Brief Report: Diagnostic Accuracy of Oral Mucosal Transudate Tests Compared with Blood-Based Rapid Tests for HIV Among Children Aged 18 Months to 18 Years in Kenya and Zimbabwe.

BACKGROUND: Gaps persist in HIV testing for children who were not tested in prevention of mother-to-child HIV transmission programs. Oral mucosal transudate (OMT) rapid HIV tests have been shown to be highly sensitive in adults, but their performance has not been established in children. METHODS: Antiretroviral therapy-naive children aged 18 months to 18 years in Kenya and Zimbabwe were tested for HIV using rapid OraQuick ADVANCE Rapid HIV-1/2 Antibody test on oral fluids (OMT) and blood-based rapid diagnostic testing (BBT). BBT followed Kenyan and Zimbabwean national algorithms. Sensitivity and specificity were calculated using the national algorithms as the reference standard. RESULTS: A total of 1776 children were enrolled; median age was 7.3 years (interquartile range: 4.7-11.6). Among 71 children positive by BBT, all 71 were positive by OMT (sensitivity: 100% [97.5% confidence interval (CI): 94.9% to 100%]). Among the 1705 children negative by BBT, 1703 were negative by OMT (specificity: 99.9% [95% CI: 99.6% to 100.0%]). Due to discrepant BBT and OMT results, 2 children who initially tested BBT-negative and OMT-positive were subsequently confirmed positive within 1 week by further tests. Excluding these 2 children, the sensitivity and specificity of OMT compared with those of BBT were each 100% (97.5% CI: 94.9% to 100% and 99.8% to 100%, respectively). CONCLUSIONS: Compared to national algorithms, OMT did not miss any HIV-positive children. These data suggest that OMTs are valid in this age range. Future research should explore the acceptability and uptake of OMT by caregivers and health workers to increase pediatric HIV testing coverage

Incidence and Correlates of HIV-1 RNA Detection in the Breast Milk of Women Receiving HAART for the Prevention of HIV-1 Transmission

The incidence and correlates of breast milk HIV-1 RNA detection were determined in intensively sampled women receiving highly active antiretroviral therapy (HAART) for the prevention of mother-to-child HIV-1 transmission.Women initiated HAART at 34 weeks of pregnancy. Breast milk was collected every 2-5 days during 1 month postpartum for measurements of cell-associated HIV DNA and cell-free HIV RNA. Plasma and breast milk were also collected at 2 weeks, 1, 3 and 6 months for concurrent HIV-1 RNA and DNA measurements. Regression was used to identify cofactors for breast milk HIV-1 RNA detection.Of 259 breast milk specimens from 25 women receiving HAART, 34 had detectable HIV-1 RNA (13%, incidence 1.4 episodes/100 person-days 95% CI = 0.97-1.9). Fourteen of 25 (56%) women had detectable breast milk HIV-1 RNA [mean 2.5 log(10) copies/ml (range 2.0-3.9)] at least once. HIV-1 DNA was consistently detected in breast milk cells despite HAART, and increased slowly over time, at a rate of approximately 1 copy/10(6) cells per day (p = 0.02). Baseline CD4, plasma viral load, HAART duration, and frequency of breast problems were similar in women with and without detectable breast milk HIV-1 RNA. Women with detectable breast milk HIV-1 RNA were more likely to be primiparous than women without (36% vs 0%, p = 0.05). Plasma HIV-1 RNA detection (OR = 9.0, 95%CI = 1.8-44) and plasma HIV-1 RNA levels (OR = 12, 95% CI = 2.5-56) were strongly associated with concurrent detection of breast milk HIV-1 RNA. However, no association was found between breast milk HIV-1 DNA level and concurrent breast milk HIV-1 RNA detection (OR = 0.96, 95%CI = 0.54-1.7).The majority of women on HAART had episodic detection of breast milk HIV-1 RNA. Breast milk HIV-1 RNA detection was associated with systemic viral burden rather than breast milk HIV-1 DNA

The Potential Harm of Cytomegalovirus Infection in Immunocompetent Critically Ill Children

