100 research outputs found
Comparison of different culture media and storage temperatures for the long-term preservation of Streptococcus pneumoniae in the tropics
Objective: The preservation of Streptococcus pneumoniae by standard freezing methods for subsequent tests- such as serotyping and antibiotic susceptibility-is not possible or is difficult in many developing countries because of the high cost of equipment, inadequate equipment maintenance, and irregular power supply. We evaluated alternative low-cost methods, by comparing different culture media and storage temperatures. Methods: Clinical isolates of five capsular types (1, 5, 7, 19, and 23) of S. pneumoniae were preserved in rabbit blood, sheep blood, skimmed milk, or glycerol-chocolate broth, and stored at -20 °C or -70 °C. The cultures were also preserved by lyophilization or sand desiccation, followed by storage at room temperature and 4 °C. The viability of the preserved cultures was determined by making serial colony counts on day 0 and after 1 week, 4 weeks, 4 months and 16 months. The viability of cultures preserved by sand desiccation and storage at 4 °C was also determined every 6 months for up to 68 months. Findings: Irrespective of the media used, cultures maintained at -20 °C became nonviable by the fourth month, while those maintained at -70 °C were still viable at 16 months. Cultures preserved by lyophilization or sand desiccation lost their viability by the fourth month when maintained at local room temperature (30-42 °C), but remained viable when stored at 4 °C for up to 68 months. Conclusions: Our results confirm that freezing at -70 °C, or lyophilization and storage at 4 °C are the ideal methods for the preservation of S. pneumoniae. In laboratories where lyophilization is not feasible, sand desiccation and storage at 4 °C offers an alternative low-cost method for the long-term preservation of S. pneumoniae
Meconium Atazanavir Concentrations and Early Language Outcomes in HIV-Exposed, Uninfected Infants with Prenatal Atazanavir Exposure
This is not the published version.OBJECTIVE: To investigate whether prenatal atazanavir (ATV) exposure, assessed by meconium antiretroviral quantification, predicts early child language outcomes. Prenatal ATV exposure previously was associated with poorer language development in one-year-olds. METHODS: Pregnant women with HIV and their uninfected infants enrolled in the SMARTT study. Meconium antiretroviral concentrations were quantified by liquid chromatography-tandem mass spectrometry. Language development at 1 year was assessed with MacArthur-Bates Communicative Development Inventory (CDI) and Bayley Scales of Infant and Toddler Development—Third Edition (Bayley-III). Late language emergence (LLE) was defined as ≥ one of four CDI scores ≤10th percentile for age. Associations between fetal ATV exposure timing and duration, meconium ATV concentration, and language outcomes were evaluated, adjusting for potential confounders. RESULTS: Through 2013, meconium samples were available from 175 of 432 infants with prenatal ATV exposure. Valid Bayley-III (n=93) and CDI (n=106) assessments also were available. After adjustment for potential confounders, higher ATV meconium concentrations were associated with lower LLE risk (P=0.04), and cumulative ATV exposure duration also was associated with higher Bayley-III Language scores (P=0.03). Maternal ATV duration and initiation week correlated with ATV meconium concentrations (positively and negatively, respectively). CONCLUSIONS: Higher meconium ATV concentrations were protective against developmental language delays at 1 year, suggesting the importance of fetal ATV detoxification into meconium. This information supports ATV exposure safety for infant language development. ATV is a preferred ARV for pregnant women with HIV, suggesting the importance of ATV safety investigations. Additionally, further pursuit of the influences on language development in HEU infants is required
Cost-Effectiveness of Pre-exposure HIV Prophylaxis During Pregnancy and Breastfeeding in Sub-Saharan Africa
Antiretroviral pre-exposure prophylaxis (PrEP) for the prevention of HIV acquisition is cost-effective when delivered to those at substantial risk. Despite a high incidence of HIV infection among pregnant and breastfeeding women in sub-Saharan Africa (SSA), a theoretical increased risk of preterm birth on PrEP could outweigh the HIV prevention benefit
Evaluation of Risk for Late Language Emergence after In Utero Antiretroviral Drug Exposure in HIV-exposed Uninfected Infants
