Maintenance Immunosuppression Research Articles

Prevalence of iron deficiency and anemia in pediatric heart transplant recipients.

The prevalence of iron deficiency and anemia in the setting of modern-day maintenance immunosuppression in pediatric heart transplant (HTx) recipients is unclear. The primary aim was to determine the prevalence of iron deficiency (serum ferritin<30ng/mL±transferrin saturation<20%) and anemia per World Health Organization diagnostic criteria and associated risk factors. Single-center, cross-sectional analysis of 200 consecutive pediatric HTx recipients(<21 years old) from 2005 to 2021. Data were collected at 1-year post-HTx at the time of annual protocol biopsy. Median age at transplant was 3 years (IQR.5-12.2). The median ferritin level was 32ng/mL with 46% having ferritin<30ng/mL. Median transferrin saturation (TSAT) was 22% with 47% having TSAT<20%. Median hemoglobin was 11g/dL with 54% having anemia. Multivariable analysis revealed lower absolute lymphocyte count, TSAT<20%, and estimated glomerular filtration rate<75mL/min/1.73m2 were independently associated with anemia. Ferritin<30ng/mL in isolation was not associated with anemia. Ferritin<30ng/mL may aid in detecting absolute iron deficiency while TSAT<20% may be useful in identifying patients with functional iron deficiency±anemia in pediatric HTx recipients. Iron deficiency and anemia are highly prevalent in pediatric HTx recipients. Future studies are needed to assess the impact of iron deficiency, whether with or without anemia, on clinical outcomes in pediatric HTx recipients.

#2859 Clinical and morphological characteristics of biopsy-proven kidney graft rejection in Latvia

Abstract Background and Aims Kidney transplantation is a treatment for many patients with end stage renal disease leading to increased quality of life. In last decades results in kidney transplantation have been improving, but allograft rejection remains an important clinical problem. Graft biopsy remains the gold standard to assess the cause of kidney transplant status. This study aimed to determine clinical and histopathological characteristics, treatment and short-term outcomes of biopsy-proved kidney graft rejection in Latvia. Method In this retrospective observational study all kidney allograft biopsies performed in Pauls Stradins Clinical University Hospital from January 2014 till December 2022 was reviewed. Biopsies with rejection, ≥7 glomeruli, patients ≥18 years old were included. Acute rejection was diagnosed according to clinical, laboratory and biopsy-proven acute rejection (BPAR) histological criteria. BPAR was classified and subdivided using Banff criteria. All recipients universally received either depleting or non-depleting induction therapy. Most of the patient (82%) for maintenance immunosuppression (MI) received triple therapy with calcineurin inhibitor, mycophenolate mofetil, and prednisone, others—in different combinations with above and mammalian target of rapamycin (mTOR), azathioprine. Graft function was evaluated according to glomerular filtration rate (GFR), calculated with the CKD-EPI Creatinine, 2021 equation. Treatment strategies, laboratory data at the time of biopsy and after 1 year follow-up were analysed. Repeated-control biopsies after receiving therapy were excluded. Data were analysed using descriptive statistics and T-test. Results From all 523 biopsies, further included and analysed were 153 (total 146 patients). 58% were males, average patient age was 45.5 years. Most 84% of the grafts were from deceased, 8%—living donors. Mean time from transplantation to biopsy was 32 months. Acute antibody-mediated rejection (AAMR) was diagnosed in 41% cases, chronic-active antibody mediated (CAAMR)—25%, followed by mixed 16%, acute cellular (ACR) 10% and borderline 8% rejection. Besides augmented MI for almost all patients, pulse steroids (GCS) were the most commonly 70% administered treatment, followed by plasma exchange 59% (PEX), rituximab (RTX) 50%, immunoglobulins (IG) 24% and anti-thymocyte globulin (ATG) 10% in different, mostly non-homogenous combinations. Non adherence, advanced fibrotic changes in biopsy and serious comorbidities were the main reasons patients did not receive specific treatment besides intensified MI. The most favourable outcomes were in ACR where mean allograft GFR increased +20.7 ml/min after one year, compared to the worst outcome CAAMR group where GFR decreased −4.7 ml/min (p = 0.03). In ACR group 92% graft function stayed the same or improved, moreover 54% graft function increased ≥20% from baseline; similarly in mixed and AAMR group GFR increase ≥20% were for 45% and 48%, compared to CAAMR where it was only for 6% of patient. Furthermore, the CAAMR group was with the most patients (48%) who returned to dialysis or died. In AAMR and mixed rejection groups mean GFR changes were close +13.4 ml/min and +12.9 ml/min (p = 0.95). There were no statistically significant associations between treatment outcomes in PEX+RTX+GCS vs PEX+RTX+GCS+IG in the AAMR group (p = 0.382). Overall, 3.9% of patients died. Conclusion Overall BPAR prevalence between kidney graft biopsies was high (29%). Antibody mediated rejection was diagnosed most often with least favourable short-term outcomes in CAAMR group. Despite various improvements in immunosuppression, CAAMR remains a serious cause of transplant dysfunction or loss.

