Higher Plasma HIV RNA Research Articles

Primary HIV infection

Primary HIV infection refers to the events surrounding acquisition of HIV infection. It is associated with a nonspecific clinical syndrome that occurs 2 to 4 weeks after exposure in 40% to 90% of individuals acquiring HIV. Patients identified before seroconversion often have very high plasma HIV RNA titers that, without treatment, gradually decrease to reach a set point. Treatment of primary HIV infection with highly active antiretroviral therapy does not prevent establishment of chronic infection. However, very early therapy could potentially decrease the viral set point, prevent viral diversification, preserve immune function, improve clinical outcomes, and decrease secondary transmission. These benefits have not yet been definitely demonstrated. Transmission of viral strains with decreased susceptibility to antiviral drugs has led to recommendations for resistance testing in primary infection before initiation of therapy. Immunomodulators and vaccines are also under study as adjuvant therapy for treatment of primary HIV infection.

Efficacy and durability of nevirapine in antiretroviral drug näive patients.

Nevirapine is a non-nucleoside reverse transcriptase inhibitor (NNRTI) that was first reported in the scientific literature in 1990. Varying doses of nevirapine (NVP) and a number of regimens containing this NNRTI have been studied in antiretroviral (ARV) näive patients. Four key studies have compared the efficacy and safety of triple drug regimens containing NVP in ARV näive, HIV-1 infected patients. The INCAS study was the first demonstration of how to use NVP in an effective and durable manner: as a component of a triple drug regimen. The COMBINE Study was a comparison of protease inhibitor (PI)-based and NVP-based triple regimens. The Atlantic Study is comparing the safety and efficacy of three triple drug regimens in ARV näive patients. In this study, treatment consists of a divergent drug regimen (PI and nucleoside reverse transcriptase inhibitors, NRTIs) targeting both HIV-1 protease and reverse transcriptase or a convergent regimen targeting reverse transcriptase alone (three NRTIs or two NRTIs plus a NNRTI). A clinical endpoint study (BI 1090) compared the efficacy and durability of multi-drug regimens in ARV näive patients with high baseline plasma HIV-1 RNA levels (pVLs) and low peripheral blood CD4+ lymphocyte counts. Data from these studies confirm that triple regimens containing NVP suppressed viral replication for up to one year, even when the ARV näive patients had low CD4+ cell counts at baseline. Nevirapine-containing regimens suppressed pVLs to < 50 copies/ mL in approximately 50% of patients in the studies discussed (Intent to Treat analyses). Data from 96 weeks of follow up in the Atlantic Study demonstrates that the regimens containing didanosine and stavudine plus indinavir or NVP were significantly more successful in suppressing pVLs to < 50 copies/mL during this period than a regimen composed of these NRTIs and lamivudine (p < or = 0.001). As with other ARV drugs, NVP should always be used as part of a fully suppressive ARV regimen. When used in this way, it is an effective ARV drug, which contributes to durable virological and immunological responses in approximately half of all treated patients. Nevirapine-containing regimens are effective in patients with advanced HIV-1 infection, i.e., low CD4+ cell counts. Data will soon be available from the 2NN Study that compares the efficacy and safety of four different regimens using NVP once daily, NVP twice daily, efavirenz once daily or a combination of NVP and efavirenz. All four arms of the study include a backbone of stavudine and lamivudine.

