Rosangela Rodrigues

Discordances between Interpretation Algorithms for Genotypic Resistance to Protease and Reverse Transcriptase Inhibitors of Human Immunodeficiency Virus Are Subtype Dependent

ABSTRACT The major limitation of drug resistance genotyping for human immunodeficiency virus remains the interpretation of the results. We evaluated the concordance in predicting therapy response between four different interpretation algorithms (Rega 6.3, HIVDB-08/04, ANRS [07/04], and VGI 8.0). Sequences were gathered through a worldwide effort to establish a database of non-B subtype sequences, and demographic and clinical information about the patients was gathered. The most concordant results were found for nonnucleoside reverse transcriptase (RT) inhibitors (93%), followed by protease inhibitors (84%) and nucleoside RT inhibitor (NRTIs) (76%). For therapy-naive patients, for nelfinavir, especially for subtypes C and G, the discordances were driven mainly by the protease (PRO) mutational pattern 82I/V + 63P + 36I/V for subtype C and 82I + 63P + 36I + 20I for subtype G. Subtype F displayed more discordances for ritonavir in untreated patients due to the combined presence of PRO 20R and 10I/V. In therapy-experienced patients, subtype G displayed a lot of discordances for saquinavir and indinavir due to mutational patterns involving PRO 90 M and 82I. Subtype F had more discordance for nelfinavir attributable to the presence of PRO 88S and 82A + 54V. For the NRTIs lamivudine and emtricitabine, CRF01_AE had more discordances than subtype B due to the presence of RT mutational patterns 65R + 115 M and 118I + 215Y, respectively. Overall, the different algorithms agreed well on the level of resistance scored, but some of the discordances could be attributed to specific (subtype-dependent) combinations of mutations. It is not yet known whether therapy response is subtype dependent, but the advice given to clinicians based on a genotypic interpretation algorithm differs according to the subtype.

Impact of Adherence to Antiretroviral Therapy in HIV-1–Infected Patients at a University Public Service in Brazil

The objective of this study was to assess if a simple evaluation, adherence to antiretroviral therapy, would correlate to clinical and laboratory outcomes. We followed an open cohort of patients from a public teaching hospital AIDS outpatient clinic. Patients were categorized according to adherence as: regular (Reg), optimal, all doses all days, tolerating only irregular timing (+/- 2 hours) of intake; quasi-regular (qReg), those missing up to four doses or 1 full day during a month; irregular (Irreg), all other irregular regimens, and ignored (Ign), those without information. The results from a simple questionnaire were compared to CD4+ cell counts and human immunodeficiency virus type 1 (HIV-1) RNA plasma viremia. One hundred eighty-two HIV-1-infected patients (126 males, 69%; 56 females, 31%) were analyzed. Information on adherence was available for 168 (90%). Reg adherence was reported by 75 (41%) patients, qReg adherence by 35 (19%), and Irreg by 53 (29%) of patients. The main reasons for nonadherence were forgetfulness, intolerance, use of alcohol, and misunderstanding of prescription. A significant increase of CD4+ T-cell counts and absolute gain were only observed among Reg and qReg users (p < 0.001). The median viral RNA load log10 decreases were -1.68, -1.45, -0.9 log, respectively, for Reg, qReg, and Irreg patients (p = 0.043, Kruskal-Wallis). Development of and death from AIDS occurred almost exclusively among those with Ign or Irreg adherence. Previous use of antiretroviral therapy may have had an impact in treatment response. Individuals who were treatment-naive were more likely to be Reg users (41%). Although more refined methods to assess adherence should be implemented when available, the inability to do so should not prevent simple, albeit subjective measurements that also correlate with favorable outcome. Mechanisms to improve adherence should be considered an integral part of antiretroviral therapy.

Molecular characterisation of newly identified HIV-1 infections in Curitiba, Brazil: preponderance of clade C among males with recent infections

As in many areas of Brazil, the AIDS epidemic in Curitiba is relatively stable, but surveillance is important to support public policy. The molecular characteristics of HIV may be instrumental for monitoring epidemic trends. We evaluated plasma HIV-1 RNA (n = 37) from 38 cases presenting with positive serology, who were among 820 consenting volunteers visiting the downtown counselling and serology testing centre. Seroprevalence was 4.6% (CI 95% 3.2-6.3) and the estimated HIV incidence, as defined by the BED assay, was 2.86 persons/years (CI 95% 1.04-4.68). An additional set of contemporaneous, anonymous samples from a local laboratory was also analysed (n = 20). Regions of the HIV-1 polymerase (n = 57) and envelope (n = 34) were evaluated for subtyping, determination of mosaic structure, primary drug resistance mutations (pDRM), envelope V3 loop motifs and amino acid signatures related to viral tropism. HIV-1 clade B was observed in 53% of cases; HIV-1C in 30% and BC mosaics in 14%, with one F genome and one CF mosaic. Clade C infection was associated with recent infections among males (p < 0.03). Stanford surveillance pDRM was observed in 8.8% of sequences, with 7% showing high level resistance to at least one antiretroviral drug. Tropism for CXCR4 co-receptor was predicted in 18% of envelope sequences, which were exclusively among clade B genomes and cases with serological reactivity to chronic infection.

