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"Penis - virology"
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Penile Anaerobic Dysbiosis as a Risk Factor for HIV Infection
2017
Sexual transmission of HIV requires exposure to the virus and infection of activated mucosal immune cells, specifically CD4 + T cells or dendritic cells. The foreskin is a major site of viral entry in heterosexual transmission of HIV. Although the probability of acquiring HIV from a sexual encounter is low, the risk varies even after adjusting for known HIV risk factors. The genital microbiome may account for some of the variability in risk by interacting with the host immune system to trigger inflammatory responses that mediate the infection of mucosal immune cells. We conducted a case-control study of uncircumcised participants nested within a randomized-controlled trial of male circumcision in Rakai, Uganda. Using penile (coronal sulcus) swabs collected by study personnel at trial enrollment, we characterized the penile microbiome by sequencing and real-time PCR and cytokine levels by electrochemiluminescence assays. The absolute abundances of penile anaerobes at enrollment were associated with later risk of HIV seroconversion, with a 10-fold increase in Prevotella , Dialister , Finegoldia , and Peptoniphilus increasing the odds of HIV acquisition by 54 to 63%, after controlling for other known HIV risk factors. Increased abundances of anaerobic bacteria were also correlated with increased cytokines, including interleukin-8, which can trigger an inflammatory response that recruits susceptible immune cells, suggesting a mechanism underlying the increased risk. These same anaerobic genera can be shared between heterosexual partners and are associated with increased HIV acquisition in women, pointing to anaerobic dysbiosis in the genital microbiome and an accompanying inflammatory response as a novel, independent, and transmissible risk factor for HIV infection. IMPORTANCE We found that uncircumcised men who became infected by HIV during a 2-year clinical trial had higher levels of penile anaerobes than uncircumcised men who remained HIV negative. We also found that having higher levels of penile anaerobes was also associated with higher production of immune factors that recruit HIV target cells to the foreskin, suggesting that anaerobes may modify HIV risk by triggering inflammation. These anaerobes are known to be shared by heterosexual partners and are associated with HIV risk in women. Therefore, penile anaerobes may be a sexually transmissible risk factor for HIV, and modifying the penile microbiome could potentially reduce HIV acquisition in both men and women. We found that uncircumcised men who became infected by HIV during a 2-year clinical trial had higher levels of penile anaerobes than uncircumcised men who remained HIV negative. We also found that having higher levels of penile anaerobes was also associated with higher production of immune factors that recruit HIV target cells to the foreskin, suggesting that anaerobes may modify HIV risk by triggering inflammation. These anaerobes are known to be shared by heterosexual partners and are associated with HIV risk in women. Therefore, penile anaerobes may be a sexually transmissible risk factor for HIV, and modifying the penile microbiome could potentially reduce HIV acquisition in both men and women.
Journal Article
Incidence, Clearance, and Disease Progression of Genital Human Papillomavirus Infection in Heterosexual Men
by
Stoler, Mark H.
,
Guris, Dalya
,
Moreira, Edson Duarte
in
Adolescent
,
Anatomy
,
Biological and medical sciences
2014
Background. In this analysis, we examine the incidence and clearance of external genital human papillomavirus (HPV) infection among heterosexual males aged 16-24 years. Methods. A total of 1732 males aged 16-24 years old in the placebo arm of a quadrivalent HPV vaccine trial were included in this analysis. Participants were enrolled from 18 countries in Africa, the Asia-Pacific region, Europe, Latin America, and North America. Subjects underwent anogenital examinations and sampling of the penis, scrotum, and perineal/perianal regions. Results. The incidence rate of any HPV DNA genotype 6, 11, 16, and/or 18 detection was 9.0 cases per 100 person-years. Rates of HPV DNA detection were highest in men from Africa. Median time to clearance of HPV genotypes 6, 11, 16, and 18 DNA was 6.1, 6.1, 7.7, and 6.2 months, respectively. Median time to clearance of persistently detected HPV 6, 11, 16, and 18 DNA was 6.7, 3.2, 9.2, and 4.7 months, respectively. Conclusion. The study results suggest that the acquisition of HPV 6,11,16, and/or 18 in males is common and that many of these so-called infections are subsequently cleared, similar to findings for women. Nevertheless, given the high rate of HPV detection among young men, HPV vaccination of males may reduce infection in men and reduce the overall burden of HPV-associated disease in the community.
