B and T cell responses to the 3rd and 4th dose of the BNT162b2 vaccine in dialysis patients

Patients on dialysis (PoD) are at high risk of severe morbidity and mortality from COVID-19. Characterizing long-term vaccine immune responses in these patients will help optimize vaccine schedule for PoD. This study aimed to determine whether long-term humoral and B and T cell-responses post 3rd and 4th dose of the BNT162b2 vaccine differed between PoD and controls. Non-infected PoD and controls vaccinated with BNT162b2 were recruited in Ziv Medical Center, Israel, between 2021 and 2022. Specimens were collected 1-2 months pre 3rd dose; 1-3 months post 3rd dose; 4-5 months post 3rd dose and 3-5 months post the 4th dose. Anti-SARS-CoV-2 spike (spike) specific antibodies, spike specific memory B cells, and spike specific CD154+ T cells as well as cytokines producing CD4+/CD8+ T cells were measured using standardized assays and compared between PoD and controls at each time point using Mann Whitney and Fisher's exact tests. We recruited 22 PoD and 20 controls. Antibody levels in PoD were lower compared to controls pre 3rd dose but not post 3rd and 4th doses. Frequencies of spike specific memory B cell populations were similar between PoD and controls overall. Frequencies of spike specific T cells, including those producing IFNγ and TNFα, were not lower in PoD. B and T cell mediated immune response in PoD following a 3rd and a 4th dose of the BNT162b2 vaccine was not inferior to controls up to 5 months post vaccination. Our results suggest that standard BNT162b2 vaccination is suitable for this group.

Genetic Markers Among the Israeli Druze Minority Population With End-Stage Kidney Disease

RATIONALE & OBJECTIVE

Genetic etiologies have been identified among approximately 10% of adults with chronic kidney disease (CKD). However, data are lacking regarding the prevalence of monogenic etiologies especially among members of minority groups. This study characterized the genetic markers among members of an Israeli minority group with end-stage kidney disease (ESKD).

STUDY DESIGN

A national-multicenter cross-sectional study of Israeli Druze patients (an Arabic-speaking Near-Eastern transnational population isolate) who are receiving maintenance dialysis for ESKD. All study participants underwent exome sequencing.

SETTING & PARTICIPANTS

We recruited 94 adults with ESKD, comprising 97% of the total 97 Druze individuals throughout Israel being treated with dialysis during the study period.

PREDICTORS

Demographics and clinical characteristics of kidney disease.

OUTCOME

Genetic markers.

ANALYTICAL APPROACH

Whole-exome sequencing and the relationship of markers to clinical phenotypes.

RESULTS

We identified genetic etiologies in 17 of 94 participants (18%). None had a previous molecular diagnosis. A novel, population-specific, WDR19 homozygous pathogenic variant (p.Cys293Tyr) was the most common genetic finding. Other monogenic etiologies included PKD1, PKD2, type IV collagen mutations, and monogenic forms of noncommunicable diseases. The pre-exome clinical diagnosis corresponded to the final molecular diagnosis in fewer than half of the participants.

LIMITATIONS

This study was limited to Druze individuals, so its generalizability may be limited.

CONCLUSIONS

Exome sequencing identified a genetic diagnosis in approximately 18% of Druze individuals with ESKD. These results support conducting genetic analyses in minority populations with high rates of CKD and for whom phenotypic disease specificity may be low.

PLAIN-LANGUAGE SUMMARY

Chronic kidney disease (CKD) affects many people worldwide and has multiple genetic causes. However, there is limited information on the prevalence of genetic etiologies, especially among minority populations. Our national-multicenter study focused on Israeli Druze patients. Using exome-sequencing, we identified previously undetected genetic causes in nearly 20% of patients, including a new and population-specific WDR19 homozygous pathogenic variant. This mutation has not been previously described; it is extremely rare globally but is common among the Druze, which highlights the importance of studying minority populations with high rates of CKD. Our findings provide insights into the genetic basis of end-stage kidney disease in the Israeli Druze, expand the WDR19 phenotypic spectrum, and emphasize the potential value of genetic testing in such populations.

