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Background: The determination of IgG levels and their subclasses can provide clinically relevant information on the status of the immune system. Here we determined the sensitivity and reproducibility of the quantification of IgG subclasses from Dried Blood Spots (DBS) in Malawian uninfected infants exposed to HIV (HEU)., Methods: Sixty paired samples of serum and DBS from HEU infants were used. Samples were collected from 1, 6, and 24-month old infants. IgGs concentrations from both serum and DBS were analyzed by BN ProSpec Siemens assay, using a different setting for sample dilutions. The reproducibility of the DBS method was tested on 10 samples run twice, starting from the DBS extraction process. To assess the systematic, proportional, and random differences, we computed the Passing-Bablok regression, and the Bland-Altman analysis to estimate the total mean bias between the two tests., Results: The IgG isotypes concentrations from serum and DBS showed significant differences in all the comparisons. Generally, the DBS method underestimated IgG subclasses' values showing a recovery range between 51.2% and 77.6%. Passing Bablok regression on age-based groups showed agreement for IgG, IgG1, and IgG2, but not for IgG3 and IgG4. The mean bias obtained with the Bland Altman test varied largely depending on IgG isotypes (-0.02-2.21 g/l) Coefficient of variation <7.0% was found in the repeated tests for IgG, IgG1, IgG3, and IgG4, while it was 12.4% for IgG2., Conclusions: Varying degrees of differences were seen in the IgGs measurement in the two different matrices. In IgGs analysis, the DBS method offers promise for population-based research, but the results should be carefully evaluated and considered as a relative value since they are not equivalent to the serum concentrations., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Objectives: Hypergammaglobulinemia and anomalies in the IgG subclass distribution are common in HIV-infected individuals and persist even after many years of antiretroviral therapy (ART). The aim of this study was to investigate the IgG profile and dynamics in pregnant HIV-infected Malawian women in the Option B era., Methods: Thirty-seven treatment-naive women received ART from the third trimester of pregnancy to 6 months post delivery (end of the breastfeeding period). ART continuation (group C) or interruption (group I) was then decided on the basis of the CD4+ cell count at enrolment (>350 or ≤350/μl). Total IgG and IgG subclasses were determined in maternal serum using a nephelometric assay at baseline and at 6 and 24 months postpartum., Results: At enrolment, 36/37 women had IgG levels >15g/l and there was a predominance of the IgG1 isotype (more than 90%) in parallel with underrepresentation of IgG2 (5.0%). After 6 months of ART, both groups showed a significant median decrease in total IgG (-3.1g/l in group I, -3.5g/l in group C) and in IgG1 (-4.0g/l and -3.6g/l, respectively), but only a modest recovery in IgG2 levels (+0.16 in group I, +0.14g/l in group C). At month 24, hypergammaglobulinemia was still present in 73.7% of women in group C, although a significant reduction was observed in total IgG level and in IgG1 and IgG3 subclasses (p<0.0001 in all cases). IgG2 levels did not show any significant change. In group I at 24 months, total IgG and IgG subclasses had returned to levels comparable to those at baseline., Conclusions: The beneficial effects of 24 months of ART appear to be limited in the B-cell compartment, with an incomplete reduction of total IgG levels and no recovery of IgG2 depletion. A short ART period did not have significant effects on IgG abnormalities in women who interrupted treatment., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objectives: The objective of this study was to determine the prevalence of drug resistance mutations among HIV-positive women in Malawi 18 months after discontinuing nevirapine-based ART for the prevention of mother-to-child transmission., Patients and Methods: HIV-infected antiretroviral-naive (except for single-dose nevirapine) pregnant Malawian women receiving a nevirapine-based triple antiretroviral regimen from Week 25 of gestation until 6 months of breastfeeding were included in this analysis. Drug resistance was assessed in HIV-DNA 24 months post-partum and at baseline (before the initiation of treatment). In patients with resistance, the presence of mutations was also evaluated in the corresponding plasma samples., Results: Seven out of 42 (16.7%) women studied had archived drug resistance at Month 24 [six cases had NNRTI-associated mutations and two cases the M184I mutation]. In four cases, resistance mutations were already present at baseline (all NNRTI mutations). In three cases, there was an emergence of 'new' resistance (also present in the plasma in one case). Of the 35 women without resistance mutations at Month 24, only one subject had resistance mutations at baseline. Baseline resistance was significantly more common among women with mutations at 24 months compared with those harbouring a WT virus (4/7 versus 1/35, P < 0.001)., Conclusions: Among women who had discontinued drugs 6 months post-partum, only 3/42 (7.1%) had accumulated new resistance mutations in HIV-DNA 2 years after delivery. These findings are reassuring in terms of the safety of the Option B strategy for the prevention of HIV mother-to-child transmission., (© The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Background: Maternal antibodies are key components of the protective responses of infants who are unable to produce their own IgG until 6 months of life. There is evidence that HIV-exposed uninfected children (HEU) have IgG levels abnormalities, that can be partially responsible for the higher vulnerability to infections in the first 2 years of the life of this population. This retrospective study aimed to characterize the dynamics in plasma levels of total IgG and their isotypes during the first 2 years of life in HEU infants exclusively breastfed through 6 months of age.Methods: Total IgG, IgG1, IgG2, IgG3 and IgG4 isotypes, and IgM and IgA plasma concentrations were determined by nephelometric methods in 30 Malawian infants born to HIV-positive women at month 1, 6 and 24 of life.Results: At 1-month infants had a median concentration of total IgG of 8.48 g/l, (IQR 7.57-9.15), with an overrepresentation of the IgG1 isotype (89.0% of total) and low levels of IgG2 (0.52 g/l, IQR, 0.46-0.65). Total IgG and IgG1 concentrations were lower at 6 months (- 2.1 and - 1.12 g/dl, respectively) reflecting disappearance of maternal antibodies, but at 24 months their levels were higher with respect to the reported reference values for age-matched pairs. Abnormal isotype distribution was still present at 24 months with IgG2 remaining strongly underrepresented (0.87 g/l, 7.5% of total IgG).Conclusion: HIV exposure during pregnancy and breastfeeding seems to influence the IgG maturation and isotype distribution that persist in 2-year old infants. [ABSTRACT FROM AUTHOR]

