Symptomatic primary HIV infection or risk experiences? Circumstances surrounding HIV testing and diagnosis among recent seroconverters

Predictors of human immunodeficiency virus (HIV) infection in primary care among adults living in developed countries: a systematic review

BACKGROUND

Early diagnosis of human immunodeficiency virus (HIV) is important because antiretroviral therapies are more effective if infected individuals are diagnosed early. Diagnosis of HIV relies on laboratory testing and determining the demographic and clinical characteristics of undiagnosed HIV-infected patients may be useful in identifying patients for testing. This systematic review aims to identify characteristics of HIV-infected adults prior to diagnosis that could be used in a prediction model for early detection of patients for HIV testing in UK primary care.

METHODS

The population of interest was adults aged ≥ 18 years in developed countries. The exposures were demographic, socio-economic or clinical characteristics associated with the outcome, laboratory confirmed HIV/AIDS infection. Observational studies with a comparator group were included in the systematic review. Electronic searches for articles from January 1995 to April 2016 were conducted on online databases of EMBASE, MEDLINE, The Cochrane Library and grey literature. Two reviewers selected studies for inclusion. A checklist was developed for quality assessment, and a data extraction form was created to collate data from selected studies.

RESULTS

Full-text screening of 429 articles identified 17 cohort and case-control studies, from 26,819 retrieved articles. Demographic and socio-economic characteristics associated with HIV infection included age, gender and measures of deprivation. Lifestyle choices identified were drug use, binge-drinking, number of lifetime partners and having a partner with risky behaviour. Eighteen clinical features and comorbid conditions identified in this systematic review are included in the 51 conditions listed in the British HIV Association guidelines. Additional clinical features and comorbid conditions identified but not specified in the guidelines included hyperlipidemia, hypertension, minor trauma and diabetes.

CONCLUSION

This systematic review consolidates existing scientific evidence on characteristics of HIV-infected individuals that could be used to inform decision making in prognostic model development. Further exploration of availability of some of the demographic and behavioural predictors of HIV, such as ethnicity, number of lifetime partners and partner characteristics, in primary care records will be required to determine whether they can be applied in the prediction model.

Cross-Sectional HIV Incidence Surveillance: A Benchmarking of Approaches for Estimating the 'Mean Duration of Recent Infection'

The application of biomarkers for 'recent' infection in cross-sectional HIV incidence surveillance requires the estimation of critical biomarker characteristics. Various approaches have been employed for using longitudinal data to estimate the Mean Duration of Recent Infection (MDRI) - the average time in the 'recent' state. In this systematic benchmarking of MDRI estimation approaches, a simulation platform was used to measure accuracy and precision of over twenty approaches, in thirty scenarios capturing various study designs, subject behaviors and test dynamics that may be encountered in practice. Results highlight that assuming a single continuous sojourn in the 'recent' state can produce substantial bias. Simple interpolation provides useful MDRI estimates provided subjects are tested at regular intervals. Regression performs the best - while 'random effects' describe the subject-clustering in the data, regression models without random effects proved easy to implement, stable, and of similar accuracy in scenarios considered; robustness to parametric assumptions was improved by regressing 'recent'/'non-recent' classifications rather than continuous biomarker readings. All approaches were vulnerable to incorrect assumptions about subjects' (unobserved) infection times. Results provided show the relationships between MDRI estimation performance and the number of subjects, inter-visit intervals, missed visits, loss to follow-up, and aspects of biomarker signal and noise.

