MO926RAPID VS. LATE RE-TRANSPLANTATION FOR EARLY KIDNEY GRAFT LOSS

Background and Aims

Early graft failure (EGL) is a devastating complication of kidney transplantation. Patients with EGL have an increased risk of mortality of up to twelve times compared to patients who received grafts that survive beyond 30 days. Moreover, they may have become sensitized to antigens from the failed graft and that human leukocyte antigen antibodies (anti-HLA), identified on single antigen bead assays, may not be reliable until several weeks after transplantation. Thus, if rapid re-transplantation occurs, there is no certainty regarding the recipient's immunological status. Hence, there could be an increased immunological risk with the consequent disturbance of the new graft's survival.

Method

We performed a retrospective single-center observational study in re-transplanted patients with EGL (defined as graft loss before 30 days from transplant) between January 1977 and November 2019 from our center to analyze the outcomes of rapid re-transplantation (occurred within 30 days of EGL) vs late re-transplantation (occurred beyond those 30 days).

Results: T

here were 82 re-transplants after EGL. The median overall patient survival after re-transplantation was 32 years. Eight patients died within the first year. Among the mortality causes, there were four septic shocks, one cardiogenic shock, one massive pulmonary thromboembolism, one myocardial infarction, and one unknown cause. When analyzed for periods, death censored graft survival was 89% at one and five years after re-transplantation. One graft was lost at eight days due to antibody-mediated rejection (AMR), while there was one death with a functioning graft three months after re-transplantation secondary to a pulmonary embolism. Seventy-three late re-transplants occurred. When analyzed for periods, death censored graft survival was 81% and 69% at one and five years after re-transplantation, respectively. The median patient survival after late re-transplantation was 32 years. There were fewer deaths after rapid re-transplantation than late re-transplantation, but given the small number of cases in the former, this difference did not reach statistical significance (p = 0.3). There was no association between the timing of re-transplantation and an increased risk of graft failure (HR 0.30 [0.04 – 2.2]). While four rapid re-transplants did not share any incompatibilities between donors, four did share at least one HLA type I incompatibility, and one shared an incompatibility of HLA class I and class II. There were no T-cell mediated rejections (TCMR), and there was only one AMR in the rapid rapid re-transplantation group, whereas there were six TCMRs and fifteen AMRs in the late re-transplantation group (p = 0.03 and p = 0.4, respectively).

Conclusion

Rapid re-transplantation appears to be safe and does not entail increased rejection risk, nor it diminishes long-term graft survival when compared to late re-transplantation.

MO393ACUTE RENAL REPLACEMENT THERAPY IN CRITICAL ILL OCTOGENARIAN OR OLDER PATIENTS: PROGNOSTIC FACTORS AND RENAL OUTCOMES

Background and Aims

a growing number of octogenarians or older patients are being admitted to the intensive care unit (ICU). The aim of this study was to assess factors associated with acute renal replacement therapy (ARRT) requirement in these patients and the impact of ARRT on the 90-day ICU mortality. Also we aimed to identify prognostic factors associated with mortality risk in the group of patients that required ARRT.

Method

retrospective study of octogenarian or older patients admitted to the ICUs of Hospital Clínic de Barcelona from June 2007 to April 2019. Patients on chronic dialysis treatment or kidney transplant, and patients with limitation of therapeutic support or admitted for less than 48 hours were excluded.

Results

217 patients were included in the study, of which 36.4% required ARRT. Use of vasoactive drugs and Sequential Organ Failure Assessment (SOFA) score on admission were higher in ARRT patients (p=0.009 and <0.001). Basal estimated glomerular filtration rate (eGFR) was lower in the ARRT cohort (p<0.001). Hospital and ICU length of stay were longer in the ARRT cohort (p<0.001). Ninety-day mortality was 58.2% in the ARRT cohort and 55.8% in the control cohort, without statistical differences. In the survival analysis, only female sex and non-renal SOFA ≥6.5 were significantly associated with mortality (p= 0.005 and 0.002 respectively) in the ARRT cohort.

Conclusion

mortality was not significatively increased in the octogenarian population that required and got ARRT respect to those who did not require it. Scores like SOFA can help in the process of decision making about initiation of ARRT.

