Evaluation of four commercial virological assays for early infant HIV-1 diagnosis using dried blood specimens.

BACKGROUND: Early infant diagnosis (EID) of HIV-1 is necessary to reduce HIV-related mortality. As maternal antibodies transferred across the placenta may persist up to 18 mo, commercial virological assays (CVAs) are needed. This study compares four CVAs for EID using dried blood specimens (DBS) from HIV-1-exposed infants. METHODS: DBS from 68 infants born to HIV-1-infected women were collected from November 2012 to December 2013 in Equatorial Guinea. Four CVAs were performed: Siemens VERSANT HIV-1 RNA 1.0 kPCR assay, Roche CAP/CTM Quantitative Test v2.0, CAP/CTM Qualitative Tests v1.0 and v2.0. Definitive diagnosis was established following World Health Organization (WHO) recommendations. RESULTS: Two HIV-1-infected infants (2.9%) were detected by the four CVAs while 49 (72%) resulted negative. Discordant results were observed in 17 (25%) infants and HIV-1 infection was excluded in 14 patients when virological and serological testing was performed in additional DBS. Different false-positive rates HIV-1 were observed with Roche assays. CONCLUSION: CVAs using DBS were useful for EID, although discrepant results were common. Further research is required to reduce false-positive results that could result in wrong diagnosis and unneeded treatment. We propose caution with low viral load (VL) values when using VL assays. Clear guidelines are required for EID of HIV-exposed infants with discrepant virological results.

HIV-1 Variants and Drug Resistance in Pregnant Women from Bata (Equatorial Guinea): 2012-2013.

OBJECTIVES: This is the first study describing drug resistance mutations (DRM) and HIV-1 variants among infected pregnant women in Equatorial Guinea (GQ), a country with high (6.2%) and increasing HIV prevalence. METHODS: Dried blood spots (DBS) were collected from November 2012 to December 2013 from 69 HIV-1 infected women participating in a prevention of mother-to-child transmission program in the Hospital Regional of Bata and Primary Health Care Centre María Rafols, Bata, GQ. The transmitted (TDR) or acquired (ADR) antiretroviral drug resistance mutations at partial pol sequence among naive or antiretroviral therapy (ART)-exposed women were defined following WHO or IAS USA 2015 lists, respectively. HIV-1 variants were identified by phylogenetic analyses. RESULTS: A total of 38 of 69 HIV-1 specimens were successfully amplified and sequenced. Thirty (79%) belonged to ART-experienced women: 15 exposed to nucleoside reverse transcriptase inhibitors (NRTI) monotherapy, and 15 to combined ART (cART) as first regimen including two NRTI and one non-NRTI (NNRTI) or one protease inhibitor (PI). The TDR rate was only found for PI (3.4%). The ADR rate was 37.5% for NNRTI, 8.7% for NRTI and absent for PI or NRTI+NNRTI. HIV-1 group M non-B variants caused most (97.4%) infections, mainly (78.9%) recombinants: CRF02_AG (55.2%), CRF22_A101 (10.5%), subtype C (10.5%), unique recombinants (5.3%), and A3, D, F2, G, CRF06_cpx and CRF11_cpx (2.6% each). CONCLUSIONS: The high rate of ADR to retrotranscriptase inhibitors (mainly to NNRTIs) observed among pretreated pregnant women reinforces the importance of systematic DRM monitoring in GQ to reduce HIV-1 resistance transmission and to optimize first and second-line ART regimens when DRM are present.

Diagnóstico precoz de la infección por el virus de la inmunodeficiencia humana-1 en niños: programa de prevención de la transmisión maternoinfantil en Guinea Ecuatorial / Early diagnosis of human immunodeficiency virus-1 in infants: The prevention of mother-to-child transmission program in Equatorial Guinea

