Background and objectivesAKI in coronavirus disease 2019 (COVID-19) is associated with higher morbidity and mortality. The objective of this study was to identify the kidney histopathologic characteristics of deceased patients with diagnosis of COVID-19 and evaluate the association between biopsy findings and clinical variables, including AKI severity.Design, setting, participants, & measurementsOur multicenter, observational study of deceased patients with COVID-19 in three third-level centers in Mexico City evaluated postmortem kidney biopsy by light and electron microscopy analysis in all cases. Descriptive and association statistics were performed between the clinical and histologic variables.ResultsA total of 85 patients were included. Median age was 57 (49–66) years, 69% were men, body mass index was 29 (26–35) kg/m2, 51% had history of diabetes, 46% had history of hypertension, 98% received anticoagulation, 66% were on steroids, and 35% received at least one potential nephrotoxic medication. Severe AKI was present in 54% of patients. Biopsy findings included FSGS in 29%, diabetic nephropathy in 27%, and arteriosclerosis in 81%. Acute tubular injury grades 2–3 were observed in 49%. Histopathologic characteristics were not associated with severe AKI; however, pigment casts on the biopsy were associated with significantly lower probability of kidney function recovery (odds ratio, 0.07; 95% confidence interval, 0.01 to 0.77). The use of aminoglycosides/colistin, levels of C-reactive protein and serum albumin, previous use of angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, antivirals, nonsteroid anti-inflammatory drugs, and anticoagulants were associated with specific histopathologic findings.ConclusionsA high prevalence of chronic comorbidities was found on kidney biopsies. Nonrecovery from severe AKI was associated with the presence of pigmented casts. Inflammatory markers and medications were associated with specific histopathologic findings in patients dying from COVID-19.

Introduction. Resilience consists of a series personalized skills to cope with adverse situations and overcome them, and even emerge strengthened. Resilience in patients with chronic renal insufficiency (CRI) treated with hemodialysis (HD) has been evaluated with general questionnaires that are not specific for this population. Objective. To evaluate the psychometric properties of a resilience questionnaire in patients treated with chronic HD. Method. The study included 280 patients with CRI (aged 18 to 85, 44% women) treated with HD for at least two months in six hemodialysis units in Mexico, who completed Beck’s depression and anxiety inventories, an inventory of cognitive distortions, and the Mexican Resilience Measurement Scale (RESI-M). Results. Owing to the duplication of more than one factor, two of the 43 items were eliminated in the exploratory factor analysis. We confirmed five factors that explained 63.4% of the total variance, with a Cronbach’s alpha of .96 (the alpha ranges in the five factors from .85 to .95). The confirmatory analysis showed a theoretical structural model that fits the empirical data in an acceptable, balanced, and parsimonious way. The five factors correlate positively with each other and negatively with anxiety and depression symptoms and distorted thoughts. Discussion and conclusion. The RESI-M scale is valid and reliable for assessing resilience in patients treated with chronic HD. Resilience factors evaluated with RESI-M are a potential therapeutic target to reduce depression and anxiety symptoms in these patients.

Background: Interstitial fibrosis (IF) on kidney biopsy is one of the most potent risk factors for kidney disease progression. The furosemide stress test (FST) is a validated tool that predicts the severity of acute kidney injury (especially at 2 h) in critically ill patients. Since furosemide is secreted through the kidney tubules, the response to FST represents the tubular secretory capacity. To our knowledge there is no data on the correlation between functional tubular capacity assessed by the FST with IF on kidney biopsies from patients with chronic kidney disease (CKD). The aim of this study was to determine the association between urine output (UO), Furosemide Excreted Mass (FEM) and IF on kidney biopsies after a FST. Methods: This study included 84 patients who underwent kidney biopsy for clinical indications and a FST. The percentage of fibrosis was determined by morphometry technique and reviewed by a nephropathologist. All patients underwent a FST prior to the biopsy. Urine volume and urinary sodium were measured in addition to urine concentrations of furosemide at different times (2, 4 and 6 h). We used an established equation to determine the FEM. Values were expressed as mean, standard deviation or percentage and Pearson Correlation. Results: The mean age of the participants was 38 years and 44% were male. The prevalence of diabetes mellitus, hypertension and diuretic use was significantly higher with more advanced degree of fibrosis. Nephrotic syndrome and acute kidney graft dysfunction were the most frequent indications for biopsy. eGFR was inversely related to the degree of fibrosis. Subjects with the highest degree of fibrosis (grade 3) showed a significant lower UO at first hour of the FST when compared to lower degrees of fibrosis (p = 0.015). Likewise, the total UO and the FEM was progressively lower with higher degrees of fibrosis. An inversely linear correlation between FEM and the degree of fibrosis (r = − 0.245, p = 0.02) was observed. Conclusions: Our findings indicate that interstitial fibrosis correlates with total urine output and FEM. Further studies are needed to determine if UO and FST could be a non-invasive tool to evaluate interstitial fibrosis. Trial registration: ClinicalTrials.gov NCT02417883.