Christina Grube

Characterization of Human Immunodeficiency Virus Type 1 (HIV-1) Diversity and Tropism in 145 Patients With Primary HIV-1 Infection

BACKGROUND In the context of sexual transmission of human immunodeficiency virus type 1 (HIV-1), current findings suggest that the mucosal barrier is the major site of viral selection, transforming the complex inoculum to a small, homogeneous founder virus population. We analyzed HIV-1 transmission in relation to viral and host characteristics within the Zurich primary HIV-1 infection study. METHODS Clonal HIV-1 envelope sequences (on average 16 clones/patient) were isolated from the first available plasma samples during the early phase of infection from 145 patients with primary HIV-1 infection. Phylogenetic and tropism analyses were performed. Differences of viral diversities were investigated in association with several parameters potentially influencing HIV-1 transmission, eg, concomitant sexually transmitted infections (STIs) and mode of transmission. RESULTS Median viral diversity within env C2-V3-C3 region was 0.39% (range 0.04%-3.23%). Viral diversity did not correlate with viral load, but it was slightly correlated with the duration of infection. Neither transmission mode, gender, nor STI predicted transmission of more heterogeneous founder virus populations that were found in 16 of 145 patients (11%; diversity >1%). Only 2 patients (1.4%) were assuredly infected with CXCR4-tropic HIV-1 within a R5/X4-tropic--mixed population, as revealed and confirmed using several genotypic prediction algorithms and phenotypic assays. CONCLUSIONS Our findings suggest that transmission of multiple HIV-1 variants might be a complex process that is not dependent on mucosal factors alone. CXCR4-tropic viruses can be sexually transmitted in rare instances, but their clinical relevance remains to be determined.

HIV-1 transmission after cessation of early antiretroviral therapy among men having sex with men.

Objective:To study transmission dynamics during acute infection, during the aviremic phase over the period of early antiretroviral therapy (ART) and during the phase of viral rebound after early treatment was stopped. Methods:Transmission dynamics was assessed within 111 patients, enrolled in the Zurich primary HIV infection study, by molecular epidemiological methods using pol sequences from genotypic resistance tests and clonal env C2–V3–C3 sequences. Coclustering of Zurich primary HIV infection sequences with 12 303 sequences from 8837 HIV-positive patients enrolled in the multisite Swiss HIV Cohort Study was identified. Furthermore, we investigated transmission patterns within phylogenetic clusters by using longitudinal clinical data and analyzed HIV transmission by stage of infection and attempted to localize transmission events to periods before or after early ART. Results:Six transmission clusters comprising 20 men having sex with men were identified. Furthermore, linkage to eight men having sex with men from the Swiss HIV Cohort Study could be established. Strikingly, we detected at least five new primary infection events originating from Zurich primary HIV infection patients within 16–61 weeks after stopping early ART. Viral loads of likely index patients varied from 314 up to 1 690 000 HIV-1 RNA copies/ml of plasma at the estimated time of infection. Conclusion:The large number of new infections originating from men having sex with men who stopped early ART indicates that current preventive efforts are insufficient. In contrast, these patients showed no adherence problems. These findings argue for early, continuous ART in sexually active HIV-1-infected persons not only for individual patient benefits but also specifically to reduce the spread of HIV-1.

Efficient Suppression of Minority Drug-Resistant HIV Type 1 (HIV-1) Variants Present at Primary HIV-1 Infection by Ritonavir-Boosted Protease Inhibitor-Containing Antiretroviral Therapy

BACKGROUND Selection of preexisting minority variants of drug-resistant human immunodeficiency virus type 1 (HIV-1) can lead to virological failure in patients who receive antiretroviral therapy (ART) with low genetic resistance barriers. We studied treatment response and dynamics of minority variants during the first weeks of ART containing a ritonavir-boosted protease inhibitor (PI) and 2 nucleoside reverse-transcriptase inhibitors (NRTIs), which is a regimen with a high genetic resistance barrier. METHODS Plasma samples obtained prior to initiation of ART from 109 patients with primary HIV infection and samples obtained during viral decay during early ART from 17 of these 109 patients were tested by allele-specific polymerase chain reaction for K103N and M184V variants. RESULTS K103N and/or M184V mutations were detected in 15 (13.8%) of 109 patients prior to ART as minority variants. No selection of these variants was observed within the first weeks of ART in 7 of 15 patients with preexisting drug resistance mutations, nor was any selection observed in 10 patients without preexisting drug resistance mutations. Most patients received ART immediately after diagnosis of HIV-1 infection, showed a rapid decrease in viral load, and experienced sufficient suppression of viremia for 48 months. CONCLUSIONS Minority variants, in particular viruses harboring the M184V mutation, were efficiently suppressed in patients with acute infection who received a ritonavir-boosted PI and 2 NRTIs (most regimens included lamivudine). Under this high genetic resistance barrier regimen, the M184V was not further selected.