This is not the published version.BACKGROUND Combination antiretroviral (cARV) regimens are recommended for pregnant women with HIV to prevent perinatal HIV transmission. Safety is a concern for infants who were HIV-exposed but uninfected (HEU), particularly for neurodevelopmental problems, such as language delays. METHODS We studied late language emergence (LLE) in HEU children enrolled in a US-based prospective cohort study. LLE was defined as a caregiver-reported score ≤ 10th percentile in any of 4 domains of the MacArthur-Bates Communicative Development Inventory for one-year-olds and as ≥1 standard deviation below age-specific norms for the Ages and Stages Questionnaire for two-year-olds. Logistic regression models were used to evaluate associations of in utero cARV exposure with LLE, adjusting for infant, maternal, and environmental characteristics. RESULTS 1,129 language assessments were conducted among 792 one- and two-year-olds (50% male, 62% black, and 37% Hispanic). Overall, 86% had in utero exposure to cARV and 83% to protease inhibitors. LLE was identified in 26% of one-year-olds and 23% of two-year-olds, with higher rates among boys. In adjusted models, LLE was not associated with maternal cARV or ARV drug classes in either age group. Among cARV-exposed one-year-olds, increased odds of LLE was observed for those exposed to atazanavir (aOR=1.83, 95% CI=1.10-3.04), particularly after the first trimester (aOR=3.56, p=0.001), compared to atazanavir-unexposed infants. No associations of individual ARV drugs with LLE were observed among two-year-olds. CONCLUSIONS In utero cARV exposure showed little association with LLE, except for a higher risk of language delay observed in one-year-old infants with atazanavir exposure
Language Impairment in Children Perinatally Infected with HIV Compared to Children Who Were HIV-Exposed and Uninfected
OBJECTIVE: To investigate risk for language impairment in children perinatally infected or exposed to HIV. METHOD: We evaluated the prevalence of language impairment (LI) in 7–16 year old children with perinatal HIV infection (HIV+) compared to children HIV-exposed and uninfected (HEU), using a comprehensive standardized language test (CELF-4). LI was classified as primary LI (Pri-LI) (monolingual English exposure and no cognitive or hearing impairment), concurrent LI (Con-LI) (cognitive or hearing impairment), or no LI. Associations of demographic, caregiver, HIV disease and antiretroviral treatment (ART) factors with LI category were evaluated using univariate and multivariable logistic regression models. RESULTS: Of 468 children with language assessments, 184 (39%) had LI. No difference was observed by HIV infection status for overall LI or for Pri-LI or Con-LI; mean (SD) CELF-4 scores were 88.5 (18.4) for HIV+ vs 87.5 (17.9) for HEU. After adjustment, Black children had higher odds of Pri-LI vs no LI (aOR=2.43, p=0.03). Children who were Black, Hispanic, had a caregiver with low education or low IQ, or a non-biological parent as caregiver had higher odds of Con-LI vs no LI. Among HIV+ children, viral load >400 copies/ml (aOR=3.04, p<0.001), CDC Class C (aOR=2.19, p=0.02) and ART initiation <6 months of age (aOR=2.12, p=0.02) were associated with higher odds of Con-LI vs. no LI. CONCLUSIONS: Children perinatally exposed to HIV are at high risk for LI, but such risk was not increased for youth with HIV. Risk factors differed for Pri-LI and Con-LI
Language Impairment in Children Perinatally Infected with HIV Compared to Children Who Were HIV-Exposed and Uninfected
Objective - To investigate risk for language impairment in children perinatally infected or exposed to HIV.
Methods - We evaluated the prevalence of language impairment (LI) in 7–16 year old children with perinatal HIV infection (HIV+) compared to children HIV-exposed and uninfected (HEU), using a comprehensive standardized language test (CELF-4). LI was classified as primary LI (Pri-LI) (monolingual English exposure and no cognitive or hearing impairment), concurrent LI (Con-LI) (cognitive or hearing impairment), or no LI. Associations of demographic, caregiver, HIV disease and antiretroviral treatment (ART) factors with LI category were evaluated using univariate and multivariable logistic regression models.
Results - Of 468 children with language assessments, 184 (39%) had LI. No difference was observed by HIV infection status for overall LI or for Pri-LI or Con-LI; mean (SD) CELF-4 scores were 88.5 (18.4) for HIV+ vs 87.5 (17.9) for HEU. After adjustment, Black children had higher odds of Pri-LI vs no LI (aOR=2.43, p=0.03). Children who were Black, Hispanic, had a caregiver with low education or low IQ, or a non-biological parent as caregiver had higher odds of Con-LI vs no LI. Among HIV+ children, viral load \u3e400 copies/ml (aOR=3.04, pp=0.02) and ART initiation (aOR=2.12, p=0.02) were associated with higher odds of Con-LI vs. no LI.
