The interrelation of HIV, cervical human papillomavirus, and neoplasia among antenatal clinic attenders in Tanzania.

OBJECTIVES: To determine the prevalence and interrelation of cervical human papillomavirus (HPV) genotypes, squamous intraepithelial lesions (SIL), HIV, and other reproductive tract infections (RTIs) among urban antenatal clinic attenders in Mwanza, Tanzania. METHODS: Genital swabs were collected from 660 pregnant women and tested for a range of RTIs and for cervical cytology. Cervical HPV-DNA was detected by PCR and genotyped. HIV and syphilis serologies were performed. RESULTS: HPV prevalence was 34% (209/612 women). Of the 144 typeable samples, 83% were high risk (HR-HPV) oncogenic strains (56% HPV 16 related types). SIL was detected in 43 women (7%), with high grade SIL in 3%. There was a high prevalence of HIV (15%), and of any RTI (83%). Genital warts were detected in 20 women (3%). HPV infection was associated with some behavioural factors (short duration of relationship, single status, not using condoms) and gonorrhoea. There was no overall association between HPV and HIV (OR=1.02, 95% CI 0.6-1.6), but a non-significant trend towards a stronger association with HR-HPV in women aged 15-19 (OR=2.79, 95% CI 0.8-9.5) and women aged > or =30 (OR=3.20, 95% CI 0.7-15). SIL was associated with HPV (OR=3.66, 95% CI 1.9-7.0), but not significantly with HIV (OR=1.54, 95% CI 0.7-3.4). Prevalence of SIL was higher among women dually positive for HPV/HIV compared to HPV infection only (21% v 12%), although this difference was not statistically significant (p=0.17). CONCLUSIONS: HPV infection was highly prevalent in this young antenatal population. The association of HIV with HR-HPV types in older women may suggest that the principal HIV/HPV interaction in this population is for HIV to upregulate HPV persistence, leading to subsequent development of SIL.

Validation of a WHO algorithm with risk assessment for the clinical management of vaginal discharge in Mwanza, Tanzania.

OBJECTIVES: (i) To determine the microbial aetiologies of vaginal discharge in STD clinic and antenatal clinic (ANC) attenders; (ii) to evaluate the performance and costs of a new WHO algorithm for the detection of gonococcal and chlamydial infections in women complaining of vaginal discharge and/or genital itching, using a risk assessment. METHODS: Two groups were enrolled: (i) 395 consecutive female patients attending a hospital outpatient clinic complaining of genital discharge or itching; and (ii) 628 consecutive pregnant women reporting at an urban ANC these symptoms. Patients were interviewed by a nurse, who applied the WHO risk score. They were then referred to the study room for interview concerning the same and other risk factors, examined, and sampled for Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT), Trichomonas vaginalis (TV), and Candida albicans (CA). Sensitivity, specificity, positive predictive value, overtreatment and correct treatment rates, and cost of drugs per true case treated were estimated. RESULTS: The prevalence of NG and/or CT infections was 11.4% and 8% at the STD clinic and the ANC respectively. The most prevalent pathogens were CA (38% at both clinics) and TV (25% at the STD clinic and 34% at the ANC). The sensitivity of the WHO algorithm for NG and/or CT was 62% at the STD clinic and 46% at the ANC, and the specificities were 64% and 84% respectively. The operational feasibility of the method was good. The cost of drugs per true case treated in applying the risk assessment approach was $3.5 among nonpregnant women and $5.0 among pregnant women. This compared favourably with respective costs of $8.8 and $25.0 in applying the syndromic management alone. CONCLUSIONS: The WHO risk assessment algorithm for the diagnosis of NG and/or CT infections among women complaining of genital discharge can considerably reduce overtreatment of NG and/or CT in both pregnant and non-pregnant women, but in this study it failed to identify 38% of non-pregnant and 54% of pregnant women with these infections. The elements of the risk score may need adjustment in different settings.

Risk scores to detect cervical infections in urban antenatal clinic attenders in Mwanza, Tanzania.

BACKGROUND: Detection and management of gonococcal and/or chlamydial infections in women is a challenge, particularly in developing countries where laboratory tests are not always available. The World Health Organisation (WHO) has developed a risk assessment approach to identify cervical infections among women complaining of vaginal discharge. We have evaluated this approach as a screening strategy among women attending an urban antenatal clinic (ANC) in Tanzania. OBJECTIVES: (i) To measure the prevalence of pathogens associated with sexually transmitted diseases (STD) and reproductive tract infections (RTI) in an urban population of ANC attenders in Tanzania; (ii) to examine characteristics of pregnant women associated with cervical infections; and (iii) to evaluate the performance of a WHO risk assessment algorithm and alternative risk scores for the detection of cervical infections in pregnant women. METHODS: A systematic sample of 660 pregnant women reporting for routine antenatal care at an urban clinic was enrolled. Women were interviewed by a nurse, who applied the WHO risk score. They were referred to a study room for interview about sociodemographic and behavioural factors, examination, and sampling for Neisseria gonorrhoeae, Chlamydia trachomatis, Trichomonas vaginalis, Candida albicans, and bacterial vaginosis. Sensitivity, specificity, positive predictive value (PPV), and theoretical cost per true case treated were estimated for the diagnosis of cervical infection with N gonorrhoeae and/or C trachomatis for the WHO and other risk scores. RESULTS: The prevalence of any vaginal or cervical infection was 68%. Prevalence rates of various pathogens were: C albicans 39%, T vaginalis 16%, bacterial vaginosis 24%, N gonorrhoeae 2.3%, C trachomatis 5.9%, any cervical infection (N gonorrhoeae and/or C trachomatis) 7.4%. The WHO score identified only five of 49 women with N gonorrhoeae and/or C trachomatis (sensitivity 10.2%). The specificity and the PPV were 92% and 9.8% respectively. The theoretical cost per true case treated on the basis of the WHO score was over $18. Several risk factors were associated with cervical infection on univariate analysis, but only six remained significant at the 10% level after multivariate analysis. These were: never use of contraceptives (OR 3.09), more than one partner in the past 3 months (OR 3.32), partner with symptoms of genital discharge syndrome (GDS) (OR 7.55), frothy vaginal discharge (OR 1.88), 5-19 polymorphonucleocytes per high power field on cervical smear (OR 3.28), or more than 20 polymorphonucleocytes per high power field (OR 16.08), and wet preparation showing evidence of T vaginalis infection (OR 1.96). Scores based on these variables failed to attain high sensitivities or PPVs (all below 40%) although the costs per true case treated were cheaper than for the WHO score. CONCLUSION: Risk assessment for the screening and management of N gonorrhoeae and/or C trachomatis among women presenting at routine antenatal services appears feasible and acceptable, but of limited value in this population because of its low sensitivity. The optimal risk score may vary considerably from one place to another. The quest for simple, cheap, and reliable tests to diagnose N gonorrhoeae and C trachomatis infections still remains a high priority on the international STD technology research agenda.