Symptomatic illness and low CD4 cell count at HIV seroconversion as markers of severe primary HIV infection

Late Diagnosis in HIV with New and Old Definitions; Data from a Regional Hospital in Turkey

Background

Late presentation for HIV care, continues to be a challenge, leading to increased morbidity, mortality, and society costs. The study aimed to determine the rates of late diagnosis (LD) and patient characteristics in Turkey, utilizing the new definition excluding recently infected.

Methods

The study included patients admitted to the hospital between 1998 and 2023, with at least 1 year of follow-up. Patients without a CD4 count at their initial admission were excluded. Two definitions of presentation were used: LD, (CD4<350 cells/mL or AIDS-defining event) and advanced disease (AD), (CD4<200 cells/mL or AIDS-defining event). Individuals with recent evidence of infection were reclassified as "not late".

Results

Out of the 914 patients meeting the criteria and the analysis focused on 794 treatment-naïve patients, with 90.6% being male and an average age of 36.0 ± 12.0 years. Using the previous definition, 48.9% were diagnosed as late, while the new definition identified 47.2%. A total of 183 patients (23%) were diagnosed with AD, and 25.9% of the diagnoses occurred during the COVID-19 Pandemic. The rate of LD increased during the pandemic compared to before (55.8% vs 44.2%, p=0.005), as did the rate of AD (30.1% vs 20.6%, p=0.007). There was no significant relationship between gender and LD. Patients with LD were older (median ages were 31 vs 36 in groups, p<0.001), had poorer virological response, higher mortality rates (4.8% vs 1.2%, p=0.003), and shorter survival compared to those without (log rank=0.004).

Conclusion

HIV patients with LD have poorer prognosis with older age as well as disruption of health services during the pandemic as risk factors. To improve outcomes, multicenter studies should investigate missed opportunities and specific risk factors in our region, and we should screen at-risk populations, promote awareness among underdiagnosed populations, and advocate testing even in disastrous situations.

Is the definition of late diagnosis correct?

BACKGROUND

The study analysed 1711 patients of the Hospital for Infectious Diseases in Warsaw diagnosed with HIV infection in 2008-2010 and 2016-2018. Research was conducted examining the changes in CD4 cell counts before starting antiretroviral (ARV) treatment in order to find people who were misclassified as late-diagnosed.

METHODS

Patients with late diagnosis were distinguished on the basis of the consensus definition. The Mann-Whitney U-test was used to analyse the change in CD4 cell counts before starting ARV treatment.

RESULTS

In the years 2008-2010, the CD4 count was remeasured before starting ARV treatment in 90 late-diagnosed patients. The median change in the CD4 count was 22 cells/μL. In 49 of these, the number of CD4 cells spontaneously increased before the start of treatment. We can suspect that these patients were misclassified as late-diagnosed.

CONCLUSIONS

The consensus definition of late diagnosis often leads to overestimation of the number of late-diagnosed patients. The crucial problem is a transient decline in the CD4 lymphocyte count in the acute phase of HIV infection. A potential solution is to introduce serum HIV viral load measurement into the definition.

Late diagnosis of HIV: An updated consensus definition

INTRODUCTION

In recent years, HIV testing frequency has increased, resulting in more people being diagnosed during seroconversion with a temporarily low CD4 count. Using the current consensus definition of late HIV presentation ('presenting for care with a CD4 count < 350 cells/μL or an AIDS-defining event, regardless of CD4 count') these individuals would be incorrectly assigned as being diagnosed late.

METHODS

In spring 2022, a European expert group convened to revise the current late HIV presentation consensus definition. A survey on data availability to apply this revised definition was sent to nominated European focal points responsible for HIV surveillance (n = 53).

