Using cytokine expression to distinguish between active and treated syphilis: promising but not yet ready for prime time

Distinguishing between previously treated and active syphilis can be challenging in the subset of treated patients with serofast status, defined as persistent non-treponemal seropositivity (<4-fold decline in rapid plasma reagin titre ≥6 months after treatment). The study investigated whether serum cytokine expression levels, measured with a 62-cytokine multiplex bead-based ELISA, can help guide clinical management. Using samples from patients with active, treated and serofast syphilis, the authors developed a two-cytokine (brain-derived neurotrophic factor and tumour necrosis factor β) decision tree that showed good accuracy (82%) and sensitivity (100%) but moderate specificity (45%). While further studies will be needed to confirm and refine the diagnostic algorithm, there also remain important technical, operational and financial barriers to implementing such cytokine assays in routine care.

Kojima N, Siebert JC, Maecker H, et al. The application of cytokine expression assays to differentiate active from previously treated syphilis. J Infect Dis. 2020 [published online ahead of print, 2020 Mar 19].

Global and regional prevalence of herpes simplex virus type 2 infection: updated estimates for people aged 15–49 years

Estimates of genital herpes simplex virus (HSV) infections across regions inform advocacy and resource planning and guide the development of improved control measures, including vaccines. In 2016, HSV-2 affected 13% of the global population aged 15–49 years (high-risk groups …