COVID-19 in Patients with Glomerular Disease: Follow-Up Results from the IRoc-GN International Registry
Authors: Waldman Meryl , Soler Maria Jose , García-Carro Clara , Lightstone Liz , Turner-Stokes Tabitha , Griffith Megan , Torras Joan , Martinez Valenzuela Laura , Bestard Oriol , Geddes Colin , Flossmann Oliver , Budge Kelly L. , Cantarelli Chiara , Fiaccadori Enrico , Delsante Marco , Morales Enrique , Gutierrez Eduardo , Niño-Cruz Jose A. , Martinez-Rueda Armando J. , Comai Giorgia , Bini Claudia , La Manna Gaetano , Slon Maria F. , Manrique Joaquin , Avello Alejandro , Fernandez-Prado Raul , Ortiz Alberto , Marinaki Smaragdi , Martin Varas Carmen Rita , Rabasco Ruiz Cristina , Sierra-Carpio Milagros , García-Agudo Rebeca , Fernández Juárez Gema , Hamilton Alexander J. , Bruchfeld Annette , Chrysochou Constantina , Howard Lilian , Sinha Smeeta , Leach Tim , Agraz Pamplona Irene , Maggiore Umberto , Cravedi Paolo 
Published: December 2021

Key Points

Mortality and incidence of AKI do not differ between coronavirus disease 2019 (COVID-19) patients with or without glomerular diseases.The main predictor of AKI is pre-COVID-19 eGFR, independent of the presence of GN.Incomplete kidney function recovery after COVID-19-associated AKI is more common in GN patients than in controls.

Background
The acute and long-term effects of severe acute respiratory syndrome coronavirus 2 infection in individuals with GN are still unclear. To address this relevant issue, we created the International Registry of COVID-19 infection in GN.

Methods
We collected serial information on kidney-related and -unrelated outcomes from 125 GN patients (63 hospitalized and 62 outpatients) and 83 non-GN hospitalized patients with coronavirus disease 2019 (COVID-19) and a median follow-up period of 6.4 (interquartile range 2.3–9.6) months after diagnosis. We used logistic regression for the analyses of clinical outcomes and linear mixed models for the longitudinal analyses of eGFR. All multiple regression models were adjusted for age, sex, ethnicity, and renin-angiotensin-aldosterone system inhibitor use.

Results
After adjustment for pre-COVID-19 eGFR and other confounders, mortality and AKI did not differ between GN patients and controls (adjusted odds ratio for AKI=1.28; 95% confidence interval [CI], 0.46 to 3.60; P=0.64). The main predictor of AKI was pre-COVID-19 eGFR (adjusted odds ratio per 1 SD unit decrease in eGFR=3.04; 95% CI, 1.76 to 5.28; P<0.001). GN patients developing AKI were less likely to recover pre-COVID-19 eGFR compared with controls (adjusted 6-month post-COVID-19 eGFR=0.41; 95% CI, 0.25 to 0.56; times pre-COVID-19 eGFR). Shorter duration of GN diagnosis, higher pre-COVID-19 proteinuria, and diagnosis of focal segmental glomerulosclerosis or minimal change disease were associated with a lower post-COVID-19 eGFR.

Conclusions
Pre-COVID-19 eGFR is the main risk factor for AKI regardless of GN diagnosis. However, GN patients are at higher risk of impaired eGFR recovery after COVID-19-associated AKI. These patients (especially those with high baseline proteinuria or a diagnosis of focal segmental glomerulosclerosis or minimal change disease) should be closely monitored not only during the acute phases of COVID-19 but also after its resolution.