OCCUPATIONAL EXPOSURE TO HUMAN IMMUNODEFICIENCY VIRUS IN PEDIATRICIANS: A PREVIOUSLY UNDESCRIBED HIGH RISK GROUP

The risk of occupational HIV exposure in doctors caring for children with HIV infection is unknown. We conducted a retrospective survey among doctors at the Tygerberg Children’s Hospital during September 2001, documenting occupational exposure in the previous 2 years. The overall incidence of needle stick injuries was 62%, but it increased to 91% in junior doctors. More than 50% of junior doctors recorded occupational HIV exposure. The areas of highest risk were the pediatric and neonatal intensive care units. All doctors received postexposure prophylaxis. The risk of occupational exposure to HIV among pediatric health professionals has never been documented. Obstetric residents have previously been identified as a very high risk group. 1 In the United Kingdom, as in other developed countries, where the prevalence of HIV is low and where comprehensive programs are in place to prevent vertical transmission, pediatricians are a low risk group. 2 In South Africa the seroprevalence in women attending public antenatal clinics is 23%. 3 Although a nevirapine-based vertical transmission prevention program has since been introduced, large numbers of HIV-infected children are hospitalized. High plasma HIV RNA concentrations in infected infants may increase transmission risk in health care workers. 4, 5 Objective. Our main objective was to determine the incidence of needle stick injuries and risk of occupational exposure to HIV in doctors working at Tygerberg Children’s Hospital. Background information. Tygerberg Children’s Hospital is a 250-bed tertiary training hospital in the Western Cape Province of South Africa. Medical staff includes specialist pediatricians, specialists in training (residents), medical officers, community service doctors (1 year postinternship) and interns. Methods. We conducted a retrospective survey during September 2001, using a standardized questionnaire requesting information on occupational exposure in the preceding 2 years. All medical staff employed at that time was included. The survey had been precipitated by a spate of needle stick injuries. The study was conducted with permission of the Management Committee of Tygerberg Academic Hospital. Results. All 54 doctors completed the questionnaire. The overall incidence of needle stick injuries was 62% but increased to 91% in junior doctors (Table 1). Four people recorded more than 1 injury.TABLE 1: Overall and HIV-specific occupational exposure in pediatric doctorsA wide variety of incidents were described. Hollow bore needle injury was the most common (85%). Cleaning up after insertion of an iv catheter was the most frequently reported mode of injury (70%). Most incidents occurred outside normal working hours, when the time-adjusted relative risk was increased 4-fold. The majority of incidents occurred in the neonatal wards (24%) and intensive care units (28%). Cardiopulmonary resuscitation was associated with the highest risk in any area. All 14 doctors exposed to HIV used prophylaxis, the majority within 3 h and all within 12 h of the incident. One doctor was exposed twice. Zidovudine and lamivudine were provided. In addition in the 6 months before conducting the survey, 5 purchased a protease inhibitor, indinavir. Side effects were frequent (Table 2). Sixty-four percent said that the side effects significantly influenced their quality of life and work. However, everyone reported completing the 4-week course of prophylaxis.TABLE 2: Adverse effects experienced with HIV prophylaxisDiscussion. There have been few surveys of occupational exposure to HIV in doctors. Studies of needle stick injuries mainly involved medical students 6, 7 and did not address actual HIV exposure. In our study the overall incidence of needle stick injuries was high, but of special concern was that 57% of junior doctors reported occupational HIV exposure. This is similar to the highest levels ever recorded and in a group not previously thought to be at high risk. Residents, who perform most of the difficult procedures, and other junior personnel, who are probably less skilled, are at highest risk. Predictably the time of highest risk is when the physician is either on or post call. The majority of incidents happened while “cleaning up” after inserting an iv catheter. A similar increased risk was found in a dental teaching environment. 8 By having “sharps” containers immediately at hand or using new self-resheathing needles, risk can be reduced. 9 That respondents personally funded a protease inhibitor reflects a high level of anxiety that might have contributed to the good adherence reported. 10 Adverse events were common, although difficult to distinguish from the psychologic impact of the incident.

Post-exposure prophylaxis

The mean risk of acquiring HIV after an occupational exposure, injecting drug use or sexual exposure varies from < 0.1 to 3%. A high plasma HIV-RNA of the source increases the risk of each of the exposures. Other factors, such as the volume of the inoculum involved to which the individual was exposed, other sexually transmitted diseases and ruptures of mucous membranes are associated with a higher risk of HIV transmission. Based on the calculated risk, post-exposure prophylaxis (PEP) should be recommended. In the Netherlands, prescription of PEP in the occupational setting is a standard procedure and has proved to be feasible. This was associated with a high percentage (62%) of mild and reversible toxicity and a small percentage (2%) of serious adverse events related to antiretroviral drugs, i.e. nephrolithiasis (due to indinavir) and toxic hepatitis (due to nevirapine). In The Netherlands so far no HIV-seroconversions have been recorded after an occupational accident.