AIDS Incidence and Mortality in a Hospital-Based Cohort of HIV-1–Seropositive Patients Receiving Highly Active Antiretroviral Therapy in São Paulo, Brazil

Brazilian AIDS and HIV-1-seropositive patients have had free access to highly active antiretroviral therapy (HAART) since November 1996. Although secondary data based on official mortality statistics indicate a sharp decrease in AIDS mortality, few if any studies tried to estimate the prognosis for patients with HIV who have been followed from the beginning of the HAART era. An observational study, with retrospective and prospective components, was done in 233 adult HIV-1-infected subjects who were recruited in the last 10 years at the outpatient sector of the Secondary Immunodeficiencies Clinic of the Department of Dermatology, Hospital das Clinicas da FMUSP, Sao Paulo, Brazil. The definition of AIDS followed the guidelines issued by the Centers for Disease Control (CDC) in 1987. One hundred sixty patients were asymptomatic, 46 had AIDS, 24 had AIDS-related complex, and 3 presented with acute infection at study entry. Twenty-nine (18%) of the asymptomatic subjects developed AIDS during follow-up, with 5 (3%) deaths. Among the 46 AIDS cases at entry, 7 (17%) died during follow-up. Thus, a total of 12 people (5.2%) died of AIDS in this cohort over a mean follow-up of 5.2 years and 24 people were lost to follow-up (10.3%). Ninety percent of the survivors were on combined therapy (82% with 3 or more drugs, and 8% with 2 drugs), while 10% were not taking antiretrovirals. People with AIDS at entry were 5 times more likely to die during this period compared to patients who were asymptomatic at entry (p = 0.006). Women showed better outcomes than men, reflecting differences in CD4+ T-cell counts at study entry. All but 1 patient progressed to AIDS during the pre-HAART era (before 1996). In spite of its recent decline, mortality from AIDS-related conditions remains an important public health issue.

Young Pregnant Women Living with HIV/AIDS in Criciuma, Southern Brazil, Are Infected Almost Exclusively with HIV Type 1 Clade C

Southern Brazil has the highest prevalence rate of AIDS in the country and is the only region in the Americas where HIV-1 C prevails. Metropolitan areas and harbor cities have been evaluated, but limited information is available for small towns and specific populations. We studied women attending the obstetric outpatient clinic of Criciuma, State of Santa Catarina in 2007 to evaluate the molecular epidemiology of HIV-1 among pregnant women living with HIV/AIDS. Forty-two cases had partial pol gene sequenced and additional partial gag and/or env genes from nine women. HIV subtyping was evaluated by phylogenetic methods and antiretroviral (ARV) drug resistance mutations (DRMs) at the Stanford Database. DRMs to one or more ARV class was observed in 20/42, 48% of cases, with 15/41, 37% with viral load <500 copies/ml. Subtype C at pol was identified in 33/42, 78.6% (95% CI: 64-89%), C mosaics (CB, CF) in 2, 4.8% (95% CI: 0.8-19%), F in 4, 9.5% (95% CI: 3-21%), and B in 3, 7.1% (95% CI: 1.8-18%). Discordance in concatenated gag/pol/env or intraregion mosaic was observed in 1/9, 11% of HIV-1 C genomes. The proportion of HIV-1 C in this study is the highest rate described in the Americas. Molecular surveillance in specific populations is instrumental for a better understanding of the Brazilian HIV epidemic.

Southern Brazil HIV type 1 C expansion into the state of São Paulo, Brazil.

Abstract HIV diversity reflects multifactorial evolutionary forces, but monitoring subtype prevalence may provide clues to understanding the epidemic. In the Americas HIV-1 C is present at significant levels only in the southern states of Brazil. We describe in this study the presence of the HIV-1 C pol genome in 11.6% (95 CI 6-21%) of antiretroviral-naive individuals from São Paulo, the major city of South America, and 6.8% (95 CI 4-12%) from the second metropolitan area of the State of São Paulo, Brazil. Moreover, a significant growth trend of this subtype was documented among cases failing therapy in the area. Sequences were obtained by direct nested PCR from cDNA retrotranscribed from plasma RNA. Phylogenetic and amino acid signatures support an expansion from variants previously identified in southern Brazil. The evaluation of additional genomic regions (partial gag, envelope, and/or integrase) in samples with HIV-1 C at pol showed extensive recombination with clade B, observed in 47% of ARV-naive cases. The spread of HIV-1 C locally and to other areas of South America should be monitored as it may influence the dynamics of the epidemic.