RESULTS

Experts agreed that the updated definition should refer to late HIV diagnosis rather than presentation and include the following addition: People with evidence of recent infection should be reclassified as 'not late', with evidence of recent infection considered hierarchically. The individual must have: (i) laboratory evidence of recent infection; (ii) a last negative HIV test within 12 months of diagnosis; or (iii) clinical evidence of acute infection. People with evidence of being previously diagnosed abroad should be excluded. A total of 18 countries responded to the survey; 83% reported capturing CD4 count and/or AIDS at diagnosis through national surveillance, 67% captured last negative test and/or previous HIV diagnosis, 61% captured seroconversion illness at diagnosis and 28% captured incident antibody results.

CONCLUSIONS

Accurate data on late diagnosis are important to describe the effects of testing programmes. Reclassification of individuals with recent infection will help to better identify populations most at risk of poor HIV outcomes and areas for intervention.

Re-assessing the late HIV diagnosis surveillance definition in the era of increased and frequent testing

OBJECTIVES

Late HIV diagnosis (CD4 <350 cells/mm³ ) is a key public health metric. In an era of more frequent testing, the likelihood of HIV diagnosis occurring during seroconversion, when CD4 counts may dip below 350, is greater. We applied a correction, considering markers of recent infection, and re-assessed 1-year mortality following late diagnosis.

METHODS

We used national epidemiological and laboratory surveillance data from all people diagnosed with HIV in England, Wales, and Northern Ireland (EW&NI). Those with a baseline CD4 <350 were reclassified as 'not late' if they had evidence of recent infection (recency test and/or negative test within 24 months). A correction factor (CF) was the number reclassified divided by the number with a CD4 <350.

RESULTS

Of the 32 227 people diagnosed with HIV in EW&NI between 2011 and 2019 with a baseline CD4 (81% of total), 46% had a CD4 <350 (uncorrected late diagnosis rate): 34% of gay and bisexual men (GBM), 65% of heterosexual men, and 56% of heterosexual women. Accounting for recency test and/or prior negative tests gave a 'corrected' late diagnosis rate of 39% and corresponding CF of 14%. The CF increased from 10% to 18% during 2011-2015, then plateaued, and was larger among GBM (25%) than heterosexual men and women (6% and 7%, respectively). One-year mortality among people diagnosed late was 329 per 10 000 after reclassification (an increase from 288/10 000).

CONCLUSIONS

The case-surveillance definition of late diagnosis increasingly overestimates late presentation, the extent of which differs by key populations. Adjustment of late diagnosis is recommended, particularly for frequent testers such as GBM.

Detection of Broadly Neutralizing Activity within the First Months of HIV-1 Infection

A fraction of HIV-1 patients are able to generate broadly neutralizing antibodies (bNAbs) after 2 to 4 years of infection. In rare occasions such antibodies are observed close to the first year of HIV-1 infection but never within the first 6 months. In this study, we analyzed the neutralization breadth of sera from 157 antiretroviral-naive individuals who were infected for less than 1 year. A range of neutralizing activities was observed with a previously described panel of six recombinant viruses from five different subtypes (M. Medina-Ramirez et al., J Virol 85:5804-5813, 2011, http://dx.doi.org/10.1128/JVI.02482-10). Some sera were broadly reactive, predominantly targeting envelope epitopes within the V2 glycan-dependent region. The neutralization breadth was positively associated with time postinfection (P = 0.0001), but contrary to what has been reported for chronic infections, no association with the viral load was observed. Notably, five individuals within the first 6 months of infection (two as early as 77 and 96 days postinfection) showed substantial cross-neutralization. This was confirmed with an extended panel of 20 Env pseudoviruses from four different subtypes (two in tier 3, 14 in tier 2, and four in tier 1). Sera from these individuals were capable of neutralizing viruses from four different subtypes with a geometric mean 50% infective dose (ID50) between 100 and 800. These results indicate that induction of cross-neutralizing responses, albeit rare, is achievable even within 6 months of HIV-1 infection. These observations encourage the search for immunogens able to elicit this kind of response in preventive HIV-1 vaccine approaches.

