Intermittent hemodiafiltration as a down-step transition therapy in patients with acute kidney injury admitted to intensive care unit who initially underwent continuous venovenous hemodiafiltration.

BACKGROUND/AIMS: Continuous renal replacement therapies (CRRT) are initially employed in patients with acute kidney injury (AKI) in ICU setting. After the period of serious illness, hemodialysis is usually used as a mode of transition from CRRT. Intermittent hemodiafiltration (HDF) is not commonly applied in this scenario. OBJECTIVES: To evaluate the feasibility of using HDF as transition therapy after CVVHDF in critically patients with AKI. METHODS: An observational and prospective pilot study was conducted in ICU patients with dialysis-requiring AKI. Patients were initially treated with CVVHDF and, after medical improvement, those who still needed renal replacement therapy were switched to HDF treatment. RESULTS: Ten Patients underwent 53 HDF sessions (mean of 5.3 sessions/patient). The main cause of renal dysfunction was sepsis (N = 7; 70%). The APACHE II mean score was 27.6 ± 6.9. During HDF treatment, the urea reduction ratio was 64.5 ± 7.5%, for ß-2 microglobulin serum levels the percentage of decrease was 42.0 ± 7.8%, and for Cystatin C was 36.2 ± 6.9%. Five episodes of arterial hypotension occurred (9.4% of sessions). There were 20 episodes of electrolytic disturbance (37.7% of sessions), mainly hypophosphatemia. No pyrogenic or suggestive episode of bacteremia was observed. CONCLUSION: Hemodiafiltration was safe and efficient to treat critically ill patients with acute kidney injury during the transition phase from continuous to intermittent dialysis modality. Special attention should be paid regarding the occurrence of electrolytic disturbance, mainly hypophosphatemia.

Acute Kidney Injury and Renal Replacement Therapy in Critically Ill COVID-19 Patients: Risk Factors and Outcomes: A Single-Center Experience in Brazil.

BACKGROUND: Critically ill patients with COVID-19 may develop multiple organ dysfunction syndrome, including acute kidney injury (AKI). We report the incidence, risk factors, associations, and outcomes of AKI and renal replacement therapy (RRT) in critically ill COVID-19 patients. METHODS: We performed a retrospective cohort study of adult patients with COVID-19 diagnosis admitted to the intensive care unit (ICU) between March 2020 and May 2020. Multivariable logistic regression analysis was applied to identify risk factors for the development of AKI and use of RRT. The primary outcome was 60-day mortality after ICU admission. RESULTS: 101 (50.2%) patients developed AKI (72% on the first day of invasive mechanical ventilation [IMV]), and thirty-four (17%) required RRT. Risk factors for AKI included higher baseline Cr (OR 2.50 [1.33-4.69], p = 0.005), diuretic use (OR 4.14 [1.27-13.49], p = 0.019), and IMV (OR 7.60 [1.37-42.05], p = 0.020). A higher C-reactive protein level was an additional risk factor for RRT (OR 2.12 [1.16-4.33], p = 0.023). Overall 60-day mortality was 14.4% {23.8% (n = 24) in the AKI group versus 5% (n = 5) in the non-AKI group (HR 2.79 [1.04-7.49], p = 0.040); and 35.3% (n = 12) in the RRT group versus 10.2% (n = 17) in the non-RRT group, respectively (HR 2.21 [1.01-4.85], p = 0.047)}. CONCLUSIONS: AKI was common among critically ill COVID-19 patients and occurred early in association with IMV. One in 6 AKI patients received RRT and 1 in 3 patients treated with RRT died in hospital. These findings provide important prognostic information for clinicians caring for these patients.

Serum Soluble-Fas, Inflammation, and Anemia in Acute Kidney Injury.

