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Introduction Anticoagulant-related nephropathy (ARN) is a relatively novel recognized entity characterized by hematuria-associated acute kidney injury (AKI) in the context of overanticoagulation. Preexisting or underlying kidney disease seems to be a predisposing factor; however, few studies have described histologic findings in patients with ARN. We aimed to evaluate underlying kidney pathology in patients on oral anticoagulation who presented an episode of AKI with hematuria in whom a kidney biopsy was performed. Methods Retrospective observational multicenter case study in patients treated with oral anticoagulants who developed macroscopic or intense hematuria followed by AKI. Only patients with available kidney biopsy specimens were included. Histologic findings and clinical data throughout follow-up were analyzed. Results A total of 26 patients were included with a median age of 75 years (62–80) and a follow-up period of 10.1 months. Of the patients, 80% were male, and most cases (92%) were on anticoagulation with vitamin K antagonists (VKAs). At admission, median serum creatinine (SCr) level was 4.2 mg/dl (2.8–8.2), median international normalized ratio (INR) 2.4 (1.5–3.4), and 11 patients (42%) required acute dialysis during hospitalization. Kidney biopsy results revealed that all patients except 1 had an underlying nephropathy: IgA nephropathy (IgAN) in 19, probable IgAN in 1, diabetic nephropathy in 3, nephrosclerosis in 1, and idiopathic nodular glomerulosclerosis in 1. At 12 weeks after discharge, only 6 subjects (24%) attained complete kidney recovery whereas 7 (28%) remained on chronic dialysis. Conclusion IgAN was the most common underlying kidney disease in our biopsy-proven series of ARN, in which a significant percentage of patients did not achieve kidney function recovery.

The uptake of the current concept of chronic kidney disease (CKD) by the public, physicians and health authorities is low. Physicians still mix up CKD with chronic kidney insufficiency or failure. In a recent manuscript, only 23% of participants in a cohort of persons with CKD had been diagnosed by their physicians as having CKD while 29% has a diagnosis of cancer and 82% had a diagnosis of hypertension. For the wider public and health authorities, CKD evokes kidney replacement therapy (KRT). In Spain, the prevalence of KRT is 0.13%. A prevalent view is that for those in whom kidneys fail, the problem is ``solved'' by dialysis or kidney transplantation. However, the main burden of CKD is accelerated aging and all-cause and cardiovascular premature death. CKD is the most prevalent risk factor for lethal COVID-19 and the factor that most increases the risk of death in COVID-19, after old age. Moreover, men and women undergoing KRT still have an annual mortality which is 10-100-fold higher than similar age peers, and life expectancy is shortened by around 40 years for young persons on dialysis and by 15 years for young persons with a functioning kidney graft. CKD is expected to become the fifth global cause of death by 2040 and the second cause of death in Spain before the end of the century, a time when 1 in 4 Spaniards will have CKD. However, by 2022, CKD will become the only top-15 global predicted cause of death that is not supported by a dedicated well-funded CIBER network research structure in Spain. Leading Spanish kidney researchers grouped in the kidney collaborative research network REDINREN have now applied for the RICORS call of collaborative research in Spain with the support of the Spanish Society of Nephrology, ALCER and ONT: RICORS2040 aims to prevent the dire predictions for the global 2040 burden of CKD from becoming true. However, only the highest level of research funding through the CIBER will allow to adequately address the issue before it is too late. (C) 2021 Sociedad Espanola de Nefrologia. Published by Elsevier Espana, S.L.U.

Background. Acute interstitial nephritis (AIN) is an emerging cause of acute kidney disease. While this disease usually follows an acute course, it may occasionally recur, representing a major challenge for the clinician. Methods. We performed a retrospective, observational cohort study in 13 nephrology departments belonging to the Spanish Group for the Study of Glomerular Diseases. Patients with biopsy-proven AIN between 1996 and 2018 were included. Results. The study group consisted of 205 patients with AIN, 22 of which developed recurrent AIN (RAIN) after a median of 111 days from diagnosis. RAIN was due to a surreptitious reintroduction of a previously known implicated drug or toxic in six patients (27%), sarcoidosis in two (9%), Sjogren's syndrome in three (14%), light-chain-mediated AIN in two (9%) and tubulointerstitial nephritis and uveitis syndrome in two (9%), while in the rest of cases (32%), no precise cause could be identified. Microscopic haematuria was more frequent in patients with underlying systemic diseases. The first RAIN episode was treated with a repeated course of corticosteroids in 21 patients (95%). In six cases (27%), azathioprine and mycophenolate mofetil were added as corticosteroid-sparing agents. During a median follow-up of 30 months, 50 patients (27%) with no recurrences and 12 patients (55%) with RAIN reached Stages 4 and 5 chronic kidney disease (CKD). By multivariable logistic regression analysis, RAIN was independently associated with the risk of reaching Stages 4 and 5 CKD, even after adjusting for potential covariables. Conclusions. RAIN is infrequent but is associated with poor kidney survival. RAIN should prompt clinicians to search for an underlying aetiology other than drug induced. However, in a large percentage of cases, no precise cause can be identified.

