Clinical analysis on 12 cases of syphilitic optic neuritis

Abstract

Objective To explore the clinical characteristics and pathophysiological mechanism of syphilitic optic neuritis.  Methods The clinical signs and symptoms, laboratory tests, electrophysiological examinations, imaging features, treatment and prognosis of 12 cases with syphilitic optic neuritis admitted in our hospital from January 2014 to March 2016 were retrospectively analyzed.  Results The main clinical manifestation was vision loss in 12 patients (18 eyes), with acute or subacute onset, monocular attack or one after other. Degrees of visual loss differed among these patients. They also presented visual field defect and ocular fundus changes. Cerebrospinal fluid (CSF) examination showed increased white blood cell and protein. Rapid plasma reagin (RPR) assay and Treponema pallidum hemagglutination assay (TPHA) in serum were positive. RPR assay/toluidine red unheated serum test (TRUST) and TPHA in CSF were positive. Visual-evoked potential (VEP) showed prolonged latency and declined amplitude of P100 wave. MRI revealed optic atrophy, abnormal signs in medial orbital part or overall length of optic nerve. The vision was improved after intravenous injection of aqueous penicillin and muscular injection of benzathine benzylpenicillin.  Conclusions Neurosyphilis is a rare cause of optic neuritis. Differential diagnosis should be paid attention on syphilitic optic neuritis from idiopathic optic neuritis and ischemic optic neuropathy. Serologic test and CSF examination will be helpful for a clear diagnosis. Besides, early diagnosis and standard therapy are essential for vision recovery.

DOI: 10.3969/j.issn.1672-6731.2016.07.007