Anemia is a common feature in critically ill patients. Serum soluble-Fas (sFas) levels are associated with anemia in chronic kidney disease. It is possible that sFas levels are also associated with anemia in acute kidney injury (AKI) patients. The study aims to investigate the relationship between serum levels of sFas, erythropoietin (Epo), inflammatory cytokines, and hemoglobin (Hb) concentration in critically ill patients with AKI. We studied 72 critically ill patients with AKI (AKI group; n = 53) or without AKI (non-AKI group; n = 19), and 18 healthy volunteers. Serum sFas, Epo, tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6, IL-10, iron status, and Hb concentration were analyzed in all groups. We also investigated the correlation between these variables in the AKI group. Critically ill patients (AKI and non-AKI groups) had higher serum levels of Epo than healthy volunteers. Hb concentration was lower in the AKI group than in the other groups. Serum sFas, IL-6, TNF-α, and ferritin levels were higher in the AKI group. Hb concentration correlated negatively with serum IL-6 (r = -0.37, P = 0.008), sFas (r = -0.35, P = 0.01), and Epo (r = -0.27, P = 0.04), while serum sFas correlated positively with iron levels (r = 0.36, P = 0.008) and IL-6 (r = 0.28, P = 0.04) in the AKI group. In multivariate analysis, after adjusting for markers of inflammation and iron stores, only serum sFas levels (P = 0.03) correlated negatively with Hb concentration in the AKI group. Serum Epo and inflammatory cytokine levels are elevated in critically ill patients with or without AKI. Serum levels of sFas are elevated and independently associated with anemia in critically ill patients with AKI.

Cystatin C at Admission in the Intensive Care Unit Predicts Mortality among Elderly Patients.

Introduction. Cystatin C has been used in the critical care setting to evaluate renal function. Nevertheless, it has also been found to correlate with mortality, but it is not clear whether this association is due to acute kidney injury (AKI) or to other mechanism. Objective. To evaluate whether serum cystatin C at intensive care unit (ICU) entry predicts AKI and mortality in elderly patients. Materials and Methods. It was a prospective study of ICU elderly patients without AKI at admission. We evaluated 400 patients based on normality for serum cystatin C at ICU entry, of whom 234 (58%) were selected and 45 (19%) developed AKI. Results. We observed that higher serum levels of cystatin C did not predict AKI (1.05 ± 0.48 versus 0.94 ± 0.36 mg/L; P = 0.1). However, it was an independent predictor of mortality, H.R. = 6.16 (95% CI 1.46-26.00; P = 0.01), in contrast with AKI, which was not associated with death. In the ROC curves, cystatin C also provided a moderate and significant area (0.67; P = 0.03) compared to AKI (0.47; P = 0.6) to detect death. Conclusion. We demonstrated that higher cystatin C levels are an independent predictor of mortality in ICU elderly patients and may be used as a marker of poor prognosis.

Nec-1 protects against nonapoptotic cell death in cisplatin-induced kidney injury.

BACKGROUND/AIMS: Necrostatin-1 (Nec-1) inhibits necroptosis, a nonapoptotic cell death pathway. Acute kidney injury (AKI) is a clinical problem of high incidence and mortality. It involves several mechanisms of cell death. We aim to evaluate the effect of Nec-1 in the toxic kidney injury model by cisplatin. METHODS: We analyzed the effect of Nec-1 in AKI by cisplatin in human proximal tubule cells by flow cytometry. RESULTS: Our results show that Nec-1 has no effect on apoptosis in renal tubular epithelial cells (Nec-1 + Cis group 13.4 ± 1.7% vs. Cis group 14.6 ± 1.4%) (p > 0.05). But, in conditions in which apoptosis was blocked by benzyloxy-carbonyl-Val-Ala-Asp-fluoromethyl ketone (z-VAD-fmk) the use of Nec-1 completely reversed cell viability (Nec-1 + Cis + z-VAD group 72.9 ± 6.3% vs. Cis group 35.5 ± 2.2%) (p < 0.05) suggesting that Nec-1 has effect on nonapoptotic cell death (necroptosis). CONCLUSION: Our findings suggest that the combined use of apoptosis and necroptosis inhibitors can provide additional cytoprotection in AKI. Furthermore, this is the first study to demonstrate that Nec-1 inhibits tubular kidney cell death and restores cell viability via a nonapoptotic mechanism.