Journal Article
Acquisition and Persistence of Human Papillomavirus 16 (HPV-16) and HPV-18 Among Men With High-HPV Viral Load Infections in a Circumcision Trial in Kisumu, Kenya
by
Backes, Danielle M.
,
Hesselink, Albertus T.
,
Senkomago, Virginia
in
Adolescent
,
Adult
,
Circumcision, Male
2015
Background. Circumcision and lower human papillomavirus (HPV) viral loads in men are possibly associated with a reduced risk of HPV transmission to women. However, the association between male circumcision and HPV viral load remains unclear. Methods. Swab specimens from the glans and shaft of the penis were collected from men enrolled in a circumcision trial in Kisumu, Kenya. GP5+/6+ polymerase chain reaction (PCR) was used to identify HPV DNA types. HPV-16 and HPV-18 loads were measured with a LightCyder real-time PCR and classified as high (> 250 copies/scrape) or low (< 250 copies/scrape). Results. A total of 1159 men were randomly assigned to undergo immediate circumcision, and 1140 men were randomly assigned to the control arm (these individuals were asked to remain uncircumcised until the study ended). The hazard of acquisition of high-viral load infections in the glans was lower in the circumcision arm, compared with the control arm, for HPV-16 (hazard ratio [HR], 0.32 [95% confidence interval {CI}, .20-.49]) and HPV-18 (HR, 0.34 [95% CI, .21-. 54]). The 6-month risk of HPV persistence among men with high-viral load infections in the glans at baseline was lower in the circumcision arm, compared with the control arm, for HPV-16 (risk ratio [RR], 0.36 [95% CI, .18-. 72]) and HPV-18 (RR 0.34 [95% CI, .13-. 86]). Weaker and less precise results were obtained for shaft samples. Conclusions. Male circumcision could potentially reduce the risk of HPV transmission to women by reducing the hazard of acquisition, and the risk of persistence of high-HPV viral load infections in the glans in men.
Journal Article
Higher HPV16 and HPV18 Penile Viral Loads Are Associated With Decreased Human Papillomavirus Clearance in Uncircumcised Kenyan Men
by
Backes, Danielle M.
,
Hudgens, Michael G.
,
Meshnick, Steven R.
in
Adult
,
Chemical analysis
,
Circumcision
2016
BACKGROUNDWhether higher penile human papillomavirus (HPV) viral load is associated with a lower rate of HPV clearance remains unknown.
OBJECTIVESWe examined the association between penile HPV16 and HPV18 viral load and subsequent HPV clearance in uncircumcised Kenyan men.
STUDY DESIGNParticipants were human immunodeficiency virus (HIV)-seronegative, sexually active, 18- to 24-year-old men randomized to the control arm of a male circumcision trial in Kisumu, Kenya. Men provided exfoliated penile cells from two anatomical sites (glans/coronal sulcus and shaft) every 6 months for 2 years. GP5+/6+ polymerase chain reaction was used to identify 44 HPV-DNA types. Human papillomavirus viral load testing was conducted using a LightCyler real-time polymerase chain reaction assay; viral load was classified as high (>250 copies/scrape) or low (≤250 copies/scrape), for nonquantifiable values. The Kaplan-Meier method and Cox regression modeling were used to examine the association between HPV viral load and HPV clearance.
RESULTSA total of 1097 men, with 291 HPV16 and 131 HPV18 cumulative infections over 24 months were analyzed. Human papillomavirus clearance at 6 months after first HPV detection was lower for high versus low viral load HPV16 infections in the glans (adjusted hazard ratio [aHR], 0.65; 95% confidence interval [CI], 0.46–0.92)] and shaft (aHR, 0.44; 95% CI, 0.16–0.90), and HPV18 infections in the glans (aHR, 0.05; 95% CI, 0.01–0.17).
