Marilyn J. Crain

In utero nucleoside reverse transcriptase inhibitor exposure and signs of possible mitochondrial dysfunction in HIV-uninfected children.

Background:There is equivocal evidence of in utero nucleoside reverse transcriptase inhibitor (NRTI) exposure and the occurrence of mitochondrial dysfunction (MD) in HIV-uninfected children born of HIV-infected women. Methods:The primary analysis included 1037 HIV-uninfected children born in 1991–2002 and enrolled in Pediatric AIDS Clinical Trials Group protocols 219/219C. Possible cases with unexplained signs of MD according to the Enquête Périnatale Française criteria were identified through retrospective review. Associations between overall in utero NRTI exposure, and trimester of first in utero NRTI exposure and possible MD were estimated with exact logistic regression. Results:Cases (n = 20) were significantly more likely to be male and to be born in earlier years than non-cases (n = 1017). There was no association between overall in utero NRTI exposure and MD. In unadjusted models there were higher odds of first in utero exposure in the third trimester to lamivudine (3TC) [odds ratio (OR), 3.76 versus 3TC unexposed; 95% confidence interval (CI), 1.09–11.78] and to zidovudine (ZDV) and 3TC in combination (ZDV/3TC) (OR, 3.29 vs. ZDV/3TC unexposed; 95% CI, 0.96–10.25) among cases than noncases. When adjusted for year of birth the odds of first exposure in the third trimester to 3TC (OR, 10.57; 95% CI, 1.93–75.61) and ZDV/3TC (OR, 9.84; 95% CI, 1.77–71.68) were significantly higher among cases than non-cases. Incomplete data precluded control of possible confounding by maternal viral load and psychoactive drug use. Conclusions:Our study suggests that first exposure to 3TC or ZDV/3TC in the third trimester may be associated with the occurrence of possible MD. Further studies that rigorously assess MD and better control confounding are needed.

Prevalence of elevated cholesterol and associated risk factors among perinatally HIV-infected children (4-19 years old) in Pediatric AIDS Clinical Trials Group 219C.

Background:HIV protease inhibitors (PIs) are known to disturb lipid metabolism in adults, leading to hypercholesterolemia. A number of cross-sectional studies have also reported this phenomenon in perinatally HIV-infected children but differ greatly with respect to prevalence and/or methodology. Methods:The Pediatric AIDS Clinical Trials Group 219C (PACTG 219C) is a prospective cohort study designed to examine long-term outcomes in children born to HIV-infected women. The outcome of interest in this analysis was total cholesterol, and patients were classified as hypercholesterolemic if their total cholesterol was above the 95th percentile of US Third National Health and Nutrition Survey (NHANES III) standards for gender, race/ethnicity, and age. We hypothesized that hypercholesterolemia would be more common among older children receiving PI therapy who demonstrated excellent adherence and might be associated with hypertension and obesity. Information regarding treatment, adherence, and laboratory values was obtained using the date closest to the cholesterol measurement. Crude and adjusted effect measures were estimated using exposure odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) from univariate and multivariate logistic regression models. Results:Among 1812 HIV-infected participants between 4 and 19 years of age, 229 children had hypercholesterolemia (prevalence = 13.0%, 95% CI: 11.1-14.3) compared with 9 of 187 HIV-uninfected children (prevalence = 4.8%, 95% CI: 2.2-8.8). After adjusting for confounders, current PI use (OR = 5.3, 95% CI: 3.1-9.2), age from 4 to <6 years (OR = 2.9, 95% CI: 1.7-4.9), HIV-1 RNA <400 copies/mL (OR = 2.3, 95% CI: 1.7-3.2), self-report of no missed doses in the past 3 days (OR = 2.2, 95% CI: 1.3-3.8), white race (OR = 2.2, 95% CI: 1.4-3.3), age from 6 to <12 years (OR = 1.9, 95% CI: 1.3-2.9), Hispanic ethnicity (OR = 1.8, 95% CI: 1.2-2.5), and current nonnucleoside reverse transcriptase inhibitor use (OR = 1.7, 95% CI: 1.2-2.3) were independently associated with the presence of hypercholesterolemia among the HIV-infected children. There was a positive association with elevated systolic blood pressure in univariate but not multivariate analysis, and no association was present with body mass index. Conclusions:Among the HIV-infected children, the overall prevalence of hypercholesterolemia was 13.0% and the strongest associated risk factor for hypercholesterolemia was current use of a PI in the antiretroviral regimen. Continued follow-up is needed to assess the long-term effects of hypercholesterolemia in children.