Cross-Sectional HIV Incidence Surveillance: A Benchmarking of Approaches for Estimating the 'Mean Duration of Recent Infection'

The application of biomarkers for 'recent' infection in cross-sectional HIV incidence surveillance requires the estimation of critical biomarker characteristics. Various approaches have been employed for using longitudinal data to estimate the Mean Duration of Recent Infection (MDRI) - the average time in the 'recent' state. In this systematic benchmarking of MDRI estimation approaches, a simulation platform was used to measure accuracy and precision of over twenty approaches, in thirty scenarios capturing various study designs, subject behaviors and test dynamics that may be encountered in practice. Results highlight that assuming a single continuous sojourn in the 'recent' state can produce substantial bias. Simple interpolation provides useful MDRI estimates provided subjects are tested at regular intervals. Regression performs the best - while 'random effects' describe the subject-clustering in the data, regression models without random effects proved easy to implement, stable, and of similar accuracy in scenarios considered; robustness to parametric assumptions was improved by regressing 'recent'/'non-recent' classifications rather than continuous biomarker readings. All approaches were vulnerable to incorrect assumptions about subjects' (unobserved) infection times. Results provided show the relationships between MDRI estimation performance and the number of subjects, inter-visit intervals, missed visits, loss to follow-up, and aspects of biomarker signal and noise.

Mean Recency Period for Estimation of HIV-1 Incidence with the BED-Capture EIA and Bio-Rad Avidity in Persons Diagnosed in the United States with Subtype B

HIV incidence estimates are used to monitor HIV-1 infection in the United States. Use of laboratory biomarkers that distinguish recent from longstanding infection to quantify HIV incidence rely on having accurate knowledge of the average time that individuals spend in a transient state of recent infection between seroconversion and reaching a specified biomarker cutoff value. This paper describes five estimation procedures from two general statistical approaches, a survival time approach and an approach that fits binomial models of the probability of being classified as recently infected, as a function of time since seroconversion. We compare these procedures for estimating the mean duration of recent infection (MDRI) for two biomarkers used by the U.S. National HIV Surveillance System for determination of HIV incidence, the Aware BED EIA HIV-1 incidence test (BED) and the avidity-based, modified Bio-Rad HIV-1/HIV-2 plus O ELISA (BRAI) assay. Collectively, 953 specimens from 220 HIV-1 subtype B seroconverters, taken from 5 cohorts, were tested with a biomarker assay. Estimates of MDRI using the non-parametric survival approach were 198.4 days (SD 13.0) for BED and 239.6 days (SD 13.9) for BRAI using cutoff values of 0.8 normalized optical density and 30%, respectively. The probability of remaining in the recent state as a function of time since seroconversion, based upon this revised statistical approach, can be applied in the calculation of annual incidence in the United States.

Bayesian evidence synthesis to estimate HIV prevalence in men who have sex with men in Poland at the end of 2009

HIV spread in men who have sex with men (MSM) is an increasing problem in Poland. Despite the existence of a surveillance system, there is no direct evidence to allow estimation of HIV prevalence and the proportion undiagnosed in MSM. We extracted data on HIV and the MSM population in Poland, including case-based surveillance data, diagnostic testing prevalence data and behavioural data relating to self-reported prior diagnosis, stratified by age (⩽35, >35 years) and region (Mazowieckie including the capital city of Warsaw; other regions). They were integrated into one model based on a Bayesian evidence synthesis approach. The posterior distributions for HIV prevalence and the undiagnosed fraction were estimated by Markov Chain Monte Carlo methods. To improve the model fit we repeated the analysis, introducing bias parameters to account for potential lack of representativeness in data. By placing additional constraints on bias parameters we obtained precisely identified estimates. This family of models indicates a high undiagnosed fraction [68·3%, 95% credibility interval (CrI) 53·9-76·1] and overall low prevalence (2·3%, 95% CrI 1·4-4·1) of HIV in MSM. Additional data are necessary in order to produce more robust epidemiological estimates. More effort is urgently needed to ensure timely diagnosis of HIV in Poland.

