Kidney transplant patients (KT) are at high risk for severe COVID‐19 and presented attenuated antibody responses to vaccination when compared to immunocompetent individuals. Torquetenovirus (TTV) has recently gained attention as a potential surrogate marker of the net state of immunosuppression. We evaluated the association between pre‐vaccination TTV viral load and anti‐spike total antibody response to SARS‐CoV‐2 vaccination in KT.

*joint first authors 1 Nephrology Department, Hospital de Santa Cruz, Centro Hospitalar Lisboa Ocidental, Carnaxide, Portugal 2 Nephrology Department, Hospital do Divino Espírito Santo, Ponta Delgada, Portugal 3 Nephrology Department, Hospital de São Bernardo, Centro Hospitalar de Setúbal, Setúbal, Portugal 4 Nephrology Department, Hospital Curry Cabral, Centro Hospitalar Lisboa Central, Lisboa, Portugal

Introduction: Tubular damage is common in glomerular diseases (GD). Glycosuria is a marker of tubular dysfunction and may be used to detect tubular lesion and CKD progression. The aim of this study was to evaluate the prevalence and prognostic value of glycosuria at the time of diagnosis in primary glomerulopathies (PG). Methods: We conducted a 24-month retrospective study in patients diagnosed with PG in our center between 2009 and 2020. We excluded diabetic patients, use of SGLT2 inhibitors, transplant patients, and secondary GD. Patients were divided in two groups according to their glycosuria status at diagnosis. Results: We studied 115 patients. Global prevalence of glycosuria was 10% (n=11) and membranous nephropathy (MN) had the highest prevalence (n=5, 17.9%). We found that patients with glycosuria had higher serum creatinine (2.4 vs. 1.2 mg/dL, p=0.030), higher albuminuria (4.8 vs. 1.9 g/g, p=0.004), and lower serum albumin (2.3 vs. 3.2 g/dL, p=0.021). We did not find association with histological prognostic factors. At the end of follow-up, patients with glycosuria had higher prevalence of the composite outcome of stage 5D CKD or 50% increase in basal SCr (45.5% vs. 17.3%, p=0.037). In patients with MN, results were similar but we were able to find an association of glycosuria with more severe interstitial fibrosis and tubular atrophy (25.0 vs. 0.0 %, p=0.032). Conclusion: Ten percent of our patients with PG have glycosuria. Glycosuria at the time of diagnosis was associated with more severe clinical presentation and worst renal outcome. The association with higher albuminuria suggests that tubular function has an impact on the severity and outcomes of PG.

Renal artery thrombosis is a rare vascular event that precipitates renal infarction. Although in up to one third of cases the etiology is not identified, renal artery lesions, cardioembolism and acquired thrombophilias are the main causes. A bilateral simultaneous idiopathic renal artery thrombosis is an unlikely coincidence. We present two cases of patients with acute bilateral renal artery thrombosis of unknown etiology. Cardiac embolism, acquired thrombophilia and occult neoplasm workups were negative. Both cases were temporarily hemodialysis-dependent and partially recovered renal function under conservative approach with systemic anticoagulation. Recommendations on optimal treatment for renal artery thrombosis are still lacking. We discuss the available options.

INTRODUCTION:Few studies have investigated pre-donation factors that could affect renal recovery after living kidney donation (LKD). We retrospectively investigated the role of John Cunningham virus (JCV) infection and other pre-donation factors on the magnitude of kidney function decline after LKD.METHODS:Urine JCV viral loads, glomerular filtration rate, and blood pressure were evaluated in 60 consecutive LK donors before donation. Suboptimal compensatory hypertrophy was defined as an eGFR <60% of the pre-donation eGFR.RESULTS:LKD (40% JCV infected) were followed for 3.2±1.6 years. No association was found between age, gender, and baseline hypertension with 1st, 2nd, 3rd, and 4th years post-donation eGFR <60% of the pre-donation eGFR. Mean eGFR recovery at the 3rd year after donation was lower in JCV infected donors vs non-infected donors (61.8% vs 71.0%, p=0.006).CONCLUSION:We hypothesized that JCV could shift glomeruli into a hyperfiltration state before nephrectomy, modulating the magnitude of compensatory hypertrophy after donation. Conversely, JCV might curtail the ability of the remaining kidney to promote hyperfiltration. Longer follow up is needed to determine whether JCV viruria ultimately leads to lower eGFR over time or if it is a protective factor for the remaining kidney.

