Detection and typing of Human Papillomavirus in urine from patients attending a sexually transmitted infections clinic in Nairobi County, Kenya

摘要

Human papillomavirus (HPV) is a common sexually transmitted infection (STI) that has been etiologically linked to cervical cancer. Different types of samples can be used for cervical screening, including Pap test or biopsy and Liquid Based Cytology, visual inspection using acetic acid or Lugol’s iodine, and HPV testing. These methods are invasive. The use of urine as an alternative specimen may be more widely accepted since it is non-invasive and the sample is readily available. The study aimed at detecting and genotyping HPV in urine from patients attending a sexually transmitted infections clinic in Nairobi County. It also aimed at assessing the factors associated with HPV infection. In this cross-sectional study, a structured ‘risk factor’ questionnaire was administered and HPV from urine specimen was genotyped using the L1 gene. Phylogenetic and molecular evolutionary analyses were conducted. Bivariate analysis and Pearson’s chi square (χ 2 ) tests were used to determine the association between HPV infection and factors associated with HPV. A total of 222 adults (45 males and 177 females) aged 18-49 years were recruited. The prevalence of HPV among males and females was 22.2% (10/45) and 32.8% (58/177) respectively. The prevalence of high-risk types among males and females was 25% (1/4) and 27.5% (11/40) respectively. The high risk HPV genotypes detected among females were: HPV-16 (10%), -66 (7.5%), and -70 (7.5%) while low risk types were HPV 6 (27.5%), followed by -81 (25%), -83 (10%), -11 (7.5%), and -54 (2.5%) respectively. The prevalence of low risk types among males and females was 75% (3/4) and 72.5% (29/40) respectively. The prevalent low-risk HPV type detected in males was HPV type 6 (75%) while HPV-58 (25%) was the only high risk type in males. History of sexually transmitted infections was significantly associated with HPV infection among females (P=0.002). There was also significant association between marital status among males (p=0.046), how often one had used the contraceptives among females (p=0.038) and HPV genotypes at bivariate level. The results indicate high HPV prevalence, high risk and low risk HPVs could be detected in urine from the two populations. Therefore; molecular testing of HPV on urine samples is a method that utilizes a non-invasive technique that may increase screening coverage as it is easy to obtain. Key words: urine, Human papillomavirus, HPV genotypes, PCR, cervical cancer.