Autoimmune inflammatory meningoencephalitis in a patient negative for glial fibrillary acidic protein-specific immunoglobulin G.

BACKGROUND: In this study, we describe clinical findings in a patient with autoimmune inflammatory meningoencephalitis who was negative for antibodies against glial fibrillary acidic protein (GFAP-IgG). METHODS: Serum and cerebral spinal fluid (CSF) samples were collected from the patient as part of a study of 520 patients with neurological syndromes. Antibodies against GFAP and other proteins associated with neurological disorders were measured by rat brain- and cell-based indirect immunofluorescence assays. RESULTS: A 42-year-old female was diagnosed with autoimmune inflammatory meningoencephalitis. She experienced a subacute and relapsing course with decreased vision, fever, headache, ataxia, hemiplegia, and disturbance of consciousness. Brain magnetic resonance imaging showed extensive lesions in the white matter along the ventricle, brainstem, right internal capsule, and meninges. The patient responded well to steroid treatment. Examination of CSF revealed a normal white blood cell count and protein level. Serum and CSF were negative for GFAP-specific antibodies and all other autoantibodies tested. Immunohistochemical staining of a brain biopsy collected during relapse revealed chronic inflammation and severe edema. Extensive and strong staining of CD163+ macrophages were evident throughout the lesions; however, CD3+ cells were rare and CD138+ and CD20+ cells were absent. CONCLUSION: We describe a case of subacute corticosteroid-responsive nonvasculitic autoimmune inflammatory meningoencephalitis in the absence of GFAP-IgG. The pathological features were distinct from those of patients with GFAP-IgG-positive meningoencephalitis, suggesting that nonvasculitic autoimmune inflammatory meningoencephalitis is a heterogeneous neurological syndrome.

Lesions of the posterior limb of the internal capsule in neuromyelitis optica spectrum disorder.

Posterior limb of the internal capsule lesions (PLICL) are one of the MRI features of neuromyelitis optica spectrum disorder (NMOSD). However, there is no evidence that such lesions are pathogenically related to NMOSD. We retrospectively analyzed features of PLICL in NMOSD, and other central nervous system inflammatory disorders, in 561 patients. We also examined the pathological samples of six patients. Of the 561 patients investigated, PLICL were found in 65 patients (11.6%). Lesions were bilateral in 26 cases (40%) and unilateral in 39 cases (60%). Unilateral lesions were mainly located on the left side (74.3%, 29/39). Of the 65 patients with PLICL, 46 patients had NMOSD (70.8%) and were positive for anti-aquaporin (AQP4-IgG), four had NMOSD (6.2%) and were AQP4-IgG negative, 10 patients had multiple sclerosis (MS), three patients had NMDAR encephalitis, and two had autoimmune meningoencephalitis. Of the six patients whose pathological samples were evaluated, all had PLICL and were negative for AQP4-IgG, and none had pathological NMOSD lesion features. These cases included three patients with multiple sclerosis, one with anti-N-methyl-D-aspartate receptor encephalitis, and two with autoimmune meningoencephalitis. In conclusion, PLICL are found not only in patients with NMOSD, but also in MS and other disorders.

Different Phenotypes at Onset in Neuromyelitis Optica Spectrum Disorder Patients with Aquaporin-4 Autoimmunity.

BACKGROUND: Although rare, brain abnormalities without optic neuritis (ON) or transverse myelitis (TM) diagnosed with neuromyelitis optica spectrum disorder (NMOSD) have been reported in patients positive for the aquaporin-4 (AQP4) antibody. OBJECTIVE: To analyze demographic and clinical differences among NMOSD patients without ON or TM, those with either ON or TM, and patients with simultaneous ON and TM at disease onset. METHODS: In this retrospective study, patients who were positive for the AQP4 antibody, as detected using a cell-based assay, at the Second Affiliated Hospital of Guangzhou Medical University in China were recruited. Demographic and clinical data were obtained from each patient's medical record. RESULTS: A total of 292 patients were included in this study and were divided into four subgroups based on their initial manifestations: (i) NMOSD without ON or TM (NMOSD-ON-TM-, n = 70); (ii) NMOSD with ON (NMOSD-ON+, n = 95); (iii) NMOSD with TM (NMOSD-TM+, n = 116); and (iv) simultaneous ON and TM [neuromyelitis optica (NMO), n = 11]. We found that age at onset was lower in the NMOSD-ON-TM- group than that in the other groups. The interval from the first episode to relapse was shorter in the NMOSD-ON-TM- group than that in NMOSD-TM+ group. Cerebral spinal fluid white cell counts and protein levels were significantly higher in the NMOSD-ON-TM- group than those in the other groups. Lower Expanded Disability Status Scale scores were observed in the NMOSD-ON-TM- group. Brain abnormalities, including in area postrema and hemisphere lesions, were more frequent in the NMOSD-ON-TM- group. Kaplan-Meier analysis showed that patients in the NMOSD-ON-TM- group experienced earlier relapse than those in other groups. Conversion to NMO in the NMOSD-ON+ group was greater than that in the other groups. Only 14 patients (4.8%, 14/292) had pure brain abnormalities, of which 12 had disease duration of several more years and 8 (57.1%) experienced relapses. CONCLUSION: NMOSD patients with different initial manifestations present with significant differences in clinical features during follow-up. Patients with long-term AQP4 autoimmunity in the brain in the absence of ON or TM are not common.

