Ana Maria Barral de Martinez

HIV-1 subtype C dissemination in southern Brazil

Objectives:To describe the molecular and epidemiological profile of HIV-1 in patients followed at the University Hospital of Rio Grande, Brazil. Design and methods:A cross-sectional study was conducted from September to December 2002. Plasma viral RNA of 85 patients was extracted and protease and reverse transcriptase genes were polymerase chain reaction-amplified and sequenced. Sequences were subtyped and examined to antiretroviral resistance mutations. Laboratory data and past history of antiretroviral treatment were also collected. Results:Most viruses were either subtype B (42%) or subtype C (45%). No risk behaviour, sexual orientation or laboratory parameter was associated with any specific subtype, but subtype C tended to be more frequently found in women (P = 0.06). The prevalence of subtype C has increased over the HIV/AIDS epidemic, accounting for almost 60% of cases diagnosed in 2002. Intra-subtype genetic distances were smaller in subtype C than in subtype B, suggesting a more recent introduction of the former in the epidemic. Of patients under treatment, 60% had at least one antiretroviral drug resistance mutation, but no mutation was specifically associated with any HIV-1 subtype. Only one resistance mutation each was found in drug-naive patients with subtypes B and C. Conclusion:Despite the fact that subtype C appeared in southern Brazil more recently than subtype B, it is now the predominant strain in Rio Grande. The epidemic spread of subtype C could be taking place in Brazil, and possibly in south America, a phenomenon similar to that seen in other countries where this subtype is now totally dominant.

Epidemiologic and evolutionary trends of HIV-1 CRF31_BC-related strains in southern Brazil.

Background:To evaluate the impact of HIV-1 CRF31_BC in the southern Brazilian HIV epidemic. Methods:Blood plasma from 284 patients was collected from July 2002 to January 2003 at 2 reference HIV/AIDS centers in southern Brazil. Viral protease and reverse transcriptase (RT) genomic regions were amplified by RT polymerase chain reaction, sequenced, and subtyped. Evolutionary analyses were performed to estimate the CRF31_BC most recent common ancestor and its population growth rate with BEAST version 1.3. Results:CRF31_BC was responsible for 7.4% of infections. The average time of HIV diagnosis and the proportion of patients on antiretroviral treatment were shorter for CRF31_BC and subtype C than for subtype B. CRF31_BC was found as early as in 1990 in the Brazilian epidemic. Evolutionary analysis of CRF31_BC revealed that it appeared immediately after the introduction of subtype C in Brazil and has been growing at a similar rate as subtype C. Conclusions:CRF31_BC plays an important role in the HIV epidemic of southern Brazil, and its prevalence has increased throughout the years. This circulating recombinant form corresponds to approximately 25% of total HIV isolates in this region in 2004. Understanding the cause of this spread is important for public health strategies in Brazil and in Latin America.

HIV-1 vertical transmission in Rio Grande, Southern Brazil.

The aim of this study was to determine the rate and risk factors of HIV-1 mother-to-child transmission (MTCT), the timing of transmission and the transmitted subtype in a population where subtypes B and C co-circulate. One hundred and forty-four babies born to HIV-1-infected mothers were studied. Subtype and timing of transmission were determined by a nested polymerase chain reaction of the gp41 gene. Seven children were infected (4.9%): four were infected intrautero and one intrapartum. The higher frequency of intrautero transmission was statistically significant (P = 0.001). Use of antiretrovirals (ARVs) in the three stages of gestation was a protective risk factor for MTCT (PR = 0.42; CI: 0.21–0.83; P = 0.013). A higher HIV viral load at delivery was the only independent risk factor for MTCT. Early and universal access to ARVs during pregnancy are the most important measures to decrease vertical HIV-1 transmission even in areas where HIV clade distribution differs.

Determinants of HIV-1 mother-to-child transmission in Southern Brazil

Different human immunodeficiency virus type 1 (HIV-1) subtypes may have distinct biological, immunological and pathogenic properties. Efficiency of mother-to-child transmission (MTCT) may be among those properties, but few and controversial results have been described so far. In this study, 102 children born from HIV-1-infected mothers between 1998 and 2004 in the city of Rio Grande, Brazil were analyzed for potential risk factors associated with MTCT. That geographic region is characterized by a high proportion of subtype C-infected subjects, and it allowed comparison between subtypes B and C and their influence on MTCT. The analysis also included clinical, obstetric and immunological parameters. Multivariate regression analyses were conducted to evaluate the influence of the parameters on MTCT, and prevalence ratios (PR) and 95% confidence intervals (CI95) were also calculated. A surprisingly high prevalence of subtype C of over 70% was found. Only the HIV viral load and the use of ACTG 076 protocol were predictive of MTCT. HIV subtype and CD4 T-cell counts were not associated with increased risk of transmission. Although a clear expansion of subtype C is evident in southern Brazil, it does not seem to correlate with increased risk of vertical transmission.

