The prevalence of asymptomatic neurosyphilis among HIV-negative serofast patients in China: A meta-analysis

Abstract

Introduction Neurosyphilis can occur at any stage of syphilis. After treatment, 30%-40% of syphilis patients remained serofast. But the prevalence of asymptomatic neurosyphilis (ANS) among serofast syphilis patients remains unclear. Untimely treatment or improper management for ANS may result in neurological complications. So we perform the meta-analysis to evaluate the prevalence of ANS cases among HIV-negative serofast syphilis patients for exploring their relationship and addressing their clinical management. Methods We searched CNKI, Wan Fang, VIP, CBMdisc, PubMed, Embase and Medline from January 1 st 1990 to September 22 nd 2020 for both English and Chinese records. We strictly restrict the eligibility criteria. STROBE was used for reporting quality assessment. We examined forest plots and conducted both fix-effects and random-effects to estimate prevalence by R version 3.6.2/R studio 1.2.1335 statistical software packages META version 4.9–9. If appropriate, between-study heterogeneity was examined using the I 2 statistic and subgroup analysis. Results Of 77 screened records, 5 were included. The pooled prevalence of ANS among HIV-negative serofast syphilis patients was 13% (95% CI 3%-23%; I 2 = 93% P<0.01, 417 people). The prevalence of ANS for the verified ANS classification definition was 3% (95% CI 0%-7%; I 2 = 67% P = 0.08, two studies, 189 people), and 21% (95% CI 6%-36%; I 2 = 86% P<0.01, three studies, 228 people) for the likely ANS classification. The prevalence of ANS among the serofast syphilis patients who were followed up for one year was 29% (95% CI 22%-36%; I 2 = 0% P = 0.5, two studies, 167 people) and 5% (95% CI 0%-13%; I 2 = 79% P = 0.03, two studies, 144 people) for two years. The prevalence in the studies from different geographical subgroups was as follows: 9% (95% CI 0%-19%; I 2 = 82% P<0.01, three studies, 169 people) in South-central China, 6% (95% CI 1%-10%; one study, 106 people) in East China, and 30% (95% CI 23%-38%; one study, 142 people) in North China. Conclusion This meta-analysis showed a high estimated prevalence of ANS in HIV-negative serofast syphilis patients, the prevalence of ANS among patients diagnosed with the verified ANS case definition is much lower than that for the likely ANS classification. It may be necessary to carry out nontreponemal test, protein test and leukocyte count for cerebrospinal fluid (CSF) in treated serofast patients for better clinical management to avoid neurological complications. The case classification definition of ANS is a key factor to evaluate the prevalence. Geographical heterogeneity needs more studies to detect. In future we need better-design studies to explore relationship between ANS and s...

An Updated Review of Recent Advances in Neurosyphilis

“…Male, MSM, advanced age (≥45 years), PLWH without combined antiretroviral therapy, drug use disorder, lack of antisyphilitic therapy, reinfection after a previous syphilis infection, and patients in serofast state are risk factors for neurosyphilis, especially the late forms (8)(9)(10)(11). Elevated serum and cerebrospinal fluid (CSF) rapid plasma reagin (RPR) titer, CSF protein concentration, and increased burden of the cerebral small vessel diseases may indicate the aggravation of neurological symptoms (10,12,13). Specific subtypes of T. pallidum are more likely to induce neurosyphilis; for instance, subtype 14d is the most common neurosyphilisrelated genotype in China (14).…”

Advances in laboratory diagnostic methods for cerebrospinal fluid testing for neurosyphilis

“…Studies have shown that T. pallidum can disseminate to the central nervous system of rabbits within hours to days after inoculation ( 1 ). In recent years, with the increasing prevalence of syphilis around the world, the incidence of neurosyphilis has also increased markedly each year ( 2 ).…”

Impact of Asymptomatic Neurosyphilis on Patients Quality of Life and Social Stigma

“…In 2018, 36 cases of syphilis per 100,000 people were reported in China. 1,2 Syphilis, also called the "great imitator", can have various symptoms, making diagnosis difficult. 3,4 Syphilis is treated with antibiotics; 5 however, if it is not treated on time and the Treponema pallidum invades the nervous system, it leads to neurosyphilis.…”

“…3,4 Syphilis is treated with antibiotics; 5 however, if it is not treated on time and the Treponema pallidum invades the nervous system, it leads to neurosyphilis. 1,2 Neurosyphilis usually occurs about 10 to 20 years after being first infected with syphilis. 5 It can be classified according to whether symptoms are present as symptomatic or asymptomatic.…”

“…4 On the other hand, they can be categorized as patients with mental problems because if patients with ANS are late-diagnosed or not well treated, 4 they can develop symptomatic neurosyphilis, which makes them susceptible to mental illness. 1,2,12,13 Also, it has been reported that when patients feel stigma, it will affect the treatment and prognosis of the disease due to less cooperation and social maladaptation, bringing a double burden to physical and psychological health. 14 In recent years, there have been many research reports on patients' stigma.…”