Cytomegalovirus (CMV) is a ubiquitous infection that causes disease in congenitally infected children and immunocompromised patients. Although nearly all CMV infections remain latent and asymptomatic in immunologically normal individuals, numerous studies have found that systemic viral reactivation is common in immunocompetent critically ill adults, as measured by detection of CMV in the blood (viremia). Furthermore, CMV viremia is strongly correlated with adverse outcomes in the adult intensive care unit (ICU), including prolonged stay, duration of mechanical ventilation, and death. Increasing evidence, including from a randomized clinical trial of antiviral treatment, suggests that these effects of CMV may be causal. Therefore, interventions targeting CMV might improve outcomes in adult ICU patients. CMV may have an even greater impact on critically ill children, particularly in low and middle income countries (LMIC), where CMV is regularly acquired in early childhood, and where inpatient morbidity and mortality are inordinately high. However, to date, there are few data regarding the clinical relevance of CMV infection or viremia in immunocompetent critically ill children. We propose that CMV infection should be studied as a potential modifiable cause of disease in critically ill children, and that these studies be conducted in LMIC. Below, we briefly review the role of CMV in immunologically normal critically ill adults and children, outline age-dependent differences in CMV infection that may influence ICU outcomes, and describe an agenda for future research

The impact of HIV-1 infection and exposure on natural killer (NK) cell phenotype in Kenyan infants during the first year of life

Natural killer (NK) cells play an important role in the containment of HIV replication during primary infection, though their functions are impaired during chronic HIV infection. Infants experience more rapid HIV disease progression than adults, but contributions of infant NK cells to containing HIV infection are unknown. The aim of this study was to determine the impact of HIV infection on infant NK cell phenotype by evaluating samples and data from a cohort study of women and their infants, conducted in Nairobi, Kenya between 1999-2003. The percentage and phenotype of NK cells was evaluated longitudinally by multi-parameter flow cytometry over the first year of life in HIV-infected (HIV+, n=16), HIV-exposed uninfected (HIV-EU, n=6), and healthy unexposed controls (HIV-, n=4). At birth, NK subset distributions based on expression of CD56 and CD16 did not differ between HIV+, HIV-EU, or HIV- infants. However, HIV infection was associated with a subsequent decline in NK cells as a percentage of total lymphocytes (p<0.001), and an expanding proportion of CD56-CD16+ NK cells (p<0.001). Activated CD38brightCD69+ NK cells were more frequent in the HIV+ infants, followed by HIV-EU and HIV- infants, in both CD56dim (p=0.005) and CD56bright compartments (p=0.03). HIV infection and exposure was also associated with a significant decline in the percentage of perforin-expressing NK cells in the CD56dim compartment over the first year of life, with HIV+ infants losing approximately 2.5% (p<0.001) and HIV-EU infants losing 3.0% (p=0.01) of perforin+ cells per month. Thus, infant HIV infection is associated with alterations in NK cell subsets, activation, and cytolytic potential that could contribute to their poor control over HIV infection. Furthermore, exposure to HIV infection in infants who escaped infection is also associated with alterations in NK cells that may contribute to the reduced ability to fight infections that is observed in HIV-EU infants

Maternal Highly Active Antiretroviral Therapy Reduces Vertical Cytomegalovirus Transmission But Does Not Reduce Breast Milk Cytomegalovirus Levels