Prevalência e fatores associados às manifestações bucais em pacientes HIV positivos atendidos em cidade sul-brasileira

The aim of the study was to assess the prevalence of oral lesions in AIDS patients and identify associated factors. A cross-sectional study collected data from interviews, clinical examination, and a review of medical records for adult patients treated at the HIV/AIDS clinic in the University Hospital of the Federal University in Rio Grande, Rio Grande do Sul State, Brazil, focusing on socio-demographic, immune status, and treatment factors. Poisson regression was used in a hierarchical analytical model. From April 2006 to January 2007, 300 patients were observed (51% males; mean age 40 years). Of the total, 39% presented oral lesions, with candidiasis as the most frequent (59.1%), followed by hairy leukoplakia (19.5%). Women showed a lower risk of oral lesions, and there was an inverse association with CD4 count. Increased risk was associated with lower schooling, low income, smoking, alcohol addiction, time since HIV seroconversion, and higher viral load. The data confirm the increased prevalence of opportunistic oral lesions and show their relationship to socioeconomic conditions and modifiable habits and customs.O objetivo deste estudo foi avaliar a prevalencia de lesoes bucais entre pacientes HIV positivos e identificar fatores associados a tais lesoes. Foi realizado estudo transversal que coletou dados mediante entrevista, exame clinico e consulta aos prontuarios medicos de pacientes adultos atendidos no Servico de HIV-AIDS do Hospital Universitario da Universidade Federal do Rio Grande, Rio Grande do Sul, Brasil, sendo considerados fatores socio-demograficos, imunologicos e terapeuticos. Foi utilizada a regressao de Poisson num modelo hierarquico de analise. Entre abril de 2006 a janeiro de 2007 foram observados 300 pacientes, sendo 51% do sexo masculino e media de idade de 40 anos; 39% apresentaram lesoes bucais, sendo a candidiase a mais frequente (59,1%), seguida de leucoplasia pilosa (19,5%). As mulheres apresentaram um risco menor, com observância de uma associacao inversa com o CD4. Houve um risco maior entre aqueles pacientes com menor escolaridade, menor renda, tabagistas, dependentes do alcool, com maior tempo de infeccao pelo HIV e carga viral mais elevada. Os dados confirmaram a elevada prevalencia das manifestacoes bucais oportunistas e evidenciaram a sua relacao com a situacao social, assim como sua relacao com determinados habitos e costumes passiveis de modificacao.

Alta prevalência de usuários que não retornam ao Centro de Testagem e Aconselhamento (CTA) para o conhecimento do seu status sorológico: Rio Grande, RS, Brasil

The Testing and Counseling Centers are important sources of epidemiological information. This study describes a research conducted with the users of the Testing and Counseling Center of Rio Grande-RS submitted to anti-HIV test during the period 2001-2004. Demographic and behavioral factors of individuals attended in the service were analyzed using the database SISCTA-2002/RG. HIV-1 seropositivity between 2001 and 2004 was of 1,1%; 2,4%; 2,3% and 1,7%, respectively. In 2003 and 2004, 37,7% and 36% of the HIV-1 positive patients did not return to the Testing and Counseling Center for getting the result of their serological anti-HIV or confirmatory tests. These results seem to reflect some tendencies of the HIV epidemic in Rio Grande and in Brazil. It is important to emphasize the high percentage of HIV-1 positive patients who do not return for getting the result of their test. In terms of public health this risk behavior may jeopardize the efforts for controlling the epidemic.

Fatores de risco e prevalência da infecção pelo HPV em pacientes de Unidades Básicas de Saúde e de um Hospital Universitário do Sul do Brasil

PURPOSE To determine the HPV prevalence and genotypes and to identify factors associated with infection in pregnant and non-pregnant women with positive or negative HIV-1, treated in Gynecology and Obstetrics Ambulatories and in Health Primary Units, in Rio Grande, Rio Grande do Sul State, Brazil. METHODS Cervical cells samples from 302 patients were analyzed for HPV presence and genotypes were determined by nested and sequencing polymerase chain reaction. We calculated prevalence ratios associated with the studied variables by Fishers exact or χ² tests, and Poissons regression. Women with insufficient material were excluded from the study. RESULTS HPV was detected in 55 of the 302 women included in the study (18.2%); of these, 31 were pregnant, showing a significant association for HPV (p=0.04) when compared to non-pregnant ones. Risk factors for the infection were: patients aged <20 years-old (p=0.04), early initiation of sexual life (p=0.04), absence of cytological test (p=0.01), diagnosis of altered cytology (p=0.001), and counting <349 cells/mm³ (p=0.05). However, multi-parity was found to be a protective factor for the infection (p=0.01). Multivariate analysis showed that age <20 years-old (PR=2.8; 95%CI 1.0 - 7.7, p=0.04) and an altered cytological result (PR=11.1; 95%CI 3.0 - 4.1, p=0.001) were significantly associated with infection. HPV genotype was determined in 47 samples (85.4%) presenting one genotype per infection: eight HPV 16 and 58; six HPV 6; four HPV 18 and 33; three HPV 53 and 82; two HPV 83 and 61; one HPV 31, 35, 45, 64, 68, 71 and 85. CONCLUSIONS The prevalence of HPV detection was 18.2%, the most frequent genotypes were 16 and 58, and sociodemographic and gynecological factors were associated with viral infection.

