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1.
BACKGROUND: The HIV Network for Prevention Trials (HIVNET) 012 trial showed that NVP resistance (NVPR) emerged in some women and children after the administration of single-dose nevirapine (SD-NVP). We tested whether K103N-containing human immunodeficiency virus (HIV)-1 variants persisted in women and infants 1 year or more after the administration of SD-NVP. METHODS: We analyzed samples from 9 women and 5 infants in HIVNET 012 who had NVPR 6-8 weeks after the administration of SD-NVP. Samples were analyzed with the ViroSeq system and with 2 sensitive resistance assays, LigAmp and TyHRT. RESULTS: ViroSeq detected the K103N mutation in 8 of 9 women and in 2 of 5 infants. LigAmp detected the K103N mutation at low levels in 8 of 9 women and in 4 of 5 infants. K103N was not detected by ViroSeq 12-24 months after the administration of SD-NVP but was detected by LigAmp in 3 of 9 women and in 1 of 5 infants. K103N was also detected in those samples by use of the TyHRT assay. CONCLUSIONS: K103N-containing variants persist in some women and infants for 1 year or more after the administration of SD-NVP. Sensitive resistance assays may provide new insight into the impact of antiretroviral drug exposure on HIV-1 evolution.  相似文献   

2.
In Uganda, the HIV Network for Prevention Trials (HIVNET) 012 study recently demonstrated that single-dose nevirapine (Nvp) prophylaxis is effective for preventing mother-to-child transmission (MTCT) of human immunodeficiency virus type 1 (HIV-1). This exploratory study examines the relationship between HIV-1 subtype, MTCT, and the development of Nvp resistance (Nvp(R)) in women enrolled in HIVNET 012. For 102 women (32 whose infants were HIV-1 infected by age 6-8 weeks and 70 whose infants were uninfected), HIV-1 subtypes included 50 (49%) subtype A, 35 (34%) subtype D, 4 (4%) subtype C, 12 (12%) recombinant subtype, and 1 unclassified. There was no apparent difference in the rate of MTCT among women with subtype A versus D (adjusted odds ratio [OR], 1.24; 95% confidence interval [CI], 0.45-3.43). Nvp(R) mutations were detected more frequently at 6-8 weeks postpartum in women with subtype D than in women with subtype A (adjusted OR, 4.94; 95% CI, 1.21-20.22). Additional studies are needed to further define the relationship between HIV-1 subtype and Nvp(R) among women receiving Nvp prophylaxis.  相似文献   

3.
We compared nevirapine (NVP) resistance (NVPR) mutations in maternal plasma 7 days vs. 6-8 weeks after single-dose NVP prophylaxis. In the HIVNET 012 trial, Ugandan women received a single dose of NVP in labor for prevention of HIV-1 mother-to-child transmission. NVPR mutations were detected in 70 (25%) of 279 women 6-8 weeks after NVP. Samples collected 7 days after NVP were analyzed from a subset of those 279 women. Genotyping was performed with the ViroSeq HIV-1 Genotyping System. NVPR was analyzed using paired samples from 7 days and 6-8 weeks after NVP. Sixty-five women had genotyping results obtained for samples collected at both 7 days and 6-8 weeks post-NVP. Twenty-one (32%) of those women had NVPR mutations detected in one or both samples. This included three women with NVPR at 7 days only, seven with NVPR at 6-8 weeks only, and 11 with NVPR at both time points. Eight women had >1 NVPR mutation detected 7 days after NVP. Y181C was the most common NVPR mutation detected at 7 days, whereas K103N was the most common NVPR mutation detected at 6-8 weeks. We conclude that NVPR may be detected in women as early as 7 days after single-dose NVP. Complex patterns of NVPR are detected in some women. The Y181C NVPR mutation often fades from detection by 6-8 weeks. In contrast, the K103N mutation emerges more slowly, but often remains detectable 6-8 weeks after NVP.  相似文献   

