IgA-Dominant Infection-Associated Glomerulonephritis Following SARS-CoV-2 Infection

The renal involvement of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been reported. The etiology of kidney injury appears to be tubular, mainly due to the expression of angiotensin-converting enzyme 2, the key joint receptor for SARS-CoV-2; however, cases with glomerular implication have also been documented. The multifactorial origin of this renal involvement could include virus-mediated injury, cytokine storm, angiotensin II pathway activation, complement dysregulation, hyper-coagulation, and microangiopathy. We present the renal histological findings from a patient who developed acute kidney injury and de novo nephrotic syndrome, highly suggestive of acute IgA-dominant infection-associated glomerulonephritis (IgA-DIAGN) after SARS-CoV-2 infection, as evidenced by the presence of this virus detected in the renal tissue of the patient via immunohistochemistry assay. In summary, we document the first case of IgA-DIAGN associated to SARS-CoV-2. Thus, SARS-CoV-2 S may act as a super antigen driving the development of multisystem inflammatory syndrome as well as cytokine storm in patients affected by COVID-19, reaching the glomerulus and leading to the development of this novel IgA-DIAGN.

Refractory congestive heart failure: when the solution is outside the heart

Refractory congestive heart failure is associated with an ominous prognosis in which the treatments strategies remain scarce and not well validated. In the last years, continuous ambulatory peritoneal dialysis (CAPD) has emerged as a therapeutic alternative in this subset of patients. So far, it has been associated with a significant improvement in functional capacity and quality of life, together with a striking reduction in the risk of readmissions. We present the case of an elderly patient with severe left ventricular dysfunction and severe mitral and tricuspid regurgitation who presents recurrent admissions for anasarca. After its inclusion in a CAPD programme, the patient experienced a marked clinical and biochemical improvement despite the persistence of cardiac abnormalities. CAPD onset translates into greater sodium removal. We want to emphasize the usefulness of this therapy in the management of volume excess in patients with refractory heart failure and renal failure promoting a greater sodium removal compared with traditional diuretic strategies.

Urinary KIM-1, NGAL and L-FABP for the diagnosis of AKI in patients with acute coronary syndrome or heart failure undergoing coronary angiography

Acute kidney injury (AKI) is a common complication after coronary angiography. Early biomarkers of this disease are needed since increase in serum creatinine levels is a late marker. To assess the usefulness of urinary kidney injury molecule-1 (uKIM-1), neutrophil gelatinase-associated lipocalin (uNGAL) and liver-type fatty acid-binding protein (uL-FABP) for early detection of AKI in these patients, comparing their performance with another group of cardiac surgery patients. Biomarkers were measured in 193 patients, 12 h after intervention. In the ROC analysis, AUC for KIM-1, NGAL and L-FABP was 0.713, 0.958 and 0.642, respectively, in the coronary angiography group, and 0.716, 0.916 and 0.743 in the cardiac surgery group. Urinary KIM-1 12 h after intervention is predictive of AKI in adult patients undergoing coronary angiography, but NGAL shows higher sensitivity and specificity. L-FABP provides inferior discrimination for AKI than KIM-1 or NGAL in contrast to its performance after cardiac surgery. This is the first study showing the predictive capacity of KIM-1 for AKI after coronary angiography. Further studies are still needed to answer relevant questions about the clinical utility of biomarkers for AKI in different clinical settings.

Ischemia-reperfusion impairs blood-brain barrier function and alters tight junction protein expression in the ovine fetus

The blood-brain barrier is a restrictive interface between the brain parenchyma and the intravascular compartment. Tight junctions contribute to the integrity of the blood-brain barrier. Hypoxic-ischemic damage to the blood-brain barrier could be an important component of fetal brain injury. We hypothesized that increases in blood-brain barrier permeability after ischemia depend upon the duration of reperfusion and that decreases in tight junction proteins are associated with the ischemia-related impairment in blood-brain barrier function in the fetus. Blood-brain barrier function was quantified with the blood-to-brain transfer constant (K(i)) and tight junction proteins by Western immunoblot in fetal sheep at 127 days of gestation without ischemia, and 4, 24, or 48 h after ischemia. The largest increase in K(i) (P<0.05) was 4 h after ischemia. Occludin and claudin-5 expressions decreased at 4 h, but returned toward control levels 24 and 48 h after ischemia. Zonula occludens-1 and -2 decreased after ischemia. Inverse correlations between K(i) and tight junction proteins suggest that the decreases in tight junction proteins contribute to impaired blood-brain barrier function after ischemia. We conclude that impaired blood-brain barrier function is an important component of hypoxic-ischemic brain injury in the fetus, and that increases in quantitatively measured barrier permeability (K(i)) change as a function of the duration of reperfusion after ischemia. The largest increase in permeability occurs 4 h after ischemia and blood-brain barrier function improves early after injury because the blood-brain barrier is less permeable 24 and 48 than 4 h after ischemia. Changes in the tight junction molecular composition are associated with increases in blood-brain barrier permeability after ischemia.