#1888 Association between intrapatient variability of serum tacrolimus levels with the development of diabetes in post-kidney transplantation patients

Abstract Background and Aims Kidney transplantation is the most cost-effective renal replacement therapy compared to dialysis. Diabetes is main cause of increased cardiovascular risk and death. Post-transplant Diabetes Mellitus (PTDM) it refers to presence of diabetes in an environment after kidney transplantation; According to the ADA (American Diabetes Association) criteria, the diagnosis must be made with a tolerance test with 75 grams of oral glucose (Oral glucose tolerance test-OGTT) or the determination of glycosylated hemoglobin 1Ac (Hb1Ac) in a post-transplant period of stability of the immunosuppression dose and without infections. There are various risk factors for the development of PTDM: hypomagnesemia, glucocorticoids, calcineurin inhibitors (tacrolimus and cyclosporine); hepatitis C virus and cytomegalovirus infections. In a Mexican kidney transplant recipients in Guadalajara, Andrade SG demonstrated that the incidence of PTDM was 10.1% at 1 year post-transplant. In the Spanish population, Porrini E demonstrated that tacrolimus represents a risk factor for the development of PTDM, increasing the incidence of prediabetes by 33% at 12 months post-transplant. Several mechanisms have been implicated in the association of calcineurin inhibitor and PTDM: decreased insulin secretion, glucose intolerance, reduced pancreatic beta cell mass, increased islet apoptosis and decreased insulin gene expression. Studies mention that tacrolimus (FK) is more diabetogenic than cyclosporine (CsA) especially at levels above 20 ng/mL. The DIRECT study (Diabetes Incidence after Renal Transplantation) showed the incidence in 73 kidney transplant patients with CsA (26%) and 96 FK patients (33.6%, p = 0.046). By the other side, Malik RF mentions that FK levels aren´t a risk factor for the development of PTDM. To demonstrate that the high intrapatient variability of tacrolimus/cyclosporine serum levels correlates with the development of diabetes (PTDM) in kidney transplant recipients at the central military hospital in Mexico City. Method Observational, analytical, longitudinal and retrospective study. All kidney transplant recipients from living donors and cadaveric donors from January 2002 to December 2020 were included. FK and CsA were used as maintenance immunosuppression. Serum levels of FK/CsA, Hb1Ac and glucose were measured at months 0, 3, 6, 9 and 12 and intra-patient variability (IPV) of FK/CsA levels was calculated for each patient. The patients were separated into 2 groups, IPV low and IPV high according to the mean the coefficient of variability (CV). The IPV of the calcineurin inhibitor was estimated by calculating the CV in each patient according to the following equation: CV(%)= (SD/mean trough concentration of FK/ CsA)×100. The diagnosis of PTDM followed the criteria of the American Diabetes Association. The Mann Whitney U test was used. Results 638 kidney transplant recipients were included. The mean age of the recipients was 36.78 (±12.81) years. At the time of kidney transplant, the BMI was 22.67 (±3.90) and 25.76 (±3.99) kg/m² BS at 1 year post-transplant for whole cohort. At 1 year post-transplant, 72.3% patients were on FK and 27.7% on CsA. Hb1Ac for whole cohort was 4.81 (±0.71)% and 4.84 (±0.77)% at month 0 and 12 post-kidney transplant, respectively. FK and CsA levels were 12.41 (±5.31) and 234.34 (±87.80) ng/mL and 9.13 (±5.3) and 194.38 (±92.44) ng/mL in the PTDM and non-PTDM groups, respectively (p = 0.029). 17.96% of patients developed PTDM. Mean CV of the entire cohort was 33.84 (±20.41)%. When performing the analysis of the IPV coefficient by subgroups of maintenance immunosuppression used at 1 year post-transplant: the IPV of FK was 43.39 (±18.49)% and 29.99 (±17.56)% in the PTDM and non-PTDM groups respectively, p = 0.000, which shows that patients with a high IPV coefficient of tacrolimus developed more PTDM than those with low variability, student's t-test to compare IPV was 0.03. The IPV of CsA was 38.61 (±18.76)% and 37.51 (±25.67)% in the PTDM and non-PTDM groups respectively, p = 0.819. Conclusion High intrapatient variability of tacrolimus was correlated with the development of PTDM in Mexican kidney transplant recipients.

