Treatments for Syphilis: Penicillin G and Linezolid

Abstract

Syphilis is a common sexual disease that is transported by body fluid and caused by a spirochete bacterium Treponema pallidum. With the development of antibiotics that are applied to treating syphilis, the number of patients suffering from syphilis has decreased rapidly since 1943, when penicillin antibiotics were started to be introduced as clinical pharmaceuticals to treat syphilis. However, in recent years, the number of patients of syphilis has increased again, 95% of the patients are infected by sexual intercourse. The World Health Organization (WHO) reported that in 2022, nearly 8 million adults who are between 15 and 49 years old acquired syphilis. Because most infections are asymptomatic and unrecognizable during the long incubation period, many people are unconscious of syphilis infection, and they do thus not go to hospitals to check whether they are infected. Penicillin G is a traditional and commonly used antibiotic to treat syphilis by inhibition of production of the complete peptidoglycan cell wall, T.pallidum cells thus burst and die due to osmotic pressure in a hypotonic environment. But penicillin G has been approved for nearly one hundred years to treat syphilis and other diseases bacteria, including T.pallidum has developed the antibiotic-resistance to penicillin G by producing β-lactamase to inactivate penicillin G by opening its β-lactam ring irreversibly. As a result, it is quite urgent and necessary to introduce a new antibiotic to confront syphilis. In 2021, scientific experiments revealed that linezolid, which has been used to treat other Gram-positive bacterial infections for a long time, has impressive effects on treatment for syphilis, indicating that this artificially developed antibiotic could be used clinically to control syphilis by blocking bacterial protein synthesis. In this paper, the symptoms of syphilis and the treatment for syphilis, including penicillin G and linezolid, will be briefly introduced.