Lessons for the clinical nephrologist: lumasiran as the future cornerstone treatment for patients with primary hyperoxaluria type 1?

Primary hyperoxaluria type 1 (PH1)—OMIM #259900—is a rare recessive autosomal disorder caused by a deficiency of the liver peroxisomal enzyme alanine-glyoxylate-aminotransferase (AGT), which catalyzes the conversion of glyoxylate to glycine. Reduced AGT activity leads to the conversion of glyoxylate to oxalate (Fig. 1). Oxalate forms insoluble calcium oxalate crystals that accumulate in the kidney and subsequently in other organs, when the kidneys are saturated, leading to systemic oxalosis [1]. The most severe PH1 cases start during the first months of life with rapid development of kidney failure [1]. Before 2020, treatment of PH1 mainly relied on supportive measures including intensive water intake, and on the prescription of vitamin B6 and oral crystallization inhibitors. Despite this, many patients still experience serious and life-threatening complications, especially end-stage kidney disease [1]. To date, PH1 patients with kidney failure can only be cured by dual liver-kidney transplantation with the well-known increased morbidity and mortality risks [2]. The following two cases describe the outcomes of two PH1 patients treated with lumasiran, a new innovative therapeutic approach

Analytical and clinical evaluation of new automated chemiluminescent immunoassays for the detection of IgG and IgM anti-Bartonella henselae antibodies.

Serological diagnosis of Bartonella henselae infection mainly rely on microscopic immunofluorescence assays (IFA), which are however time-consuming and poorly standardized. The aim of the study was to assess the use of the new fully automated VirClia® chemiluminescent immunoassays for the detection of IgG and IgM anti-B. henselae antibodies. Eighty-one patients with a well-defined B. henselae infection as well as 80 patients with an alternative disease were included. The VirClia® IgG antibody assay showed a sensitivity of 79.0% and a specificity of 93.8% for the diagnosis of B. henselae infection. For the VirClia® IgM assay, results were more conflicting with a sensitivity of 42.0% and a specificity of 98.2% to predict IFA IgM results. In 11 additional patients with uninterpretable IFA due to autoimmune antibodies, VirClia® assays were able to deliver valuable quantitative results. The VirClia® IgG assay shows good analytical and clinical performances and could be easily integrated in the diagnostic workflow of B. henselae infection

Low rates of humoral response to BNT162b2 SARS-CoV-2 vaccination in patients with immune-mediated kidney diseases treated with rituximab

N/

Co-infections in COVID-19 critically ill and antibiotic management: a prospective cohort analysis.

International guidelines recommend the initiation of empirical antibiotherapy for possible associated bacterial pneumonia in COVID-19 critically ill yet further suggesting a rapid reassessment upon source documentation [1]. In this prospective cohort analysis, we investigated the respiratory co-infection rate in COVID-19 critically ill through the use of rapid molecular testing and measured its impact on antibiotic management. [...

Usefulness of a multiplex immunodot in case of discordant results between automated COVID-19 serological assays.

At present, the only reliable test for COVID-19 diagnosis is RT-qPCR. Serological assays have been widely used to increase the detection sensitivity of infected population. Hereby, we report the performance of a new pan-IgG multiplex Enzyme Immunoassay (immunodot) method for exploration of discrepant SARS-COV-2 serological results. A retrospective study on 38 residual serum samples from recovered COVID-19 subjects with discordant serological results on Roche and Snibe platforms, were reanalyzed on a new semi-automated pan-IgG immunodot Enzyme Immunoassay, namely COVIDOT-TEST, in order to find the source of discrepancies and to evaluate the latter method. All samples were analyzed on the BlueDiver® Instrument and all strips were read by the BlueScan® Scanner using Dr DOT® Software. Based on our data, subject samples showed specific IgG reactions on ≥ 2 different antigens on immunodot strips. Of these 38 samples, 97.4% of samples showed specific IgG reaction against S1 + S2 antigens, 89.5% showed against RBD antigen, 86.8% against S2 antigen reaction on the COVIDOT-TEST kit. Specific IgG-S1 antigen and IgG-N antigen reactions were detected in 73.7% and 65.8% of the samples, respectively. The new semi-automated pan-IgG immunodot Enzyme Immunoassay method appeared to be a reliable assay to confirm suspicious COVID-19 serological screening results

Low performance of rapid antigen detection test as frontline testing for COVID-19 diagnosis.

Ensuring accurate diagnosis is essential to limit the spread of SARS-CoV-2 and for the clinical management of COVID-19. Although real-time reverse transcription polymerase chain reaction (RT- qPCR) is the current recommended laboratory method to diagnose SARS-CoV-2 acute infection, several factors such as requirement of special equipment and skilled staff limit the use of these time-consuming molecular techniques. Recently, several easy to perform rapid antigen detection tests were developed and recommended in some countries as the first line of diagnostic. The aim of this study was to evaluate the performances of the Coris COVID-19 Ag Respi-Strip test, a rapid immunochromatographic test for the detection of SARS-CoV-2 antigen, in comparison to RT-qPCR. 148 nasopharyngeal swabs were tested. Amongst the 106 positive RT-qPCR samples, 32 were detected by the rapid antigen test, given an overall sensitivity of 30.2%. All the samples detected positive with the antigen rapid test were also positive with RT-qPCR. Higher viral loads are associated with better antigen detection rates. Unfortunately, the overall poor sensitivity of the COVID-19 Ag Respi-Strip does not allow using it alone as the frontline testing for COVID-19 diagnosis