OBJECTIVETo assess the seroprevalence and diagnostic value of aquaporin-4 antibody (AQP4-Ab) in patients with inflammatory central nervous system demyelinating diseases.

METHODSSeventy-two patients with neuromyelitis optica (NMO), 68 with multiple sclerosis (MS), 4 with optic neuritis (ON), and 41 with transverse myelitis (TM) were included in this study. The TM group comprised 19 patients with non-longitudinally extensive transverse myelitis (nLETM), 14 with monophasic longitudinally extensive transverse myelitis (mLETM), and 8 with recurrent longitudinally extensive transverse myelitis (rLETM). The serum levels of AQP4-Ab was detected by indirect immunofluorence assay in these patients.

RESULTSAQP4-Ab was detected in 72.2% (52/72) patients with NMO, 5.9% (4/68) patients with MS, 25.0% (1/4) patients with ON, and 17.1% (7/41) patients with TM, showing a significant difference in the positivity between NMO and MS groups (P<0.01). AQP4-Ab seropositivity rate was 5.3% (1/19) in nLETM patients, 62.5% (5/8) in rLETM patients and 7.1% (1/14) in mLETM patients, significantly higher in rLETM than in nLETM (P<0.01) and mLETM groups (P<0.05), but no statistical difference was found between rLETM and NMO groups.

CONCLUSIONSA high seroprevalence of AQP4-Ab is observed in patients with NMO and rLETM, which support the hypothesis that NMO and rLETM belong to NMO spectrum disorders. AQP4-Ab can serve as a useful index for diagnosing NMO and differential diagnosis from MS. More attention and effective immunosuppressive treatments should be given to patients positive for AQP4-Ab.

Aquaporin 4 ; immunology ; Autoantibodies ; blood ; Demyelinating Autoimmune Diseases, CNS ; diagnosis ; immunology ; Female ; Humans ; Male ; Multiple Sclerosis ; diagnosis ; immunology ; Neuromyelitis Optica ; diagnosis ; immunology ; Seroepidemiologic Studies

OBJECTIVETo analyze the magnetic resonance imaging (MRI) characteristics of neuromyelitis optica (NMO) in Chinese patients.

METHODSWe retrospectively reviewed the MRI films of 61 patients with NMO (including 57 female and 4 male patients) admitted in our department.

RESULTSOf these patients, 39 (79.6%) showed positivity for serum aquaporin-4 (AQP4) antibody. On MRI, 18 patients showed involvement of the cervical cord alone, 27 had both cervical and thoracic segment involvement, and 16 displayed thoracic segment involvement. The lesions appeared linear (9 cases), diffuse (23 cases), or both (29 cases), mostly located axially with occasional lateral distribution. Thirty-nine of the 61 patients (63.9%) had brain abnormalities, 31 presented with supratentorial lesions (mostly in the juxtacortical, subcortical, deep white matter and lateral ventricle-adjacent regions, n=27), 15 showed infratentorial lesions (mostly in the preiaqueduct-fourth ventricular-central canal, n=13), and 7 had supra- and infratentorial lesions simultaneously.

CONCLUSIONNMO has complex MRI presentation, and linear lesions in the spinal cord and preiaqueduct-fourth ventricular-central canal lesions, where AQP4 is high expressed, can be characteristic for NMO. MRI and AQP4 antibody detection are suggested for suspected cases for early diagnosis.

Adult ; Aquaporin 4 ; immunology ; Brain ; pathology ; Female ; Humans ; Magnetic Resonance Imaging ; Male ; Neuromyelitis Optica ; pathology ; Retrospective Studies ; Spinal Cord ; pathology