Thrombotic microangiopathy (TMA) is a rare disease that presents with haemolysis and organ damage. The kidney is one of the main affected organs, and TMA is associated with serious complications and increased mortality. In transplanted patients, TMA is even less common and has a variety of possible causes, including thrombotic thrombocytopenic purpura (TTP) and haemolytic-uremic syndrome (HUS), infections, drugs, autoimmune disease, tumours, and malignant hypertension. Transplant-related causes, such as antibody-mediated rejection, calcineurin inhibitors, and viral infections, need to be considered as well. The authors report a rare case of TMA in a kidney transplant recipient, whose investigation revealed malignant hypertension secondary to primary hyperaldosteronism.

Introduction. Recent data have emerged about a protective association between JCV viruria and chronic kidney disease (CKD). Material and Methods. Single-center retrospective cohort study; 230 living kidney donors (LKD) candidates and 59 potential living kidney receptors (LKR) were enrolled. Plasma and urinary JCV and BKV viral loads were measured in all LKD candidates and in nonanuric LKR candidates. Twenty-six living kidney transplant surgeries were performed. LKR were followed in order to evaluate BKV and JCV viremia and urinary viral shedding after KT. Results. In LKD candidates, JCV viruria was negatively associated with proteinuria of >200 mg/24 hours (JC viruric LKD: 12.5% vs JCV nonviruric LKD: 26.7%, p=0.021, OR:0.393; 95% CI: 0.181–0.854). In a multivariate analysis, LKD candidates with JCV viruria had a lower risk of proteinuria of >200 mg/24 hours (p=0.009, OR: 0.342, 95% CI: 0.153–0.764), in a model adjusted for age, gender, presence of hypertension, and eGFR <80 mL/min. Prevalence of JCV viruria was higher in LKD candidates when compared with LKR candidates (40.0% vs 1.7%, p<0.001). Among the 26 LKR, 14 (53.8%) KT patients evolved with JCV viruria; 71.4% received a graft from a JCV viruric donor. Conclusion. Our data corroborate the recent findings of an eventual protective association between JCV viruria and kidney disease, and we extrapolated this concept to a South European population.