#2403 Impact of pregnancy on kidney transplant recipients

Abstract Background and Aims Kidney transplantation (KT) provides an opportunity to increase fertility in women with chronic kidney disease and gestational desire. Lack of knowledge about obstetric complications and implications for the graft may lead to discourage pregnancy for these women. Although the incidence of pregnancy is rising in women receiving KT, the impact that it may have on the graft function is unknown. Method We conducted an observational, retrospective, single-centre study of a cohort of kidney transplant recipients (KTR) who became pregnant between 2007 and 2022. Clinical and analytical parameters were evaluated before, during and after pregnancy. The main aim was to assess the long-term impact of pregnancy on the graft by analysing renal function 3 years after pregnancy. Results We included 25 women receiving a KT between 1990 and 2018, among which 72% (n = 18) were transplanted from a deceased donor. 2 women (8%) received a combined liver-kidney transplant and 2 women (8%) a simultaneous pancreas-kidney transplant. Maintenance immunosuppression before conception included teratogenic drugs in 68% of cases [12 of them (48%) received mycophenolate mofetil and 5 of them (20%), mTOR inhibitors]. Planned withdrawal was only applied in 50.0% of pregnancies (n = 15). 30 pregnancies were identified (5 patients had 2 post-transplant pregnancies). Median age at gestation was 35 years [interquartile range (IQR) 33-39]. 5 conceptions required assisted reproductive technology. The main complications were gestational hypertension in 4 KTR (13.3%) and preeclampsia in 7 pregnancies (23.3%). 60% of neonates (n = 18) were preterm births (36 [IQR 34-37] weeks of pregnancy at birth) and 44% (n = 12) had low birth weight (2530 [IQR 2283-2950] grams). No foetal malformations were described. Due to physiological changes, a significant increase in estimated glomerular filtration rate (eGFR) was observed in the first and the second trimester of pregnancy (61 [IQR 50-91] ml/min and 70 [IQR 50-90] ml/min, respectively vs. baseline eGFR 59 [IQR 47-77] ml/min; p 0.001]. However, eGFR was equal to the previous one in the third trimester of pregnancy (60 [IQR 44-69] ml/min vs. 59 [IQR 47-77] ml/min; p 0.322). Median proteinuria remained below 0.5 g/day throughout pregnancy, without significant variation. Immunosuppression regimen during pregnancy was mainly based on a combined therapy of steroids, calcineurin inhibitors and azathioprine (21 KTR, 70%). Tacrolimus dose increase (median 63.6% [IQR 33.3-90.0%]) was necessary to maintain proper drug levels throughout gestation. Kidney graft function showed a decline in the first and second year after pregnancy compared to baseline function (54 [IQR 35-77] ml/min and 55 [IQR 36-75] ml/min vs. 59 [IQR 47-77] ml/min; p 0.018 and p 0.021, respectively]. Nevertheless, by the third year post-pregnancy, eGFR was similar to the baseline function (62 [IQR 43-73] ml/min vs. 59 [IQR 47-77] ml/min; p 0.365]. Likewise, annual eGFR variation was comparable during 3 years before (+1.0 ml/min/year) and 3 years after pregnancy (−0.9 ml/min/year), hence no worsening was observed after gestation (p 0.78). No differences were observed in proteinuria either (baseline proteinuria 0.17 [IQR 0.13-0.3] g/day vs. third-year proteinuria 0.21 [IQR 0.15-0.34] g/day; p 0.938). Only 5 women had a baseline serum creatinine above current recommendations for pregnancy (&amp;gt;1.5 mg/dl) and only 3 women presented baseline proteinuria &amp;gt; 0.5 g/day. In this group (n = 7), pregnancy occurred later after KT (96.0 [IQR 80.9-213.0] vs. 46.0 [IQR 16.0-67.5] months; p 0.024). The only 2 graft losses in the cohort were in this group. Both were attributed to transplant glomerulopathy, and they occurred at years 3 and 5 after pregnancy. On the other side, in this group there were no other baseline differences or obstetrical complications [Table 1]. Conclusion Pregnancy does not normally affect graft function and it stabilises within 3 years after gestation. It is important to increase data on women with suboptimal graft function to determine the direct implications that pregnancy may have on these KTRs.