Human antibodies to pneumococcal surface protein A in health and disease.

Background. Diseases caused by Streptococcus pneumoniae have a high impact in young children whose ability to mount antibodies to capsular polysaccharides is impaired. Pneumococcal surface protein A (PspA) is a potential vaccine candidate for this age group. Methods. We used Western blot analysis and enzyme immunoassay to study human sera of healthy adults from Alabama (n = 20) and from Finland (n = 21), healthy children from Finland (n = 20) and ill children from Finland, those with pneumococcal invasive infection (n = 26) and those with nonpneumococcal invasive infection (n = 26). Results. Human antibodies to PspA exhibited strong cross‐reactivity among different pneumococcal strains. The geometric mean titer of IgG antibody to PspA in sera from 21 healthy adults was 4040, from ten 3‐year‐old healthy children 1080 and from ten 2‐month‐old healthy children 1650. The geometric mean titer of PspA antibody of acute phase sera of children with invasive pneumococcal disease was 140, significantly (P < 0.001) lower than the respective value, 1020, for children with infection caused by other bacteria. Conclusions. We demonstrate for the first time the existence of antibodies to PspA in human sera in health and disease. The findings in ill children suggest that antibodies to PspA might play a role in protection against pneumococcal disease.

Association of Hypercholesterolemia Incidence With Antiretroviral Treatment, Including Protease Inhibitors, Among Perinatally HIV-Infected Children

Context:Antiretroviral therapy has been associated with hypercholesterolemia in HIV-infected children. Few longitudinal studies have been conducted to examine this association, however. Objective:To evaluate the incidence of and risk factors for development of hypercholesterolemia in a large pediatric study. Design:Prospective cohort study (Pediatric AIDS Clinical Trials Group 219C). Participants:A total of 2122 perinatally HIV-infected children free of hypercholesterolemia at entry. Outcome:Development of hypercholesterolemia (total cholesterol ≥220 mg/dL at 2 consecutive visits). Cox proportional hazards models were used to evaluate risk factors. Results:Thirteen percent of children had hypercholesterolemia at entry, and an additional 13% developed hypercholesterolemia during follow-up for an incidence rate of 3.4 cases per 100 person-years (95% confidence interval [CI]: 3.0 to 3.9). After adjustment for age, boosted protease inhibitor (PI) use (hazard ratio [HR] = 13.9, 95% CI: 6.73 to 28.6), nonboosted PI use (HR = 8.65, 95% CI: 4.19 to 17.9), and nonnucleoside reverse transcriptase inhibitor use (HR = 1.33, 95% CI: 1.04 to 1.71) were associated with increased risk of hypercholesterolemia, and higher viral load was protective (>50,000 vs. ≤400 copies/mL; HR = 0.59, 95% CI: 0.39 to 0.90). Self-reported adherent subjects had higher risk. Conclusions:PIs were significant risk factors for hypercholesterolemia. Higher viral load was protective and may reflect nonadherence. Further follow-up is critical to evaluate long-term consequences of chronic PI exposure and hypercholesterolemia.

The IS1167 insertion sequence is a phylogenetically informative marker among isolates of serotype 6B Streptococcus pneumoniae.

Abstract. The phylogenetic utility of the IS1167 insertion sequence was examined with restriction fragment length polymorphism (RFLP) analyses of a sample of 50, predominantly invasive, capsular serotype 6B Streptococcus pneumoniae isolates previously characterized by multilocus enzyme electrophoresis (MLEE). The strains represented a genetically diverse assemblage of 34 distinct clonotypes composed of 26 restriction fragment types and 23 multilocus enzyme types. All isolates carried the IS1167 insertion sequence, with an average of 9.5 copies. The cross-classification of isolates based on RFLP and MLEE typing schemes was 81% concordant. Phylogenetic analyses demonstrated a significant (P < 0.0001) association between strains of a given RFLP lineage with those of a given MLEE lineage. A significant correlation (P < 0.00004) was also found between the proportion of restriction fragments shared by any given pair of isolates and their genetic distances estimated from the MLEE data. Parity between the two genetic markers implied that the sampled isolates were in linkage disequilibrium. The existence of nonrandom associations among genetic loci was confirmed by Monte Carlo analyses of the MLEE data. These studies, thus, demonstrated that invasive pneumococcal isolates of a single capsule type recovered on a regional scale can retain a largely clonal population structure over a period of 8 years. The ability to detect linkage disequilibrium and generate relatively congruent dendrograms based on distance and parsimony methods suggested that the restriction fragment data were robust to phylogenetic analysis.