Isoenzyme profile as parameter to differentiate pathogenic strains of Entamoeba histolytica in Brazil

The isoenzyme profiles (IP) of 33 strains of Entamoeba histolytica isolated from patients and carriers of two regions in Brazil (Amazonia and Southeast) were determined. The enzymes phosphoglucomutase, glucose-phosphate isomerase, hexokinase and malic enzyme were considered. IP of the strains was correlated with culture conditions, time of maintenance in laboratory and clinical history of patients. The strains were maintained under polyxenic, monoxenic and axenic culture conditions: 27 polyxenic, 1 polyxenic and monoxenic, 1 polyxenic, monoxenic and axenic and 4 axenic only. The patients were symptomatic and asymptomatic. The symptomatic patients presented either non dysenteric (NDC) or dysenteric colitis (DC), associated or not with hepatic abscess (HA). One patient presented anal amoeboma (AM). The analysis of IP for isolates maintained in polyxenic culture showed non pathogenic IP (I) for strains from carriers and patients with NDC, while the strains isolated from patients presenting DC, HA and AM resulted in isolates II or XIX pathogenic IP. This parameter was not able to differentiate strains from carriers from symptomatic patients when these strains were found in axenic or monoxenic culture. All these strains displayed pathogenic IP (II), demonstrating the inability of this parameter to classifying for virulence since it showed identical IP for strains isolated from carriers or symptomatic patients.

Primary HIV-1 drug resistance in the C-terminal domains of viral reverse transcriptase among drug-naïve patients from Southern Brazil

BACKGROUND Major and accessory drug resistance mutations have been recently characterized in the C-terminal RT subdomains of HIV-1, connection and RNase H. However, their presence in treatment-naïve patients infected with HIV-1 non-B subtypes remains largely unknown. OBJECTIVES To characterize the patterns of primary resistance at the C-terminal RT subdomains of HIV-1 infecting subjects in the southern region of Brazil, where HIV-1 subtypes B and C co-circulate. STUDY DESIGN Plasma viral RNA was extracted from patients recently diagnosed for HIV infection (2005-2008). The protease and reverse transcriptase regions were PCR-amplified and sequenced. Infecting HIV subtypes were assigned by phylogenetic inference and drug resistance mutations were determined following the IAS consensus and recent reports on C-terminal RT mutations. RESULTS The major mutation to NNRTI T369I/V was found in 1.8% of patients, while A376S was present in another 8.3%. In the RNase H domain, the compensatory mutation D488E was more frequently observed in subtype C than in subtype B (p=0.038), while the inverse was observed for mutation Q547K (p<0.001). The calculated codon genetic barrier showed that 22% of subtype B isolates, but no subtype C, carried T360, requiring two transitions to change into the resistance mutation 360V. CONCLUSIONS Major resistance-conferring mutations to NNRTI were detected in 10% of RT connection domain viral sequences from treatment-naïve subjects. We showed for the first time that the presence of specific polymorphisms can constrain the acquisition of definite resistance mutations in the connection and RNase H subdomains of HIV-1 RT.

Papilomavírus humano: prevalência e genótipos encontrados em mulheres HIV positivas e negativas, em um centro de referência no extremo Sul do Brasil

INTRODUCTION The aim of this study was detect the presence of human papillomavirus and investigate the prevalence and distribution of the HPV-6, 11, 16 and 18 genotypes among HIV-1 positive and negative women. METHODS Samples of cervical smears from 98 women were analyzed using the nested polymerase chain reaction for the presence of HPV and using the type-specific technique for genotype detection. Genotypes were confirmed by means of restriction fragment analysis. The chi-square and Fisher tests were performed for the statistical analysis. RESULTS HPV-DNA was observed in 66.3% of the samples analyzed: 76.4% in the HIV-positive group and 60% in the HIV-negative group (p = 0.1). Higher prevalence of viral infection due to oncogenic genotypes was observed in the HIV-positive group (65.2%) than in the HIV-negative group (28.6%), (p = 0.006), and HPV-16 was the most frequent in the two groups, followed by HPV-18. CONCLUSIONS It is suggested that HIV-positive women present a higher likelihood of infection by oncogenic HPV genotypes, and the importance of a screening and differential diagnosis program for this group is highlighted.