Objective To observe serum uric acid (UA) level of patients with optic neuritis (ON). Methods Thirty-nine patients with ON (ON group), 53 healthy control subjects (control group), 69 patients with multiple sclerosis (MS group) and 51 patients with neuromyelitis optica (NMO group) matched in age and sex were enrolled in the study. In ON group, there were 25 patients with papillitis and 14 patients with retrobulbar type ON. Twenty-eight patients were first time onset while 11 patients were recurrent. The disease duration was less than a year for 28 patients, and over a year for the remainder. Venous blood samples were collected from all individuals in the morning after an overnight fast. UA concentration was measured by the urate oxidaseindirect peroxidase couple assay. Differences of UA concentration were comparatively analyzed among all the groups. UA levels between different genders, different groups, different lesion sites, recurrence and duration of ON were comparatively analyzed. Results Serum UA level in ON group was significantly lower than that in control group (t=3.16,P＜0.05). However, no significant differences were found between ON and MS, ON and NMO, MS and NMO group (t=0.26, 0.94, 1.36;P＞0.05). Serum UA level was significantly lower in female than in male in all groups (F=6.27, 16.20, 21.09, 11.96;P＜0.05). In male and female patients of ON group, UA levels were significantly lower when compared with same gender in control group(t=2.13, 3.04;P＜0.05). However, no differences (P＞0.05) were found between ON and MS of same gender (t=0.25, 0.59), ON and NMO of same gender (t=0.33, 0.63), MS and NMO of same gender (t=0.63, 1.41). Patients with recurrent ON had lower serum UA level than that with first episodes (F=2.73). Patients with duration of over a year had lower serum UA level than that with duration of less than a year (F=0.23). Patients with retrobulbar neuritis also had lower serum UA level than that with papillitis (F=0.76). But the differences were not significant (P＞0.05). Conclusions A reduced serum UA level is found in patients with ON compared with healthy control. But serum UA level is not correlated with recurrence, lesion site or duration of disease.
Objective To explore underlying causes of presumptive optic neuritis (ON) in children. Methods Retrospective study of continuous cases with presumed diagnosis of optic neuritis in childhood. Results 104 cases(65.8%) met ON criteria in this cohort of children, among wh ich 80 cases (76.9%) were considered as idiopathic demyelinating optic neuritis (IDON). Infectious optic neuritis and inflammatory optic neuropathy were found on 3 cases respectively. The cause of 18 cases remains unknown. Leber hereditary optic neuropathy and non-organic visual acuity loss account most of the 54 case s misdiagnosed as optic neuritis. Conclusions As in adult patients, idiopathic demyelinating optic neuritis is the most common pathogeny of optic neuritis in children, while infectious events were more common in children. Leber hereditary optic neuropathy and nonorganic visual acuity loss were the most common disease confused with optic neuritis in childhood. Some rare disease in childhood which can cause optic nerve lesion should also be considered. (Chin J Ocul Fundus Dis, 2008,24：95-98)
Optic neuritis (ON) is one of the symptom of a central nervous system demyelinating, systemic or infectious disease. The pathogenetic mechanism of ON is still not completely clear, and its core is inflammation and immune that occurred in the optic nerve axons, and apoptosis of RGC was induced. Few patients experience recurrent episodes after treatment, presenting a remission - recurrence course of polyphasic disease, named recurrent ON (RON). Two forms of RON have been assigned: recurrent isolated optic neuritis, which is a chronic corticosteroid-dependent optic neuropathy with intermittent acute relapses, and recurrent isolated optic neuritis, which is a non-progressive relapsing ON without steroid dependence. Recurrence of ON causes cumulative damage to the optic nerve lesions and impaired visual signal transmission, thus causing irreversible damage to vision. Therefore, it is very important to have a deep understanding of the pathogenesis of ON and the clinical characteristics of RON, so as to better conduct clinical treatment.