#2149 Kidney transplantation outcomes in lupus nephritis

Abstract Background and Aims Kidney transplantation (KT) is the renal replacement therapy of choice in patients with lupus nephritis (LN) who progress to end-stage renal disease (ESRD). The latest Spanish guidelines recommend the use of hydroxychloroquine after KT in these patients. Our study aims to analyze KT outcomes in patients with LN in our center. Method Retrospective cohort study, which included all KT with a diagnosis of LN who underwent KT between April 1982 and November 2023 at Puerta del Mar University Hospital (Spain). Each KT recipient with LN was matched with two controls from the same institution by age, sex and type of donor during the same period. We collected clinical and demographical characteristics, as well as immunosuppressive (IS) therapy after KT. We analyzed the death-censored graft survival and patient survival and compiled the causes of death and graft loss, comparing them with the control group. We documented LN recurrences, KT rejections, and incidence of CMV and BK infection. Results In this period, 2055 KTs were performed in our center, of which 39 had a diagnosis of LN (1.9%). Seventy eight controls were selected. The majority of KTs were women (89.7%) with a mean age of 44 years. Induction therapy was used in 85.2% of KT with Thymoglobulin (63%) or Basiliximab (27%). Maintenance IS therapy was based on tacrolimus (93.5%), cyclosporine (6.5%), mycophenolate (100%) and prednisone (100%). Only 4 patients (10.2%), the latest ones, received hydroxychloroquine after KT. Death-censored graft survival at 1 year (87.1% SLE vs. 88.5% Non-SLE), 5 years (74.9% SLE vs. 80.8% Non-SLE), and 10 years (65.6% SLE vs. 69.5% Non-SLE) and patient survival at 1 year (97.1% SLE vs. 100% Non-SLE), 5 years (93.7% SLE vs. 95.3% Non-SLE), and 10 years (93.7% SLE vs. 91.7% Non-SLE) were similar in both groups. No graft was lost because of recurrent LN. No significant differences were found neither in the causes of death nor between the causes of graft loss. The incidence of CMV and BK infection and KT rejection rates were similar in both groups. Conclusion KT is an excellent therapeutic alternative in LN with ESRD. Despite the low use of hydroxychloroquine in our series, no recurrence of LN was detected and the KT outcomes were similar to the control group.

#2362 Clinical utility Anti-human T-lymphocyte Immunoglobulin (ATLG) as an induction agent in a living donor kidney transplantation: 5-year follow-up data

Abstract Background and Aims The usage of induction agents for living donor kidney transplants in India is varied. Polyclonal antibodies currently in use are anti-thymocyte globulin (ATG) and anti-T-lymphocyte globulin (ATLG). The role and dose of ATLG need to be defined. This study is focused on ATLG usage and the outcome with long-term follow-up. Method This is an analysis of 206 patients who received ATLG as an induction agent from 2017 to 2023. Patients received triple immunosuppression therapy: Tacrolimus, Mycophenolate Mofetil (MMF), and prednisolone for maintenance immunosuppression. Results A total of 206 patients received ATLG as an induction agent for living donor kidney transplants. The mean age of the patients was 39.13 ± 12.56 years. There were 87.3% (n = 180) males and 12.6% (n = 26) females. The majority of transplants in our study were ABO-compatible (94.6%, n = 195) and ABO-incompatible (5.2%, n = 11). The mean age of donors was 41 ± 13.7 years. Males were 38.3% (n = 79), and females were 61.6% (n = 127). Overall survival observed in the current study was 98% (n = 202), Post-transplant, 4 patients died (n = 2 died due to COVID-19, 1 due to Heart failure and 1 was infectious mortality.) The mean cumulative dose of ATLG in the current study was 305.1 ± 61.8 mg, and the mean dose was 5.4 ± 1.4 mg/kg. The baseline etiologies of patients who underwent transplant were chronic glomerulonephritis (47.5% n = 98), diabetic nephropathy (16.9% n = 35), hypertension (29.1% n = 60), CIN, and other GMB diseases. In the current study, the figure shows overall 11.6% (n = 24) rejections and 5-year follow-up data of Serum creatinine within a normal range. Post-transplant BK Virus Nephropathy was observed in 3.39% (n = 7) cases, CMV infection in two cases, TB was observed in three cases and fungal pneumonia in one case. Conclusion Long-term 5 year follow-up of Living donor kidney transplant shows that ATLG is an effective and safe induction agent. Good compliance with Oral immunosuppressant can improve graft survival as per the current study.