Abstract: Problem: Data on soluble CD14 (sCD14) during pregnancy and lactation are scarce. We assessed the levels of sCD14 in plasma and breastmilk of Malawian HIV‐positive women and evaluated the possible association with morbidity and mortality in the HIV‐exposed children. Method of study: One hundred and forty‐nine mother/child pairs were studied. Women received antiretroviral therapy from 26 weeks of gestation to at least 6 months of exclusive breastfeeding. sCD14 concentrations were determined using an enzyme‐linked immunosorbent assay. Results: sCD14 levels measured at 26 weeks of pregnancy (median: 1418 ng/mL, IQR: 1086‐1757) were inversely correlated to maternal CD4+ cell count (r = −.283, P = .001) and to neonatal birthweight (r = −.233, P = .008). At 6 months, sCD14 plasma levels were significantly higher compared to baseline (1993 ng/mL, IQR: 1482‐2604, P < .001), and breastmilk sCD14 levels (7668 ng/mL, IQR: 5495‐10207) were 4‐fold higher than in plasma (although the concentrations in the two compartments were not correlated). No association was found between sCD14 levels in plasma or breastmilk and morbidity or mortality in children. Conclusion: Higher sCD14 levels in HIV‐positive women were associated with a more compromised maternal immunological status and to a lower neonatal birthweight, but not to poorer clinical outcomes in the HIV‐exposed children. [ABSTRACT FROM AUTHOR]

Background: We describe the accumulation of HIV-1 drug resistance and its effect on the activity of next-line components in patients with virological failure (HIV-1 RNA >1000 copies/mL) after 1 year (t1) of first-line antiretroviral therapy (ART) not switching to second-line drugs for one additional year (t2) in low-middle income countries (LMIC).Methods and Results: We selected 48 patients from the DREAM cohort (Maputo, Mozambique); their median pre-ART CD4+ cell count was 165 cells/μl. At t1 patients were receiving ART since a median of 12.2 months (mainly zidovudine/lamivudine/nevirapine), their median HIV RNA was 3.8 log10 copies/mL, 43 (89.6%) presented at least one resistance-associated mutation (RAM), most frequently for lamivudine/emtricitabine, nevirapine and efavirenz. Resistance to tenofovir, was 10% at 1 year and higher than 20% at 2 years, while projection at 3 years was >30%. At t2, 42 (89.4%) had a predicted low-level or higher resistance to at least 1 s-line drug. At t1, the frequency of RAM in patients with a lower adherence to pharmacy appointments (<95%) was significantly lower (12/20, 60% for NRTI and 14/20, 70% for NNRTI) than in those with a better adherence (26/28, 92.8% for NRTI and 25/28, 89.3% for NNRTI) (OR 0.12, 95% CI 0.02-0.63, p = 0.012 and OR 0.28, 95% CI 0.06-1.29, p = 0.103, respectively). Overall thymidine analogue mutations (TAMs) accumulation rate was 0.32/year, 0.50/year in the subgroup with HIV RNA >10,000 copies/mL; NNRTI RAM accumulation rate was 0.15/year, 0.40/year in the subgroup with HIV RNA >10,000 copies/mL.Conclusions: While the activity of NNRTIs is compromised early during failure, tenofovir and zidovudine activity are reduced more frequently after 1 year of documented virological failure of thymidine analogue-based first-line ART, with RAMs accumulating faster in patients with higher viral loads. The present observation may help informing decisions on when to switch to a second line ART in patients on virological failure in LMIC. [ABSTRACT FROM AUTHOR]

In this study, we analysed in a cohort of pregnant women followed for two years the proportion of women remaining at the same clinic, those who transferred to other clinics, and those lost to follow-up. The possible determinants of the loss to follow-up were also assessed in a setting of postpartum discontinuation based on CD4+ count. A total of 311 pregnant women received antiretroviral therapy from week 25 of gestational age until six months postpartum (end of breastfeeding period), or indefinitely if meeting the criteria for treatment (baseline CD4+ <350 cells/mm(3)). Twenty-four months after delivery, six women had died, 247 were in active follow-up, 21 had transferred to another antiretroviral therapy clinic and 37 were lost to follow-up (rate of loss to follow-up 13%, 95% CI 9.1-16.9%). The presence of a baseline CD4+ count above 350 cells/mm(3) was associated with a ten-fold higher risk of loss to follow-up after six months of delivery (hazard ratio: 9.8, 95% CI 2.2-42.7, for baseline CD4 >350 cells/mm(3) versus baseline CD4+ count below 350 cells/mm(3), p = 0.002). This finding suggests that discontinuation of drugs when the risk of transmission has ceased can have a negative impact on the retention in care of these women. [ABSTRACT FROM AUTHOR]