Search

This document is a response letter to the editor of the Revista Paulista de Pediatria. The authors express gratitude for the appreciation of their article on human adenovirus associated with severe cold agglutinin syndrome in pediatrics. They address concerns raised by specialists regarding the immunohematological evaluation and diagnosis of Cold Agglutinin Syndrome (CAS). The authors provide detailed results of their studies and explain that the technique for testing antibody titers was not available in their laboratory. They also discuss the use of therapeutic plasma exchange (TPE) as a temporary measure in severe cases of pediatric CAS secondary to infection. The authors acknowledge that more effective therapies for CAS are available for adults but not for pediatric patients. They thank the specialists for their comments and provide references for further reading on the topic. [Extracted from the article]

The development of alloantibodies or autoantibodies is a complication observed in sickle cell disease. Autoimmunization occurs in 7.6-12% of chronically or intermittently transfused patients with sickle cell disease; however, the clinical implications of autoAbs are unclear. Few studies have focused on pediatric sickle cell disease and autoimmune hemolytic anemia. Herein, we present the coexistence of sickle cell disease and autoimmune hemolytic anemia in two adolescent patients, focusing on their pathophysiology, diagnosis, clinical management, and outcomes. [ABSTRACT FROM AUTHOR]

This study assessed the technical performance of a rapid lateral flow immunochromatographic assay (LFIA) for the detection of anti-SARS-CoV-2 IgG and compared LFIA results with chemiluminescent immunoassay (CLIA) results and an in-house enzyme immunoassay (EIA). To this end, a total of 216 whole blood or serum samples from three groups were analyzed: the first group was composed of 68 true negative cases corresponding to blood bank donors, healthy young volunteers, and eight pediatric patients diagnosed with other coronavirus infections. The serum samples from these participants were obtained and stored in a pre-COVID-19 period, thus they were not expected to have COVID-19. In the second group of true positive cases, we chose to replace natural cases of COVID-19 by 96 participants who were expected to have produced anti-SARS-CoV-2 IgG antibodies 30-60 days after the vaccine booster dose. The serum samples were collected on the same day that LFIA were tested either by EIA or CLIA. The third study group was composed of 52 participants (12 adults and 40 children) who did or did not have anti-SARS-CoV-2 IgG antibodies due to specific clinical scenarios. The 12 adults had been vaccinated more than seven months before LFIA testing, and the 40 children had non-severe COVID-19 diagnosed using RT-PCR during the acute phase of infection. They were referred for outpatient follow-up and during this period the serum samples were collected and tested by CLIA and LFIA. All tests were performed by the same healthcare operator and there was no variation of LFIA results when tests were performed on finger prick whole blood or serum samples, so that results were grouped for analysis. LFIA's sensitivity in detecting anti-SARS-CoV-2 IgG antibodies was 90%, specificity 97.6%, efficiency 93%, PPV 98.3%, NPV 86.6%, and likelihood ratio for a positive or a negative result were 37.5 and 0.01 respectively. There was a good agreement (Kappa index of 0.677) between LFIA results and serological (EIA or CLIA) results. In conclusion, LFIA analyzed in this study showed a good technical performance and agreement with reference serological assays (EIA or CLIA), therefore it can be recommended for use in the outpatient follow-up of non-severe cases of COVID-19 and to assess anti-SARS-CoV-2 IgG antibody production induced by vaccination and the antibodies decrease over time. However, LFIAs should be confirmed by using reference serological assays whenever possible.