4.
The HIVNET 012 trial in Uganda demonstrated that a regimen of single-dose nevirapine (NVP) can prevent HIV-1 mother-to-child transmission. Previous studies show that HIV-1 with one or more NVP resistance (NVPR) mutations can be selected in many women as early as 7 days after single-dose NVP. We evaluated the genetic linkage of NVPR mutations in plasma from women in HIVNET 012 collected 7 days after single-dose NVP administration. The HIV-1 pol region was amplified and cloned from 20 plasma samples (16 with NVPR mutations detected by population sequencing and 4 with no NVPR mutations detected), and 10 clones from each sample were sequenced. Up to five different NVPR mutations were detected in clones from a single sample. K103N and Y181C were the most common mutations detected. Clones with two genetically linked mutations were detected in four samples. Different combinations of NVPR mutations were linked in individual clones, but none of the clones contained both K103N and Y181C. Further studies are needed to evaluate whether selection of minority variants with one or more NVPR mutations after single-dose NVP is clinically relevant.  相似文献   

5.
The prevalence of human immunodeficiency virus (HIV)-1-infected cells and HIV-1 RNA levels in genital secretions and breast milk and the risk of mother-to-child transmission of HIV-1 were compared among subtypes A, C, and D in a Kenyan cohort. Pregnant women infected with subtype C were significantly more likely to shed HIV-1-infected vaginal cells than were those infected with subtype A or D (odds ratio [OR], 3.6 [95% confidence interval {CI}, 1.4-8.8]; P = .006). This relationship held after adjusting for age, CD4 cell count, and plasma HIV-1 RNA load (OR, 3.1 [95% CI, 1.1-8.6]; P = .03). These observations suggest that HIV-1 subtype influences mucosal shedding of HIV-1.  相似文献   

6.
OBJECTIVE: To examine the emergence and fading of NVP resistance (NVP(R)) mutations in HIV-1-infected Ugandan women and infants who received single dose NVP to prevent HIV-1 vertical transmission. DESIGN: We examined NVP(R) in women and infants who received NVP in the HIVNET 012 clinical trial, including 41 out of 48 women with infected infants, 70 randomly-selected women with uninfected infants, and 33 out of 49 infected infants. METHODS: Plasma HIV-1 was analyzed using the Applied Biosystems ViroSeq HIV-1 Genotyping System. RESULTS: NVP(R) mutations were detected in 21 out of 111 (19%) women tested 6-8 weeks after delivery. The rate of NVP(R) was similar among women whose infants were or were not HIV-1 infected. K103N was the most common mutation detected. NVP(R) mutations faded from detection within 12-24 months in all 11 evaluable women. High baseline viral load and low baseline CD4 cell count were associated with development of NVP(R). NVP(R) mutations were detected in 11 out of 24 (46%) evaluable infants who were infected by 6-8 weeks of age. The most common NVP(R) mutation detected in infants was Y181C. Those mutations faded from detection by 12 months of age in all seven evaluable infants. Of nine evaluable infants with late HIV-1 infection, only one had evidence of NVP(R). CONCLUSIONS: NVP(R) was detected more frequently in infants than women following NVP prophylaxis, and different patterns of NVP(R) mutations were detected in women versus infants. NVP(R) was detected infrequently in infants with late HIV-1 infection. NVP-resistant HIV-1 faded from detection in women and infants over time.  相似文献   

7.
The administration of single-dose nevirapine to women in labor and their infants can prevent HIV-1 mother-to-child transmission. We examined nevirapine resistance in infants who were HIV-1 infected despite single-dose nevirapine prophylaxis, including 18 Ugandan infants (HIVNET 012 trial, nine subtype A and nine subtype D) and 23 Malawian infants (NVAZ trial, all subtype C). Nevirapine resistance was more frequent in infants with subtype C than with subtypes A and D (87 versus 50%, P = 0.016).  相似文献   

