Browsing by Author "Aires, I"
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- ABO-Incompatible Liver Transplantation in Acute Liver Failure: A Single Portuguese Center StudyPublication . Mendes, M; Ferreira, AC; Ferreira, A; Remédio, F; Aires, I; Cordeiro, A; Mascarenhas, A; Martins, A; Pereira, P; Glória, H; Perdigoto, R; Veloso, J; Ferreira, P; Oliveira, J; Silva, M; Barroso, E; Nolasco, FINTRODUCTION: ABO-incompatible liver transplantation (ABOi LT) is considered to be a rescue option in emergency transplantation. Herein, we have reported our experience with ABOi LT including long-term survival and major complications in these situations. PATIENT AND METHODS: ABOi LT was performed in cases of severe hepatic failure with imminent death. The standard immunosuppression consisted of basiliximab, corticosteroids, tacrolimus, and mycophenolate mofetil. Pretransplantation patients with anti-ABO titers above 16 underwent plasmapheresis. If the titer was above 128, intravenous immunoglobulin (IVIG) was added at the end of plasmapheresis. The therapeutic approach was based on the clinical situation, hepatic function, and titer evolution. A rapid increase in titer required five consecutive plasmapheresis sessions followed by administration of IVIG, and at the end of the fifth session, rituximab. RESULTS: From January 2009 to July 2012, 10 patients, including 4 men and 6 women of mean age 47.8 years (range, 29 to 64 years), underwent ABOi LT. At a mean follow-up of 19.6 months (range, 2 days to 39 months), 5 patients are alive including 4 with their original grafts. One patient was retransplanted at 9 months. Major complications were infections, which were responsible for 3 deaths due to multiorgan septic failure (2 during the first month); rejection episodes (4 biopsy-proven of humoral rejections in 3 patients and 1 cellular rejection) and biliary. CONCLUSION: The use of ABOi LT as a life-saving procedure is justifiable in emergencies when no other donor is available. With careful recipient selection close monitoring of hemagglutinins and specific immunosuppression we have obtained acceptable outcomes.
- Acute Allograft Kidney Dysfunction 18 Years After TransplantationPublication . Viana, H; Mesquita, I; Aires, I; Carvalho, F; Nolasco, F
- Adenovirus Infection in a Kidney–Pancreatic Transplant Recipient: Case ReportPublication . Damas, J; Vida, AC; Marques, J; Caeiro, F; Aires, I; Dias, JM; Bigotte Vieira, M; Cotovio, P; Magriço, R; Ferreira, AAdenovirus infection in transplant recipients may present from asymptomatic viremia to multisystemic involvement. Most frequently, it occurs in the first year after a kidney transplant, and it is secondary to the reactivation of latent disease. However, primary infection may occur, and disseminated disease is more common when related to primary infection. Kidney involvement may be confirmed by biopsy, although diagnosis may be presumptive. Reduction of immunosuppression and supportive care are important components of therapy. CASE DESCRIPTION: A 41-year-old female renal-pancreatic recipient 12 years before with chronic renal graft dysfunction and a functional pancreatic graft had a history of cytomegalovirus and polyoma virus infection 2 years after transplantation. She was taking tacrolimus, mycophenolate mofetil, and prednisolone. The patient was admitted after persistent uncharacteristic diarrhea 3 weeks before hospitalization without any relevant epidemiologic context. She was dehydrated, and the lab results showed worsened kidney function and leucocytosis. The viral culture revealed adenovirus. Vigorous hydration was implemented, and the mycophenolate mofetil dose was reduced. The patient was discharged, and renal function returned to previous values. DISCUSSION AND CONCLUSION: Adenovirus infection has a wide clinical presentation, and multisystemic involvement may occur in transplant recipients. Supportive care is paramount. The clinical features and viral culture confirm the diagnosis, although tissue samples and quantitative polymerase chain reaction may be required in more severe cases.
- An Atypical Presentation of Thrombotic Microangiopathy After Lung Transplant: a Case ReportPublication . Menezes, MM; Aires, I; Semedo, L; Calado, J; Ribeiro, F; Nolasco, FThrombotic microangiopathy (TMA) is a pathologic condition characterized by microangiopathic hemolytic anemia, thrombocytopenia, and organ injury due to microvascular endothelial lesions and thrombosis. It occurs in a variety of diseases and, unless recognized and treated, leads to severe morbidity and mortality. We present the case of a 48-year-old woman who underwent lung transplantation, initially under tacrolimus, mycophenolate mofetil (MMF), and prednisolone. Several complications emerged in the following months, including abdominal aortic and left renal artery thrombosis and cutaneous infections, although her renal function remained normal. Six months after transplant, her renal function began to deteriorate, which was assumed to be due to elevated tacrolimus levels and doses were adjusted. Due to leukopenia, MMF was changed to everolimus. One year after, she was admitted with fatigue, anemia, and renal dysfunction. Complementary exams revealed only iron deficiency, leukopenia, normal platelets, and elevated lactate dehydrogenase; her renal ultrasound was normal. A renal biopsy was performed and thrombotic microangiopathy was subsequently identified as the main cause of the renal dysfunction. Tacrolimus was therefore discontinued and MMF restarted with slow improvement of renal function. Only when everolimus was stopped did the patient's renal function show incremental improvement. TMA may be a serious complication after lung transplantation and the risk is higher when a combination of tacrolimus and everolimus is used. Renal biopsy findings are essential to confirm the final diagnosis of TMA, allowing for a change in immunosuppression to prevent permanent and severe renal damage.
