Abstract: 【Abstract】 Objective To analyze clinical characteristics of neurosyphilis patients with abnormal mental behaviors as the initial symptom, and to provide a reference for clinical classification of, as well as outcome prediction and efficacy monitoring in neurosyphilis. Methods Clinical data were collected from 67 HIV-negative neurosyphilis patients with abnormal mental behaviors as the initial symptom in the Second Affiliated Hospital of Soochow University from November 2012 to November 2019, and retrospectively analyzed. Statistical analysis was carried out by using t test. Results Among the 67 patients, 52 （77.6%） were males, and 15 （22.4%） were females; there were 63 （94.0%） middle-aged and elderly patients and 4（6.0%） adolescent patients; 38 （56.7%） patients were diagnosed with progressive general paresis, 21（31.3%） with meningovascular neurosyphilis, 1 （1.5%） with meningeal neurosyphilis, 3 （4.5%） with tabes dorsalis, and 4 （6.0%） with mixed-type neurosyphilis. As laboratory examination showed, 67 patients all presented with positive serum rapid plasma reagin（RPR） test, serum Treponema pallidum particle agglutination（TPPA） test, and cerebrospinal fluid TPPA test, 55 （82.1%） had positive cerebrospinal fluid RPR test, 47（70.1%） had elevated cerebrospinal fluid protein levels of > 0.45 g/L, 50 （74.6%） had increased white blood cell counts of > 8 ×106/L in cerebrospinal fluids, and 28 （41.8%） had elevated IgG levels in cerebrospinal fluids. Magnetic resonance imaging of the brain revealed multiple ischemic foci in 21 （31.3%） cases, multiple leukodystrophy in 17 （25.4%）, cerebral atrophy in 15 （22.4%）, infarction in 8 （11.9%）, and encephalitis-like changes in 2 （3.0%）. Of the 67 patients, 48 were treated with penicillin in aqueous solutions, 15 with ceftriaxone, and 4 with doxycycline. Six months later, the follow-up showed that 46 （68.7%） patients responded to the treatment, and the early course of disease was significantly shorter in the highly responsive group than in the poorly responsive group （P < 0.05）. Conclusion The middle-aged and elderly males were predominant in the neurosyphilis patients with abnormal mental behaviors as the initial symptom, magnetic resonance imaging is helpful for clinical classification and prognosis prediction of neurosyphilis, and early and standardized antisyphilitic treatment can markedly improve the prognosis of patients.

Key words: Neurosyphilis, Mental disorders, Magnetic resonance imaging, Treatment outcome