Evaluation and comparison of polysulfone TS-UL and PMMA NF-U dialyzers versus expanded hemodialysis and postdilution hemodiafiltration

Toray has created a new generation of dialyzers, the polysulphone (TS) UL series, and polymethylmethacrylate (PMMA) NF-U series, which offer enhanced efficacy over the previous TS-S series and NF-H series. The aim of this study was to evaluate the safety and efficacy of these dialyzer series versus contrasted expanded hemodialysis (HDx) and postdilution hemodiafiltration (HDF). We conducted a prospective study in 12 patients. Each patient underwent six dialysis sessions: FX80 Cordiax in HD, Toraysulfone TS-1.8 UL in HD, Theranova 400 in HDx, polymethylmethacrylate (PMMA) NF-2.1 U in HDF, Toraysulfone TS-2.1 UL in HDF, and FX80 Cordiax in HDF. The removal ratios (RRs) of urea, creatinine, ß₂ -microglobulin, myoglobin, prolactin, α₁ -microglobulin, α₁ -acid glycoprotein, and albumin were compared intraindividually. Dialysate albumin loss was also measured. The RRs for β₂ -microglobulin, myoglobin, prolactin, α₁ -microglobulin, and α₁ -acid glycoprotein were higher with the TS-2.1 UL and FX80 Cordiax dialyzers in HDF than those obtained with HD treatments and NF-2.1 U in HDF. The β₂ -microglobulin, myoglobin, and prolactin RRs were also higher with HDx than those obtained with HD treatments. The myoglobin and prolactin RRs were higher with TS-1.8 UL in HD than those obtained with helixone dialyzers in HD. Dialysate albumin loss was less than 3 g in all situations except in TS-2.1 UL in HDF. The highest global removal score values were obtained with the TS-2.1 UL and helixone dialyzers in HDF. Significant differences were found between all study situations. In conclusion, the new generation dialyzers, Toraysulfone TS Series UL and PMMA NF-U series, show excellent behaviour and tolerance in HD and HDF, representing an upgrade versus their predecessor series. The higher permeability of the TS UL series has been proven with higher efficiency in HD and maximum performance in HDF. The new PMMA NF-U series allows the use of HDF with good efficiency and complete safety.

Efficacy and safety of the Clearum dialyzer

The Clearum dialyzer, built by Medtronic, became commercially available in several European countries in 2020, but there are still no reports of in vivo data. The aim of this study was to evaluate the efficacy and risk of hypoalbuminemia of this dialyzer compared with previously evaluated hemodialysis (HD), expanded hemodialysis (HDx), and postdilution hemodiafiltration (HDF) treatments. A prospective study was carried out in 15 patients. Each patient underwent seven dialysis sessions: FX80 Cordiax in HD, Clearum HS17 in HD, Phylther 17-SD in HDx, Theranova 400 in HDx, Phylther 17-G in postdilution HDF, Clearum HS17 in postdilution HDF, and FX80 Cordiax in postdilution HDF. The reduction ratios of urea, creatinine, ß₂ -microglobulin, myoglobin, prolactin, α₁ -microglobulin, α₁ -acid glycoprotein, and albumin were compared intraindividually. Dialysate albumin loss was also measured. Comparison of dialysis techniques revealed no differences between small molecules, but HDx and HDF were significantly higher than HD with medium and large molecular weights. The Clearum dialyzer in HDF obtained similar results to FX80 Cordiax in HDF, was slightly superior to Phylther 17-G in HDF, and was statistically superior to both dialyzers in HDx. Albumin losses with the Clearum dialyzer were among the lowest, both in HD and HDF treatments. The highest global removal score (GRS) values were obtained with the helixone and Clearum dialyzers in HDF, with similar results both in HD and HDF. In addition, the GRS values with HDx treatments were statistically significantly higher than those with HD. The new Clearum dialyzer has excellent behavior and tolerance in HD and HDF. Its adequate permeability has been proven with its maximal performance in HDF, which could represent an upgrade versus its predecessor polyphenylene dialyzers.

P0485ASSOCIATION BETWEEN ANTI-GBM TITERS AND KIDNEY INFLAMMATION MEASURED BY A NEW ACTIVITY SCORE

Background and Aims

Anti-glomerular basement membrane (anti-GBM) disease is an aggressive and rare glomerulopathy characterized by rapidly progressive loss of kidney function, leading to end stage kidney disease (ESKD) in a significant amount of cases. The main objective of our study was to determine whether anti-GBM titer correlated with the rate of activity in renal biopsy and long-term kidney survival in patients with anti-GBM, hence identifying patients who would potentially benefit from more intensive treatments.