CD4+ T-Cell Recovery and Clinical Outcome in HIV-1-Infected Patients Exposed to Multiple Antiretroviral Regimens: Partial Control of Viremia Is Associated with Favorable Outcome

The goal of antiretroviral therapy is clinical benefit through the suppression of viral replication and the immunologic reconstitution of HIV-1-infected patients. In spite of the availability of different highly active antiretroviral therapy only some patients sustain undetectable plasma viremia. We performed an observational study from October 1987 to February 2001 on immunologic and clinical outcome of 148 HIV-1-infected patients from an open clinical cohort at São Paulo University, Brazil. The median T CD4+ at starting first monitored regimen was 227 cells per microliter, with 65% of patients previously exposed to antiretroviral regimens, mostly dual therapy. Virologic response to antiretroviral therapy, after a median period of 179 weeks of monitored treatment, allowed classifying patients as aviremic (RNA plasma viremia below 500 copies per milliliter); viremic (current viral load at historic levels), and viremic-attenuated groups (detectable viremia, but > 1 log viral suppression). HIV RNA viral load, T CD4+ cells count, HIV-1 pol sequencing, inflammatory parameters, and clinical events were documented during a median follow-up of 251 weeks. This study observed better clinical and immunologic responses in the aviremic group, but the viremic-attenuated group showed a significant gain in CD4+ cells (p < 0.013) and a decreased number of cases progressing to an AIDS-defining clinical condition (p < 0.001) compared to the viremic group.

Antiretroviral resistance mutations in human immunodeficiency virus type 1 infected patients enrolled in genotype testing at the Central Public Health Laboratory, São Paulo, Brazil: preliminary results

Antiretroviral resistance mutations (ARM) are one of the major obstacles for pharmacological human immunodeficiency virus (HIV) suppression. Plasma HIV-1 RNA from 306 patients on antiretroviral therapy with virological failure was analyzed, most of them (60%) exposed to three or more regimens, and 28% of them have started therapy before 1997. The most common regimens in use at the time of genotype testing were AZT/3TC/nelfinavir, 3TC/D4T/nelfinavir and AZT/3TC/efavirenz. The majority of ARM occurred at protease (PR) gene at residue L90 (41%) and V82 (25%); at reverse transcriptase (RT) gene, mutations at residue M184 (V/I) were observed in 64%. One or more thymidine analogue mutations were detected in 73%. The number of ARM at PR gene increased from a mean of four mutations per patient who showed virological failure at the first ARV regimens to six mutations per patient exposed to six or more regimens; similar trend in RT was also observed. No differences in ARM at principal codon to the three drug classes for HIV-1 clades B or F were observed, but some polymorphisms in secondary codons showed significant differences. Strategies to improve the cost effectiveness of drug therapy and to optimize the sequencing and the rescue therapy are the major health priorities.

Transmitted Drug Resistance among People Living with HIV/Aids at Major Cities of Sao Paulo State, Brazil

Human immunodeficiency virus type 1 (HIV-1) transmitted drug resistance (TDR) is an important public health issue. In Brazil, low to intermediate resistance levels have been described. We assessed 225 HIV-1 infected, antiretroviral naïve individuals, from HIV Reference Centers at two major metropolitan areas of Sao Paulo (Sao Paulo and Campinas), the state that concentrates most of the Brazilian Aids cases. TDR was analyzed by Stanford Calibrated Population Resistance criteria (CPR), and mutations were observed in 17 individuals (7.6%, 95% CI: 4.5%–11.9%). Seventy-six percent of genomes (13/17) with TDR carried a nonnucleoside reverse transcriptase inhibitor (NNRTI) resistance mutation, mostly K103N/S (9/13, 69%), potentially compromising the preferential first-line therapy suggested by the Brazilian HIV Treatment Guideline that recommends efavirenz-based combinations. Moreover, 6/17 (35%) had multiple mutations associated with resistance to one or more classes. HIV-1 B was the prevalent subtype (80%); other subtypes include HIV-1 F and C, mosaics BC, BF, and single cases of subtype A1 and CRF02_AG. The HIV Reference Center of Campinas presented more cases with TDR, with a significant association of TDR with clade B infection (P < 0.05).

High frequency of BF mosaic genomes among HIV-1-infected children from Sao Paulo, Brazil

HIV-1 genetic diversity information from a pediatric population is scarce. This study enrolled 128 children living with HIV/AIDS, 103 antiretroviral-treated and 25 naive, from the Sao Paulo metropolitan area. Gag, pol and env regions were amplified, and drug resistance mutations, V3 loop, tropism and viral clades were evaluated. Drug resistance mutations among naïve children infected by vertical transmission were uncommon (4.2%), whereas most ARV-experienced children showed extensive mutation patterns. Clade B predominated at the pol region, but the analysis of the three regions concatenated showed 28% with BF mosaic structures. The most common V3 motif was GPGR, followed by GWGR in clade B samples and GPGQ in clade F samples. A predicted X4 phenotype was observed in 27%, without correlation to HIV clade. These findings expand the limited information on molecular characteristics of HIV-1 among children living with HIV/AIDS in the area and may provide information useful for monitoring the epidemic.