Modelling-based evaluation of the costs, benefits and cost-effectiveness of multipathogen point-of-care tests for sexually transmitted infections in symptomatic genitourinary medicine clinic attendees.

OBJECTIVES: To quantify the costs, benefits and cost-effectiveness of three multipathogen point-of-care (POC) testing strategies for detecting common sexually transmitted infections (STIs) compared with standard laboratory testing. DESIGN: Modelling study. SETTING: Genitourinary medicine (GUM) services in England. POPULATION: A hypothetical cohort of 965 988 people, representing the annual number attending GUM services symptomatic of lower genitourinary tract infection. INTERVENTIONS: The decision tree model considered costs and reimbursement to GUM services associated with diagnosing and managing STIs. Three strategies using hypothetical point-of-care tests (POCTs) were compared with standard care (SC) using laboratory-based testing. The strategies were: A) dual POCT for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG); B) triplex POCT for CT-NG and Mycoplasma genitalium (MG); C) quadruplex POCT for CT-NG-MG and Trichomonas vaginalis (TV). Data came from published literature and unpublished estimates. PRIMARY AND SECONDARY OUTCOME MEASURES: Primary outcomes were total costs and benefits (quality-adjusted life years (QALYs)) for each strategy (2016 GB, £) and associated incremental cost-effectiveness ratios (ICERs) between each of the POC strategies and SC. Secondary outcomes were inappropriate treatment of STIs, onward STI transmission, pelvic inflammatory disease in women, time to cure and total attendances. RESULTS: In the base-case analysis, POC strategy C, a quadruplex POCT, was the most cost-effective relative to the other strategies, with an ICER of £36 585 per QALY gained compared with SC when using microcosting, and cost-savings of £26 451 382 when using tariff costing. POC strategy C also generated the most benefits, with 240 467 fewer clinic attendances, 808 fewer onward STI transmissions and 235 135 averted inappropriate treatments compared with SC. CONCLUSIONS: Many benefits can be achieved by using multipathogen POCTs to improve STI diagnosis and management. Further evidence is needed on the underlying prevalence of STIs and SC delivery in the UK to reduce uncertainty in economic analyses.

Cost-effectiveness analysis of annual Trichomonas vaginalis screening and treatment in HIV-positive women to prevent HIV transmission.

BACKGROUND: Because of a high incidence of Trichomonas infection among HIV-positive women, annual screening and treatment are recommended. Trichomonas infection is associated with a 2-fold risk of HIV transmission. The objective of this study was to determine if annual screening is cost-effective for the prevention of new HIV cases in susceptible male partners secondary to Trichomonas infection in HIV-positive women. METHODS: A decision tree analysis was constructed to model the costs of Trichomonas screening, treatment, and follow-up. 200 women cycled through the model for a period of 12 months. One hundred women were unscreened and 100 were screened and treated per recommendations. RESULTS: Annual Trichomonas screening and treatment saves US $553 (US $475- US $645) per woman in the prevention of HIV transmission to male partners. The cost-effectiveness of this strategy was maintained across all assumptions in a sensitivity analysis. CONCLUSIONS: Trichomonas screening and treatment for the purpose of decreasing new HIV infections is not only cost-effective but also cost saving in HIV-positive women. If Centers for Disease Control and Prevention treatment guidelines were followed in all HIV-positive women living in the United States, the lifetime cost of new HIV infections prevented would approximate US $159,264,000 and could potentially prevent new HIV cases secondary to female-to-male transmissions.

"Shotgun" versus sequential testing. Cost-effectiveness of diagnostic strategies for vaginitis.

BACKGROUND: Although vaginitis is a common outpatient problem, only 60% of patients can be diagnosed at the initial office visit of a primary care provider using the office procedures of pH testing, whiff tests, normal saline, and potassium hydroxide preps. OBJECTIVE: To determine the most cost-effective diagnostic and treatment approach for the medical management of vaginitis. DESIGN: Decision and cost-effectiveness analyses. PARTICIPANTS: Healthy women with symptoms of vaginitis undiagnosed after an initial pelvic exam, wet mount preparations, pH, and the four criteria to diagnose bacterial vaginosis. SETTING: General office practice. METHODS: We evaluated 28 diagnostic strategies comprised of combinations of pH testing, vaginal cultures for yeast and Trichomonas vaginalis, Gram's stain for bacterial vaginosis, and DNA probes for Neisseria gonorrhoeae and Chlamydia. Data sources for the study were confined to English language literature. MEASUREMENT: The outcome measures were symptom-days and costs. RESULTS: The least expensive strategy was to perform yeast culture, gonorrhoeae and Chlamydia probes at the initial visit, and Gram's stain and Trichomonas culture only when the vaginal pH exceeded 4.9 (330 dollars, 7.30 symptom days). Other strategies cost 8 dollars to 76 dollars more and increased duration of symptoms by up to 1.3 days. In probabilistic sensitivity analysis, this strategy was always the most effective strategy and was also least expensive 58% of the time. CONCLUSIONS: For patients with vaginitis symptoms undiagnosed by pelvic examination, wet mount preparations and related office tests, a comprehensive, pH-guided testing strategy at the initial office visit is less expensive and more effective than ordering tests sequentially.

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.