Conclusions - Children perinatally exposed to HIV are at high risk for LI, but such risk was not increased for youth with HIV. Risk factors differed for Pri-LI and Con-LI
Recommended from our members
Decline in CD4 T lymphocytes with monotherapy bridging strategy for non-adherent adolescents living with HIV infection: Results of the IMPAACT P1094 randomized trial
Introduction
Management of persistently non-adherent youth living with HIV (YLHIV) with virologic failure (VF) on combination antiretroviral therapy (cART) remains challenging. One strategy has been using 3TC/ FTC monotherapy (3TC/FTC), which in the presence of the M184V resistance mutation, does not suppress viral replication nor select for additional drug resistance mutations, and reduces viral fitness with limited side effects. P1094 compared the immunologic outcome of continuing failing cART vs. switching to 3TC/FTC as a “bridging strategy” to subsequent suppressive cART for non-adherent YLHIV with pre-existing M184V resistance.
Materials & methods
Participants with documented nonadherence, M184V mutation, CD4+ T cell count ≥100 cells/mm3 and VF (HIV-1 plasma RNA ≥400 copies/mL (2.6 log10 HIV-1 RNA) were enrolled and randomized to continue failing cART vs. switch to 3TC/FTC. The primary endpoint (time to ≥30% CD4+ T cell decline or development of CDC class C events) at 28-weeks were assessed by Kaplan-Meier (K-M) curves in an intent-to-treat analysis.
Results
Thirty-three perinatally acquired YLHIV participants (16 continuing cART and 17 3TC/FTC) enrolled in the study. The median age, entry CD4+ T cell count, and viral load were 15 years (Inter-quartile range (IQR) 14–20), 472 cells/mm3 (IQR 384–651), and 4.0 log10HIV-1 RNA copies/ml (IQR 3.2–4.5), respectively. Five participants, all in the 3TC/FTC arm, reached the primary endpoint for absolute CD4+ T cell decline (p = 0.02, exact log-rank test comparing monotherapy to cART). The Kaplan-Meier estimate of probability of primary endpoint on 3TC/FTC at 28 weeks was 0.41 (standard error 0.14). There were no CDC class C events or deaths and no statistically significant difference in frequencies of adverse events between the arms.
Conclusions
Non-adherent participants randomized to 3TC/FTC were more likely than those maintained on failing cART to experience a confirmed decline in CD4+ count of ≥30%. Although this study suffers from limitations of small sample size and premature discontinuation, the randomized comparison to continuing failing cART indicates that 3TC/FTC provides inferior protection from immunologic deterioration for non-adherent youth with M184V resistance. Better alternatives to 3TC/FTC such as ART with higher barriers to resistance and novel adherence and treatment strategies for nonadherent youth are urgently needed
Aggregate risk of cardiovascular disease among adolescents perinatally infected with the human immunodeficiency virus
BACKGROUND: Perinatally HIV-infected adolescents may be susceptible to aggregate atherosclerotic cardiovascular disease risk, as measured by the Pathobiological Determinants of Atherosclerosis in Youth (PDAY) coronary arteries and abdominal aorta risk scores, as a result of prolonged exposure to HIV and antiretroviral therapy.
METHODS AND RESULTS: Coronary arteries and abdominal aorta PDAY scores were calculated for 165 perinatally HIV-infected adolescents, using a weighted combination of modifiable risk factors: dyslipidemia, cigarette smoking, hypertension, obesity, and hyperglycemia. Demographic and HIV-specific predictors of scores ≥1 were identified, and trends in scores over time were assessed. Forty-eight percent and 24% of the perinatally HIV-infected adolescents had coronary arteries and abdominal aorta scores ≥1, representing increased cardiovascular disease risk factor burden. Significant predictors of coronary arteries scores ≥1 included male sex, history of an AIDS-defining condition, longer duration of use of a ritonavir-boosted protease inhibitor, and no prior use of tenofovir. Significant predictors of abdominal aorta scores ≥1 included suppressed viral load, history of an AIDS-defining condition, and longer duration of boosted protease inhibitor use. No significant changes in coronary arteries and abdominal aorta risk scores were observed over the 4-year study period.