Acute Kidney Injury and Hair-Straightening Products: A Case Series

RATIONALE & OBJECTIVE

Keratin-based hair-straightening treatment is a popular hair-styling method. The majority of keratin-based hair-straightening products in Israel contain glycolic acid derivatives, which are considered safe when used topically. Systemic absorption of these products is possible, and anecdotal reports have described kidney toxicity associated with their use. We report a series of cases of severe acute kidney injury (AKI) following use of hair-straightening treatment in Israel during the past several years.

STUDY DESIGN

Case series.

SETTING & PARTICIPANTS

We retrospectively identified 26 patients from 14 medical centers in Israel who experienced severe AKI and reported prior treatment with hair-straightening products in 2019-2022.

FINDINGS

The 26 patients described had a median age of 28.5 (range, 14-58) years and experienced severe AKI following a hair-straightening procedure. The most common symptoms at presentation were nausea, vomiting, and abdominal pain. Scalp rash was noted in 10 (38%) patients. Two patients experienced a recurrent episode of AKI following a repeat hair-straightening treatment. Seven patients underwent kidney biopsies, which demonstrated intratubular calcium oxalate deposition in 6 and microcalcification in tubular cells in 1. In all biopsies, signs of acute tubular injury were present, and an interstitial infiltrate was noted in 4 cases. Three patients required temporary dialysis.

LIMITATIONS

Retrospective uncontrolled study, small number of kidney biopsies.

CONCLUSIONS

This series describes cases of AKI with prior exposure to hair-straightening treatments. Acute oxalate nephropathy was the dominant finding on kidney biopsies, which may be related to absorption of glycolic acid derivatives and their metabolism to oxalate. This case series suggests a potential underrecognized cause of AKI in the young healthy population. Further studies are needed to confirm this association and to assess the extent of this phenomenon as well as its pathogenesis.

Effects of hemodialysis with cooled dialysate on high-sensitivity cardiac troponin I and brain natriuretic peptide

BACKGROUND

Hemodialysis (HD) triggers recurrent and cumulative ischemic insults to the brain and the heart. Cooled dialysate may have a protective effect on major organs and improve hemodynamic tolerability of dialysis. The aim of the study was to compare HD with cooled dialysate with routine dialysis in terms of hemodynamic stability and levels of high-sensitivity Troponin I (hs-TnI) and N-terminal pro b-type natriuretic peptide (NTproBNP) pre and postdialysis.

METHODS

The 45 patients were randomized into two groups. The first group received a 35.5°C dialysate first (hypothermic dialysis) and the second group a 36.5°C dialysate first (routine dialysis). Then groups crossed over, so each group received the alternate dialysate (self-controls) For each patient, the first sample was collected at the beginning of dialysis, and a second sample was taken at the end of dialysis.

RESULTS AND CONCLUSION

hs-TnI and NTproBNP increased after routine HD by 10.7 ng\ml (p < 0.001) and (12.0 pg/μl) (p < 0.001), respectively, and by -3.1 ng\ml (p = 0.25) and (4.3 pg/μl) (p < 0.001), respectively after hypothermic HD. Our study results showed a tendency towards less rise in hsTnI and NTproBNP during hypothermic HD (35.5°C) as compared to routine HD (36.5°C). Neither arm experienced statistically significant changes in blood pressure. Further studies in larger cohorts and long follow up are warranted in order to confirm that lower rise in (hs-TnI) and NTproBNP actually translate into lower clinical risk for cardiovascular events.

MO046: Exome sequencing of Israeli Druze individuals on dialysis reveals common as well as population- specific monogenic etiologies in ∼30%

BACKGROUND AND AIMS

Genetic etiologies are estimated to affect ∼10% of adults with advanced CKD. However, significant population disparities in genetic kidney disease exist and population-based screening are lacking especially among minority groups. The Druze population is a middle-eastern minority with high rates of end-stage renal disease (ESRD) and consanguinity, which suggests high rates of population-specific monogenic CKD etiologies. We therefore hypothesized that by exome sequencing we will identify a unique distribution of monogenic ESRD causes as compared with prior studies and that important ramifications for clinical practice may ensue.