Immunological induction with thymoglobulin: reduction in the number of doses in renal transplant from deceased donor / Indução imunológica com timoglobulina: redução no número de doses em transplante de rim com doador falecido

ABSTRACT Objective: To compare three different regimens of thymoglobulin induction. Methods: One hundred seventy two patients submitted to renal transplantation from a dead donor were divided into three groups according to the total number of thymoglobulin doses used in the post-transplantation surgery: Group 1, until 14 doses - May 2002 to June 2004 (n = 48); Group 2, until 7 doses - July 2004 to December 2006 (n = 57); Group 3, until 4 doses - January 2007 to July 2009 (n = 67). The three groups were compared according to the main outcomes. Results: The main demographic differences among the groups were: greater dialysis time in Group 3 (p < 0.001 for Group 1; and p = 0.04 for Group 2); donor age, greater in Groups 2 and 3 (p = 0.02; p = 0.01, respectively); and cold ischemia time progressively greater from Group 1 to 3: 19.5 ± 5.1 to 24.6 ± 5.7 hours (p < 0.001). In relation to the inhibitor of calcineurin, the relation Tac/Csa was 14.6/66.7% in Group 1, 78.9/12.3% in Group 2 and 100/0% in Group 3. Reflecting the increase in cold ischemia time, the incidence of delayed graft function was 64.6%, 68.4% e 82.1% in Groups 1, 2 and 3, respectively (p = ns). The incidence of acute rejection was similar in the three groups: 16.7% (1); 16.3% (2) and 16.4 (3) - p = ns. The prevalence of viremia for cytomegalovirus was 61.7% in Group 1, 66.1% in Group 2 and 83.3% in Group 3 (p = ns). There were no difference related to the number of infected cells with cytomegalovirus in antigenemia, according to the groups, however, patients in Group 3 had an earlier diagnosis: from 64.3 ± 28.5 days in Grup 2, to 47.1 ± 22.5 days, in Group 3, p < 0.001. Survival of the graft in one year was 89.6%, 92.9% and 91.0%, in Groups 1, 2 and 3, respectively (p = ns). The graft function was much better with the lower doses of thymoglobulin: Group 1: 57.0 ± 20.0 mL/min; Group 2: 67.0 ± 18.4 mL/min (p = 0.008); Group 3: 71.2 ± 18.4 mL/min (p < 0.001, Group 1 versus Group 3; p = 0.06, Group 1 versus Group 2). There was a significant reduction in the costs of induction protocol from U$ 7,567.02 to U$ 3,485.56 (p < 0.001). Conclusions: The total number of thymoglobulin doses for immunologic induction could be reduced in a safe and effective way, without a negative impact in graft rejection or survival, preserving renal function and being significantly cheaper.

RESUMO Objetivo: Comparar três regimes diferentes de indução com timoglobulina. Métodos: Cento e setenta e dois pacientes submetidos a transplante de rim com doador falecido foram divididos em três grupos, de acordo com o número total de doses de timoglobulina utilizada no pós-operatório: Grupo 1, até 14 doses - Maio de 2002 a Junho de 2004 (n = 48); Grupo 2, até 7 doses - Julho de 2004 a Dezembro de 2006 (n = 57); Grupo 3, até 4 doses - Janeiro de 2007 a Julho de 2009 (n = 67). Os três grupos foram comparados de acordo com os principais desfechos. Resultados: As principais diferenças demográficas entre os três grupos foram: tempo em diálise, que foi maior no Grupo 3 (p < 0,001 para o Grupo 1; p = 0,04 para o Grupo 2); idade do doador, maior nos Grupos 2 e 3 (p = 0,02; p = 0,01, respectivamente); e o tempo de isquemia fria, progressivamente maior do Grupo 1 ao 3: 19,5 ± 5,1 para 24,6 ± 5,7 horas (p < 0,001). Em relação ao inibidor de calcineurina utilizado, a relação entre Tac/Csa foi de 14,6/66,7% no Grupo 1, 78,9/12,3% no Grupo 2 e de 100/0% no Grupo 3. Refletindo o aumento no tempo de isquemia fria, a incidência de delayed graft function foi de 64,6%, 68,4% e 82,1% nos Grupos 1, 2 e 3, respectivamente (p = ns). A incidência de rejeição aguda foi semelhante nos três grupos: 16,7% (1), 16,3% (2) e 16,4% (3) - p = ns. A prevalência de viremia para citomegalovírus foi de 61.7% no Grupo 1; 66,1% no Grupo 2; e 83,3% no Grupo 3 (p = ns). Não houve diferenças quanto ao número de células infectadas com o citomegalovírus na antigenemia, de acordo com os grupos; entretanto, os pacientes do Grupo 3 tiveram diagnostico mais precoce: de 64,3 ± 28,5 dias no Grupo 2, para 47,1 ± 22,5 dias no Grupo 3 (p < 0,001). A sobrevida do enxerto em um ano foi de 89,6%, 92,9% e 91,0%, nos Grupos 1, 2 e 3, respectivamente (p = ns). A função do enxerto foi substancialmente melhor com menor número de doses de timoglobulina: Grupo 1: 57,0 ± 20,0 mL/min; Grupo 2: 67,0 ± 18,4 mL/min (p = 0,008); Grupo 3: 71,2 ± 18,4 mL/min (p < 0,001, Grupo 1 versus Grupo 3; p = 0,06, Grupo 1 versus Grupo 2). Houve uma redução significativa no custo do protocolo de indução de U$ 7.567,02 para U$ 3.485,56 (p < 0,001). Conclusão: O número total de doses de timoglobulina para indução imunológica pôde ser reduzido de forma segura e eficaz, sem impacto negativo na incidência de rejeição ou sobrevida do enxerto, com preservação da função renal, sendo significativamente mais barato.