Frequency and Spectrum of Unexpected Clinical Manifestations of Primary HIV-1 Infection

BACKGROUND Prospectively and systematically collected data on frequency and spectrum of unexpected clinical manifestations during primary human immunodeficiency virus (HIV) infection (PHI) have not been published. METHODS We prospectively enrolled 290 patients with documented PHI in the Zurich Primary HIV Infection Study. Typical acute retroviral syndrome (ARS) was defined as fever plus at least 1 symptom or sign typically considered to be associated with ARS; in absence of fever, presence of 2 or more ARS symptoms or signs. Atypical ARS was defined as lack of symptoms or signs, a single symptom or sign only and absence of fever, presence of symptoms or signs that are not considered typically associated with ARS, or occurrence of an opportunistic disease. Time to diagnosis was calculated based on estimated date of infection and first positive HIV test. RESULTS We analyzed 290 patients (271 males). PHI manifested with typical ARS in 202 (70%) and with atypical ARS in 88 (30%) patients. Patients with atypical ARS were hospitalized 4 times more often compared with typical ARS (43% vs 11%; P < .001). The gastrointestinal tract was the most frequent organ system affected in patients with atypical manifestations. Only in 112 (38%) patients was HIV infection suspected during the first medical attendance. Patients with typical ARS were diagnosed slightly earlier compared with atypical ARS, but this difference was not significant (P = .3). CONCLUSIONS Unexpected clinical presentations occurred in a large fraction of patients with PHI and were associated with substantial morbidity. Universal HIV testing may be mandatory in high-risk groups.

Origin of Minority Drug-Resistant HIV-1 Variants in Primary HIV-1 Infection

BACKGROUND Drug-resistant human immunodeficiency virus type 1 (HIV-1) minority variants (MVs) are present in some antiretroviral therapy (ART)-naive patients. They may result from de novo mutagenesis or transmission. To date, the latter has not been proven. METHODS MVs were quantified by allele-specific polymerase chain reaction in 204 acute or recent seroconverters from the Zurich Primary HIV Infection study and 382 ART-naive, chronically infected patients. Phylogenetic analyses identified transmission clusters. RESULTS Three lines of evidence were observed in support of transmission of MVs. First, potential transmitters were identified for 12 of 16 acute or recent seroconverters harboring M184V MVs. These variants were also detected in plasma and/or peripheral blood mononuclear cells at the estimated time of transmission in 3 of 4 potential transmitters who experienced virological failure accompanied by the selection of the M184V mutation before transmission. Second, prevalence between MVs harboring the frequent mutation M184V and the particularly uncommon integrase mutation N155H differed highly significantly in acute or recent seroconverters (8.2% vs 0.5%; P < .001). Third, the prevalence of less-fit M184V MVs is significantly higher in acutely or recently than in chronically HIV-1-infected patients (8.2% vs 2.5%; P = .004). CONCLUSIONS Drug-resistant HIV-1 MVs can be transmitted. To what extent the origin-transmission vs sporadic appearance-of these variants determines their impact on ART needs to be further explored.

Acute Cytomegalovirus Colitis Presenting during Primary HIV Infection: an Unusual Case of an Immune Reconstitution Inflammatory Syndrom

Severe ulcerous cytomegalovirus pancolitis developed during primary human immunodeficiency virus (HIV) infection in a patient who underwent early combination antiretroviral treatment. This massive inflammatory process led to acute colon perforation. Serological testing demonstrated cytomegalovirus reactivation. Severe immunosuppression caused by primary HIV infection resulted in cytomegalovirus colitis, and initiation of early combination antiretroviral therapy triggered an immune reconstitution inflammatory syndrome potentially leading to colonic perforation.

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.

Reappearance of minority K103N HIV-1 variants after interruption of ART initiated during primary HIV-1 infection.

