Kinetics of Anti-SARS-CoV-2 IgG Antibodies in Hemodialysis Patients Six Months after Infection

BACKGROUND

The humoral response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the hemodialysis population, including its dynamics over time, remains poorly understood.

METHODS

To analyze initial and long-term humoral responses against SARS-CoV-2 in a hemodialysis population, we retrospectively evaluated findings from SARS-CoV-2 IgG serologic assays targeting the nucleocapsid antigen or spike antigen up to 6 months of follow-up in patients on hemodialysis in the Paris, France, region who had recovered from coronavirus disease 2019 (COVID-19).

RESULTS

Our analysis included 83 patients (median age 65 years); 59 (71%) were male and 28 (34%) had presented with severe COVID-19. We observed positive initial SARS-CoV-2 IgG antinucleocapsid serology in 74 patients (89%) at a median of 67 days postdiagnosis. By multivariable analysis, immunocompromised status was the only factor significantly associated with lack of an IgG antinucleocapsid antibody response. Follow-up data were available at 6 months postdiagnosis for 60 of 74 patients (81%) with positive initial antinucleocapsid serology, and 15 (25%) of them had negative antinucleocapsid serology at month 6. In total, 14 of 15 sera were tested for antispike antibodies, 3 of 14 (21%) of which were also negative. Overall, 97% of antinucleocapsid-antibody-positive specimens were also antispike-antibody positive. Female sex, age >70 years, and nonsevere clinical presentation were independently associated with faster IgG antinucleocapsid titer decay in multivariable analysis. After adjustment for sex and age >70 years, nonsevere clinical presentation was the only factor associated with faster decay of IgG antispike antibodies.

CONCLUSIONS

This study characterizes evolution of the SARS-CoV-2 antibody response in patients on hemodialysis and identifies factors that are associated with lack of seroconversion and with IgG titer decay.

COVID-19 chez les patients dialysés, expérience multicentrique en Île-de-France

Introduction

La pandémie de COVID-19 a été à l’origine d’une crise sanitaire sans précédent. Nous décrivons la présentation clinique, l’évolution et les facteurs pronostiques au sein d’une vaste cohorte de patients hémodialysés.

Description/Méthodes

Il s’agit d’une étude rétrospective de l’ensemble des patients COVID-19 diagnostiqués par PCR ou imagerie compatible dans dix-neuf centres de dialyse en Île-de-France entre le 5 février et le 1^er mai 2020. Nous rapportons l’évolution des patients à un mois. Les facteurs de risque de mortalité à la fin du suivi ont été déterminés par une régression logistique multivariée et l’effet des traitements a été analysé par score de propension.

Résultats

Une maladie COVID-19 a été diagnostiquée chez 248 patients (hommes 66 %, âge 67 ± 15 ans, ancienneté en dialyse de 5 ± 5 ans, suivi moyen de 39 ± 20 jours). La présentation clinique incluait fièvre (n = 152 ; 61 %), toux (n = 121 ; 49 %) et asthénie (n = 101 ; 41 %). Une diarrhée aiguë était présente dans 12 % des cas (n = 29). Cent quarante-deux patients (57 %) ont été hospitalisés et 46 sont décédés (mortalité globale 18 %, mortalité des hospitalisés 30 %). En analyse multivariée, un traitement immunosuppresseur (OR = 7,54 [2,39–24,96] ; p < 0,001) ; l’âge (OR = 1,06 [1,02–1,10] ; p = 0,002), ainsi que la dyspnée (OR = 2,9 [1,24–7,07] ; p = 0,014) étaient prédicteurs de la mortalité. La prescription d’hydroxychloroquine (avec ou sans azithromycine) (OR = 0,94 [0,38–2,09] ; p = 0,9) et les différents traitements antibiotiques n’étaient associés à aucune réduction significative de la mortalité.

Conclusion

Notre étude montre une mortalité importante des patients hémodialysés atteints de COVID-19. L’âge, le traitement immunosuppresseur et la présence d’une dyspnée étaient les prédicteurs indépendants du décès dans cette cohorte.

Characterization of the dynamics of human cytomegalovirus resistance to antiviral drugs by ultra-deep sequencing

Prophylactic or preemptive treatment strategies are required to prevent human cytomegalovirus (CMV) infections in transplant recipients. However, treatment failure occurs when CMV resistant-associated variants (RAVs) are selected. Although the diversity of CMV is lower than that of RNA viruses, CMV appears to show some genetic instability, with possible minor emerging resistance that may be undetectable by Sanger sequencing. We aimed to examine CMV-resistance mutations over time by ultra-deep sequencing (UDS) and Sanger sequencing in a kidney transplant recipient experiencing CMV infection. This patient showed a transient response to three different antiviral drugs (valganciclovir, foscarnet, and maribavir) and four episodes of CMV resistance over two years. The full-length UL97 (2.3kpb) and partial UL54 (2.4kpb) CMV genes were studied by UDS and Sanger sequencing and linkage mutations calculated to determine RAVs. We detected four major and five minor resistance mutations. Minor resistant variants (2-20%) were detected by UDS, whereas major resistance substitutions (>20%) were identified by both UDS and Sanger method. We detected cross-resistance to three drugs, despite high CMV loads, suggesting that the fitness of the viral mutants was not impaired. In conclusion, CMV showed complex dynamic of resistance under antiviral drug pressure, as described for highly variable viruses. The emergence of successive RAVs constitutes a clinically challenging complication and contributes to the difficulty of therapeutic management of patients.

Collapsing glomerulopathy associated lupus in a black female with homozygous APOL1 mutation

Collapsing glomerulopathy (CG), characterized by collapse of the glomerular capillary loops onto the mesangial stalks is rarely associated to systemic lupus erythematosus (SLE). Recently a genetic predisposition to HIV associated nephropathy (HIVAN) has been shown in Afro-Americans: MYH9 polymorhism in 2008 and then APOL1 variants (G1 and G2 alleles) in 2010 were shown to be strongly associated with HIVAN. We describe here for the first time the association of CG in a young Afro-American female with SLE having a homozygous mutation of APOL1. The clinical history, laboratory findings and immunofluorescence all confirmed a diagnosis of SLE. However, studies for factors associated with collapsing glomerulopathy in other situations were consistently negative. As this Afro-American patient developed a CG, we performed genotyping of APOL1. It was found that she is homozygotic for the G2 allele of APOL1. Despite.

Renal transplantation in patients with AA amyloidosis nephropathy: results from a French multicenter study

Although end-stage renal disease related to AA amyloidosis nephropathy is well characterized, there are limited data concerning patient and graft outcome after renal transplantation. We performed a multicentric retrospective survey to assess the graft and patient survival in 59 renal recipients with AA amyloidosis. The recurrence rate of AA amyloidosis nephropathy was estimated at 14%. The overall, 5- and 10-year patient survival was significantly lower for the AA amyloidosis patients than for a control group of 177 renal transplant recipients (p = 0.0001, 0.028 and 0.013, respectively). In contrast, we did not observe any statistical differences in the 5- and 10- year graft survival censored for death between two groups. AA amyloidosis-transplanted patients exhibited a high proportion of infectious complications after transplantation (73.2%). Causes of death included both acute cardiovascular events and fatal septic complications. Multivariate analysis demonstrated that the recurrence of AA amyloidosis on the graft (adjusted OR = 14.4, p = 0.01) and older recipient age (adjusted OR for a 1-year increase = 1.06, p = 0.03) were significantly associated with risk of death. Finally, patients with AA amyloidosis nephropathy are eligible for renal transplantation but require careful management of both cardiovascular and infectious complications to reduce the high risk of mortality.