- Benefits of Selective Vitamin D Receptor Activators in Kidney Transplanted PatientsPublication . Ferreira, A; Aires, I; Nolasco, F; Machado, D; Macário, F; Neves, PL; Costa, AG; Cabrita, AMN; Castro, R; Pereira, JBSevere chronic kidney disease may lead to disturbances, such as hyperphosphatemia, increased secretion of fibroblast growth factor -23 (FGF -23) and vitamin D deficiency. These may increase plasmatic levels of parathyroid hormone, and decrease plasmatic levels of calcium. Altogether, these may contribute to the development of secondary hyperparathyroidism, and to abnormalities in mineral metabolism. Kidney transplantation is the best option to improve longevity and quality of life in end -stage chronic kidney disease patients. Vitamin D deficiency has been associated with cardiovascular disease, which is the leading cause of death in chronic kidney disease. Therefore, diagnosing this deficiency may be pivotal for minimizing mortality in chronic kidney disease, because pharmacological treatments for this deficiency may be prescribed. Calcitriol is indicated for the treatment of vitamin D deficiency, both in chronic kidney disease and in kidney transplanted patients. However, calcitriol may increase the plasmatic levels of calcium and phosphorous, which can lead to vascular calcifications, that have been associated with cardiovascular mortality. Selective vitamin D receptor activators are indicated for the treatment of vitamin D deficiency in chronic kidney disease. These have the advantage of being associated with lower increases of plasmatic levels of calcium and phosphorous. These drugs also seem to have additional effects that may minimise patient morbidity and mortality, especially due to potentially reducing cardiovascular events. Unfortunately, there are few studies about the use of these drugs in kidney transplanted patients. Here we present a review about the physiology of vitamin D, the consequences of its deficiency in chronic kidney disease and in kidney transplanted patients, and about the diagnosis and treatment of this deficiency. Finally, we discuss the new line of research about the efficacy and safety of selective vitamin D receptor activators in kidney transplanted patients.
- Bone Densitometry Versus Bone Histomorphometry in Renal Transplanted Patients: A Cross‐Sectional StudyPublication . Ferreira, AC; Mendes, M; Silva, C; Cotovio, P; Aires, I; Navarro, D; Caeiro, F; Salvador, R; Correia, B; Cabral, G; Nolasco, F; Ferreira, ABone loss leads to increase risk of fractures in renal transplantation. The aim of this study was to analyse the relationship between bone densitometry (DXA) findings, bone histomorphometry and bone-related molecules 1-year after renal transplantation. We performed a cross-sectional study of de novo renal transplanted patients that agreed to perform a bone biopsy and a DXA examination 1 year after transplantation. All patients underwent a laboratory evaluation, bone biopsy, DXA examination and cardiac CT 1 year after transplantation. 67 patients were included, 16 had a normal examination, and 18 patients were classified as having osteoporosis by DXA. Correlations between bone mineral density and T-scores of total femur and femoral neck were the ones that best correlated with bone volume assessed by a bone biopsy. The sensitivity of DXA for osteoporosis diagnosis was 47.0%, and the specificity was 81.2%. The positive predictive value was 50.0%, and the negative predictive value (NPV) was 80.0%. DXA parameters also correlated with klotho and sclerostin serum levels. In this population, a normal examination excluded the presence of osteoporosis, helping in identifying patients that would not benefit from therapy. Overall, densitometry in total femur and femoral neck correlated well with bone volume measured by bone biopsy.
- Brain Natriuretic Peptide Levels Predict Morbidity and Mortality in Haemodialysis PatientsPublication . Matias, P; Jorge, C; Aires, I; Lage, H; Gil, C; Gomes, F; Arranhado, E; Ferreira, ABackground: Brain natriuretic peptide is a predictor of mortality in multiple cardiovascular diseases but its value in patients with chronic kidney disease is still a matter of debate. Patients and methods: We studied 48 haemodialysis patients with mean age 70.0±13.9 years,62.5% female, 43.8% diabetics, with a mean haemodialysis time of 38.1±29.3 months. To evaluate the role of brain natriuretic peptide as a prognostic factor in this population we performed a two-session evaluation of pre- and postmid-week haemodialysis plasma brain natriuretic peptide concentrations and correlated them with hospitalisation and overall and cardiovascular mortality over a two-year period. Results: There were no significant variations in pre– and post-haemodialysis plasma brain natriuretic peptide concentrations. Pre- and post-haemodialysis brain natriuretic peptide concentrations were significantly greater in patients who died from all causes(p=0.034 and p=0.001, respectively) and from cardiovascular causes (p=0.043 and p=0.001, respectively). Patients who were hospitalised in the two-year study period also presented greater pre- and posthaemodialysis brain natriuretic peptide concentrations(p=0.03 and p=0.036, respectively). Patients with mean brain natriuretic peptide concentrations ≥ 390 pg/mL showed a significantly lower survival at the end of the two-year study period. Conclusion: Brain natriuretic peptide was a good predictor of morbidity and mortality (overall and cardiovascular) in our population.