To evaluate the impact of highly active antiretroviral therapy (HAART) on CMV transmission and breast milk level in the context of maternal HIV. Specimens from a randomized trial conducted in Nairobi, Kenya between 2003–2005 were used to compare CMV transmission and breast milk levels between mother-infant pairs randomized to HAART versus short-course antenatal zidovudine plus single-dose nevirapine (ZDV/sdNVP) for prevention of mother-to-child HIV transmission (PMTCT). Fifty-one antiretroviral-naïve women ≤32 weeks gestation, and CD4 between 200–500 cells/mm3 were randomized at 34 weeks to begin either antenatal ZDV/sdNVP, or HAART through 6 months postpartum. Mean breast milk CMV levels and transmission were compared between arms. Age, sociodemographics, CD4%, and HIV plasma RNA viral load were similar between arms at baseline. CMV viral loads were measured from 243 infant plasma and 185 breast milk specimens during the first year postpartum. The probability of infant CMV infection at 12 months was 19% lower in the HAART arm compared to ZDV/sdNVP (75% vs. 94%, p = .04). All women had CMV detected in breast milk, with 72%, 98%, and 97% testing positive during the first, second, and third weeks postpartum, respectively. There was a trend for early higher mean breast milk CMV level in the HAART arm at 1 week (p = .08), and there was significantly slower decline in breast milk CMV levels (area under the curve, p = .01). HAART started during the third trimester may decrease infant CMV infections, by mechanisms independent of breast milk CMV levels. Clinical trials registration: NCT00167674

Salivary Cathelicidin (LL-37) in Children and Adolescents Living with HIV

Introduction: Human cathelicidin LL-37 is a salivary antimicrobial peptide (AMP) with broad-spectrum activity against oral diseases, but few studies have assessed its role in children and adolescents living with HIV (CALHIV). We assessed salivary LL-37 levels and correlates in a long-term cohort of Kenyan CALHIV followed since antiretroviral therapy (ART) initiation. Methods: Saliva was collected from 76 CALHIV who were recruited from two ongoing pediatric HIV studies in Nairobi, Kenya. Oral examinations documenting oral manifestations of HIV, dental caries, and gingivitis were completed. Additional variables included age, sex, HIV treatment (initial ART regimen) and disease parameters, caregivers’ demographics, and oral pathologies were conducted. Data were statistically analyzed using the independent T test on the log-transformed LL-37. Results: At the oral exam visit, the mean age of participants was 13.3 years (±SD = 3.4), and the median CD4 count was 954 cells/mm3. Mean salivary cathelicidin values of the cohort were 23.7 ± 21.1 ng/mL. Children with permanent dentition at time of oral examination, and children who initiated ART at ≥2 years old had higher mean LL-37 concentrations compared to those with mixed dentition and those who initiated ART <2 years old (p = 0.0042, 0.0373, respectively). LL-37 levels were not found to differ by initial type of ART regimen, CD4 count, or oral disease. Conclusion: Further research and longitudinal studies are necessary to evaluate and improve the innate immunity of CALHIV in Kenya

Longitudinal Assessment of Human Immunodeficiency Virus Type 1 (HIV-1)-Specific Gamma Interferon Responses during the First Year of Life in HIV-1-Infected Infants

Human immunodeficiency virus type 1 (HIV-1) infection results in different patterns of viral replication in pediatric compared to adult populations. The role of early HIV-1-specific responses in viral control has not been well defined, because most studies of HIV-1-infected infants have been retrospective or cross-sectional. We evaluated the association between HIV-1-specific gamma interferon (IFN-γ) release from the cells of infants of 1 to 3 months of age and peak viral loads and mortality in the first year of life among 61 Kenyan HIV-1-infected infants. At 1 month, responses were detected in 7/12 (58%) and 6/21 (29%) of infants infected in utero and peripartum, respectively (P = 0.09), and in ∼50% of infants thereafter. Peaks of HIV-specific spot-forming units (SFU) increased significantly with age in all infants, from 251/10(6) peripheral blood mononuclear cells (PBMC) at 1 month of age to 501/10(6) PBMC at 12 months of age (P = 0.03), although when limited to infants who survived to 1 year, the increase in peak HIV-specific SFU was no longer significant (P = 0.18). Over the first year of life, infants with IFN-γ responses at 1 month had peak plasma viral loads, rates of decline of viral load, and mortality risk similar to those of infants who lacked responses at 1 month. The strength and breadth of IFN-γ responses at 1 month were not significantly associated with viral containment or mortality. These results suggest that, in contrast to HIV-1-infected adults, in whom strong cytotoxic T lymphocyte responses in primary infection are associated with reductions in viremia, HIV-1-infected neonates generate HIV-1-specific CD8(+)-T-cell responses early in life that are not clearly associated with improved clinical outcomes