#3052 mTOR inhibitors in kidney transplant recipients with high immunological risk: practical insights from clinical experience

Abstract Background and Aims The use of mTOR inhibitors (mTORi) is not usually considered in high immunological risk kidney transplant recipients (KTR) for a perceived increased risk of rejection. However, in most of the studies that examined the combination of mTORi with calcineurin inhibitors (CNI), hypersensitized patients have been excluded from enrollment. The aim of the present study is to analyze our clinical experience with the use of mTORi in association with calcineurin inhibitors (CNI) in this subset of patients. Method Analysis of 212 consecutive kidney transplant recipients with a baseline calculated panel reactive antibody (cPRA) ≥50% who received a graft from June 2013 to December 2019. Immunosuppression was based on tacrolimus, steroids and, alternatively, mycophenolic acid (MPA; n = 96) or mTORi (either sirolimus or everolimus, target trough levels 3-8 ng/ml, n = 116) depending on the active Institution's protocol at the time of transplantation. The outcomes chosen included rejection-free, graft and patient survival and were analyzed by means of Cox-regression analysis. Results Demographic and immunological characteristics were similar between groups, apart from the higher number of living donors in the MPA group (42.7% vs 14.7%%, P &amp;lt; 0.001). Baseline cPRA was 92.5 [76-98]% for the MPA and 94 [77.25-98]% for the mTORi group, respectively (P = 0.882). Induction therapy with lymphocyte-depleting agents was employed in the majority of patients (91.7% in the MPA group and 88.8% in the mTORi group, P = 0.898). Median follow-up time was 2.6 [1.45-4.05] years. Biopsy-proven rejection (either cellular or humoral) occurred in 33.3% of the MPA and in 19.8% of the mTORi group, respectively. Cox-regression analysis of rejection-free survival revealed better rejection-free survival with mTORi versus MPA (HR [95% CI], 0.54 [0.32-0.98], P = 0.028). The only other baseline factor associated with rejection was previous transplantation (HR [95% CI] 1.96 [1.07-3.60], P = 0.030). When entered into a bivariable Cox-regression analysis, both mTORi and previous transplantation maintained a statistical significant association with rejection (mTORi versus MPA HR [95% CI] 0.53 [0.31-0.91], P = 0.023, and previous transplantation HR [95% CI] 2.01 [1.09-3.69], P = 0.024). No differences between mTORi and MPA were noted for graft (HR [95% CI] 0.90 [0.40-2.02], P = 0.807) and patient survival (HR [95% CI] 1.23 [0.60-2.50, P = 0.606). Median creatinine 1 year after transplantation was 1.45 [1.11-1.98]mg/dl for the MPA group and 1.51 [1.09-2.06]mg/dl for the mTORi group (P = 0.917). Conclusion This retrospective study suggests that hypersensitized KTRs can receive safely a maintenance immunosuppression based on a combination of CNI with mTORi, without an increased risk of rejection.

#2684 Free light chains levels in ANCA associated vasculitis: a new potential inflammatory biomarker