Background In the Zurich Primary HIV infection study (ZPHI), minority drug-resistant HIV-1 variants were detected in some acutely HIV-1-infected patients prior to initiation of early antiretroviral therapy (ART). Here, we investigated the reappearance of minority K103N and M184V HIV-1 variants in these patients who interrupted efficient early ART after 8–27 months according to the study protocol. These mutations are key mutations conferring drug resistance to reverse transcriptase inhibitors and they belong to the most commonly transmitted drug resistance mutations. Methodology/Principal Findings Early ART was offered to acutely HIV-1-infected patients enrolled in the longitudinal prospective ZPHI study. Six patients harboring and eleven patients not harboring drug-resistant viruses at low frequencies prior to ART were included in this substudy. Minority K103N and M184V HIV-1 variants were quantified in longitudinal plasma samples after treatment interruption by allele-specific real-time PCR. All 17 patients were infected with HIV-1 subtype B between 04/2003 and 09/2005 and received LPV/r+AZT+3TC during primary HIV-1 infection (PHI). Minority K103N HIV-1 variants reappeared after cessation of ART in two of four patients harboring this variant during PHI and even persisted in one of those patients at frequencies similar to the frequency observed prior to ART (<1%). The K103N mutation did not appear during treatment interruption in any other patient. Minority M184V HIV-1 variants were detected in two patients after ART interruption, one harboring and one not harboring these variants prior to ART. Conclusion Minority K103N HIV-1 variants, present in acutely HIV-1 infected patients prior to early ART, can reappear and persist after interruption of suppressive ART containing two nucleoside/nucleotide analogue reverse transcriptase inhibitors and a ritonavir-boosted protease inhibitor. Trial Registration Clinicaltrials.gov NCT00537966

Interferon α–Enhanced Clearance of Group A Streptococcus Despite Neutropenia

BACKGROUND Neutrophils and monocytes are crucial for controlling bacterial infections. More-frequent bacterial infections are accordingly encountered in neutropenic patients undergoing chemotherapy. This is not the case for pegylated interferon α (IFN-α)-induced neutropenia. We hypothesized that IFN-α induces a compensatory innate antibacterial state that prevents bacterial infections despite the neutropenia. METHODS To investigate whether patients with hepatitis C virus infection treated with IFN-α killed group A Streptococcus (GAS) better than before initiating therapy, whole blood was used to perform ex vivo GAS killing assays before, during, and after IFN-α therapy. RESULTS We found that IFN-α therapy enhanced GAS killing in whole blood ex vivo despite the decreased neutrophil and monocyte numbers during IFN-α therapy. IFN-α also boosted neutrophil- and monocyte-mediated GAS killing in vitro. Underlying mechanisms included increased production of the antibacterial properdin, a regulator of the complement activation, as well as reactive oxygen species. CONCLUSIONS These findings help to explain the rather discrepant facts of neutropenia but preserved antibacterial immune defenses in patients treated with IFN-α.

High Rates of Subsequent Asymptomatic Sexually Transmitted Infections and Risky Sexual Behavior in Patients Initially Presenting With Primary Human Immunodeficiency Virus-1 Infection

Background Knowledge of the risk factors of individuals with an asymptomatic sexually transmitted infection (STI) is essential for implementation of targeted STI screening strategies. Methods Between June 2015 and January 2017, an STI screening was offered to all participants in the Zurich Primary human immunodeficiency virus (HIV)-1 Infection study. Patients were tested for gonorrhea, chlamydia, syphilis, and hepatitis C virus (HCV). Results Of 214 participants, 174 (81%) were screened at least once. Most patients were men who have sex with men (MSM) (87.4%). Presenting with a primary HIV infection was associated with higher odds for later risky sexual behavior, as compared with presenting in the chronic phase (odds ratio [OR], 5.58; 95% confidence interval [CI], 3.68-8.8). In total, 79 STIs were detected, reflecting a high period prevalence of 33.3% (58 of 174 patients). Sixty-six percent of patients (52 of 79) were asymptomatic. Most common STIs were chlamydia (50.6%; 40 of 79 patients), gonorrhea (25.3%; 20 of 79), and syphilis (19%; 15 of 79). In a multivariable model, engaging in insertive (OR, 6.48; 95% CI, 1.14-36.76) or both insertive and receptive (4.61; 1.01-20.96) anal intercourse, STI symptoms (3.4; 1.68-6.89), and condomless sex (2.06; 1.14-3.74) were positively correlated with a positive screening result. The hazard of an incident STI increased with the presence of STI symptoms (hazard ratio, 3.03; 95% CI, 1.17-7.84) and any recent drug use (2.63; 1-6.9). Conclusions A trimonthly STI screening including asymptomatic individuals should be considered in this population, particularly in MSM who report sexual risk behavior. Clinical Trial Registration NCT 00537966.