DISCUSSIONHigh versus low HPV viral load was associated with a reduced HPV clearance for HPV16 infections in the glans and shaft, and for HPV18 infections in the glans, among young uncircumcised men. Reduced clearance of high viral load HPV16 and HPV18 infections in men may increase HPV transmission to their female partners as well as enhance the development of penile lesions in comparison to men with low viral load HPV infections.
Journal Article
Incidence and clearance of genital human papillomavirus infection in men (HIM): a cohort study
2011
Human papillomaviruses (HPVs) cause genital warts and cancers in men. The natural history of HPV infection in men is largely unknown, and that information is needed to inform prevention strategies. The goal in this study was to estimate incidence and clearance of type-specific genital HPV infection in men, and to assess the associated factors.
Men (aged 18–70 years), residing in Brazil, Mexico, and the USA, who were HIV negative and reported no history of cancer were recruited from the general population, universities, and organised health-care systems. They were assessed every 6 months for a median follow-up of 27·5 months (18·0–31·2). Specimens from the coronal sulcus, glans penis, shaft, and scrotum were obtained for the assessment of the status of HPV genotypes.
In 1159 men, the incidence of a new genital HPV infection was 38·4 per 1000 person months (95% CI 34·3–43·0). Oncogenic HPV infection was significantly associated with having a high number of lifetime female sexual partners (hazard ratio 2·40, 1·38–4·18, for at least 50 partners
vs not more than one partner), and number of male anal-sexual partners (2·57, 1·46–4·49, for at least three male partners
vs no recent partners). Median duration of HPV infection was 7·52 months (6·80–8·61) for any HPV and 12·19 months (7·16–18·17) for HPV 16. Clearance of oncogenic HPV infection decreased in men with a high number of lifetime female partners (0·49, 0·31–0·76, for at least 50 female partners
vs not more than one partner), and in men in Brazil (0·71, 0·56–0·91) and Mexico (0·73, 0·57–0·94) compared with the USA. Clearance of oncogenic HPV was more rapid with increasing age (1·02, 1·01–1·03).
The data from this study are useful for the development of realistic cost-effectiveness models for male HPV vaccination internationally.
National Cancer Institute.
Journal Article
Profile of patients with penile cancer in the region with the highest worldwide incidence
by
Coelho, Ronald
,
Nogueira, Leudivan
,
Feitoza, Laisson
in
14/63
,
692/4025/2768/1721
,
692/4028/67/2324
2020
To determine the epidemiological, histopathological, and clinical characteristics of patients diagnosed with penile cancer in the Brazilian state of Maranhão, the region with the highest incidence worldwide. One hundred and sixteen penile cancer patients were interviewed from July 2016 to October 2018. The majority of patients lived in a rural area (57%), worked in farming (58%), had a low level of schooling or no schooling (90%), and were married or in a stable relationship (74%). The mean age was 60.4 ± 16.51 years (range, 23–93 years). Phimosis (66%), poor/moderate genital hygiene (73%), history of sexually transmitted infections (55%), and zoophilia (60%) were found in the majority of patients. Most patients had their first sexual encounter at 16.2 ± 2.8 years (range, 10–25 years), and 75% had >6 sexual partners. The most common initial symptom was pruritus (37%), and most patients waited to seek treatment (average time to treatment, 18.9 months; range, 2–84 months). Human papillomavirus (HPV)-related histologies were observed in 62% of patients. Most patients had histological grades II or III (87%), stage ≥T2 disease (84%), and lymphadenopathy at admission (42%). Penectomy was performed in 96% of patients. The population with penile cancer in the region of highest incidence in the world is marked by low socioeconomic status, high prevalence of HPV infection, and phimosis. The delay in seeking treatment is related to a very high rate of advanced cancer and aggressive surgical treatment. The high prevalence of young patients was also a striking feature.
