Discussion
While T. vaginalis is indeed recognized as the most common non-viral sexually transmitted infection (STI) among women globally, it tends to present as benign and self-limiting in men (6). A study showed that the prevalence of T. vaginalis in men aged 30 years or older with urethral discharge attending STD clinics (12%) was comparable to that of Neisseria gonorrhoeae (12%) or Chlamydia trachomatis(14%) (7). This infection predominantly affects women, and in men, the majority quickly overcome the infection, suggesting a potential link to differing urogenital microenvironments. It is well-documented thatT. vaginalis can increase the risk of acquiring human immunodeficiency virus (HIV), cervical cancer, and preterm birth. However, there is limited understanding of the clinical complications of this infection in men (8). In men, T. vaginalis can induce urethritis, prostatitis, reduced fertility, and heightened risk of human immunodeficiency virus acquisition (6). Although most men experience mild symptoms, T. vaginalis has the potential to cause severe complications in this population.
It’s important to note that T. vaginalis has the potential to ascend the urethra and affect the prostate, potentially leading to prostatitis if left untreated. In our case, it seems likely that chronic trichomoniasis from multiple infected sexual partners over the past 20 years may have contributed to this situation. Several studies have indeed established a connection between chronic T. vaginalisinfection and the development of prostate cancer (6). Moreover, a study has indicated that T. vaginalis may play a role in the progression of prostatitis and BPH by creating an inflammatory microenvironment (9). To mitigate the negative effects of this infection in both men and women, it is vital to diagnose and treat T. vaginalis in men, especially as up to 72% of male sexual partners of infected women may also be affected (6). The Centers for Disease Control and Prevention (CDC) recommends treating men who have been diagnosed with trichomoniasis or who have been sexually exposed to this infection to prevent spreading it to other female sexual partners. Seeking prompt medical attention and adhering to the recommended treatment guidelines can help mitigate the potential complications associated with T. vaginalis infection in both men and their sexual partners.
The preferred treatment for T. vaginalis has traditionally been metronidazole (MTZ) at a dose of 2 g or oral tinidazole. As an alternative, a multi-dose oral MTZ regimen of 500 mg twice daily for 7 days may be used (6). A randomized controlled trial involving HIV-uninfected women showed that the multi-dose metronidazole regimen significantly decreased the proportion of women with trichomonas infection at the 1-month test of cure compared to single-dose therapy (2 g). Men have been found to benefit the most from the 2-g single-dose oral metronidazole regimen (8). Studies conducted in the United States have indicated that the average age of women and men infected withT. vaginalis was significantly higher than those infected with other STIs. Additionally, the average age of T. vaginalisinfected men was nearly a decade older than that of infected women.
When men experience changes in their reproductive hormone levels, it may lead to an increased risk of T. vaginalis infection (10). Research conducted by Lindrose et al. indicated a higher prevalence ofT. vaginalis in older age groups compared to young adults (11). Notably, our case report revealed the presence of trichomonas in a 95-year-old man, which is an unexpected finding for this age group. It is important not to overlook the possibility of this infection in elderly patients, as they face an elevated risk of inflammation, cervical cancer, and prostate cancer (11). Future studies could focus on identifying specific subgroups within the elderly population who may be at a higher risk of trichomoniasis or complications related to T. vaginalis (11). In elderly individuals who have experienced dysuria and have had multiple sexual partners, it is important to consider the possibility of T. vaginalis infection.
While T. vaginalis is widely recognized as the most prevalent non-viral sexually transmissible infections (STI) among women worldwide, it may also have significant implications for men. In men, T. vaginalis has the potential to induce urethritis, prostatitis, reduced fertility, and an increased susceptibility to acquiring the HIV. Although most men may only experience mild symptoms, it is important to acknowledge that T. vaginalis can lead to severe complications. It is worth noting that if not treated, T. vaginalis may ascend the urethra and impact the prostate, potentially resulting in prostatitis. Therefore, it is advisable to promptly treat men who have been diagnosed with trichomoniasis or have had sexual contact with an infected individual to prevent further transmission to other female sexual partners. Additionally, clinicians should not overlook the possibility of this infection in elderly men, as they face an elevated risk of inflammation and prostate cancer.