Recent HIV infections: evaluation of a simple identification score for newly diagnosed patients

ABSTRACT OBJECTIVE Recognize incident infection to better characterize the groups that fuel HIV epidemic. We propose a simple score to identify recent infections among newly diagnosed patients as a HIV surveillance tool. METHODS Newly diagnosed patients were defined as recent infections when a negative serological test in the previous year was available. Laboratory tests, such as the avidity index (Bio-Rad, according to the CEPHIA protocol), chemiluminescent intensity (CMIA, architect, Abbott), and the nucleotide ambiguity index of partial pol sequences were used as proxies of recency. A simple score based on clinical symptoms of acute retroviral syndrome during the previous year, CD4+ T cell count, and viral load at admission was tested to assess the predictive power, using receiver operating characteristic (ROC) curves, to identify recent cases of infection. RESULTS We evaluated 204 recently diagnosed patients who were admitted to the Ambulatório de Referência em Moléstias Infecciosas de Santo André (Santo André Reference Infectious Diseases Outpatient Clinic), in the metropolitan region of São Paulo, Brazil, recruited between 2011 and 2018. An HIV-negative test in the year prior to enrollment was documented in 37% of participants. The proportion of cases classified as recent infections (less than one year), according to the laboratory proxies were: 37% (67/181) for an avidity index < 40%, 22% (30/137) for a CMIA < 200, and 68% (124/181) for an ambiguity index < 0.5%. Using different combinations of recency definitions, our score showed an area under the ROC curve from 0.66 to 0.87 to predict recency. CONCLUSIONS Using data from patients' interviews and routine laboratory tests at admission, a simple score may provide information on HIV recency and thus, a proxy for HIV incidence to guide public policies. This simple for the Brazilian public health system and other low- and middle-income countries.

SARS-CoV-2 testing among patients and healthcare professionals in an HIV outpatient clinic in Brazil

ABSTRACT The COVID-19 pandemic in Brazil has been marked by high infection and death rates. The immune response generated by current vaccination might be influenced by previous natural infection, and baseline estimates may help in the evaluation of vaccine-induced serological response. We evaluated previous SARS-CoV-2 testing (RT-PCR), and performed rapid diagnostic tests (RDT) and high throughput electrochemiluminescence immunoassay (ECLIA) before vaccination among people living with HIV (PLWH), users of antiretroviral prophylaxis (PrEP/PEP), and healthcare professionals in an HIV outpatient clinic (HCP-HC). RDT was positive in 25.7% (95% CI: 19-33%) overall, 31.3% (95% CI : 18-45%) among PLWH, 23.7% (95% CI : 14-34%) in PrEP/PEP users and 21.4% (95% CI : 05-28%) in HCP-HC (p=0.548). Diagnostic RT-PCR testing was very limited, even for symptomatic individuals, and whereas all HCP-HC had one test perfomed, only 35% of the patients (PREP/PEP/PLWH) were tested (p<0.0001). Adequate monitoring of post-vaccination humoral response and breakthrough infections including those in asymptomatic cases are warranted, especially in immunologically compromised individuals.

Field evaluation of COVID­19 antigen tests versus RNA based detection: Potential lower sensitivity compensated by immediate results, technical simplicity, and low cost

One year into the coronavirus disease 2019 (COVID­19) pandemic, diagnosticstrategies, although central for contact tracing and other preventive measures, arestill limited. To meet the global demand, lower cost and faster antigen tests forsevere acute respiratory syndrome coronavirus 2 (SARS­CoV­2) detection are aconvenient alternative to the gold standard reverse transcription­polymerase chainreaction (RT­PCR) assay. We tested laboratory­based RT­PCR RNA detection andtwo rapid antigen detection (RAD) tests, based on the immunochromatography testfor nucleocapsid protein of SARS­CoV­2 (COVID­19 Ag ECO Test, ECO Diagnóstica,and Panbio COVID­19 Ag Rapid Test Abbott). Paired collection and testing weredone in a small prospective open study in three clinical services in São Paulo,constituted of mostly symptomatic volunteers at collection (97%, 109/112) for amedian of 4 days (interquartile range: 3­6), ranging from 1 to 30. Among the108 paired RT­PCR/RAD tests, results were concordant in 96.4% (101/108). Thetest's performance was comparable, with an overall sensitivity of 87% and aspecificity of 96%. These observations add to other data that suggest that antigentests may provide reasonable sensitivity and specificity and deserve a role toimprove testing strategies, especially in resource­limited settings.