Risk factors for nasopharyngeal carriage of resistant Streptococcus pneumoniae and detection of a multiply resistant clone among children living in the Yukon-Kuskokwim delta Region of Alaska

BACKGROUND Children < 2 years old living in the Yukon-Kuskokwim Delta (YKD) region of Alaska have one of the highest pneumococcal bacteremia rates of in the world. METHODS To determine the prevalence of and risk factors for infection with intermediate or resistant Streptococcus pneumoniae in the YKD, we cultured nasopharyngeal secretions of healthy children < or = 5 years old, reviewed their hospital records and administered questionnaires to accompanying parents. RESULTS Of 185 children evaluated we obtained 95 pneumococcal isolates; drug susceptibility patterns and serotyping results were available for 92. Of these, 33 (36%) were intermediate or resistant to at least one drug class tested; 27 isolates were intermediate (minimum inhibitory concentration 0.1 to 1.0 mg/l) and none were resistant to penicillin. Compared with other isolates, capsular serotype 6B isolates were more likely to be intermediate or resistant to at least one drug (relative risk, 5.3; P < 0.001) and to more than one drug (relative risk, 17.0; P < 0.001). The majority of 6B isolates had identical pneumococcal surface protein A patterns. Carriage of intermediate or resistant pneumococcus was associated with age < 2 years (relative risk, 3.0; P < 0.001) but not with antibiotic use or other evaluated risk factors. CONCLUSIONS Young age but not antibiotic use was associated with carriage of intermediate or resistant S. pneumoniae in the YKD region of Alaska. Much of the intermediate or resistant pneumococcus in the YKD may have resulted from the proliferation of a single capsular serotype 6B clone.

Clones of Streptococcus pneumoniae Isolated from Nasopharyngeal Carriage and Invasive Disease in Young Children in Central Tennessee

To determine whether nasopharyngeal carriage isolates of Streptococcus pneumoniae are of the same genetic background as isolates that caused invasive disease in one community, IS1167 and boxA genotypes were obtained for 182 pneumococcal isolates from children living in central Tennessee. The isolates represented 70 combined IS1167-boxA genotypes. The genotypic diversity of the invasive isolates was significantly less than that of the total population (P=.003). Most of the carriage isolates belonged to genotypes unique to carriage, whereas most of the invasive isolates belonged to genotypes common to carriage and disease (P=.02). Monte Carlo simulations showed a greater number of genotypes unique to carriage than can be explained by chance (P<.05 in all cases). Two genotypes were identified by multilocus sequence typing as members of globally disseminated clones, and one such genotype that was strictly carriage in this sample caused disease in other studies. Thus, clones can have different propensities for carriage and invasion.

In Utero and Postnatal Exposure to Antiretrovirals Among HIV-Exposed But Uninfected Children in the United States

An increasing number of antiretroviral agents (ARVs) are approved for use, but their use during pregnancy in the United States has not been completely described. We used data from the Pediatric HIV/AIDS Cohort Study (PHACS) Surveillance Monitoring for ART Toxicities (SMARTT) study, a United States-based prospective cohort study of HIV-exposed but uninfected children, to assess temporal trends and maternal characteristics associated with the use of ARVs during pregnancy. The proportion of children exposed in utero to ARVs was calculated over time. A multivariable logistic regression model was used to estimate associations of maternal characteristics with use of highly active antiretroviral therapy (HAART) during pregnancy. We studied 1768 HIV-exposed but uninfected children born between 1995 and 2009 and enrolled in SMARTT. Prenatal HAART exposure increased from 19% in 1997 to 88% in 2009. Of children born in 2009, 99% had prenatal exposure to NRTIs (including zidovudine, 73%; lamivudine, 72%; tenofovir, 39%; and emtricitabine, 37%). Exposure to protease inhibitors increased from 15% in 1997 to 86% in 2009, while exposure to non-nucleoside reverse transcriptase inhibitors (NNRTIs) declined from 33% in 2003 to 11% in 2009. Higher maternal HIV RNA viral load (VL) concentration, lower maternal CD4 count, and earlier timing of the first maternal CD4 or VL measurement during pregnancy were associated with increased odds of HAART exposure. Prenatal HAART exposure has increased but is not universal. As ARV use during pregnancy continues to evolve, follow-up of children is needed to assess long-term effects of ARV exposures.