ANTECEDENTES: En los últimos años se han realizado grandes esfuerzos en el programa de prevención de la transmisión de la madre al hijo (PTMH) de VIH en Guinea Ecuatorial (GE). El objetivo de este estudio fue describir los resultados del programa de PTMH en 2 centros sanitarios de Guinea Ecuatorial. MÉTODOS: Estudio observacional prospectivo realizado en el Hospital Regional de Bata y Centro de Salud María Rafols en Bata, GE. Se analizaron las características epidemiológicas, clínicas y microbiológicas de las madres infectadas por el VIH-1 y de sus hijos. Se recogieron muestras sanguíneas en papel de filtro (DBS) en los lactantes expuestos (noviembre de 2012-diciembre de 2013) y se analizaron con la técnica Siemens VERSANT HIV-1 RNA v1.0 (kPCR). RESULTADOS: Sesenta y ocho pares de madres y niños fueron incluidos. La mayoría de las mujeres estaban asintomáticas (88,2% con estadio clínicoI de la OMS). Cuarenta y siete mujeres (69,2%) recibieron tratamiento antirretroviral durante el embarazo. Cuarenta y cinco niños (66,1%) recibieron profilaxis posnatal con antirretrovirales. La mediana de edad en el momento de inclusión fue de 2,4meses (rango 1,2-4,9). Se confirmó la infección en 2 niños, y un niño falleció antes de poder descartarse la infección. La tasa de transmisión del VIH-1 fue del 2,9% (IC95%: 0,2-10,5). CONCLUSIONES: Este estudio ha permitido evaluar el programa de PTMH en base a las técnicas de diagnóstico precoz. La identificación precoz de los pacientes infectados por el VIH-1 es fundamental para el inicio oportuno del tratamiento y evitar la mortalidad asociada a la infección

BACKGROUND: Great efforts have been made in the last few years in order to implement the prevention of mother-to-child transmission (PMTCT) program in Equatorial Guinea (GQ). The aim of this study was to evaluate the rates of mother-to-child HIV transmission based on an HIV early infant diagnosis (EID) program. METHODS: A prospective observational study was performed in the Regional Hospital of Bata and Primary Health Care Centre Maria Rafols, Bata, GQ. Epidemiological, clinical, and microbiological characteristics of HIV-1-infected mothers and their exposed infants were recorded. Dried blood spots (DBS) for HIV-1 EID were collected from November 2012 to December 2013. HIV-1 genome was detected using Siemens VERSANT HIV-1 RNA 1.0 kPCR assay. RESULTS: Sixty nine pairs of women and infants were included. Sixty women (88.2%) had WHO clinical stage 1. Forty seven women (69.2%) were on antiretroviral treatment during pregnancy. Forty five infants (66.1%) received postnatal antiretroviral prophylaxis. Age at first DBS analysis was 2.4 months (IQR 1.2-4.9). One infant died before a HIV-1 diagnosis could be ruled out. Two infants were HIV-1 infected and started HAART before any symptoms were observed. The rate of HIV-1 transmission observed was 2.9% (95%CI 0.2-10.5). CONCLUSIONS: The PMTCT rate was evaluated for the first time in GQ based on EID. EID is the key for early initiation of antiretroviral therapy and to reduce the mortality associated with HIV infection

[Early diagnosis of human immunodeficiency virus-1 in infants: The prevention of mother-to-child transmission program in Equatorial Guinea]. / Diagnóstico precoz de la infección por el virus de la inmunodeficiencia humana-1 en niños: programa de prevención de la transmisión maternoinfantil en Guinea Ecuatorial.

BACKGROUND: Great efforts have been made in the last few years in order to implement the prevention of mother-to-child transmission (PMTCT) program in Equatorial Guinea (GQ). The aim of this study was to evaluate the rates of mother-to-child HIV transmission based on an HIV early infant diagnosis (EID) program. METHODS: A prospective observational study was performed in the Regional Hospital of Bata and Primary Health Care Centre Maria Rafols, Bata, GQ. Epidemiological, clinical, and microbiological characteristics of HIV-1-infected mothers and their exposed infants were recorded. Dried blood spots (DBS) for HIV-1 EID were collected from November 2012 to December 2013. HIV-1 genome was detected using Siemens VERSANT HIV-1 RNA 1.0 kPCR assay. RESULTS: Sixty nine pairs of women and infants were included. Sixty women (88.2%) had WHO clinical stage 1. Forty seven women (69.2%) were on antiretroviral treatment during pregnancy. Forty five infants (66.1%) received postnatal antiretroviral prophylaxis. Age at first DBS analysis was 2.4 months (IQR 1.2-4.9). One infant died before a HIV-1 diagnosis could be ruled out. Two infants were HIV-1 infected and started HAART before any symptoms were observed. The rate of HIV-1 transmission observed was 2.9% (95%CI 0.2-10.5). CONCLUSIONS: The PMTCT rate was evaluated for the first time in GQ based on EID. EID is the key for early initiation of antiretroviral therapy and to reduce the mortality associated with HIV infection.