Relating HIV testing patterns in Poland to risky and protective behaviour

The aim of the study was to understand HIV testing patterns needed to improve access to early HIV diagnosis, and to investigate the spread of the virus in different populations. We examined prior testing history of individuals presenting for an HIV test across all 30 voluntary testing and counselling sites in Poland, 2008-2010 to determine factors associated with the testing rate using zero-truncated Poisson regression. Of 2397 persons presenting for an HIV test, 25 (1%) were HIV positive and 470 (19.6%) were repeat testers. The proportion of repeat testers was higher among men who have sex with men (MSM) at 37% (90/246), and people who inject drugs (PWID) at 32% (21/65). Higher testing rate was independently associated with exposure category (testing rate ratio, RR for MSM = 2.0, 95% CI 1.6-2.6, and 1.6, 0.9-2.6 for PWID), >5 sex partners (1.9, 1.4-2.7), high-risk partner (1.3, 1.1-1.6), urban residence (2.1, 1.3-3.5) and higher education attainment (1.1, 1.0-1.5). Inconsistent condom use with casual partners and sex under the influence of alcohol were associated with lower testing rates. There is a need to increase HIV testing uptake in Poland, especially among the rural population. Despite testing rates being higher among populations with higher risk of exposure to HIV (MSM and PWID), they still remain low, indicating the existence of barriers to testing.

HIV Testing and Diagnosis Rates in Kiev, Ukraine: April 2013-March 2014

Objective

Data from Ukraine on risk factors for HIV acquisition are limited. We describe the characteristics of individuals testing for HIV in the main testing centres of the Ukrainian capital Kiev, including HIV risk factors, testing rates, and positivity rates.

Methods

As part of a larger study to estimate HIV incidence within Kiev City, we included questions on possible risk factors for HIV acquisition and testing history to existing systems in 4 infectious disease clinics. Data were provided by the person requesting an HIV test using a handheld electronic tablet. All persons (≥16yrs) presenting for an HIV test April 2013–March 2014 were included. Rates per 100,000 were calculated using region-specific denominators for Kiev.

Results

During the study period 6370 individuals tested for HIV, equivalent to a testing rate of 293.2 per 100,000. Of these, 467 (7.8%) were HIV-positive, with the highest proportion positive among 31–35 year olds (11.2%), males (9.4%), people who inject drugs (PWID) (17.9%) and men who have sex with men (MSM) (24.1%). Using published population size estimates of MSM, diagnosis rates for MSM ranged from 490.6to 1548.3/100,000. A higher proportion of heterosexual women compared to heterosexual men reported contact with PWID, (16% vs. 4.7%) suggesting a bridging in risk between PWID and their sexual partners.

Conclusion

Collection of HIV risk factor information in Kiev, essential for the purposes of developing effective HIV prevention and response tools, is feasible. The high percentage of MSM among those testing positive for HIV, may indicate a significant level of undisclosed sex between men in national figures.

Why do men who have sex with men test for HIV infection? Results from a community-based testing program in Seattle

BACKGROUND

The Centers for Disease Control and Prevention recommends at least annual HIV testing for men who have sex with men (MSM), but motivations for testing are not well understood.

METHODS

We evaluated data from MSM testing for HIV at a community-based program in King County, Washington. Correlates of regular testing were examined using generalized estimating equation regression models.

RESULTS

Between February 2004 and June 2011, 7176 MSM attended 12,109 HIV testing visits. When asked reasons for testing, 49% reported that it was time for their regular test, 27% reported unprotected sex, 24% were starting relationships, 21% reported sex with someone new, 21% sought sexually transmitted infection/hepatitis screening, 12% reported sex with an HIV-infected partner, 2% suspected primary HIV infection, and 16% reported other reasons. In multivariable analysis, factors associated with regular testing included having a regular health care provider and the following in the previous year: having only male partners, having 10 or more male partners, inhaled nitrite use, not injecting drugs, and not having unprotected anal intercourse with a partner of unknown/discordant status (P ≤ 0.001 for all). Men reporting regular testing reported shorter intertest intervals than men who did not (median of 233 vs. 322 days, respectively; P < 0.001).

CONCLUSIONS

Regular testing, sexual risk, and new partnerships were important drivers of HIV testing among MSM, and regular testing was associated with increased testing frequency. Promoting regular testing may reduce the time that HIV-infected MSM are unaware of their status, particularly among those who have sex with men and women or inject drugs.