The effects of antiretroviral therapy on HIV-1 RNA loads in seminal plasma in HIV-positive patients with and without urethritis.

High seminal plasma HIV-1 RNA loads (SVL) have been reported during gonococcal, non-gonococcal and chlamydial urethritis in patients not taking antiretroviral therapy. To examine if urethritis leads to increased SVL in HIV-positive patients taking antiretroviral therapy. Men who had been taking therapy for at least 3 months were recruited: 24 had urethitis (PWU) and 16 were without urethritis (controls). At three visits, 1 week apart, blood plasma viral load (BVL) and SVL were assayed by quantitative polymerase chain reaction or the NASBA assay. Most subjects had undetectable SVL (18 PWU, 13 controls). Among those with undetectable BVL prior to first study visit, virus was undetectable in semen in 5/5 episodes of chlamydial urethritis, 6/7 episodes of non-gonococcal urethritis and 4/5 cases of gonococcal urethritis. Two PWU with undetectable BVL just prior to the first study visit had low to moderate SVL, which became undetectable by visit 2 following treatment. Of nine subjects with detectable SVL, eight had detectable BVL (3/3 controls and 5/6 PWU). Of these, 1/3 controls and 4/5 PWU (all with gonococcal urethritis) had poorly controlled BVL just prior to the first study visit. These four PWU had high SVL and one had higher levels in semen than in blood. This patient's SVL was reduced more than 20-fold following treatment for gonococcal urethritis. Effective antiretroviral therapy appeared to limit the effect of urethritis on SVL. When BVL was poorly controlled by antiretroviral therapy, high SVL occurred during gonococcal urethritis, increasing the potential risk of transmitting both wild type and drug resistant strains of HIV-1.

The association of perceived health, clinical status, and initiation of HAART (highly active antiretroviral therapy) in adolescents.

To examine factors associated with the initiation of highly active antiretroviral therapy (HAART) in adolescents to understand better how current National Institutes of Health (NIH) Guidelines are being used in practice. HIV infected and HAART-naive adolescents seen at 15 REACH clinical sites were selected. Repeated measures methodology using generalized estimating equations was applied to identify associations between subject demographic characteristics, risk behaviors, perceived health, and clinical status with the outcome measure of HAART initiation during the first 24 study months. A total of 219 subjects were eligible for analysis; HAART was prescribed in 115 (53%). Significant univariate associations with HAART prescription included lower CD4(+) T cell counts (OR = 1.7, 95% CI: 1.1-2.6), higher viral loads (OR = 2.7, 95% CI: 1.5-5.0), and calendar year of HAART prescription (OR as high as 2.4, 95% CI: 1.1-5.2). Multivariate results showed that after controlling for CD4(+) T cell counts below 500 cells/mm(3), higher plasma HIV-1 RNA (<or=10,000 copies per ml), and temporal factors, having a high school diploma/GED but no further education (OR = 2.7, 95% CI: 1.3-5.5) and subject's perception of poor health status (OR = .987; 95% CI: .975- .999) were independently associated with prescription of HAART. HAART was most likely to be prescribed during the first half of 1998 in this cohort (OR = 10.8; 95% CI: 4.0-29.0). In this first ever study of HAART prescription in adolescents infected with HIV, perception of poor health status and having a high school diploma/GED were independently associated with prescription of HAART suggesting that the personal decision to accept therapy is related to the belief that one's health is deteriorating and that the decision to prescribe therapy may be linked in some fashion to the prescriber's assessment of the patient's ability to master the regimen as well as clinical status.

Risk factors for esophageal candidiasis in a large cohort of HIV-infected patients treated with nucleoside analogues.

