The Study Of AQP4Antibody And Short-term Prognosis Of Patients With First-ever Acute Myelitis

Objectives: Acute myelitis (AM) is an etiologically heterogeneoussyndrome with acute or subacute onset, in which inflammation of the spinalcord results in neurologic deficits, manifesting as weakness, sensory loss andautonomic dysfunction. Independent of etiology, acute myelitis prognosis ishighly variable and unpredictable. In this study, we aimed at evaluating thefrequency of AQP4antibody in patients with first-ever AM, and comparingthe clinical findings and outcome in different groups of acute myelitis forimproving the diagnosis and treatment of acute myelitis.Methods:.A consecutive series of first-ever AM cases were selected fromthe patients admitted to the third hospital of HeBei Medical Universitybetween January,2008and December,2001for a final diagnosis of AM,demyelinating disease of spinal cord, recurrent myelitis,clinically isolatedsyndrome, multiple sclerosis(MS), neuromyelitis optica (NMO).Based on theclinical and magnetic resonance imaging (MRI) findings, AM patients wereclassified as having acute complete transverse myelitis (ACTM) or acutepartial transverse myelitis (APTM), and longitudinally extensive transversemyelitis (LETM) or non-longitudinally extensive transverse myelitis(nLETM). The clinical data including age at onset, gender, diseaseduration,frequency of relapses, laboratory and MRI findings, presence of infections,clinical manifestations and therapy, expanded disability status scale (EDSS)scores at the time of maximal disability reached and final follow-up visit werereviewed retrospectively. Clinical, laboratory, and radiological features werecompared and analyzed among the subgroups.Results: Forty-eight cases met diagnostic criteria for first-ever AM.There were36women and12men(ratio3:1) with the mean age of onset was42.08±14.59years (range,12-73years). The mean length of individual spinal lesions was4.02±2.06segments on T2-weighted sagittal MRI scans, and theC3-C4was the most frequent localization of the lesions. The mean EDSSscore was4.98±2.20at the time of maximal deficit, and29%patients hadmild,29%moderate and42%severe impairment. At the end of the mean40-month of follow-up,28(58%) of patients did not show a second episode;15(31%) suffered recurrent myelitis;4(8%) developed NMO;1(2%) convertedto MS.The mean EDSS score at final follow-up was3.28±2.14,andmild,moderate and severe disability were65%,25%and10%respectively,there was a significant different compared to that at the peak of maximaldeficit(p=0.000). APTM was statistically more frequent in RTM than in themonophasic AM(P<0.05);LETM had higher EDSS scores at the time ofmaximal disability reached and final follow-up visit compared to nLETM;LETM was more frequent and EDSS scores were higher in ACTM than inAPTM; AQP4antibody was detected in48%patients with NMO,40%patients with RAM,25.0%patients with monophasic AM. Comparison withseronegative patients with AM, seropositive patients had a significantly higherpositive rate of serum antinuclear antibody and EDSS scores at final follow-upvisit. Significant differences were found in age of onset, anaual relapserate,and EDSS scores at final follow-up visit between seropositive andseronegative patients with RAM. Seropositive patients with LETM had asignificantly higher age of onset and positive rate of serum antinuclearantibody than seronegative patients.No significant differences were found inannual relapse rate, and EDSS scores between seropositive and seronegativepatients with NMO.Conclusions: Our study showed that40%of first-ever acute myelitis inthe north of China develops relapses within40months after initial AM attack.Recurrent myelitis and NMO were most frequent, and MS was the rarest. CSFpleocytosis was present in only14%of patients.2/3patients had goodoutcome. The classification of APTM/ACTM and LETM/nLETM may behelpful to predicting the prognosis of first-ever acute myelitis. Detection ofAQP4antibody can not predict relapse in patients of acute myelitis, however, AQP4antibody is a prognostic factor associated with relapse and short-timeoutcome in the patients with recurrent myelitis.