- Combined Lung-Kidney Transplantation: First Case in PortugalPublication . Silva, D; Dantas, C; Santos, AS; Silva, C; Aires, I; Remédio, F; Carrelhas, S; Pena, A; Eurico Reis, J; Calvinho, P; Semedo, L; Cardoso, J; Nolasco, F; Fragata, JA significant dysfunction of another organ is usually considered an absolute contraindication for lung transplantation, unless multiorgan transplantation is indicated and practical, as is the case of combined lung-kidney transplantation. Few cases of combined lung-kidney transplantation have been described in the literature; however, it is known that, in certain cases, it is the only way to offer an opportunity to selected patients with renal and lung dysfunction. The authors are not aware of any previously published case of a patient receiving both extracorporeal membrane oxygenation and continuous venovenous hemodiafiltration as a bridge for combined kidney-lung transplantation. The authors present the first case of combined lung-kidney transplantation performed in Portugal.
- Disruption of Urate Transport in Familial Renal Glucosuria and Report on SGLT2 Expression in Normal and Pathological KidneyPublication . Aires, I; Santos, AR; Bogarin, R; Genc, G; Pratas, J; Ozkaya, O; Carvalho, F; Rueff, J; Nolasco, F; Calado, JFamilial renal glucosuria (FRG) is a rare co -dominantly inherited benign phenotype characterized by the presence of glucose in the urine. It is caused by mutations in the SLC5A2 gene that encodes SGLT2, a Na+ -glucose co -transporter. The purpose of our current work was twofold: to characterize the molecular and phenotype findings of an FRG cohort and, in addition, to detail the SGLT2 expression in the adult human kidney. The phenotype of FRG pedigrees was evaluated using direct sequencing for the identification of sequence variations in the SLC5A2 gene. The expression of SGLT2 in the adult human kidney was studied by immunofluorescence on kidney biopsy specimens. In the absence of renal biopsies from FRG individuals, and in order to evaluate the potential disruption of SGLT2 expression in a glucosuric nephropathy, we have selected cases of nucleoside analogues induced proximal tubular toxicity. We identified six novel SLC5A2 mutations in six FRG pedigrees and described the occurrence of hyperuricosuria associated with hypouricaemia in the two probands with the most severe phenotypes. Histopathological studies proved that SGLT2 is localized to the brush -border of the proximal tubular epithelia cell and that this normal pattern was found to be disrupted in cases of nucleoside analogues induced tubulopathy. We present six novel SLC5A2 mutations, further contributing to the allelic heterogeneity in FRG, and identified hyperuricosuria and hypouricaemia as part of the FRG phenotype. SGLT2 is localized to the brush -border of the proximal tubule in the adult human normal kidney, and aberrant expression of the co -transporter may underlie the glucosuria seen with the use of nucleoside analogues.
- Early Renal Protocol Biopsies: For Some But Not For All Renal Transplant Patients?Publication . Navarro, D; Ferreira, AC; Caeiro, F; Nolasco, F; Cotovio, P; Aires, I; Silva, C; Remédio, F; Ferreira, A; Viana, H; Carvalho, FSubclinical rejection following renal transplant is associated with worse outcomes, which can be prevented if recognized early. Protocol allograft biopsies have emerged as an option to identify and allow treatment of subclinical rejection, but optimal timing for their performance is not established. We retrospectively evaluated a cohort of 52 low immunological risk patients, who were submitted, from 2007 to 2010, to de novo renal transplant. We separated them into two groups depending on performing an early graft protocol biopsy before hospital discharge: Group A – 32 patients (61.5%) performed a protocol biopsy, and group B – 20 patients (38.5%) did not, the biopsy being considered not essential for various reasons. We analysed patients’ demographics, biopsy complications, graft function, rejection episodes, and patient and graft survival for a median follow-up time of 63.3 months (50.3-83.7). Group A and group B differed in gender (more female patients were biopsied), dialysis vintage (higher in group A), human leucocyte antigen mismatch (higher in group A), and induction protocol (more patients submitted to thymoglobulin than to basiliximab in group A). Protocol biopsy detected histological changes in four patients (12.5%) in group A (2 cellular and 2 borderline rejections), and all were treated accordingly. Moderate peri-graft hematoma was reported in two cases (3.9%). Despite the increased risk in group A, renal function at discharge was better than in group B (p < 0.05 for serum creatinine and eGFR). During follow-up, rejection episodes were similar in the two groups. By the end of follow-up (median 63.3 months), proteinuria and renal function were similar between the two groups. Using a multivariate regression model, and despite the initial differences, at the end of follow-up, patients submitted to early protocol biopsies had similar excellent prognosis as the very low-risk patients who were not biopsied. (p = 0.5). Following our results, we propose that timing of early protocol biopsy should be individualized according to the patient’s clinical and immunological risk.