Method

A retrospective analysis was performed on the cases of anti-GBM from our center that had both a positive biopsy and serology, from 2007 to 2019. Epidemiological data, anti-GBM levels on admission, kidney function at admission, discharge and follow-up, treatment and kidney biopsy findings were collected. All biopsies were reevaluated by a single, blinded pathologist and nephrologist. Based on a recent study by van Daalen et al, a chronicity and activity histopathological score was developed. The score was divided in glomerular and interstitial sections. In the glomerular section, a sclerotic pattern (>50% of glomeruli) was given 0 points in activity and 3 in chronicity, a mixed pattern was given 1 point in activity and chronicity, and a crescentic pattern (>50% with cellular crescents) was given 3 points in activity and 0 in chronicity. In the interstitial section, the presence of fibrosis and atrophy was given between 0 and 3 points in chronicity and the presence of tubulitis or interstitial infiltrate were given points in activity (0 to 1 and 0 to 3 respectively). The presence of neutrophils in the infiltrate was given one extra point in activity. Spearman correlation was performed between anti-GBM levels and our biopsy score.

Results

Twelve cases were identified, with a median Anti-GBM titer at admission of 292 U/mL (IQR 40-1517). Ten patients were treated with cyclophosphamide, 1 with rituximab plus cyclophosphamide and 1 with only rituximab. All patients received treatment with metilprednisona and plasma exchange with a median number of sessions of 8 (range: 6-12). Only one patient was not in ESKD during follow-up (35 months), so correlation with long-term kidney survival could not be performed. On the other hand, high antibody titers correlated with more activity on biopsy (correlation coefficient 0.592, p= 0.042) and less chronicity (correlation coefficient -0.657, p= 0.02).

Conclusion

These results suggest that patients who present with higher titers have more acute inflammation and less chronicity in renal parenchima, and therefore could benefit from more intensive treatment that changes the natural history of this aggressive disease. It would be interesting to study this score in larger and multicentric cohorts in order to produce more definitive conclusions.

Optimization of dialysate bicarbonate in patients treated with online haemodiafiltration

Background

Metabolic acidosis is a common problem in haemodialysis patients, but acidosis overcorrection has been associated with higher mortality. There is no clear definition of the optimal serum bicarbonate target or dialysate bicarbonate. This study analysed the impact of reducing dialysate bicarbonate from 35 to 32 mEq/L on plasma bicarbonate levels in a cohort of patients treated with online haemodiafiltration (OL-HDF).

Methods

We performed a prospective cohort study with patients in a stable chronic OL-HDF programme for at least 12 months in the Hospital Clinic of Barcelona. We analysed pre- and post-dialysis total carbon dioxide(TCO₂₎ before and after dialysate bicarbonate reduction from 35 to 32 mEq/L, as well as the number of patients with a pre- and post-dialysis TCO₂ within 19–25 and ≤29 mEq/L, respectively, after the bicarbonate modification. Changes in serum sodium, potassium, calcium, phosphorous and parathyroid hormone (PTH) were also assessed.

Results

We included 84 patients with a 6-month follow-up. At 6 months, pre- and post-dialysis TCO₂ significantly decreased (26.78 ± 1.26 at baseline to 23.69 ± 1.92 mEq/L and 31.91 ± 0.91 to 27.58 ± 1.36 mEq/L, respectively). The number of patients with a pre-dialysis TCO₂ >25 mEq/L was significantly reduced from 80 (90.5%) to 17 (20.2%) and for post-dialysis TCO₂  >29 mEq/L this number was reduced from 83 (98.8%) to 9 (10.7%). PTH significantly decreased from 226.09 (range 172–296) to 182.50 (125–239)  pg/mL at 6 months (P < 0.05) and post-dialysis potassium decreased from 3.16 ± 0.30 to 2.95 ± 0.48 mEq/L at 6 months (P < 0.05). Sodium, pre-dialysis potassium, calcium and phosphorous did not change significantly.

Conclusions

Reducing dialysate bicarbonate concentration by 3 mEq/L significantly and safely decreased pre- and post-dialysis TCO₂, avoiding acidosis overcorrection and improving secondary hyperparathyroidism control. An individualized bicarbonate prescription (a key factor in the adequate control of acidosis) according to pre-dialysis TCO₂ is suggested based on these results.

Cholangitis and pulmonary nodules in a clinical presentation of syphilis in an HIV-infected patient

Several clinical manifestations attributed to syphilitic infection have been described in the literature. This is important because of the increased incidence of this infection mainly among men who have sex with men. We report the case of an HIV-infected patient who was hospitalized due to severe cholestasis, initially interpreted as drug-induced liver disease. It evolved slowly, with increasing intrahepatic cholangitis confirmed by magnetic resonance cholangiography and the appearance of several pulmonary nodules. In lung and liver biopsies, the presence of Treponema pallidum was detected by molecular and immunohistochemistry techniques, and a diagnosis of cholangitis and pulmonary syphilis was made.