Abstract Background and Aims Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is a systemic disease characterized by an immune-mediated process where inflammation plays a central role. The widely available serum biomarkers of inflammation are not always able to detect ongoing disease activity in ANCA-associated vasculitis (AAV) patients. Free light chains (FLCs) expression levels have been proposed as new promising biomarker in some immune-mediated and inflammatory diseases. The aim of this study is to evaluate the expression levels of FLCs in patients affected by AAV and investigate the potential effect of rituximab treatment on FLCs levels. Method We conducted a retrospective multicenter study enrolling AAV patients in complete remission of AAV (defined as BVAS/GPA = 0); those with clinical suspicion of underlying hematologic malignancy were excluded. We analyzed κ and λ FLCs serum concentrations and evaluated their correlation with biomarkers of immune system activation, such as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), serum immunoglobulin (Ig) levels, serum C3 and C4 complement and albumin levels (which has a negative correlation with acute inflammatory phase). We assessed impact of rituximab (RTX) therapy within the last 6 months on the same laboratory parameters. Results A total of 137 patients with AAV were recruited, who were gender balanced, had an average age of 68 years and an estimated glomerular filtration rate of 68 (43-89) mL/min/1.73 m2. Fifty-one patients received rituximab treatment (RTX group), while 86 patients were on other immunosuppressive maintenance therapies (non-RTX group). In comparison to non-RTX group, patients treated with RTX experienced higher complement C3 levels, lower ESR levels and lower FLCs κ (p = 0.063) and λ (p = 0.013) levels. The differences between RTX and non-RTX groups in terms of FLCs were even more prominent after correction to total Ig concentration (p = 0.004 for κ /Ig and p = 0.003 for λ /Ig, respectively). Both, serum free κ and λ levels were found to correlate significantly with ESR (R = 0.55 and p &amp;lt; 0.001 for κ; R = 0.53 and p &amp;lt; 0.001 for λ) and albumin (R = ‒0.38 and p &amp;lt; 0.001 for κ; R = ‒0.33 and p &amp;lt; 0.001 for λ). Additionally, serum free κ levels showed an inverse association with C3 (R = ‒0.18 and p = 0.041). Conclusion In subjects with AAV, FLC levels were found to be associated with markers of inflammation and complement activation; hence FLCs levels may represent a promising biomarker for detection of subclinical inflammation in AAV patients on maintenance therapy. Rituximab therapy showed a potential to reduce the levels of markers of subclinical inflammation, including FLCs.

Remission and low disease activity are associated with lower healthcare costs: results from the Systemic Lupus International Collaborating Clinics (SLICC) inception cohort

ObjectivesThis study aims to determine the independent impact of definitions of remission/low disease activity (LDA) on direct/indirect costs (DCs, ICs) in a multicentre inception cohort.MethodsPatients from 31 centres in 10...

Belatacept based immunosuppression: What and when to combine?

IntroductionThis study examines the effect of belatacept based salvage regimens on kidney transplant outcomes. MethodsThis single-center retrospective study included all adult kidney transplant recipients between 2011 and 2022 who were converted to belatacept salvage therapy during their follow up. eGFR, graft survival, incidence of infections and neoplasia, histology and DSA data were collected through systematic review of the medical record. ResultsPatients were divided into 3 groups based on salvage regimen: Mycophenolate mofetil/belatacept (MMF/Bela) (n = 28), low-dose Calcineurin inhibitors/belatacept (CNI/Bela) (n = 22), and low-dose Calcineurin inhibitors/ Mycophenolate mofetil /belatacept (CNI/MMF/Bela) (n = 13). Patients with antibody-mediated rejection were more likely to receive CNIs in addition to belatacept (low-dose CNI/MMF/Bela 54%, low-dose CNI/Bela 45%, MMF/Bela 3.6%, p < 0.001). DSA decreased in all groups after transition to belatacept by 15.67% (p = 0.15). No difference in Glomerular filtration rate (eGFR) over time was observed between the groups, and eGFR remained stable over the first year after transition to belatacept. The incidence of death and allograft failure was similar between the groups (low- dose CNI/MMF/Bela n = 3, low-dose CNI/Bela n = 7, MMF/Bela n = 4; p = 0.41). Patients in the low-dose CNI/Bela cohort who were transitioned to belatacept within 6 months from transplant showed a decline in eGFR over the first year after transition, while the other treatment cohorts demonstrated stable or slight increase in eGFR. ConclusionsThe present study demonstrates comparable transplant outcomes in terms of eGFR, graft survival, incidence of infections and neoplasia, rejection rate and donor specific antibody (DSA) in three belatacept-based maintenance immunosuppression regimens supporting the safety and efficacy of these therapeutic options.