BACKGROUND: The magnitude and kinetics of severe acute respiratory syndrome coronavirus 2-specific cell-mediated immunity (SARS-CoV-2-CMI) in kidney transplant (KT) recipients remain largely unknown. METHODS: We enumerated SARS-CoV-2-specific interferon-gamma-producing CD69+ CD4+ and CD8+ T cells at months 4 and 6 from the diagnosis of coronavirus disease 2019 (COVID-19) in 21 KT recipients by intracellular cytokine staining. Overlapping peptides encompassing the SARS-CoV-2 spike (S) glycoprotein N-terminal 1- to 643-amino acid sequence and the membrane protein were used as stimulus. SARS-CoV-2 IgG antibodies targeting the S1 protein were assessed by ELISA at month 6. RESULTS: Detectable (=0.1%) SARS-CoV-2-specific CD4+ T-cell response was found in 57.1% and 47.4% of patients at months 4 and 6. Corresponding rates for CD8+ T cells were 19.0% and 42.1%, respectively. Absolute SARS-CoV-2-specific T-cell counts increased from month 4 to month 6 in CD8+ (P=0.086) but not CD4+ subsets (P=0.349). Four of 10 patients with any detectable response at month 4 had lost SARS-CoV-2-CMI by month 6, whereas 5 of 9 patients mounted SARS-CoV-2-CMI within this period. All but 2 patients (89.5%) tested positive for SARS-CoV-2 IgG. Patients lacking detectable SARS-CoV-2-specific CD4+ response by month 6 were more likely to be under tacrolimus (100.0% versus 66.7%; P=0.087) and to have received tocilizumab for the previous COVID-19 episode (40.0% versus 0.0%; P=0.087). CONCLUSIONS: Although still exploratory and limited by small sample size, the present study suggests that a substantial proportion of KT recipients exhibited detectable SARS-CoV-2-CMI after 6 months from COVID-19 diagnosis.

The upcoming migration of satellite services to higher bands, namely the Ka- and Q-bands offers many advantages in terms of bandwidth, data rates and system capacity. However, it poses challenges as propagation effects introduced by the various atmospheric phenomena are particularly pronounced in these bands and can become a serious constraint in terms of system reliability and performance. This paper outlines the goals, organization and some first results of an ongoing large propagation campaign consortium formed across Europe under the supervision of the European Space Agency; the campaign, shall ultimately assist in the validation and development of channel models targeting these-bands. Finally, the consideration of diverse climatic conditions and elevation angles along with the evaluation of the frequency and spatio-temporal effects, shall support the development of Fading and Mitigation Techniques and their assessment using real data.

The Boqueirão pegmatite is located in the Borborema Pegmatite Province in the state of Rio Grande do Norte (NE Brazil) hosted by Neoproterozoic taconglomerates of Equador Formation. The pegma tite occurs as a concentric body displaying characteristic units according their mineralogy. The border and wall zones are composed by quartz, microcline and muscovite often displaying skeletal and graphic textures with accessory tourmaline and garnet. The intermediate zone is divided in two distinct subzones and shows a complex mineralogy exhibiting a varied phosphate association, beryl, columbite -tantalite and zircon. The innermost zone is mainly constituted by a quartz core. In addition, typical replacement bodies of albite are recognized at the eastern part of the body. Lithiophilite triphylite represents the most abundant phosphate phase exhibiting exsolutions of sarcopside and replaced by sicklerite due to Lileaching alteration, best known as Quensel Mason sequence .The scarcity of heterosite -purpurite series is remarkable. Montebrasite and triplite are also primary phosphates observed. Subsequently ,the presence of alluaudite and varulite occurrences suggests that Na-metasomatism affected the pegmatite. The whole ensemble is crosscut by an extensive alteration that resulted in secondary phosphate minerals . Electron microprobe data of triphylite-lithiophilite shows Mn/(Mn+Fe)ratios between 0.21-0.24 but also up to 0.72 which seems to indicates that the earlier pegmatite magma could be slightly fractionated; consequently,ferrisicklerite shows Mn/(Mn+Fe) values between 0.69 -0.77 in agreement with high evolution degree and suggesting that pseudomorphism may be produced by high rock/fluid ratios. Alluaudite and varulite also record Mn and Fe contents up to 0.71 similar to precursor phosphates. Furthermor eight different secondary phosphates have been identified as replacement of primary phases either as pseudomorphs or crosscutting them. They form euhedral crystals of fine grain size, spherulites or extensive masses displaying vivid colours which are ea sily identifiable. Manrich secondary phases are hureaulite, eosphorite, whiteite, jahnsite and serrabrancaite while lipscombite, phosphosiderite and mitridatite correspond to Ferich secondary association. Supergenic late origin and entrance of Ca-K,Mgrich fluids from host rock may be invoked in order to explain their formation. They do not show any relationship with processes of pegmatite crystallization. Hf content of zircon from the intermediate zone has been analysed by electron microprobe as a pow erful indicator of pegmatite evolution degree together with Mn content of phosphates. Hf content obtained is low up to 5% wt. of HfO which which points out to low fractionated pegmatite magma. Besides, the presence of ferromagnesian silicates forming the pegmat ite units such as Ferich tourmaline, garnet and green beryl is in agreement of that hypothesis. Therefore, Boqueirão corresponds to rare element pegmatite of beryl columbite phosphate subtype.

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