Chlamydia treatment failure after repeat courses of azithromycin and doxycycline

Therapeutic Options for Chlamydia trachomatis Infection: Present and Future

Sexually transmitted infections (STIs), such as Chlamydia trachomatis (Ct) infection, have serious consequences for sexual and reproductive health worldwide. Ct is one of the most common sexually transmitted bacterial infections in the world, with approximately 129 million new cases per year. C. trachomatis is an obligate intracellular Gram-negative bacterium. The infection is usually asymptomatic, notwithstanding, it could also be associated with severe sequels and complications, such as chronic pain, infertility, and gynecologic cancers, and thus there is an urgent need to adequately treat these cases in a timely manner. Consequently, beyond its individual effects, the infection also impacts the economy of the countries where it is prevalent, generating a need to consider the hypothesis of implementing Chlamydia Screening Programs, a decision that, although it is expensive to execute, is a necessary investment that unequivocally will bring financial and social long-term advantages worldwide. To detect Ct infection, there are different methodologies available. Nucleic acid amplification tests, with their high sensitivity and specificity, are currently the first-line tests for the detection of Ct. When replaced by other detection methods, there are more false negative tests, leading to underreported cases and a subsequent underestimation of Ct infection's prevalence. Ct treatment is based on antibiotic prescription, which is highly associated with drug resistance. Therefore, currently, there have been efforts in line with the development of alternative strategies to effectively treat this infection, using a drug repurposing method, as well as a natural treatment approach. In addition, researchers have also made some progress in the Ct vaccine development over the years, despite the fact that it also necessitates more studies in order to finally establish a vaccination plan. In this review, we have focused on the therapeutic options for treating Ct infection, expert recommendations, and major difficulties, while also exploring the possible avenues through which to face this issue, with novel approaches beyond those proposed by the guidelines of Health Organizations.

In vitro inhibitory effect of Hydrocotyle bonariensis Lam. extracts over Chlamydia trachomatis and Chlamydia pneumoniae on different stages of the chlamydial life cycle

Chlamydial infections in humans are widely distributed and are responsible for a variety of acute and chronic diseases. Both Chlamydia trachomatis and Chlamydia pneumoniae can lead to chronic conditions that have been linked to complications and sequelae. This study aimed to develop a culture method in order to detect in vitro antichlamydial activity of different extracts obtained from native Argentinian plants used as antimicrobials in local ethnomedicine and to evaluate their inhibitory activity over Chlamydia trachomatis and Chlamydia pneumoniae growth. The inhibitory activity over different stages of the chlamydial life cycle on cell culture was assessed: the entry, the inclusion developing after entry, and the exponential growth stage. Also, the capability of rendering the cell refractory to chlamydial infection by pre-incubation with the extracts was assayed. Inhibitory activity of water-based and organic-based extracts obtained from Hydrocotyle bonariensis Lam. (Araliaceae), Lithraea molleoides (Vell.) Engl. (Anacardiaceae) and Hybanthus parviflorus (Mutis ex L.f.) Baill. (Violaceae) were tested against five strains of Chlamydia trachomatis (L2/434/BU and four clinical isolates form both neonatal conjunctivitis and adult genital infections, genotypes D, E, and K) and against Chlamydia pneumoniae AR39. The Hydrocotyle bonariensis dichloromethane extract showed a broad inhibitory activity over the exponential growth stage of Chlamydia trachomatis and Chlamydia pneumoniae independently from the chlamydial strain and the cell line. These results suggest a high inhibitory potential on both Chlamydiae species. In order to characterize the Hydrocotyle bonariensis dichloromethane active extract, an ¹H-NMR was performed. The ¹H-NMR characterization showed a spectrum with characteristic signals of the fatty acid moiety of lipids or cerebrosides, volatile phenolics, phytosterols, methyl triterpenes signals, and glucose moiety of the cerebrosides.