To assess the risk factors for esophageal candidiasis (EC), a cohort study and a case-control study were conducted using 1,368 French patients who were already participating in the Delta trial (which compared different types of antiretroviral therapy in HIV-infected patients) and who had no previous history of EC. During a median follow-up period of 19 months, 87 (6%) patients developed EC. The results of the cohort study showed an increased risk of EC associated with a low baseline CD4+ cell count (P<0.0001), a high baseline plasma HIV RNA level (P < 0.0001) and prior zidovudine therapy (P = 0.02) at entry to the study. The case-control study revealed an increased risk of EC in patients with a recent low CD4+ cell count (P < 0.0002), recent antibacterial chemotherapy (P = 0.01) and oral candidiasis (P < 0.05). Cotrimoxazole prophylaxis also increased the risk of EC (P = 0.04) in the case-control study.

Dissociation of Immunologic and Virologic Responses to Highly Active Antiretroviral Therapy

Immunologic markers, levels of HIV DNA, and infectious HIV were compared in partial responders (PR) to HAART who had high plasma HIV RNA levels but stable or increasing levels of CD4+ peripheral blood mononuclear cells (PBMC), and patients with complete failure (CF) who had very low or decreasing levels of CD4+ PBMC and high plasma HIV RNA levels. CD4 and CD8 levels were monitored by flow cytometry. Beta2-microglobulin (beta2M) and neopterin levels were measured by quantitative enzyme immunoassays. Plasma and PBMC from 11 PR and 13 CF were analyzed for infectious HIV levels in limiting dilution cultures. Polymerase chain reaction (PCR) assays were used to quantify cellular HIV DNA and plasma HIV RNA. In comparison with CF, PR had little or no CD4+ cell loss, a substantial increase in CD8+ cells, significantly fewer positive plasma HIV cultures (p = .03), lower frequencies of infectious HIV in total PBMC (p = .005) and in CD4+ PBMC (p < .001), and lower frequencies of HIV DNA in CD4+ PBMC (p = .007). Lower levels of infectious HIV and a lower frequency of CD4+ PBMC that contain "productive" HIV DNA in PR as compared with CF may contribute to the stable or increasing CD4+ PBMC levels of the PR. However, HAART may also have effects on lymphocyte homeostasis independent of its antiviral activity.

HIV-1 genotypic zidovudine drug resistance and the risk of maternal--infant transmission in the women and infants transmission study. The Women and Infants Transmission Study Group.

Although the treatment of pregnant women and their infants with zidovudine (ZDV) has been remarkably effective in preventing the perinatal transmission of human HIV-1, many potentially preventable infections still occur. To examine whether the risk of perinatal infection is increased among women who carry ZDV-resistant HIV-1, the role of genotypic ZDV resistance in perinatal transmission was evaluated. The reverse transcriptase (RT) region of clinical isolates from culture supernatants of 142 HIV-1-infected women enrolled in the Women and Infants Transmission Study (WITS), who had been treated with ZDV during pregnancy was sequenced. Results from genotypic sequencing were linked to demographic, laboratory, and obstetrical databases, and the magnitude of association of having consensus drug-resistant HIV-1 RT mutations with transmission was estimated. Twenty-five per cent (34/142) of maternal isolates had at least one ZDV-associated resistance mutation. A lower CD4 cell percentage and count (P= 0.0001) and higher plasma HIV-1 RNA (P=0.006) were associated with having any ZDV resistance mutation at delivery. Having any RT resistance mutation [odds ratio (OR): 5.16; 95% confidence interval (CI): 1.40, 18.97; P=0 0.01], duration of ruptured membranes [OR: 1.13 (1.02, 1.26) per 4 h duration; P= 0.02], and total lymphocyte count [OR: 1.06 (1.01, 1.10) per 50 cells higher level; P=0.009] were independently associated with transmission in multivariate analysis. Maternal ZDV resistant virus was predictive of transmission, independent of viral load, in these mothers with moderately advanced HIV-1 disease, many of whom had been treated with ZDV before pregnancy.

Constant mean viral copy number per infected cell in tissues regardless of high, low, or undetectable plasma HIV RNA.

