Association between Postmortem Kidney Biopsy Findings and Acute Kidney Injury from Patients with SARS-CoV-2 (COVID-19).

BACKGROUND AND OBJECTIVES: AKI 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, & MEASUREMENTS: Our 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. RESULTS: A 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. CONCLUSIONS: A 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.

Acute kidney injury in pregnancy and the role of underlying CKD: a point of view from México.

The incidence of acute kidney injury in pregnancy (P-AKI) in developed countries is significantly lower than in developing ones, where it is estimated to range between 4 and 26%. Mortality in cases of P-AKI requiring dialysis is high, varying from 20 to 80%. In developing countries, clinical decisions are often based on the availability of services and not on needs. Prenatal surveillance in Mexico does not include serum creatinine, limiting the potential for early diagnosis of AKI and CKD and their differential diagnosis. There are few specialized centers for the care of a pregnancy complicated with kidney disease in Mexico. P-AKI superimposed on preexistent, and usually undiagnosed CKD, is common: in Guadalajara 10 out of the 27 patients with Stage 3-5 CKD or nephrotic proteinuria, that were followed in 2013-2015, required renal replacement therapy (RRT) in pregnancy; in the same period in Mexico City out of 18 patients with P-AKI requiring dialysis, 5 remained dialysis dependent, 3 started dialysis in the following year after their pregnancy and only 1 fully recovered renal function. The grim prognosis is exacerbated by the fact that 70% of Mexicans are not reimbursed for dialysis, and pregnancy-related coverage lasts for only 42 days after delivery. Perinatal results are no less troubling, as most patients with P-AKI give birth preterm to small or very small babies. While our data do not allow us to evaluate needs, they do make it possible to define the complexity of the problems faced in the care of P-AKI in Mexico. Early diagnosis of P-AKI and chronic kidney disease (CKD) is needed to protect mothers and children and the country urgently needs programs to enable it to fulfil the World Health Organization's imperative that we "make every mother and child count".