BACKGROUND: The presence of antibodies to aquaporin-4 (AQP4) has been identified as a key characteristic of neuromyelitis optica spectrum disorder (NMOSD), an autoimmune inflammatory demyelinating central nervous system (CNS) disorder. We evaluated the performance of a cell-based indirect immunofluorescence assay (CIIFA) for detecting AQP4 antibodies using antigen prepared with a recombinant AQP4 peptide transfection technique and assessed the usefulness of CIIFA for diagnosis of NMOSD in routine clinical practice. METHODS: Forty-six serum samples from 36 patients as a comparison set and another 101 patients enrolled consecutively from a neurology clinic were included. CIIFA and fluorescence immunoprecipitation assays (FIPA) were performed. CIIFA was performed at 2 different institutions for comparison purposes. RESULTS: CIIFA and FIPA sensitivity in the comparison set was 86% and 79% in neuromyelitis optica (NMO) patients and 55% and 36% in high-risk NMO patients, respectively. The semiquantitative titer measured by CIIFA correlated well with the arbitrary unit (fluorescence units [FU]) derived from FIPA (r=0.66). Titers measured by CIIFA and FIPA were elevated in NMO patients compared to high-risk NMO patients (1:240 vs. 1:180 and 8,390 vs. 4,059 FU, respectively). The frequency of AQP4 antibody detection by CIIFA in 101 consecutively enrolled patients was 100% in NMO and 23% in high-risk NMO patients, while only 4.6% in control patients, including those with multiple sclerosis. CONCLUSIONS: Detection of AQP4 antibodies by CIIFA provides sensitive and highly specific diagnostic information for NMO and high-risk NMO patients, which can be used to differentiate these conditions from other demyelinating CNS diseases.
Adult ; Aged ; Antibodies/*blood ; Aquaporin 4/*immunology ; Female ; *Fluorescent Antibody Technique, Indirect ; Humans ; Male ; Middle Aged ; Neuromyelitis Optica/*diagnosis ; Reagent Kits, Diagnostic

BACKGROUND: The presence of antibodies to aquaporin-4 (AQP4) has been identified as a key characteristic of neuromyelitis optica spectrum disorder (NMOSD), an autoimmune inflammatory demyelinating central nervous system (CNS) disorder. We evaluated the performance of a cell-based indirect immunofluorescence assay (CIIFA) for detecting AQP4 antibodies using antigen prepared with a recombinant AQP4 peptide transfection technique and assessed the usefulness of CIIFA for diagnosis of NMOSD in routine clinical practice. METHODS: Forty-six serum samples from 36 patients as a comparison set and another 101 patients enrolled consecutively from a neurology clinic were included. CIIFA and fluorescence immunoprecipitation assays (FIPA) were performed. CIIFA was performed at 2 different institutions for comparison purposes. RESULTS: CIIFA and FIPA sensitivity in the comparison set was 86% and 79% in neuromyelitis optica (NMO) patients and 55% and 36% in high-risk NMO patients, respectively. The semiquantitative titer measured by CIIFA correlated well with the arbitrary unit (fluorescence units [FU]) derived from FIPA (r=0.66). Titers measured by CIIFA and FIPA were elevated in NMO patients compared to high-risk NMO patients (1:240 vs. 1:180 and 8,390 vs. 4,059 FU, respectively). The frequency of AQP4 antibody detection by CIIFA in 101 consecutively enrolled patients was 100% in NMO and 23% in high-risk NMO patients, while only 4.6% in control patients, including those with multiple sclerosis. CONCLUSIONS: Detection of AQP4 antibodies by CIIFA provides sensitive and highly specific diagnostic information for NMO and high-risk NMO patients, which can be used to differentiate these conditions from other demyelinating CNS diseases.
Adult ; Aged ; Antibodies/*blood ; Aquaporin 4/*immunology ; Female ; *Fluorescent Antibody Technique, Indirect ; Humans ; Male ; Middle Aged ; Neuromyelitis Optica/*diagnosis ; Reagent Kits, Diagnostic

A 53-year-old male patient presented with hypopsia of his right eye for 2 months and lower extremities weakness for 8 days. Thoracic MRI demonstrated a lesion at T3 level appearing as hyperintense on T2-weighted images with non-enhancement by contrast medium and demyelinating lesion was considered. Aquaporin-4-Ab was positive and the antibody titer was 1:320 in serum. The diagnosis of neuromyelitis optica spectrum disorders was made. In addition, systemic lupus erythematosus and thymoma coexisted in this patient. After methylprednisolone impact treatment, plasma exchange and immunosuppressive therapy, the right vision and lower extremities weakness of the patient were improved.
Anti-Inflammatory Agents ; therapeutic use ; Antibodies ; blood ; Aquaporin 4 ; immunology ; Humans ; Lupus Erythematosus, Systemic ; complications ; Male ; Methylprednisolone ; therapeutic use ; Middle Aged ; Neuromyelitis Optica ; complications ; diagnostic imaging ; drug therapy ; Thymoma ; complications ; Treatment Outcome