Journal Article
Sexual behaviour and less frequent bathing are associated with higher human papillomavirus incidence in a cohort study of uncircumcised Kenyan men
by
Bailey, Robert C
,
Smith, Jennifer S
,
Snijders, Peter J F
in
Adolescent
,
Africa
,
Biological and medical sciences
2013
Objectives Data on the acquisition of human papillomavirus (HPV) infection in men are limited, especially from developing regions including Africa. The objective of this study was to characterise and determine the risk factors of HPV acquisition among a cohort of uncircumcised men participating in a randomised controlled trial (RCT) of male circumcision in Kisumu, Kenya. Methods Penile exfoliated cell specimens were collected at baseline, 6- and 12-month follow-up visits from the glans/coronal sulcus and shaft of men enrolled in the control arm of the RCT between 2002 and 2005. All participants were HIV seronegative, aged 17–24 years at baseline and remained uncircumcised over follow-up. Specimens were tested with GP5+/6+ PCR to detect 44 HPV types. Parametric frailty models were used to assess risk factors of HPV incidence. Results The median age of 966 participants was 20 years. The median follow-up time was 12.1 months. The incidence rate (IR) of any HPV infection was 49.3/1000 person-months with HPV16 having the highest IR (10.9/1000 person-months). The strongest risk factors for overall HPV incidence were bathing less frequently than daily (adjusted HR=2.6; 95% CI 1.0 to 6.5) and having ≥2 female sexual partners in the past year (adjusted HR=1.6; 95% CI 1.2 to 2.1). Conclusions HPV IRs were notably high in this cohort of high-risk, uncircumcised men from Kisumu, Kenya, with the number of sexual partners and bathing frequency being the strongest risk factors.
Journal Article
Genital Herpes Zoster
by
Bao, Chengbei
,
Ji, Chao
in
Acyclovir - therapeutic use
,
Aged
,
Antiviral Agents - therapeutic use
2024
Genital Herpes ZosterA 70-year-old man with rheumatoid arthritis presented with painful, red lesions on the right side of his penis and scrotum and on his inner right thigh and a 1-day history of difficulty urinating.
Journal Article
Analysis of Monkeypox Virus Exposures and Lesions by Anatomic Site
2024
We used cross-sectional data from 226 patients with monkeypox virus to investigate the association between anatomic exposure site and lesion development. Penile, anorectal, and oral exposures predicted lesion presence at correlating anatomic sites. Exposure site also predicted the first lesion site of the penis and anus.
Journal Article
Prevalence and genotype distribution of human papillomavirus infection in multi-anatomic sites in men who have sex with men
2025
This study aims to estimate the prevalence of human papillomavirus (HPV) infection and describe its genotype distribution in MSM in Hong Kong. In this longitudinal study on Chinese MSM, multi-anatomic site self-sampling and testing for HPV, Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) were performed following survey completion at baseline and one-year follow-up. Overall, 41% (288/701) of MSM completed self-sampled HPV testing. HPV positivity was 29% (78/270) and 33% (42/127) at any anatomic site at baseline and follow-up timepoints, respectively. By anatomic site, HPV positivity was 26%-30%, 2%-4% and 0%-1% from rectal, penile, and pharyngeal specimens, respectively. The incidence of HPV infection was 21.2/100 and 18.9/100 person-years at any anatomic site and rectal site, respectively. Among 109 successfully genotyped samples, the most prevalent were HPV 6 (17%) and HPV 11 (16%), of which 60% of the genotyped samples were vaccine-preventable. Group sex engagement and less frequent condom use were positively associated with HPV infection (P<0.05). The HPV prevalence and incidence in MSM in this study is lower than in Western countries, and low-risk HPV genotypes are more prevalent. The high proportion of vaccine-preventable HPV subtypes underscores the importance of HPV vaccination in preventing infections in MSM.
Journal Article