HIV-1 variability and viral load technique could lead to false positive HIV-1 detection and to erroneous viral quantification in infected specimens.

OBJECTIVES: Viral load (VL) testing is used for early HIV diagnosis in infants (EID) and for detecting early therapeutic failure events, but can be affected by HIV genetic variability. Dried blood samples (DBS) increase VL access and EID in remote settings and when low blood volume is available. METHODS: This study compares VL values using Siemens VERSANT HIV-1 RNA 1.0 kPCR assay (kPCR) and Roche CAP/CTM Quantitative test v2.0 (CAP/CTM v2.0) in 176 DBS carrying different HIV-1 variants collected from 69 Equatoguinean mothers and their infants with known HIV-1 status (71 infected, 105 uninfected). RESULTS: CAP/CTM v2.0 provided false positive VLs in 11 (10.5%) cases. VL differences above 0.5 log10 were observed in 42/49 (87.5%) DBS, and were above 1 log10 in 18 cases. CAP/CTM v2.0 quantified all the 41 specimens with previously inferred HIV-1 variant by phylogenetic analysis (68.3% recombinants) whereas kPCR only identified 90.2% of them, and was unable to detect 14.3% of 21 CRF02_AG viruses. CAP/CTM v2.0 showed higher sensitivity than kPCR (95.8% vs. 70.1%), quantifying a higher rate of viruses in infected DBS from subjects under antiretroviral exposure at sampling time compared to kPCR (94.7% vs. 96.2%, p-value<0.001). kPCR showed maximum specificity (100%) whereas for CAP/CTM v2.0 was 89.5%. CONCLUSIONS: VL assays should increase their sensitivity and specificity to avoid overestimated HIV-1 quantifications, which could be interpreted as virological failure events, or false negative diagnostic results due to genetic variability. We recommend using the same VL technique for each patient during antiretroviral therapy monitoring.

HIV-1 infection using dried blood spots can be confirmed by Bio-Rad Geenius™ HIV 1/2 confirmatory assay.

BACKGROUND: Confirmatory assays for HIV diagnosis are not well implemented in low-income countries with limited infrastructures. Geenius™ HIV 1/2 Confirmatory Assay is a single-use immunochromatographic test for the confirmation and differentiation of individual HIV-1/2 antibodies validated in venous whole blood, serum and plasma. However, dried blood specimens (DBS) are easier to collect, store and transport than plasma/serum in remote settings from limited resource countries and mobile populations. OBJECTIVES: To evaluate the confirmatory assay Geenius™ HIV 1/2 for HIV diagnosis using DBS specimens. STUDY DESIGN: We collected DBS from 70 Guinean women previously diagnosed as HIV-1 infected by rapid tests using whole blood samples in Equatorial Guinea and from 25 HIV-negative Guinean women and HIV-exposed infants diagnosed by molecular testing in Madrid. Geenius HIV 1/2 was performed by eluting two drops of dried blood from each patient and following the manufacturer instructions for the assay but using 40µl of the eluted blood as specimen. The results obtained were confirmed by western blot. RESULTS: Geenius™ HIV 1/2 successfully confirmed the HIV-1 positive and negative infection in all tested DBS specimens, providing 100% specificity [95% Confidence Interval (CI): 86.2%-100%]. No HIV 1/2 coinfections were found in the study cohort. This is the first report that proves a good performance of Geenius™ HIV 1/2 for the HIV-1 infection confirmation using only two drops of dried blood. CONCLUSIONS: Our results approve the utility of this confirmatory assay using DBS when a lack of adequate infrastructure to collect, store or transport plasma/serum is found. DBS are a practical alternative to plasma/serum for HIV serological diagnosis.