IMPORTANCE

There are very few individuals able to mount broadly neutralizing activity (bNA) close to the first year postinfection. It is not known how early in the infection cross-neutralizing responses can be induced. In the present study, we show that bNAbs, despite being rare, can be induced much earlier than previously thought. The identification of HIV-1-infected patients with these activities within the first months of infection and characterization of these responses will help in defining new immunogen designs and neutralization targets for vaccine-mediated induction of bNAbs.

Late presentation to HIV testing is overestimated when based on the consensus definition

Objectives

In 2011, a consensus was reached defining “late presenters” (LPs) as individuals presenting for care with a CD4 count < 350 cells/μL or with an AIDS‐defining event, regardless of CD4 count. However, a transient low CD4 count is not uncommon in recent infections. The objective of this study was to investigate how measurements of late presentation change if the clinical stage at the time of diagnosis is taken into account.

Methods

Case surveillance data for newly diagnosed patients in Belgium in 1998–2012 were analysed, including CD4 count at diagnosis, the presence of AIDS‐defining events, and recent infections (< 6 months) as reported by clinicians in the case of acute illness or a recent negative test. First, proportions of LPs were calculated according to the consensus definition. Secondly, LPs were reclassified as “nonlate” if infections were reported as recent.

Results

A total of 7949 HIV diagnoses were included in the study. Recent infections were increasingly reported over time, accounting for 8.2% of new infections in 1998 and 37.5% in 2012. The consideration of clinical stage significantly modified the proportion of LPs: 18.2% of men who have sex with men (MSM) diagnosed in 2012 would be classified as LPs instead of 30.9% using the consensus definition (P < 0.001). The proportion of patients misclassified as LPs increased significantly over time: 5% in MSM in 1998 vs. 41% in 2012.

Conclusions

This study suggests that low CD4 counts in recent infections may lead to overestimation of late presentation when applying the consensus definition. The impact of transient CD4 count on late presentation estimates should be assessed and, if relevant, the introduction of clinical stage in the definition of late presentation should be considered.

A novel Acute Retroviral Syndrome Severity Score predicts the key surrogate markers for HIV-1 disease progression

Objective: Best long-term practice in primary HIV-1 infection (PHI) remains unknown for the individual. A risk-based scoring system associated with surrogate markers of HIV-1 disease progression could be helpful to stratify patients with PHI at highest risk for HIV-1 disease progression.

Methods: We prospectively enrolled 290 individuals with well-documented PHI in the Zurich Primary HIV-1 Infection Study, an open-label, non-randomized, observational, single-center study. Patients could choose to undergo early antiretroviral treatment (eART) and stop it after one year of undetectable viremia, to go on with treatment indefinitely, or to defer treatment. For each patient we calculated an a priori defined “Acute Retroviral Syndrome Severity Score” (ARSSS), consisting of clinical and basic laboratory variables, ranging from zero to ten points. We used linear regression models to assess the association between ARSSS and log baseline viral load (VL), baseline CD4⁺ cell count, and log viral setpoint (sVL) (i.e. VL measured ≥90 days after infection or treatment interruption).

Results

Mean ARSSS was 2.89. CD4⁺ cell count at baseline was negatively correlated with ARSSS (p = 0.03, n = 289), whereas HIV-RNA levels at baseline showed a strong positive correlation with ARSSS (p<0.001, n = 290). In the regression models, a 1-point increase in the score corresponded to a 0.10 log increase in baseline VL and a CD4⁺cell count decline of 12/µl, respectively. In patients with PHI and not undergoing eART, higher ARSSS were significantly associated with higher sVL (p = 0.029, n = 64). In contrast, in patients undergoing eART with subsequent structured treatment interruption, no correlation was found between sVL and ARSSS (p = 0.28, n = 40).

Conclusion

The ARSSS is a simple clinical score that correlates with the best-validated surrogate markers of HIV-1 disease progression. In regions where ART is not universally available and eART is not standard this score may help identifying patients who will profit the most from early antiretroviral therapy.