Abstract Background and Aims Acute kidney injury (AKI) is one of the most common and severe complications in intensive care units’ (ICU) patients. It is associated with worst outcomes, such as longer hospital stays and higher mortality. In the past years three consensus have been developed to provide uniform identification of AKI in clinical practice. An ideal classification should be sensitive but also correlate with the outcomes. RIFLE and AKIN have been exhaustively studied in critical patients. In the studies made until date, KDIGO classifications seems to be as sensitive as the other two. With this study the authors intend to compare the three systems of AKI classification in an ICU population. Method Retrospective observational study with descriptive and bivariate analysis using SPSS Statistics. Demographic and laboratory studies were collected from the patient’s charts. The authors included patients who were admitted to a polyvalent ICU in the first six months of 2019. The exclusion criteria were patients under 18 years old, pregnant women, stage 5 chronic kidney disease and less than 24 hours ICU stays. Only the serum creatinine, and not urine output, was used as criteria to the three classifications. Results A total of 130 patients were studied. The mean age was 62.20±15.78 years (min 19; max 87) and 54.6% (n=71) were male. Medical causes were the most frequent type of admission (n=82; 63.1%). The median length of ICU and hospital stays were 6.50±9.19 days (min 2; max 48) and 23.00±25.68 days (min 2; max 126) respectively. The mortality rate in ICU and hospital were, respectively, 9.2% (n=12) and 20% (n=26). Eight patients (6.2%) needed renal replacement therapy. KDIGO classification identified more patients with AKI than RIFLE (p<0.001) and AKIN (p<0.001). There were no statistically differences between the median length of ICU (p=0.191 for KDIGO, p=0.257 for AKIN and p=0.223 for RIFLE) or hospital (p=0.762 for KDIGO, p=0.096 for AKIN and p=0.105 for RIFLE) stays between the patients with and without AKI by the 3 classifications. There was a significant statistically association between mortality in the ICU and AKI for KDIGO (p=0.008) and AKIN (p=0.004) classifications, but not for RIFLE (p=0.167). Likewise, there was also an association between mortality in the hospital and AKI patients identified by KDIGO (p<0.0001) and AKIN (p=0.001) classifications, but not with RIFLE (p=0.054). The AKI patients that were identified by KDIGO criteria but not by AKIN did not have and association with ICU mortality (p=0.28) but did have a statically significant association with hospital death (p=0.026) with an odds ratio of 4 (CI 95% [1.229-13.018]). Conclusion The authors concluded that KDIGO classification is the most sensitive of the three for AKI in critical patients. There were no differences in the length of ICU or hospital stays between the 3 classifications cases identified. On the other hand, there was a statistically association between KDIGO and AKIN cases with ICU and hospital mortality, but not with RIFLE. Still, patients who are identified by KDIGO but not by AKIN criteria have an odd 4 times higher to die in the hospital. This means that KDIGO classification is the most sensitive and correlates better with outcomes in critical patients with AKI than the other two.

Abstract Background and Aims Membranous nephropathy (MN) is one of the most common causes of nephrotic syndrome in adults. Some studies have suggested that glycosuria is present in the most severe cases of MN and this finding may be associated with tubular injury caused by the overload of filtered proteins. The aim of this study was to evaluate the association between glycosuria in MN and severity and prognosis of the disease. Method We conducted a 36-month retrospective cohort study with all patients diagnosed in the last 10 years in our centre with primary MN confirmed by renal biopsy. Data collection was made from patients’ charts. Patients were divided in two groups according to their glycosuric status at the diagnosis. Exclusion criteria: patients with diabetes and glucose intolerance, use of SGLT2 inhibitors, transplant kidney patients and secondary MN. Results We studied 27 patients with primary MN. Four patients (14.8%) presented glycosuria at the time of diagnosis. Glycosuric and non-glycosuric groups had comparable demographic data. We found that glycosuric patients had higher baseline albuminuria (10.7±8.6 vs 4.6±4.1 g/g, p=0.029) and lower estimated glomerular filtration rate (eGFR) (39.2±24.6 vs 75.2±30.7 ml/min/1.73m2, p=0.037). We also found that patients with glycosuria had higher interstitial fibrosis and tubular atrophy (IFTA) (33.8%±21.4 vs 10.7%±17.1, p=0.035) but no differences in the percentage of glomerular sclerosis. There were no differences between groups in serum albumin, haemoglobin or therapy. At the end of the follow-up period there was no difference in eGFR decline rate (ml/min/year), 3-year eGFR, 3-year albuminuria and 3-year chronic kidney disease stage 5D incidence. Conclusion Prevalence of glycosuria in primary MN is approximately 15%. Its presence at the time of diagnosis was associated with more severe clinical and histological markers: lower eGFR, higher albuminuria and higher IFTA. However, we did not find association between glycosuric status at diagnosis and disease progression. Prospective, bigger and longer studies are needed to evaluate these questions.