High rates of late HIV diagnosis among people who inject drugs compared to men who have sex with men and heterosexual men and women in Australia

We aimed to estimate temporal trends in the proportion of HIV diagnoses which could be characterized as recent infections in Australia for men who have sex with men (MSM), people who inject drugs (PWID), and heterosexual men and women using modified back-projection methodology based on data sources from HIV/AIDS Surveillance database. The proportion of HIV diagnoses among MSM that can be classified as recent infections increased in MSM, heterosexual men and women consistently. However, after initial increases during 1996-2000, the proportion of overall recent infections estimated among PWID declined by 50% in 2007 compared to 2000 (from 23 to 11%). These data suggest that late HIV diagnoses were more common among PWID compared to other groups. Ongoing prevention efforts need to be coupled with targeted testing and treatment efforts to increase the diagnosis of recent infection in PWID and reduce apparent inequities in access to screening.

Prevalence of seroconversion symptoms and relationship to set-point viral load: findings from a subtype C epidemic, 1995-2009

OBJECTIVE

To describe symptoms, physical examination findings, and set-point viral load associated with acute HIV seroconversion in a heterosexual cohort of HIV-discordant couples in Zambia.

DESIGN

We followed HIV serodiscordant couples in Lusaka, Zambia from 1995 to 2009 with HIV testing of negative partners and symptom inventories 3 monthly, and physical examinations annually.

METHODS

We compared prevalence of self-reported or treated symptoms (malaria syndrome, chronic diarrhea, asthenia, night sweats, and oral candidiasis) and annual physical examination findings (unilateral or bilateral neck, axillary, or inguinal adenopathy; and dermatosis) in seroconverting vs. HIV-negative or HIV-positive intervals, controlling for repeated observations, age, and sex. A composite score comprised of significant symptoms and physical examination findings predictive of seroconversion vs. HIV-negative intervals was constructed. We modeled the relationship between number of symptoms and physical examination findings at seroconversion and log set-point viral load using linear regression.

RESULTS

Two thousand, three hundred and eighty-eight HIV-negative partners were followed for a median of 18 months; 429 seroconversions occurred. Neither symptoms nor physical examination findings were reported for most seroconverters. Seroconversion was significantly associated with malaria syndrome among nondiarrheic patients [adjusted odds ratio (aOR) = 4.0], night sweats (aOR = 1.4), and bilateral axillary (aOR = 1.6), inguinal (aOR = 2.2), and neck (aOR = 2.2) adenopathy relative to HIV-negative intervals. Median number of symptoms and findings was positively associated with set-point viral load (P < 0.001).

CONCLUSION

Although most acute and early infections were asymptomatic, malaria syndrome was more common and more severe during seroconversion. When present, symptoms and physical examination findings were nonspecific and associated with higher set-point viremia.

What palliative care-related problems do patients experience at HIV diagnosis? A systematic review of the evidence

CONTEXT

Palliative care is an essential element of HIV care throughout the disease trajectory, but there is a lack of information to guide clinical care at HIV diagnosis.

OBJECTIVES

This systematic review aimed to identify and appraise the evidence of palliative care-related problems at HIV diagnosis.

METHODS

The search strategy combined the term "HIV" with seven key words derived from the World Health Organization definition of multidimensional palliative care, in a systematic search of four databases. Abstracts and papers were screened to identify those recording problems within six months of HIV diagnosis in adults. Sample descriptions, aims, methods, and prevalence findings were extracted from these papers into common tables.

RESULTS

Of 5443 titles retrieved, 65 met the inclusion criteria and 34 were retained. Papers included 27 original studies and seven secondary analyses of patient's records, with great heterogeneity in design, sample definition, and outcome measures. Physical and psychological symptoms were highly prevalent (pain 11%-76%, weight loss 8%-89%, fever 32%-89%, diarrhea 6%-54%, anxiety 36%-95%, and depression 18%-47%). At HIV diagnosis, well-being was impaired, suicidal thoughts were frequent, and peace and calmness were reduced. Participants lacked emotional support and feared the reaction of their families. Practical problems included hunger, homelessness, reduced ability to work, and need for childcare. Studies had methodological failings such as the use of unvalidated tools and lack of clarity reporting results.