Immunological induction with thymoglobulin: reduction in the number of doses in renal transplant from deceased donor.

OBJECTIVE: To compare three different regimens of thymoglobulin induction. METHODS: One hundred seventy two patients submitted to renal transplantation from a dead donor were divided into three groups according to the total number of thymoglobulin doses used in the post-transplantation surgery: Group 1, until 14 doses - May 2002 to June 2004 (n = 48); Group 2, until 7 doses - July 2004 to December 2006 (n = 57); Group 3, until 4 doses - January 2007 to July 2009 (n = 67). The three groups were compared according to the main outcomes. RESULTS: The main demographic differences among the groups were: greater dialysis time in Group 3 (p < 0.001 for Group 1; and p = 0.04 for Group 2); donor age, greater in Groups 2 and 3 (p = 0.02; p = 0.01, respectively); and cold ischemia time progressively greater from Group 1 to 3: 19.5 ± 5.1 to 24.6 ± 5.7 hours (p < 0.001). In relation to the inhibitor of calcineurin, the relation Tac/Csa was 14.6/66.7% in Group 1, 78.9/12.3% in Group 2 and 100/0% in Group 3. Reflecting the increase in cold ischemia time, the incidence of delayed graft function was 64.6%, 68.4% e 82.1% in Groups 1, 2 and 3, respectively (p = ns). The incidence of acute rejection was similar in the three groups: 16.7% (1); 16.3% (2) and 16.4 (3) - p = ns. The prevalence of viremia for cytomegalovirus was 61.7% in Group 1, 66.1% in Group 2 and 83.3% in Group 3 (p = ns). There were no difference related to the number of infected cells with cytomegalovirus in antigenemia, according to the groups, however, patients in Group 3 had an earlier diagnosis: from 64.3 ± 28.5 days in Grup 2, to 47.1 ± 22.5 days, in Group 3, p < 0.001. Survival of the graft in one year was 89.6%, 92.9% and 91.0%, in Groups 1, 2 and 3, respectively (p = ns). The graft function was much better with the lower doses of thymoglobulin: Group 1: 57.0 ± 20.0 mL/min; Group 2: 67.0 ± 18.4 mL/min (p = 0.008); Group 3: 71.2 ± 18.4 mL/min (p < 0.001, Group 1 versus Group 3; p = 0.06, Group 1 versus Group 2). There was a significant reduction in the costs of induction protocol from U$ 7,567.02 to U$ 3,485.56 (p < 0.001). CONCLUSIONS: The total number of thymoglobulin doses for immunologic induction could be reduced in a safe and effective way, without a negative impact in graft rejection or survival, preserving renal function and being significantly cheaper.

Diagnosis and treatment of acute antibody-mediated rejection in renal transplant: the role of C4d and donor-specific antibody identification / Diagnóstico e tratamento da rejeição aguda mediada por anticorpo no transplante renal: papel do C4d e da pesquisa de anticorpo específico contra o doador