Quantitative analysis of the relationship between virus expression and disease outcome has been critical for understanding HIV-1 pathogenesis. Yet the amount of viral RNA contained within an HIV-expressing cell and the relationship between the number of virus-producing cells and plasma virus load has not been established or reflected in models of viral dynamics. We report here a novel strategy for the coordinated analysis of virus expression in lymph node specimens. The results obtained for patients with a broad range of plasma viral loads before and after antiretroviral therapy reveal a constant mean viral (v)RNA copy number (3.6 log10 copies) per infected cell, regardless of plasma virus load or treatment status. In addition, there was a significant but nonlinear direct correlation between the frequency of vRNA+ lymph node cells and plasma vRNA. As predicted from this relationship, residual cells expressing this same mean copy number are detectable (frequency <2/10(6) cells) in tissues of treated patients who have plasma vRNA levels below the current detectable threshold (<50 copies/ml). These data suggest that fully replication-active cells are responsible for sustaining viremia after initiation of potent antiretroviral therapy and that plasma virus titers correlate, albeit in a nonlinear fashion, with the number of virus-expressing cells in lymphoid tissue.

Detection of Kaposi's sarcoma-associated herpesvirus in peripheral blood cells in human immunodeficiency virus infection: association with Kaposi's sarcoma, CD4 cell count, and HIV RNA levels.

Kaposi's sarcoma-associated herpesvirus (KSHV) DNA, consistently found in Kaposi's sarcoma (KS) tissues, was sought in peripheral blood mononuclear cells (PBMCs) of HIV-infected individuals. To determine quantitative relationships between the presence of KSHV DNA in PBMCs, CD4 cell counts, plasma HIV RNA levels, and the development of KS, we designed a cross-sectional study of prospectively collected PBMC samples from ongoing cohort studies. PBMCs were collected from 142 HIV-seropositive individuals in California, 7 of whom had a clinical diagnosis of KS. KSHV sequences were detected in extracted PBMC DNA by nested polymerase chain amplification using two nonoverlapping primer sets. KSHV DNA was detected in PBMCs of 5 of 7 (71%) subjects with KS and in 18 of 135 (13%) HIV-infected subjects without KS. Among HIV-seropositive individuals without KS, detection of KSHV was more common in men than women (19 versus 4%, p = 0.01) and was associated with lower mean CD4 percent (14.8 versus 20.7% CD4 cells, p = 0.03), lower mean CD4 cell count (244 versus 334 CD4 cells/microl, p = 0.05), and higher geometric mean plasma HIV RNA (4.83 versus 4.03 1og10 copies/ml, p = 0.0002). Semiquantitative analysis found 5 to 15,625 copies of KSHV per microgram of PBMC DNA with increased plasma HIV RNA levels and a trend toward increased subsequent development of KS in subjects with higher KSHV loads. The association of the presence of KSHV DNA in PBMCs with lower CD4 cell counts and higher plasma HIV RNA provides evidence of a relationship between immunosuppression, HIV replication, and KSHV expression.

Plasma virus load evaluation in relation to disease progression in HIV-infected children.

The objective of this study was to investigate the relationship of plasma HIV RNA load with survival and disease progression in HIV-infected children and to determine its correlation with cellular HIV DNA. Virus load (VL, HIV RNA copies/ml) was determined retrospectively by nucleic acid sequence-based amplification (NASBA) assay in 144 stored plasma samples between birth and 48 months in 50 children of whom 40 are alive (age range, 2-13 years). On the basis of clinical and immunologic status children were classified as rapid progressors (RPs), or nonrapid progressors (NRPs). Proviral HIV DNA quantitated by QC-PCR (quantitative competitive polymerase chain reaction) in 24 children was compared with plasma HIV RNA. At age <3 months, plasma VL <750,000 copies/ml was associated with significantly higher survival to age >2 years (p < or =0.01) compared with a VL of > or =750,000 copies/ml. Increasing mortality was observed with increasing plasma HIV RNA levels at ages 3-24 months and baseline VL of infants who died before age 24 months was significantly higher (p = 0.004) than baseline VL of those who survived beyond 24 months. Although baseline VL in infants classified as RPs was higher than that of NRPs, the difference was not statistically significant. Among surviving children 2-13 years of age, the baseline VL obtained at <24 months of age was not predictive of disease severity. Although no significant correlation was noted between plasma HIV RNA and proviral DNA, the concurrence of positive and negative results was >80%. We conclude that high plasma HIV RNA in infancy is associated with increased mortality.