METHOD

We initiated a national multicenter study of all Israeli dialysis units in order to provide comprehensive evidence for ESRD's genetic basis (Israeli ESRD Genetic Consortium Cohort). Specifically, during 2020, we recruited 97% (n = 94) of Israeli Druze individuals on dialysis from 12 different hospitals and community-based units. We conducted exome sequencing and diagnostic analysis for all patients. We assessed the diagnostic yield of genetic analysis and its relation to baseline clinical phenotypes.

RESULTS

Overall, the cohort consists of 94 individuals from 91 different families with first-degree consanguinity rate of 28%. Participants mean age was 62 years (ranging from 18 to 88 years). Most common primary clinical diagnoses were diabetic kidney disease, nephropathy of unknown origin, glomerular or cystic kidney disease, together encompassing 90% of all cases. None had previous molecular diagnosis. Using exome sequencing, we identified a genetic etiology in 27 out of 94 (28.7%) participants. We identified WDR19 (NPHP13) homozygous mutation c.878G &gt; A (p.C293Y) as the most common genetic diagnosis (5.3%). Follow-up clinical characterization revealed that all affected individuals exhibited non-syndromic adulthood-onset ESRD, supporting a profound mutation-dependent phenotypic heterogeneity and weak pre-exome phenotypic specificity. Other prevalent genetic diagnoses included type IV collagen, PKD1, PKD2 and UMOD mutations as well as monogenic forms of diabetes and hyperlipidemia. Molecular diagnosis corresponded to the pre-exome clinical diagnosis in only one-third of the participants.

CONCLUSION

Exome sequencing in Druze with ESRD yields a genetic diagnosis in just &lt;30% of cases with WDR19 mutation being the most prevalent single-gene etiology. These results, which remarkably inform clinical management, emphasize the importance of revealing population-specific mutations given the underutilization of genetic testing, particularly among adult minorities.

Antibody-mediated Immunogenicity against SARS-CoV-2 following priming, boosting and hybrid immunity: insights from 11 months of follow-up of a healthcare worker cohort in Israel, December 2020-October 2021

Background

We determined circulating anti-S severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin G (IgG) antibody titers in a vaccinated healthcare workers (HCWs) cohort from Northern Israel in the 11 months following primary vaccination according to age, ethnicity, and previous infection status.

Methods

All consenting HCWs were invited to have their IgG levels measured before vaccination and at 6 subsequent timepoints using a quantitative S1/S2 IgG assay. All HCWs with suspected coronavirus disease 2019 (COVID-19) were polymerase chain reaction (PCR) tested. We described trends in circulating IgG geometric mean concentration (GMC) by age, ethnicity, timing of boosting, and previous infection status and compared strata using Kruskall-Wallis tests.

Results

Among 985 vaccinated HCWs, IgG titers between 1 month post 2nd dose to pre-boosting gradually decreased in all age groups. Younger or previously infected individuals had higher initial post-vaccination IgG levels (P < .001 in both cases); differences substantially decreased or disappeared at 7–9 months, before boosting. The proportion of individuals infected prior to initiating vaccination and re-infected after dose 1 was comparable to the proportion of breakthrough infection post-dose 2 in those not previously infected (4.2 vs 4.7%). Pre-infection IgG levels in the 40 participants with breakthrough infection after dose 2 were similar to levels measured at the same timepoint in vaccinated HCWs who remained uninfected (P > .3). Post-dose3 IgG levels were more than 10-fold those 1 month post-dose 2.

Conclusions

Immunity waned in all age groups and previously infected individuals, reversed by boosting. IgG titers decrease and reinfections in individuals with hybrid immunity (infection + vaccination) suggests they may also require further doses. Our study also highlights the difficulty in determining protective IgG levels.

[HEMODIALYSIS: PRESENT INNOVATIONS FOR PATIENTS' FUTURE]

End-stage renal disease (ESRD) is a major cause of morbidity and mortality worldwide. Survival of ESRD patients depends on renal replacement therapies, such as kidney transplantation and dialysis. Due to the shortage of potential kidney donors and patients' comorbidities, dialysis is the major therapeutic option offered to such patients. In this review, recent advances in hemodialysis and hemodiafiltration, and their potential impact on improving patient survival will be discussed.