Objective: To evaluate the incidence of antibody-mediated rejection after the C4d and donor specific antibody detection was provided by Luminex in renal transplantation biopsies; to compare acute antibody-mediated rejection characteristics as related to acute cellular rejection; to evaluate the impact on the incidence of acute antibody mediated rejection after the utilization of cross match test by flux cytometry and the detection of pre-transplantation donor specific antibody in patients with previous history of exposition to alloantigens. Methods: One hundred twenty-four renal transplanted patients were evaluated through the detection of C4d in early biopsies of those presenting graft dysfunction and the detection of antibody against donor when C4d was positive. The acute antibody mediated rejection was treated by plasmapheresis and intravenous immunoglobulin. Results: The incidence of acute rejection was 18.8%, being the acute cellular rejection 14.9% and acute antibody mediated rejection 6.6%. When both were compared, the acute antibody-mediated rejection were earlier than the acute cellular rejection (12.5 versus 59.9 days, p = NS), being more frequent in female patients (75 versus 29%, p = 0.05), with deceased donors (75 versus 33%, p = 0.09), with higher dialysis time (87.7 versus 47.4, p = 0.03), greater number of transfusion episodes (4.6 versus 1.4, p = 0.02), greater panel reaction activity (28.0 versus 4.8, p = 0.03) and more frequently in re-transplanted patients (50 versus 5.6%, p = 0.02). Delayed graft function was more frequent in antibody mediated rejection (100 versus 50%, p = 0.02). All patients with acute cellular rejection reversed graft function after treatment, with 100% graft survival after one year. Among patients with acute antibody-mediated rejection, the treatment with plasmapheresis and immunoglobulin was efficient in reducing the titers of donor specific antibody (2605 versus 202 mfi, p < 0.001), but 3/8 of patients evolved to graft loss, making graft survival of 62.5% (p < 0.001). Conclusions: The routine use of detecting C4d and donor specific antibody increased the incidence of acute rejection. Acute antibody-mediated rejection presented clinical profile and therapeutic response different from acute cellular rejection, identifying a worse prognosis as well as therapeutic success.

Objetivo: Avaliar a incidência da rejeição mediada por anticorpo depois de instituída a pesquisa de C4d em biópsias de rim transplantado e pesquisa de anticorpo específico de doador pelo Luminex; comparar as características da rejeição aguda mediada por anticorpo em relação à rejeição aguda celular; avaliar o impacto na incidência de rejeição aguda mediada por anticorpo após utilizar a prova cruzada por citometria de fluxo e pesquisa de anticorpo específico de doador pré-transplante em pacientes com histórico de exposição prévia à aloantígenos. Métodos: Foram avaliados 124 pacientes transplantados renais, com pesquisa de C4d em biópsias precoces em pacientes com disfunção do enxerto e pesquisa de anticorpo contra o doador quando o C4d foi positivo. A rejeição aguda mediada por anticorpo foi tratada com plasmaferese e imunoglobulina intravenosa. Resultados: Foi encontrada uma incidência de rejeição aguda de 18,8%, com frequência de episódios de rejeição aguda celular de 14,9% e de rejeição aguda mediada por anticorpo de 6.6%. Quando comparados com rejeição aguda celular, os episódios de rejeição aguda mediada por anticorpo foram mais precoces (12,5 versus 59,9 dias, p = NS), sendo mais frequentes em pacientes femininas (75% versus 29%, p = 0,05), com doadores falecidos (75% versus 33%, p = 0.09), com maior tempo de diálise (87,7 versus 47,4, p = 0,03), maior número de transfusões (4,6 versus 1,4, p = 0,02), maior atividade contra painel (28,0 versus 4,8, p = 0,03) e mais frequentemente retransplantados (50 versus 5,6%, p = 0,02). Função retardada do enxerto foi mais frequente nos pacientes com rejeição aguda mediada por anticorpo (100 versus 50%, p = 0,02). Todos os pacientes com rejeição aguda celular reverteram a função do enxerto após o tratamento, com sobrevida do enxerto, em um ano, de 100%. Entre os pacientes com rejeição aguda mediada por anticorpo, o tratamento com plasmaferese e imunoglobulina foi eficiente em reduzir os títulos de anticorpo específico de doador (2.605 versus 202 mpi, p < 0,001), mas 3/8 pacientes evoluíram para perda do enxerto, conferindo sobrevida do enxerto de 62,5% (p < 0,001). Conclusões: O uso rotineiro da pesquisa de C4d e anticorpo doador específico aumentou a incidência de rejeição aguda. A rejeição aguda mediada por anticorpo apresentou perfil clínico e resposta terapêutica diferentes da rejeição aguda celular, conferindo-lhe pior prognóstico e pior resposta terapêutica.