Biological and virologic characteristics of primary HIV infection.

The clinical events surrounding acute HIV-1 infection have been well described, but little is known about whether the virologic course of acute HIV-1 infection influences the subsequent progression of disease. To define the virologic natural history of acute and very early HIV infection. Prospective, longitudinal cohort study. University of Washington Research Clinic 74 adults enrolled soon after acquisition of HIV (mean, 69 days). Plasma HIV-1 RNA levels; quantitative cell cultures; CD4 cell counts; and detailed clinical assessments done at study entry, biweekly for 1 month, monthly for 2 months, and quarterly thereafter. In the first 30 days after acquisition of HIV, HIV-1 RNA levels varied greatly among participants (range, 27,200 to 1.6 x 10(6) copies per mL of plasma). Levels of HIV-1 RNA decreased by a mean of 6.5% per week for the first 120 days and then increased by a mean of 0.15% per week. CD4 cell counts decreased by a mean of 5.2 cells/mm3 per week for the first 160 days and by a mean of 1.9 cells/mm3 per week thereafter (P < 0.01). Disease progressed faster in participants who sought medical care for their acute seroconversion syndrome (P = 0.01) and those who had high plasma HIV-1 RNA levels 120 to 365 days after acquisition (P < 0.01). Peak levels in the first 120 days were not predictive of disease progression. The variability in viral RNA levels associated with acute HIV-1 infection is greater than previously appreciated. Within 120 days of acquisition, plasma HIV RNA levels rapidly decrease to an inflection point, after which they gradually increase. Virus-host interactions soon after acquisition seem to have a major influence on the long-term outcome of HIV-1 disease.

Unintegrated circular HIV-1 DNA in the peripheral mononuclear cells of HIV-1-infected subjects: association with high levels of plasma HIV-1 RNA, rapid decline in CD4 count, and clinical progression to AIDS.

We observed 36 HIV-infected patients to evaluate whether the presence of tandem 2-long terminal repeat circular unintegrated HIV-1 DNA (2-LTR) in peripheral blood mononuclear cells (PBMC) at baseline was associated with acceleration of HIV disease. Detection of 2-LTR at baseline correlated with high plasma HIV-1 RNA levels (p < .01), recovery of culturable HIV-1 from plasma (p = .02), and progression to AIDS during follow-up (p = .01). More patients with 2-LTR (68%) than without 2-LTR (31%) had a decline in CD4 levels of >50 cells/mm3 over the first 18 months of follow-up (p = .04), and the average annual CD4 decline was 35% in patients with 2-LTR compared with 16% in those without 2-LTR (p = 0.06). Detection of 2-LTR in PBMC at baseline was an independent predictor of high plasma HIV-1 RNA levels and subsequent CD4 cell decline in this cohort of patients with predominantly nonsyncytium-inducing (NSI) isolates at baseline. The presence of 2-LTR in PBMC appears to be reflective of ongoing HIV-1 replication, as measured by plasma HIV-1 RNA levels, and identifies persons at risk for immunologic and clinical decline.

Neurodevelopment, Growth, and Viral Load in HIV-Infected Infants

The relation of HIV-1 infection to infant growth and neurodevelopment was studied prospectively in a cohort of 65 infants born to women at risk for HIV infection. No differences were observed at birth between infected infants (INF) and uninfected infants (SR) of HIV-infected women, and infants of uninfected women (SN) with similar socioeconomic background and exposure to drugs. However, postnatal linear growth and cognitive–motor development of INF infants were impaired when compared to SR and SN infants. Declines in linear growth were observed within the first 6 months of life, whereas delays in neurodevelopment were first appreciated at 12 months. In INF infants, decreased linear growth was positively correlated with developmental delay. Moreover, growth and development were both correlated with HIV viral load. INF infants with high plasma HIV RNA copies (>5 × 105/ml) at 6 months of life were more likely to exhibit severe growth and developmental delay than infants with a lower viral burden. The implications of these findings with respect to the mechanism of action of HIV-related growth and neurodevelopmental impairments are discussed.