[Evolution of kidney function and progression factors in nephrectomised patients]

Data recorded from external visit in hospitals, reflects high number of nephrectomized patients. Most of these patients were remitted after any surgery or deteriorizated renal function or any other associated pathology. Several studies of nephrectomized patients are reported in literature concerning both healthy patients and comorbidity factors, and renal function and its evolution are evaluated. However, obtained results present a wide variability, which needs to be assessed. In this study we present a retrospective observational study of 92 one-kidney surgical patients, visited in Nephrology surgery of University Clinic Hospital. Patients presented an average age of 67 years old (range 22-89 years old), and a post-surgery monitoring of 21 years. Population was divided in two groups according with their glomerular filtration (FG). Before surgery, group 1 presented FG < 60 ml/min and group 2 > 60 ml/min, respectively. Group 1 patients (a total of 24 patients) presented an FG average of 48 ml/min, 8% had proteinuria and 63% presented high blood pressure. 21% of them needed an average of 20 years (10-30 years) to reach E4 and E5 steps and in general, most of them progressed to insufficient renal chronic disease. Five cases achieved renal therapy replacement. Group 2 patients, composed of a total of 68 patients, had an FG average of 76.5 ml/min, and 10% of patients presented proteinuria and 34% HTA; however, 80% of group 2 patients achieve E3 step with average age of 17 years, and a post-surgery of 47 years (1-48 years). A total of 19.1 % presented an FG higher 60 ml/min with an average development of 22 years along their evolution. According to the results obtained it is suggested that monorrenal surgical patients present a low progression of renal disease and it is also observed a progressive tendency to the chronic renal failure due to emerging of proteinuria.

Colonization and diversification: towards a phylogeographic synthesis for the Canary Islands

Recently, the Canary Islands have become a focus for studies of the colonization and the diversification of different organisms. Some authors have considered Canarian endemisms as relicts of Tertiary origin, but new molecular data suggest a general pattern of continental dispersion followed by in situ speciation. Recent phylogeographic studies are revealing variants of the simple stepping-stone colonization model that seems to hold for many Hawaiian groups. Many factors can generate deviations from such a pattern: the stochastic nature of colonization, competitive exclusion, phylogenetic constraints on adaptive evolution and extinction. An understanding of island colonization and diversification can best be developed from an ecosystem level synthesis as more data for the Canarian archipelago come to hand.

[Static and dynamic responses of mechanoreceptors within gastric wall to intragastric pressure changes]

Adult cats were used under sodium pentobarbital anesthesia in order to investigate static and dynamic responses of mechanoreceptors within gastric wall to intragastric pressure changes caused by air inflation of the stomach. By means of tungsten microelectrodes, 17 afferent activities in response to gastric inflation were recorded from cervical vagal nerve trunk. Two modes of gastric inflation were applied (a) intermittent type for studying static response and (b) staircase one for studying dynamic response. The following results were obtained: Static response: An exponential relation was observed between intragastric pressure and frequency of gastric afferent activity, so maximal estimated frequency (fmax) and pressure constant could be calculated using method of extrapolation and method of least squares. Pressure constant is defined as an intragastric pressure at which frequency response is about 63% of fmax. Only one peak was seen in histogram of pressure constants of 17 afferent activities. Their average mean was 24 +/- 3 cmH2O. Dynamic response: A linear relation was observed between dynamic index and rate of pressure change. Dynamic index is defined as the net increment of frequency on dynamic phase of gastric inflation obtained by the difference between the maximal frequency and the frequency at three seconds after dynamic inflation. Dynamic constant which is considered to indicate the sensitivity of the receptor is defined by the slope of the regression line of dynamic index and rate of pressure change. Histogram of dynamic constant revealed two peaks, the large one with a mean of 10.2 +/- 4.0 imp divided by s/cmH2O divided by s and the small one with a mean of 2.5 +/- 0.5 imp divided by s/cmH2O divided by s.