Congenital Anomalies and In Utero Antiretroviral Exposure in Human Immunodeficiency Virus-Exposed Uninfected Infants

IMPORTANCE Most studies examining the association of prenatal antiretroviral (ARV) exposures with congenital anomalies (CAs) in children born to human immunodeficiency virus (HIV)-infected women have been reassuring, but some evidence suggests an increased risk with specific ARV agents. OBJECTIVE To evaluate the association of in utero ARV exposures with CAs in HIV-exposed uninfected children. DESIGN, SETTING, AND PARTICIPANTS Prospective cohort study design. The Pediatric HIV/AIDS Cohort Studys Surveillance Monitoring of ART Toxicities (SMARTT) Study was performed at 22 US medical centers among 2580 HIV-exposed uninfected children enrolled in the SMARTT Study between March 23, 2007, and June 18, 2012. EXPOSURES First-trimester exposure to any ARV and to specific ARV medications. MAIN OUTCOMES AND MEASURES The primary end point was a CA based on physician review of infant physical examinations according to the Antiretroviral Pregnancy Registry modification of the Metropolitan Atlanta Congenital Defects Program. Rates of CAs were estimated overall and by birth year. Logistic regression models were used to evaluate the association of CAs with first-trimester ARV exposures, adjusting for demographic and maternal characteristics. RESULTS Congenital anomalies occurred in 175 of 2580 children, yielding a prevalence of 6.78% (95% CI, 5.85%-7.82%); 242 major CAs were confirmed, including 72 musculoskeletal and 55 cardiovascular CAs. The prevalence of CAs increased significantly among successive birth cohorts (3.8% for children born before 2002 and up to 8.3% for those born 2008-2010). In adjusted models, no association of first-trimester exposures with CAs was found for any ARV, for combination ARV regimens, or for any drug class. No individual ARV in the reverse transcriptase inhibitor drug classes was associated with an increased risk of CAs. Among protease inhibitors, higher odds of CAs were observed for atazanavir sulfate (adjusted odds ratio [aOR], 1.95; 95% CI, 1.24-3.05) and for ritonavir used as a booster (aOR, 1.56; 95% CI, 1.11-2.20). With first-trimester atazanavir exposure, risks were highest for skin (aOR, 5.23) and musculoskeletal (aOR, 2.55) CAs. CONCLUSIONS AND RELEVANCE Few individual ARVs and no drug classes were associated with an increased risk of CAs in HIV-exposed infants after adjustment for calendar year and maternal characteristics. While the overall risk remained low, a relative increase was observed in successive years and with atazanavir exposure. Given the low absolute CA risk, the benefits of recommended ARV therapy use during pregnancy still outweigh such risks, although further studies are warranted.

Possible Mitochondrial Dysfunction and Its Association with Antiretroviral Therapy Use in Children Perinatally Infected with HIV

BACKGROUND Mitochondrial dysfunction has been associated with both human immunodeficiency virus (HIV) infection and exposure to antiretroviral therapy. Mitochondrial dysfunction has not been widely studied in HIV-infected children. We estimated the incidence of clinically defined mitochondrial dysfunction among children with perinatal HIV infection. METHODS Children with perinatal HIV infection enrolled in a prospective cohort study (Pediatric AIDS Clinical Trials Group protocols 219 and 219C) from 1993 through 2004 were included. Two clinical case definitions of mitochondrial dysfunction, the Enquête Périnatale Française criteria and the Mitochondrial Disease Classification criteria, were used to classify signs and symptoms that were consistent with possible mitochondrial dysfunction. Adjusted odds ratios of the associations between single and dual nucleoside reverse-transcriptase inhibitor use and possible mitochondrial dysfunction were estimated using logistic regression. RESULTS Overall, 982 (33.5%) of 2931 children met 1 or both case definitions of possible mitochondrial dysfunction. Mortality was highest among the 96 children who met both case definitions (20%). After adjusting for confounders, there was a higher risk of possible mitochondrial dysfunction among children who received stavudine regardless of exposure to other medications (odds ratio, 3.44 [95% confidence interval, 1.91-6.20]) or who received stavudine-didanosine combination therapy (odds ratio, 2.23 [95% confidence interval, 1.19-4.21]). Exposure to lamivudine and to lamivudine-stavudine were also associated with an increased risk of mitochondrial dysfunction. CONCLUSIONS Receipt of nucleoside reverse-transcriptase inhibitors, especially stavudine and lamivudine, was associated with possible mitochondrial dysfunction in children with perinatal HIV infection. Further studies are warranted to elucidate potential mechanisms of nucleoside reverse-transcriptase inhibitor toxicities.