Aquaporin-4 antibody in neuromyelitis optica: re-testing study in a large population from China.

BACKGROUND: Aquaporin-4 (AQP4) antibody sero-positivity is critically important in neuromyelitis optica (NMO). However, the sensitivity of different assays is highly variable. Repeating detection with a highly sensitive assay in a large population is necessary in the case of so-called negative NMO. METHODS: Retrospective analysis where AQP4 antibodies were detected by commercial cell-based assay (CBA), in-house M23-CBA and in-house M1-CBA. RESULTS: Of the 1011 serum samples, 206 (20.4%) were sero-positive by primary commercial CBA. In the retest, all 206 participants positive by primary commercial CBA also yielded positive results by in-house M23-CBA and the second commercial CBA again, but only 124 positive in in-house M1-CBA. Among the 805 participants negative by primary commercial CBA, 71 participants were positive for in-house M23-CBA, of which 20 participants were positive for the second commercial CBA, and none were positive by in-house M1-CBA. Of the 171 cerebral spinal fluid samples, 75 (43.9%) were positive by primary commercial CBA. All 75 participants positive by primary commercial CBA also yielded positive results by in-house M23-CBA and the second commercial CBA. Forty-nine (65.3%) of these 75 participants were positive by in-house M1-CBA. Among the 96 participants negative by primary commercial CBA, 15 participants were positive for in-house M23-CBA and none were positive by in-house M1-CBA and the second commercial CBA. CONCLUSIONS: Different AQP4 isoforms in CBA result in different detection effects, and in-house M23-CBA is the most sensitive method. Some AQP4 antibody-negative NMO may be subject to diagnostic uncertainty due to limitations of the assays.

Hypothalamic abnormality in patients with inflammatory demyelinating disorders.

BACKGROUND: Hypothalamic lesions in neuromyelitis optica (NMO) patients might be more specific for NMO than multiple sclerosis (MS). However, this is controversial. OBJECTIVE: To characterize clinical features of patients with inflammatory demyelinating disorders (IDDs) with visible hypothalamic lesions using magnetic resonance imaging (MRI). METHODS: Patients with IDDs (n = 429) were recruited retrospectively. RESULTS: Of 52 patients with hypothalamic images enrolled, 42 were positive for aquaporin-4 (AQP4) antibodies, including 28 patients with NMO, 6 with recurrent transverse myelitis, 3 with recurrent optic neuritis, and 5 with brainstem and brain syndrome. The remaining 10 patients were anti-AQP4-negative, including 3 with MS, 3 with acute disseminated encephalomyelitis, and 4 with other disorders. In the AQP4-positive group, manifestations, including ataxia, intractable hiccup and nausea, syndrome of inappropriate antidiuretic hormone secretion and encephalopathy were more frequent in those with hypothalamic lesions than those without. Cell counts of cerebrospinal fluid in patients with hypothalamic lesions differed from patients without lesions. Brain MRI abnormalities were more frequent in brainstem and hemisphere of the hypothalamic lesion group. CONCLUSIONS: Hypothalamic lesions were observed frequently in patients with AQP4 antibodies. Clinical manifestations and paraclinical features in AQP4-positive patients with hypothalamic lesions differed from those without lesions.

Neuromyelitis optica spectrum disorders may be misdiagnosed as Wernicke's encephalopathy.

PURPOSE: To raise doctors' attention to the differential diagnosis of neuromyelitis optica spectrum disorders (NMOSD) and Wernicke's encephalopathy (WE). PATIENTS AND METHODS: We extensively reviewed the medical records of 136 patients who had visited our hospital since 2008 and were suspected of having central nervous system demyelinating diseases. Four of those patients had somnolence, electrolyte imbalance and brain lesions around the third ventricle and were included in the study. We tested the serum of the four patients for the presence of aquaporin-4 (AQP4) M23 antibody. RESULTS: All the four patients had positive AQP4 antibody in their serum. Two of the patients were misdiagnosed as WE before AQP4 antibody detection occurred. CONCLUSIONS: NMOSD and WE have similar brain lesion locations, histopathological changes and clinical manifestations. It is important to distinguish NMOSD from WE by detecting AQP4 antibody in serum or cerebral spinal fluid. Vitamin B1 should also be administered to the patients who have a history of thiamine deficiency.