8.
We analyzed the development of nevirapine (NVP) resistance in human immunodeficiency virus type 1 (HIV-1)-infected Malawian infants who received regimens containing single-dose NVP (SD-NVP) for the prevention of mother-to-child transmission (MTCT) of HIV-1. All infants received SD-NVP, and some randomly received zidovudine (ZDV) as well. Mothers did or did not receive SD-NVP on the basis of when they arrived at the hospital for delivery. In infants 6-8 weeks of age, NVP resistance was less frequent when infants had received SD-NVP plus ZDV and mothers had not received SD-NVP than when infants had received SD-NVP alone and mothers had received SD-NVP (4/15 [27%] vs. 20/23 [87%]; P < .001). The risk of MTCT of HIV-1 was comparable with these regimens. Infant-only prophylaxis also eliminates the development of NVP resistance in mothers.  相似文献   

9.
K103N is frequently detected in HIV-infected women after single dose (SD) nevirapine (NVP). K103N-containing variants were detected more frequently by the ViroSeq HIV-1 Genotyping System in women with subtype C (69.2%) than subtypes A (19.4%, p < 0.0001) or D (36.1%, p < 0.0001). K103N-containing variants were also detected more frequently and at higher levels in women with subtype C by the LigAmp assay. In this report, we analyzed samples collected prior to or within hours after SD NVP administration from antiretroviral drug-naive African women with subtypes A, C, and D. Only 1/254 samples had an NVP resistance mutation detected with the ViroSeq system, and only 4/236 samples had K103N detected at < 0.5% with the LigAmp assay [2/110 (1.8%) with subtype A, 1/46 (2.2%) with subtype C, and 1/80 (1.3%) with subtype D] (p = 0.92). We did not detect significant differences in the pre-NVP frequency of NVP resistance mutations or the pre-NVP levels of K103N-containing variants in women with subtypes A, C, and D that explain the dramatic subtype-based differences in emergence of HIV-1 variants with these mutations after SD NVP exposure.  相似文献   

10.
11.
The frequency of resistance mutations was estimated in the cohort of Agence Nationale de Recherches sur le SIDA Ditrame Plus, a study that evaluated the combination of short-course zidovudine (ZDV) plus lamivudine (3TC) and single-dose nevirapine (SD-NVP) followed by 3 days of postpartum ZDV plus 3TC for the prevention of mother-to-child transmission of human immunodeficiency virus type 1 (HIV-1). The frequency with which resistance mutations were detected in mothers at week 4 postpartum was 1.14% (95% confidence interval [CI], 0.03%-6.17%) for NVP and 8.33% (95% CI, 3.66%-15.76%) for 3TC. In multivariate analysis, 3TC resistance was associated with a longer duration of ZDV plus 3TC prepartum prophylaxis (P=.009). This regimen, which is feasible in resource-limited settings, prevents most peripartum HIV-1 transmission and minimizes the development of NVP resistance.  相似文献   

12.
OBJECTIVES: Use of single dose nevirapine (SD NVP) for prevention of HIV-1 mother-to-child transmission (pMTCT) is associated with selection of K103N-containing HIV variants. Repeat use of SD NVP for pMTCT may influence emergence and persistence of NVP-resistant variants. DESIGN: K103N-containing variants were studied in 48 Ugandan women who received SD NVP in the HIVNET 012 trial, and were re-exposed to SD NVP in one (n = 44) or two (n = 4) subsequent pregnancies during a 5-year follow-up study. METHODS: Samples were analyzed using the LigAmp assay (assay cutoff: 0.5% K103N). RESULTS: Among 44 women who were re-exposed to SD NVP in one subsequent pregnancy, 37.8% had K103N detected within 1 year of SD-NVP re-exposure. Detection of K103N was independently associated with detection of K103N 6-8 weeks after the first SD NVP exposure and with pre-NVP viral load. The portion of women with undetectable K103N by 2 years after SD NVP administration was similar after first versus second use of SD NVP for pMTCT. K103N was undetectable in 93.2% of evaluable women by 3 years of re-exposure. Only two of four women who received SD NVP in two pregnancies during the follow-up study had K103N detected after the last SD NVP exposure. CONCLUSIONS: K103N was detected in some women within 1 year of SD NVP re-exposure, but faded from detection in most women by 3 years after re-exposure. Detection of K103N by 1 year after SD NVP re-exposure was associated with prior selection of K103N-containing variants and with pre-NVP viral load.  相似文献   

