Development and external validation of a nomogram for neurosyphilis diagnosis among non-HIV patients: a cross-sectional study

BMC Neurology

Dongdong Li¹  Wenjing Ge²  Ning Chen²  Lijie Gao²  Yang Zhang²  Jiajia Bao²  Dong Zhou²  Changling Li²  Li He²  Chao Peng² 

[1] Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, People’s Republic of China;Department of Neurology, West China Hospital, Sichuan University, Chengdu, People’s Republic of China;

关键词: Neurosyphilis;    Diagnostic model;    HIV-negative patient;    Serum TRUST;    Psychiatric behaviour disorders;   

DOI  :  10.1186/s12883-021-02454-8

来源: Springer

【 摘 要 】

BackgroundThe diagnosis of neurosyphilis is challenging due to the requirement of a lumbar puncture and cerebrospinal fluid (CSF) laboratory tests. Therefore, a convenient diagnostic nomogram for neurosyphilis is warranted. This study aimed to construct diagnostic models for diagnosing neurosyphilis.MethodsThis cross-sectional study included data of two patient cohorts from Western China Hospital of Sichuan University between September 2015 and April 2021 and Shangjin Hospital between September 2019 and April 2021 as the development cohort and the external validation cohort, respectively. A diagnostic model using logistic regression analysis was constructed to readily provide the probability of diagnosis at point of care and presented as a nomogram. The clinical usefulness of the diagnostic models was assessed using a receiver operating characteristic (ROC) and Harrell concordance (Harrell C) index for discrimination and calibration plots for accuracy, which adopted bootstrap resampling 500 times.ResultsOne hundred forty-eight and 67 patients were included in the development and validation cohorts, respectively. Of those, 131 were diagnosed as having reactive neurosyphilis under the criteria of positive results in both CSF treponemal and non-treponemal tests. In the development cohort, male, psychiatric behaviour disorders, and serum toluidine red unheated serum test were selected as diagnostic indicators applying a stepwise procedure in multivariable logistic model. The model reached 80% specificity, 79% sensitivity, and 0·85 area under the curves (AUC) (95% confidence interval, 0·76–0·91). In the validation cohorts, the Harrell C index for the diagnostic possibility of reactive neurosyphilis was 0·71.ConclusionsA convenient model using gender, presence of psychiatric behaviour disorders, and serum TRUST titre was developed and validated to indicate diagnostic results in patients suspected of neurosyphilis. Checking the model value of factors on nomogram is a feasible way to assist clinicians and primary health servers in updating patients’ medical charts and making a quantitatively informed decision on neurosyphilis diagnosis.Trial registrationThis research was retrospectively registered in the Ethics committee on biomedical research, West China Hospital of Sichuan University. The research registration and committee’s reference number was 1163 in 2020 approval.

【 授权许可】

CC BY