Anti-KIR4.1 Antibodies in Chinese Patients with Central Nervous System Inflammatory Demyelinating Disorders.

OBJECTIVES: The aim of this study was to explore the frequency of KIR4.1 antibodies in patients with multiple sclerosis (MS) and in control groups using a cell-based assay. MATERIALS AND METHODS: A transfected HEK-293A cell line expressing KIR4.1 was established to test for the presence of KIR4.1 antibodies in blood serum. We tested 904 subjects, including 188 patients with MS, 264 patients with neuromyelitis optica spectrum disorders (NMOSD), 209 patients with other inflammatory neurologic disease (OIND), 203 patients with other noninflammatory neurological disease (OND), and 40 healthy controls. RESULTS: KIR4.1 antibodies were present in 23 of the 188 (12.2%) MS patients, 42 of the 264 (15.9%) NMOSD patients, 32 of the 209 (15.3%) OIND patients, 24 of the 203 (11.8%) OND patients, and 2 of the 40 (5%) healthy controls. There were no significant differences among the MS and control groups (p = 0.279). CONCLUSIONS: Anti-KIR4.1 antibody, as determined by a cell-based assay, is not a specific biomarker for MS.

Clinical manifestations of neuromyelitis optica in male and female patients.

Neuromyelitis optica (NMO) is a severe, idiopathic, immuno-mediated, inflammatory demyelinating disease of the central nervous system. We examined the clinical features between male and female NMO patients, for which not much data exist. One hundred and eight Chinese Han patients with NMO were analysed retrospectively, all had been detected for the aquaporin-4 (AQP4) antibody using a cell-based assay. Of 108 NMO patients, 92 were female and 16 were male (female/male = 5.75). Ninety-four (87%) were positive for the AQP4 antibody in their serum and/or cerebral spinal fluid. Aquaporin-4 antibody-positive NMO patients had a higher female/male ratio than the negative group (P = 0.001). Female NMO patients had a higher positive rate of the AQP4 antibody than male NMO patients (92.4 vs 56.3%, P = 0.001). All NMO male patients were divided according to their AQP4 antibody status. 77.8% (7/9) of patients in the seropositive group had initial optic neuritis, while only one patient (14.3%, 1/7) in the negative group had optic neuritis (P = 0.041). Limb paraesthesia was reported in only one patient in the negative group (11.1%), but it was reported in all patients in the positive group (100%) (P = 0.001). The mean length of vertebral segments of the spinal cord lesions was 3.6 ± 1.3 in the positive group, while it was 6.6 ± 2.6 in the negative group (P < 0.0001). The involvement of the cervical spinal cord was found in 88.9% (8/9) of the positive members, but only 11.1% in the negative group (P = 0.009). However, the involvement of the thoracic spinal cord was found in 22.2% of patients in the positive group and 85.7% of patients in the negative members (P = 0.041). In conclusion, male NMO is rare and has a low positive rate of AQP4 antibody.

No Overlap among Serum GAD65, NMDAR and AQP4 Antibodies in Patients with Neuromyelitis Optica Spectrum Disorders.

OBJECTIVE: To evaluate whether serum glutamic acid decarboxylase (GAD), N-methyl-D-aspartate-receptor (NMDAR), and aquaporin-4 (AQP4) autoantibodies coexist in patients with neuromyelitis optica (NMO)/NMO spectrum disorders (NMOSD). METHODS: Serum samples were collected from 98 patients with NMO/NMOSD. Serum GAD65, NMDAR and AQP4 antibodies were measured using a cell-based assay. RESULTS: A total of 63 patients (64.3%) had myelitis and optic neuritis and satisfied the revised diagnostic criteria for NMO. Longitudinally extensive transverse myelitis was seen on spinal cord magnetic resonance imaging, showing continuous T2-weighted signal abnormalities in at least three vertebral segments in 26 patients (26.5%); 5 patients (5.1%) had recurrent optic neuritis, and 4 patients (4.1%) had brain syndromes with optic neuritis and myelitis. None of the 98 patients had diabetes, stiff-man syndrome, or epilepsy. All 98 patients tested positive for AQP4 antibody. No patients tested positive for GAD65 and NMDAR antibodies. CONCLUSIONS: In the present study, we found no simultaneous presence of serum GAD65, NMDAR and AQP4 antibodies in patients with NMO/NMOSD.