on a 51-year-old woman who had relapsing optic neuritis, transverse myelitis, AQP4-IgG seropositivity, and recurrent myalgias with hyperCKemia. A muscle biopsy revealed scattered myofibers with internal nuclei, atrophy, and regeneration but no necrosis. Mild inflammatory exudates, in endomysial and perivascular spaces, consisted of lymphocytes, histiocytes, and scattered eosinophils. The sarcolemma exhibited loss of AQP4 and deposition of IgG and complement activation products, characteristics not seen in control biopsy samples of healthy muscle and immune-mediated myopathies. CONCLUSIONS AND RELEVANCE: Recurrent hyperCKemia accompanying AQP4-IgG seropositivity reflects targeting of skeletal muscle AQP4 by pathogenic IgG. The entity of autoimmune AQP4 myopathy extends the neuromyelitis optica spectrum beyond the central nervous system.
AB - IMPORTANCE: Documentation of muscle pathology compatible with targeting of sarcolemmal aquaporin-4 (AQP4) by complement-activating IgG implies involvement of organs beyond the central nervous system in neuromyelitis optica spectrum disorders. OBSERVATIONS: We report on a 51-year-old woman who had relapsing optic neuritis, transverse myelitis, AQP4-IgG seropositivity, and recurrent myalgias with hyperCKemia. A muscle biopsy revealed scattered myofibers with internal nuclei, atrophy, and regeneration but no necrosis. Mild inflammatory exudates, in endomysial and perivascular spaces, consisted of lymphocytes, histiocytes, and scattered eosinophils. The sarcolemma exhibited loss of AQP4 and deposition of IgG and complement activation products, characteristics not seen in control biopsy samples of healthy muscle and immune-mediated myopathies. CONCLUSIONS AND RELEVANCE: Recurrent hyperCKemia accompanying AQP4-IgG seropositivity reflects targeting of skeletal muscle AQP4 by pathogenic IgG. The entity of autoimmune AQP4 myopathy extends the neuromyelitis optica spectrum beyond the central nervous system.
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U2 - 10.1001/jamaneurol.2014.775
DO - 10.1001/jamaneurol.2014.775
M3 - Article
C2 - 24911400
AN - SCOPUS:84905967589
SN - 2168-6149
VL - 71
SP - 1025
EP - 1029
JO - JAMA neurology
JF - JAMA neurology
IS - 8
ER -