13.
OBJECTIVE: To compare compliance and infant HIV-1 infection risk at 6 weeks with the Thai-CDC and HIVNET-012 antiretroviral regimens in a field setting. DESIGN: Randomized clinical trial. SETTING: Tertiary hospital antenatal clinic in Nairobi, Kenya. PARTICIPANTS: HIV-1 infected women referred from primary care clinics. INTERVENTIONS: Thai-CDC zidovudine regimen or HIVNET-012 nevirapine regimen. MAIN OUTCOME MEASURES: Women were considered compliant if they used >or= 80% of the doses. Infants were tested for HIV-1 at 6 weeks.RESULTS Seventy women were randomized to Thai-CDC and 69 to HIVNET-012 regimens. More women were compliant with the antenatal (86%) than the intrapartum (44%) Thai-CDC regimen doses ( P= 0.001). Ninety-seven per cent took the maternal and 91% gave the infant dose of the HIVNET-012 regimen (P = 0.2). Overall, 41% were compliant with the Thai-CDC regimen and 87% with the HIVNET-012 regimen ( P< 0.001). Compliance with the Thai-CDC regimen was associated with partner support of antiretroviral use [odds ratio (OR), 3.0;, 95% confidence interval (CI), 1.0-9.1] and knowledge at recruitment that antiretroviral drugs could prevent infant HIV-1 (OR, 2.9; 95% CI, 1.0-8.1). Compliance with the HIVNET-012 regimen was associated with partner notification (OR, 8.0; 95% CI, 1.5-50) and partner willingness to have HIV-1 testing (OR, 7.5; 95% CI, 1.4-40). There was a trend for a higher risk of transmission with the HIVNET-012 regimen than with the Thai-CDC regimen (22% versus 9%; P= 0.07). CONCLUSION: Compliance with the Thai-CDC and HIVNET-012 regimens was comparable to that in efficacy trials. Partner involvement, support and education on perinatal HIV-1 prevention may improve compliance and increase the number of infants protected from HIV-1 infection.  相似文献   

14.
Conventional sequence analysis detects human immunodeficiency virus (HIV)-1 drug resistance mutations in approximately 40% of women shortly after they receive intrapartum single-dose nevirapine (SD-NVP). Using sensitive real-time polymerase chain reaction assays for the K103N and Y181C resistance mutations, we tested genotyped virus before and after SD-NVP in 50 South African women infected with HIV-1 subtype C. By sequence analysis, 40 women had no detectable resistance mutations, and an additional 6 women were negative for Y181C after SD-NVP. We found K103N in 16 (40%) of 40 women and Y181C in 5 (11%) of 46 women at 6-36 weeks postpartum. Clonal sequencing confirmed K103N in 5 of 5 representative samples and Y181C in 4 of 4 samples. Four of the 5 women with newly identified Y181C also had K103N. These findings indicate that resistance mutations emerged in at least 65% of the women after SD-NVP and emphasize the importance of further research to determine the clinical implications.  相似文献   