Impacto do uso da reação em cadeia da polimerase para o diagnóstico de meningite bacteriana em substituição a contraimunoeletroforese / Impact of using polymerase chain reaction for the diagnosis of bacterial meningitis in substitution for counterimmunoelectrophoresis

Introdução: a meningite bacteriana é um grave problema de Saúde Pública mundial, tendo como principais agentes: Neisseria meningitidis, Streptococcus pneumoniae e Haemophilus influenzae. A metodologia de diagnóstico empregada no Instituto Adolfo Lutz ­ Centro de Laboratório Regional Santo André até o ano de 2011 era a contraimunoeletroforese (CIE), depois foi substituída pela reação em cadeia da polimerase em tempo real (qPCR), que apresenta maior sensibilidade. Objetivo: este trabalho objetivou comparar ambas as metodologias no período de 2009 a 2018, para avaliação do impacto da introdução da qPCR no diagnóstico das meningites bacterianas nos 7 municípios da região do ABC do Estado de São Paulo. Metodologia: foram avaliadas a quantidade total de exames realizados, a média mensal, a positividade no período, os municípios requisitantes e a prevalência das bactérias causadoras de meningite, no período de abril/2009 até dezembro/2018. Resultados: Foram 377 exames de CIE e 1305 de qPCR, com média anual de 230 exames em 2010-2013 e 130 exames em 2014-2018. Observou-se aumento da positividade entre as técnicas, 17,8% para CIE e 33,8% para qPCR. N. meningitidis foi responsável pela maioria dos casos entre 2011 e 2013, cerca de 61% dos casos positivos, enquanto que entre 2014 e 2018 foi S. pneumoniae, cerca de 53%. Conclusão: os resultados indicaram que a qPCR foi mais eficiente em detectar os agentes causadores de meningite bacteriana na região do que a técnica de CIE. Por fim, este trabalho suporta a implantação da metodologia de qPCR para diagnóstico de meningite em substituição de técnicas menos sensíveis.

Introduction: bacterial meningitis is still a serious worldwide public health problem, and the main etiological agents are: Neisseria meningitidis, Streptococcus pneumoniae and Haemophilus influenzae. The diagnostic methodology employed at the Adolfo Lutz Institute ­ Santo André Regional Laboratory Center until 2011 was the ounterimmunoelectrophoresis (CIE), then it was replaced by the real-time polymerase chain reaction (qPCR), which is more sensitivity. Objective: this study aimed to compare both methodologies from 2009 to 2018 to evaluate the impact of the introduction of qPCR in the diagnosis of bacterial meningitis in the 7 cities of the ABC region of São Paulo State. Methodology: the total number of tests performed, the month average, the positivity in the period, the requesting cities and the prevalence of bacteria causing meningitis were evaluated from April/2009 to December/2018. Results: there were 377 CIE exams and 1305 qPCR exams, with an annual average of 230 exams in 2010-2013 and 130 exams in 2014-2018. There was an increase in positivity between the performed techniques, 17.8% for CIE and 33.8% for qPCR. N. meningitidis accounted for most cases of bacterial meningitis between 2011 and 2013, about 61% of positive cases, whereas between 2014 and 2018 it was S. pneumoniae, with about 53%. Conclusion: the results indicated that qPCR was more efficient in detecting the agents that cause bacterial meningitis in the region than the CIE technique. Finally, this work supports the implementation of qPCR methodology for diagnosis of meningitis in replacement of less sensitive techniques.