CONCLUSION

People who have recently been diagnosed with HIV have multidimensional palliative care-related problems. HIV care and support services need to assess and manage problems using integrated palliative care, with referral for complex problems. Patient centeredness must be a principle of HIV clinical research.

Medical encounter characteristics of HIV seroconverters in the US Army and Air Force, 2000–2004

BACKGROUND AND METHODS

Active duty US Army and Air Force military personnel undergo mandatory biennial HIV antibody screening. We compared pre- and post-HIV seroconversion health status by conducting a case-control study, which evaluated all medical encounters and sociodemographic factors among incident HIV seroconverters and HIV-negative controls from June 2000 through February 2004.

RESULTS

A total of 274 HIV seroconverters and 6205 HIV-negative personnel were included. In multivariate analysis restricted to male personnel (cases = 261, controls = 5801), single marital status (adjusted odds ratio [AOR] = 14.37), clinical indicators or symptoms within four years of HIV diagnosis (AOR = 6.22), black race (AOR = 5.88), nonindicator clinical syndromes within 2 years of HIV diagnosis (AOR = 3.31), any mental disorder within 4 years of HIV diagnosis (AOR = 3.04), increasing service-connected time (AOR = 1.69), and older age (AOR = 1.12) were associated with HIV diagnosis among males. A prior history of a sexually transmitted infection (STI) was associated with post-HIV seroconversion STI (OR(M-H) = 4.10). Similarly, a prior history of mental disorder was associated with post-HIV seroconversion mental disorder (OR(M-H) = 4.98). Forty-seven (18%) male cases were hospitalized at least once after HIV diagnosis; infectious diseases, and mental disorders made up 53% of initial admissions.

CONCLUSIONS

HIV seroconversion was associated with increased health care-seeking behavior, STIs, and mental disorders, some of which may be amenable to screening. The higher STI rate after HIV diagnosis may partially be a consequence of monitoring, but secondary transmission of STI and possibly HIV require further definition and subsequent tailored preventive interventions.

Interpopulation variation in HIV testing promptness may introduce bias in HIV incidence estimates using the serologic testing algorithm for recent HIV seroconversion

OBJECTIVES

The serologic testing algorithm for recent HIV seroconversion (STARHS) calculates incidence using the proportion of testers who produce a level of HIV antibody high enough to be detected by ELISA but low enough to suggest recent infection. The validity of STARHS relies on independence between dates of HIV infection and dates of antibody testing. When subjects choose the time of their own test, testing may be motivated by risky behaviour or symptoms of infection and the criterion may not be met. This analysis was conducted to ascertain whether estimates of incidence derived using STARHS were consistent with estimates derived using a method more robust against motivated testing.

METHODS

A cohort-based incidence estimator and two STARHS methods were applied to identical populations (n=3821) tested for HIV antibody at publicly funded sites in Seattle. Overall seroincidence estimates, demographically stratified estimates and incidence rate ratios were compared across methods. The proportion of low-antibody testers among HIV-infected individuals was compared with the proportion expected given their testing histories.

RESULTS

STARHS estimates generally exceeded cohort-based estimates. Incidence ratios derived using STARHS between demographic strata were not consistent across methods. The proportion of HIV-infected individuals with lower antibody levels exceeded that which would be expected under independence between infection and testing.

CONCLUSIONS

Incidence estimates and incidence rate ratios derived using methods that rely on the changing antibody level over the course of HIV infection may be vulnerable to bias when applied to populations who choose the time of their own testing.