15.
OBJECTIVE: Our aim was to study the response to antiretroviral treatment among women exposed to single-dose nevirapine (NVP) and/or short-course zidovudine (ZDV; with or without lamivudine [3TC]) for the prevention of mother-to-child transmission of human immunodeficiency virus (HIV) infection. METHODS: All HIV type 1-infected women who initiated antiretroviral treatment with stavudine or ZDV, 3TC, and NVP or efavirenz were eligible for the MTCT-Plus program in Abidjan, Ivory Coast. Exposed women had received either single-dose NVP alone or short-course ZDV (with or without 3TC) plus single-dose NVP during previous pregnancy. Genotypic resistance testing was performed at week 4 after delivery. Virologic failure was defined as a plasma HIV RNA level >500 copies/mL 12 months after initiation of antiretroviral treatment. RESULTS: Among 247 women who received antiretroviral treatment, 109 (44%) were unexposed; 81 had received short-course ZDV with 3TC, as well as single-dose NVP; 5 had received short-course ZDV plus 3TC; 50 had received short-course ZDV plus single-dose NVP; and 2 had received single-dose NVP alone. No ZDV mutation was detected in the 115 women whose specimens were available for genotypic testing; 11 (15.1%) of 73 women with 3TC exposure who were tested after delivery had 3TC resistance mutations. Three (4.3%) of 69 women exposed to short-course ZDV and 3TC plus single-dose NVP and 16 (38.1%) of 42 women exposed to short-course ZDV plus single-dose NVP had NVP resistance mutations. Antiretroviral treatment was initiated a median of 21 months after the intervention to prevent mother-to-child HIV transmission (median CD4(+) T lymphocyte count, 188 cells/mm(3)). Month 12 virologic failure was identified in 42 (19.2%) of 219 women for whom data were available, and multivariate analysis revealed that it was associated with poor adherence to treatment (adjusted odds ratio [aOR], 12.7; 95% confidence interval [CI], 3.0-53.9), postpartum 3TC resistance mutations (aOR, 6.9; 95% CI, 1.1-42.9), and a baseline CD4(+) T lymphocyte count <200 cells/mm(3) (aOR, 0.3; 95% CI, 0.2-0.8). NVP resistance was not associated with virological failure (aOR, 1.8; 95% CI, 0.5-6.5). CONCLUSIONS: Our study found that poor adherence and 3TC resistance acquired after the intervention to prevent mother-to-child transmission of HIV infection were associated with virologic failure in women who initiated antiretroviral treatment.  相似文献   

16.
BACKGROUND: Single-dose nevirapine (NVP) prophylaxis to mother and infant is widely used in resource-constrained settings for preventing mother-to-child transmission (MTCT) of HIV-1. Where women do not access antenatal care or HIV testing, postexposure prophylaxis to the infant may be an important preventative strategy. METHODS: This multicentre, randomized, open-label clinical trial (October 2000 to September 2002) in South Africa compared single-dose NVP with 6 weeks of zidovudine (ZDV), commenced within 24 h of delivery among 1051 infants whose mothers had no prior antiretroviral therapy. HIV-1 infection rates were ascertained at birth, and at 6 and 12 weeks of age. Kaplan-Meier survival methods were used to estimate HIV-1 infection rates in an intention-to-treat analysis. RESULTS: Overall, 6 week and 12 week MTCT probability was 12.8% [95% confidence interval (CI),10.5-15.0] and 16.3% (95% CI,13.4-19.2), respectively. At 12 weeks, among infants who were not infected at birth, 24 (7.9%) infections occurred in the NVP arm and 41 (13.1%) in the ZDV arm (log rank P = 0.06). Using multivariate analysis, factors associated with infection following birth were ZDV use [odds ratio (OR), 1.8; 95% CI,1.1-3.2; P = 0.032), maternal CD4 cell count < 500 x 10(6) cells/l (OR, 2.5; 95% CI,1.3-5.0; P = 0.007), maternal viral load > 50 000 copies/ml (OR, 3.6; 95% CI,2.0-6.2; P < 0.0001) and breastfeeding (OR, 2.2; 95% CI,1.3-3.8; P = 0.006). CONCLUSION: A single-dose of NVP given to infants offers protection against HIV-1 infection and should be a strategy used in infants of mothers with untreated HIV infection.  相似文献   

17.
18.
Among 1022 adults with either pneumococcal bacteremia or meningitis, 85.5% of women and 74.7% of men were infected with human immunodeficiency virus (HIV). A multivariable regression analysis found more pediatric serogroups/serotypes (odds ratio [OR], 1.59 [95% confidence interval [CI], 1.18-2.15]) and more penicillin-nonsusceptible strains (OR, 1.65 [95% CI, 1.06-2.59]) in women than in men; it was also found that bacteremic women were more likely to be infected with HIV (OR, 1.85 [95% CI, 1.26-2.71]) and to be younger (OR, 1.72 [95% CI, 1.25-2.36]) than were men. Thus, conjugate pneumococcal vaccination of children may reduce, in particular, both antibiotic resistance and the burden of conjugate vaccine serotype pneumococcal disease in young, HIV-infected women.  相似文献   

