We report on the development of nephrotic proteinuria and microhematuria, with histological features of renal thrombotic microangiopathy (TMA), following the first dose of BNT162b2 COVID-19 vaccine (Pfizer-BioNTech) and COVID-19 diagnosis. A 35-year-old previously healthy man was admitted at our hospital due to the onset of foamy urine. Previously, 40 days earlier, he had received the first injection of the vaccine, and 33 days earlier, the RT-PCR for SARS-CoV-2 tested positive. Laboratory tests showed nephrotic proteinuria (7.9 gr/day), microhematuria, serum creatinine 0.91 mg/dL. Kidney biopsy revealed ultrastructural evidence of severe endothelial cell injury suggestive of a starting phase of TMA. After high-dose steroid treatment administration, complete remission of proteinuria was achieved in a few weeks. The association of COVID-19 with renal TMA has been previously described only in patients with acute renal injury. Besides, the correlation with COVID-19 vaccine has not been reported so far. The close temporal proximity (7 days) between the two events opens the question whether the histological findings should be ascribed to COVID-19 itself or to vaccine injection.

Background: Despite the benefits of physical activity on cardiovascular risk in kidney transplant recipients (KTRs), the long-term effects of exercise have been poorly investigated. This is a three-year observational study comparing graft function and cardiovascular risk factors in active KTRs (AKTRs) vs. sedentary KTRs (SKTRs). Methods: KTRs with stable renal function were assigned to active or sedentary group in relation to the level of daily physical activity based on World Health Organization (WHO) recommendations (150 minutes/week, respectively). Complete blood count, renal function indices, lipid profile, blood pressure and anthropometric measures were collected yearly for an observation period of three years. The comparisons between the two groups were performed by repeated measures analyses of covariance (ANCOVAs), with age as a covariate. Results: Fifty-four subjects were included in the study. Thirty of them were identified as AKTRs (M/F 26/4, aged 45 ± 12 years) and 24 as SKTRs (M/F 18/6, aged 51 ± 14 years). Baseline characteristics were similar between the groups except body mass index (BMI) that was significantly higher in SKTRs (p = 0.043). Furthermore, over the three-year observation period, BMI decreased in AKTRs and increased in SKTRs (p = 0.006). Graft function was stable in AKTRs, while it showed a decline over time in SKTRs, as indicated by the rise in serum creatinine levels (p = 0.006) and lower eGFR (p = 0.050). Proteinuria, glucose and uric acid levels displayed a decrease in AKTRs and an increase in SKTRs during the three-year period (p = 0.015, p = 0.004 and p = 0.013, respectively). Finally, concerning lipid profiles, AKTRs had a significant reduction over time of triglycerides levels, which conversely showed a clinically relevant increase in SKTRs (p = 0.014). Conclusions: Our findings indicate that regular weekly exercise training may counteract the increased cardiovascular risks and also prevent graft function decline in KTRs.

Few solid-organ-transplanted patients (TP) perform regular sport activity. Poor data are available on the safety of intense and prolonged physical exercise on this population. The aim of the study was to evaluate kidney function parameters in a group of TP in comparison with healthy volunteers (HV) involved in a long-distance road cycling race: length 130 km and total uphill gradient, 1871 m. Nineteen TP were recruited: 10 renal, 8 liver, and 1 heart and compared with 35 HV. Renal function parameters, namely, creatinine, estimated glomerular filtration rate (eGFR), urea, uric acid, urine specific gravity, microalbuminuria, and proteinuria were collected and their values were compared the day before the race (T1), immediately after crossing the finish line (T2), and 18 to 24 hours after the competition (T3). No adverse events were recorded. At baseline, TP showed lower values of eGFR (69 ± 22 versus 87 ± 13 mL/min/1.73 m(2)), lower urine specific gravity (1015 ± 4 versus 1019 ± 6), and higher microalbuminuria (56 ± 74 versus 8 ± 15) and proteinuria values (166 ± 99 versus 74 ± 44) (in mg/L). At T2 in both groups, renal function parameters showed the same trends: decline of eGFR (54 ± 19 versus 69 ± 15 mL/min/1.73 m(2)) and rise in protein excretion. At T3, functional parameters returned to baseline, except for urine specific gravity values remaining stable in TP (1018 ± 6) and growing higher in HV (1028 ± 4). Selected and well-trained organ-transplanted patients can perform an intensive exercise, displaying temporary modifications on kidney function parameters comparable to healthy subjects, despite differences related to baseline clinical conditions and pharmacological therapies.