Testing bias in calculating HIV incidence from the Serologic Testing Algorithm for Recent HIV Seroconversion

OBJECTIVE

Incidence is critical in monitoring HIV infection in populations but often difficult to measure. The Serologic Testing Algorithm for Recent HIV Seroconversion (STARHS) can estimate HIV incidence from a single specimen at low cost. Nevertheless, HIV testing patterns may introduce bias, rendering interpretation of the STARHS result problematic. We found empirical evidence of such bias in Ontario using the STARHS formula with varied window periods

METHODS

In a hypothetical population of homosexual men, we calculated HIV incidence from the STARHS assay on the basis of incidence density, study duration, STARHS window period and intertest interval. We also incorporated the increased likelihood of a newly infected person having an HIV test due to seroconversion illness or high-risk behaviours ('seroconversion effect' or SCE). We also varied the intertest interval inversely as a function of incidence density. To adjust incidence estimates for bias, we fit empirical STARHS data to an algebraic formula expressing measured HIV incidence as a function of SCE and incidence.

RESULTS

Incidence density estimates were unbiased when SCE or incidence density-interval interactions were absent. However, estimated incidence density was higher than true incidence density in the presence of SCE, as much as seven-fold higher under certain conditions. The goodness-of-fit provided estimates with an excellent fit, yielding plausible results.

CONCLUSION

HIV incidence from STARHS may be strongly biased because of early testing in recently infected persons, resulting in substantial overestimation, at least amongst men who have sex with men. Thus, incidence estimates from STARHS must be interpreted with considerable caution. Nevertheless, incidence estimates may be adjusted to yield unbiased results.

Serological testing algorithm shows rising HIV incidence in a UK cohort of men who have sex with men: 10 years application

OBJECTIVES

To investigate whether combining clinical data with the serological testing algorithm for recent HIV seroconversion (STARHS) reliably identifies otherwise unrecognized recent infections and observe their trends.

DESIGN

Incorporation of STARHS into routine HIV diagnosis.

METHODS

STARHS was applied to serum collected between 1996 and 2005 at HIV diagnosis and routine clinical/laboratory markers of recent infections were determined. The recent infections were identified by conventional means, by STARHS, and by both combined.

RESULTS

Of 1526 infections diagnosed, 812 were new. Of these, 604 were in men who have sex with men (MSM); 208 in heterosexuals; 88% had serum available for STARHS, which identified 88 incident infections that would otherwise have been unrecognized (12% of all new infections, 34% of all recent infections). Of these, 88% reported recent high-risk sex; 47% reported seroconversion symptoms. STARHS confirmed recent infections in 71 of 74 (96%) known to be infected within 6 months by conventional methods. Combining both approaches, recent infections increased over time from 26% (1996) to 45% (2005) [P < 0.001]. STARHS results from 3% new diagnoses and 8% previous diagnoses were deemed false incident (associated with antiretroviral therapy, advanced disease or undetectable viral load). False incident results were only inexplicable in two individuals.

CONCLUSION

Adjunctive use of STARHS with clinical data identified a high and increasing proportion of new HIV diagnoses as recent infections, confirming significant ongoing transmission. Since 2002, 50% of new diagnoses among MSM were recent infections. Identification of additional recent infections by STARHS enables effective intervention that may benefit the individual and reduce onward transmission.

Primary human immunodeficiency virus type 1 infection

Primary human immunodeficiency virus type 1 (HIV-1) infection represents the initial stage of disease that immediately follows viral entry into the body. Primary infection is frequently accompanied by an acute retroviral syndrome with associated high levels of plasma HIV-1 RNA and the development of host immune responses. The identification of subjects during this period requires a high index of suspicion and an understanding of how to make the diagnosis, as standard HIV-1 antibody tests can initially be negative. Identifying these people provides a unique opportunity for early counseling to reduce further transmission, facilitates entry into care, and allows for further study of the immunopathogenesis of disease and the potential role of early antiretroviral therapy.

Primary HIV-1 infection: Diagnosis, pathogenesis, and treatment

Primary HIV-1 infection represents the time when the virus is first disseminating throughout the body and induces host immune responses. Diagnosing this stage of disease requires an understanding of who is at risk, the clinical manifestations of primary infection, and how the diagnosis is made. Identifying these individuals allows for counseling to prevent further transmission to others and the potential benefits associated with early antiretroviral therapy. Moreover, studying these individuals provides important insight into the biology of HIV-1 transmission and immunopathogenesis.