Abstract Background and Aims Multiple studies have shown that tubular damage is common in glomerular diseases and that it correlates better with chronic kidney disease (CKD) progression than glomerular lesion itself. The link between glomerular and tubular damage is not entirely established. Glycosuria can be found in (proximal) tubular dysfunction and may be used as a marker of tubular lesion and CKD progression. The aim of this study was to evaluate the association between glycosuria (at the diagnosis) and known histological prognostic markers (glomerular sclerosis (%GS) and interstitial fibrosis/tubular atrophy (IFTA)) and CKD progression, in patients with primary glomerulopathies (GP). Method We conducted a 36-month retrospective cohort study with 110 patients with primary GP confirmed by renal biopsy in the last 10 years in our centre – 39 (35.5%) IgA Nephropathy, 27 (24.5%) Membranous Nephropathy, 26 (23.6%) Focal Segmental Glomerulosclerosis and 18 (16.4%) Minimal Change Disease. Patients were divided in two groups according to their glycosuric status at the time of the diagnosis. Data was collected from patients’ charts. Exclusion criteria: patients with diabetes or glucose intolerance, use of SGLT2 inhibitors, secondary GP and transplant kidney patients. Results The global prevalence of glycosuria was 9.1% (n=10). Glycosuric patients had, at baseline, higher serum creatinine (3.9±5.1 vs 1.7±1.3mg/dL, p=0.001), higher baseline albuminuria (7.1±6.3 vs 3.2±3.4 g/g, p=0.002) and lower serum albumin (2.3±0.7 vs 3.2±1.1 g/dL, p=0.022). Both groups had similar proportion of patients that underwent immunosuppressive therapy. At the end of the follow-up, in glycosuric patients, only albuminuria was higher (3.3±0.6 vs 0.7±0.8 g/g, p<0.0001); the eGFR decline rate (ml/min/year), 3-year eGFR and 3-year CKD stage 5D incidence were not statistically different. Glomerular sclerosis (%GS) and interstitial fibrosis and tubular atrophy (IFTA) were not different between groups. These results were confirmed by multivariate analysis. Conclusion Patients with primary GP with glycosuria at diagnosis had higher baseline creatinine and albuminuria. Even though a worse clinical presentation, glycosuria was not associated with well-known prognostic factors (%GS and IFTA) or CKD progression. We can hypothesize that patients with primary GP with glycosuria have severe diseases at diagnosis, but the lesions may have greater reversibility. Prospective and longer studies are needed to confirm these results.

Osmotic demyelination syndrome (ODS) is characterized by loss of myelin in various parts of the central nervous system. It is mainly caused by a rapid correction of hyponatremia, although other factors that may cause rapid rise in serum osmolality can also be associated with its development. Its prognosis is poor and the recovery rate is unknown. The authors report a rare case of a patient with multiple risk factors for ODS, without hyponatremia, who developed ODS and surprisingly recovered. This case report highlights the importance of recognizing risk factors for the development of ODS, even if the main one is not present.

Abstract Primary hyperparathyroidism is an endocrine disorder characterized by hypercalcemia and elevated or inappropriately normal levels of parathyroid hormone. The diagnosis is based on a biochemical evaluation, and a neck ultrasound is the first choice during pregnancy to access the parathyroid glands. Manifestations during pregnancy are rare and can be present with life-threatening complications, so the diagnosis is challenging. The conservative treatment is limited, and there is not enough data about its safety and efficacy during pregnancy. Surgery is the only curative treatment, and a parathyroidectomy performed during the second or third trimesters is considered safe. Recently, some authors suggested an association between primary hyperparathyroidism and preeclampsia. We describe a case of preeclampsia with severe features at 27 weeks of gestational age. The severity of the preeclampsia motivated an early termination of the pregnancy by cesarean section. During the postpartum period, the patient presented life-threatening complications, such as severe hypercalcemia and acute pancreatitis. An ultrasound exam found two parathyroid nodules, suggestive of parathyroid adenomas. The patient recovered after the pharmacological correction of the calcemia levels.

Trabalho final de mestrado integrado em Medicina (Biologia Aplicada/Medicina Interna), apresentado a Faculdade de Medicina da Universidade de Coimbra.