CONCLUSIONS: A substantial proportion of perinatally HIV-infected youth have high PDAY scores, reflecting increased aggregate atherosclerotic cardiovascular disease risk factor burden. High scores were predicted by HIV disease severity and boosted protease inhibitor use. PDAY scores may be useful in identifying high-risk youth who may benefit from early lifestyle or clinical interventions
CD4+ and viral load outcomes of antiretroviral therapy switch strategies after virologic failure of combination antiretroviral therapy in perinatally HIV-infected youth in the United States
Objective: This study compared 12-month CD4+ and viral load outcomes in HIV-infected children and adolescents with virological failure, managed with four treatment switch strategies. Design: This observational study included perinatally HIV-infected (PHIV) children in the Pediatric HIV/AIDS Cohort Study (PHACS) and Pediatric AIDS Clinical Trials (PACTG) Protocol 219C. Methods: Treatment strategies among children with virologic failure were compared: continue failing combination antiretroviral therapy (cART); switch to new cART; switch to drug-sparing regimen; and discontinue all ART. Mean changes in CD4+% and viral load from baseline (time of virologic failure) to 12 months follow-up in each group were evaluated using weighted linear regression models. Results: Virologic failure occurred in 939 out of 2373 (40%) children. At 12 months, children switching to new cART (16%) had a nonsignificant increase in CD4+% from baseline, 0.59 percentage points [95% confidence interval (95% CI) −1.01 to 2.19], not different than those who continued failing cART (71%) (−0.64 percentage points, P = 0.15) or switched to a drug-sparing regimen (5%) (1.40 percentage points, P = 0.64). Children discontinuing all ART (7%) experienced significant CD4+% decline −3.18 percentage points (95% CI −5.25 to −1.11) compared with those initiating new cART (P = 0.04). All treatment strategies except discontinuing ART yielded significant mean decreases in log10VL by 12 months, the new cART group having the largest drop (−1.15 log10VL). Conclusion: In PHIV children with virologic failure, switching to new cART was associated with the best virological response, while stopping all ART resulted in the worst immunologic and virologic outcomes and should be avoided. Drug-sparing regimens and continuing failing regimens may be considered with careful monitoring
Maternal and infant renal safety following tenofovir disoproxil fumarate exposure during pregnancy in a randomized control trial
Background
Tenofovir disoproxil fumarate (TDF) in combination with other antiretroviral (ARV) drugs has been in clinical use for HIV treatment since its approval in 2001. Although the effectiveness of TDF in preventing perinatal HIV infection is well established, information about renal safety during pregnancy is still limited.
Trial design
The IMPAACT PROMISE study was an open-label, strategy trial that randomized pregnant women to one of three arms: TDF based antiretroviral therapy (ART), zidovudine (ZDV) based ART, and ZDV alone (standard of care at start of enrollment). The P1084s substudy was a nested, comparative study of renal outcomes in women and their infants.
Methods
PROMISE participants (n = 3543) were assessed for renal dysfunction using calculated creatinine clearance (CrCl) at study entry (> 14 weeks gestation), delivery, and postpartum weeks 6, 26, and 74. Of these women, 479 were enrolled in the P1084s substudy that also assessed maternal calcium and phosphate as well as infant calculated CrCl, calcium, and phosphate at birth.
Results
Among the 1338 women who could be randomized to TDF, less than 1% had a baseline calculated CrCl below 80 mL/min. The mean (standard deviation) maternal calculated CrCl at delivery in the TDF-ART arm [147.0 mL/min (51.4)] was lower than the ZDV-ART [155.0 mL/min (43.3); primary comparison] and the ZDV Alone [158.5 mL/min (45.0)] arms; the mean differences (95% confidence interval) were − 8.0 mL/min (− 14.5, − 1.5) and − 11.5 mL/min (− 18.0, − 4.9), respectively. The TDF-ART arm had lower mean maternal phosphate at delivery compared with the ZDV-ART [− 0.14 mg/dL (− 0.28, − 0.01)] and the ZDV Alone [− 0.17 mg/dL (− 0.31, − 0.02)] arms, and a greater percentage of maternal hypophosphatemia at delivery (4.23%) compared with the ZDV-ART (1.38%) and the ZDV Alone (1.46%) arms. Maternal calcium was similar between arms. In infants, mean calculated CrCl, calcium, and phosphate at birth were similar between arms (all CIs included 0).
Conclusions
Although mean maternal calculated CrCl at Delivery was lower in the TDF-ART arm, the difference between arms is unlikely to be clinically significant. During pregnancy, the TDF-ART regimen had no observed safety concerns for maternal or infant renal function.
Trial Registration: NCT01061151 on 10/02/2010 for PROMISE (1077BF). NCT01066858 on 10/02/2010 for P1084s
- …