19.
Hsieh RK  Lim KH  Kuo HT  Tzen CY  Huang MJ 《Chest》2005,128(1):317-321
STUDY OBJECTIVES: The prevalence of epidermal growth factor receptor (EGFR) mutations in gefitinib-naive lung cancer patients is higher in adenocarcinomas, in women, and in Japanese. To further investigate the prevalence of EGFR mutations in relation to ethnic and geographic factors, we evaluated EGFR mutations in a series of Taiwanese patients with primary lung adenocarcinomas who had never been treated with gefitinib. DESIGN AND METHODS: We retrospectively studied 35 primary lung adenocarcinoma samples for mutations in the tyrosine kinase domain of EGFR; exons 18, 19, and 21 were analyzed by nested polymerase chain reaction and automated sequencing. Clinicopathologic information was obtained from patient records and pathology reports. Correlation between EGFR mutations and patient characteristics, including sex, smoking history, and pathologic subtypes, were evaluated by using the chi(2) test and logistic regression analysis. RESULTS: Heterozygous EGFR mutations were detected in 17 of 35 patients (48%). Missense mutations in exon 21 (13 of 17 patients, 76%) were the most frequent mutations detected. EGFR mutations were more frequent in women (13 of 18 patients [72%]) than in men (4 of 17 patients [23%]; p = 0.004), more frequent in nonsmokers (14 of 21 patients [66%]) than in current smokers (3 of 14 patients [21%]; p = 0.009), and when any degree of bronchioloalveolar carcinoma (BAC) was present (14 of 21 patients [66%]) compared with pure adenocarcinoma (3 of 14 patients [21%]; p = 0.009). Logistic regression analysis demonstrated that female gender (odds ratio [OR], 10.913; 95% confidence interval [CI], 1.778 to 66.97; p = 0.01) and BAC, including adenocarcinomas with any bronchioloalveolar features (OR, 9.708; 95% CI, 1.464 to 64.393; p = 0.019), were significantly associated with EGFR mutations. CONCLUSIONS: In our series, female sex and bronchioloalveolar pathologic subtype predicted the presence of EGFR mutations in lung adenocarcinomas, and the high frequency of EGFR mutations supports the hypothesis that genetic backgrounds and/or environmental factors may affect the pathogenesis of certain lung cancers.  相似文献   

20.
BACKGROUND: Human immunodeficiency virus type 1 (HIV-1) subtypes differ in biological characteristics that may affect pathogenicity. METHODS: We determined the HIV-1 subtype-specific rates of disease progression among 350 HIV-1 seroconverters. Subtype, viral load, and CD4(+) cell count were determined. Cox proportional hazards regression modeling was used to estimate adjusted hazard ratios (HRs) of progression to acquired immunodeficiency syndrome (AIDS) (defined as a CD4(+) cell count of < or =250 cells/mm(3)) and to AIDS-associated death. RESULTS: A total of 59.1% of study subjects had subtype D strains, 15.1% had subtype A, 21.1% had intersubtype recombinant subtypes, 4.3% had multiple subtypes, and 0.3% had subtype C. Of the 350 subjects, 129 (37%) progressed to AIDS, and 68 (19.5%) died of AIDS. The median time to AIDS onset was shorter for persons with subtype D (6.5 years), recombinant subtypes (5.6 years), or multiple subtypes (5.8 years), compared with persons with subtype A (8.0 years; P = .022). Relative to subtype A, adjusted HRs of progression to AIDS were 2.13 [95% confidence interval {CI}, 1.10-4.11] for subtype D, 2.16 [95% CI, 1.05-4.45] for recombinant subtypes, and 4.40 [95% CI, 1.71-11.3] for multiple subtypes. The risk of progression to death was significantly higher for subtype D (adjusted HR, 5.65; 95% CI, 1.37-23.4), recombinant subtypes (adjusted HR, 6.70; 95% CI, 1.56-28.8), and multiple subtypes (adjusted HR, 7.67; 95% CI, 1.27-46.3), compared with subtype A. CONCLUSIONS: HIV disease progression is affected by HIV-1 subtype. This finding may impact decisions on when to initiate antiretroviral therapy and may have implications for future trials of HIV-1 vaccines aimed at slowing disease progression.  相似文献   

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