Autoimmune hepatitis presenting as severe anemia

AbstractAutoimmune hepatitis (AIH) is relatively rare in children. Herein, our case demonstrates a unique presentation of AIH in a previously healthy 18‐year‐old female presenting with a mild cough, fatigue, and severe anemia (hemoglobin 2.9 g/dL). Initial evaluation revealed jaundice and scleral icterus, prompting transfer of care and further testing, which demonstrated severe microcytic anemia, pancytopenia, elevated liver enzymes, direct hyperbilirubinemia, and marked splenomegaly. Concern for autoimmune hemolytic anemia resulted in a delayed diagnosis. The combination of triple antibody positivity (anti‐nuclear antibodies, anti‐actin, and anti‐liver‐kidney microsomal‐1) and liver histology findings confirmed the diagnosis of AIH. Intravenous methylprednisolone was initiated to induce remission. Due to pancytopenia and persistently elevated INR, tacrolimus was chosen as the maintenance immunosuppression instead of azathioprine. This case highlights several significant considerations for clinicians, including the importance of a timely clinicopathologic diagnosis, the severe anemia presentation secondary to hypersplenism, and the rare finding of triple autoantibody‐positive AIH.

Long-term outcomes of two-dose alemtuzumab induction in pediatric kidney transplantation.

Alemtuzumab is a lymphocyte depleting agent used for induction in kidney transplant, but long-term information on its use in pediatric recipients remains sparse. We performed a single-center retrospective cohort study of 57 pediatric kidney transplant recipients receiving alemtuzumab 20 mg/m2/dose ×2 doses for induction immunosuppression. All patients underwent surveillance biopsies, and 91.3% underwent steroid withdrawal by day 4 post-transplant. Outcomes of interest included graft survival, development of donor specific antibodies (DSA), incidence of viremia and PTLD, and duration of lymphopenia. Median follow-up time was 7.9 years (IQR 5-13.6 years). Median graft survival was 16.5 years (95% CI 11.6-unknown). DSA developed in 36.5% at a median of 944 days (IQR 252-2113 days). Incidences of BK polyomavirus DNAemia (BKPyV-DNAemia), CMV DNAemia, and EBV DNAemia were 38.6%, 22.8%, and 14%, respectively; one patient developed PTLD at 13.3 years post-transplant. Median duration of lymphopenia was 365 days (IQR 168-713 days); 19.3% of patients remained lymphopenic at 3 years post-transplant. There was no association between duration of lymphopenia and graft survival, rejection, DSA detection, or viremia. A two-dose alemtuzumab induction protocol can have excellent outcomes with a steroid-free maintenance immunosuppression regimen. More comprehensive, multicenter, comparative studies of pediatric kidney transplant are needed to improve long-term outcomes.

Clinical relevance of HLA-DQ eplet mismatch and maintenance immunosuppression with risk of allosensitization after kidney transplant failure.

The optimal immunosuppression management in patients with a failed kidney transplant remains uncertain. This study analyzed the association of class II HLA eplet mismatches and maintenance immunosuppression with allosensitization after graft failure in a well characterized cohort of 21 patients who failed a first kidney transplant. A clinically meaningful increase in cPRA in this study was defined as the cPRA that resulted in 50% reduction in the compatible donor pool measured from the time of transplant failure until the time of repeat transplantation, death, or end of study. The median cPRA at the time of failure was 12.13% (interquartile ranges = 0.00%, 83.72%) which increased to 62.76% (IQR = 4.34%, 99.18%) during the median follow-up of 27 (IQR = 18, 39) months. High HLA-DQ eplet mismatches were significantly associated with an increased risk of developing a clinically meaningful increase in cPRA (p = 0.02) and de novo DQ donor-specific antibody against the failed allograft (p = 0.02). We did not observe these associations in patients with high HLA-DR eplet mismatches. Most of the patients (88%) with a clinically meaningful increase in cPRA had both a high DQ eplet mismatch and a reduction in their immunosuppression, suggesting the association is modified by immunosuppression. The findings suggest HLA-DQ eplet mismatch analysis may serve as a useful tool to guide future clinical studies and trials which assess the management of immunosuppression in transplant failure patients who are repeat transplant candidates.

Efficacy and Safety of Bleselumab in Preventing the Recurrence of Primary Focal Segmental Glomerulosclerosis in Kidney Transplant Recipients: A Phase 2a, Randomized, Multicenter Study.

Focal segmental glomerulosclerosis (FSGS) is a common cause of end-stage kidney disease and frequently recurs after kidney transplantation. Recurrent FSGS (rFSGS) is associated with poor allograft and patient outcomes. Bleselumab, a fully human immunoglobulin G4 anti-CD40 antagonistic monoclonal antibody, disrupts CD40-related processes in FSGS, potentially preventing rFSGS. A phase 2a, randomized, multicenter, open-label study of adult recipients (aged ≥18 y) of a living or deceased donor kidney transplant with a history of biopsy-proven primary FSGS. The study assessed the efficacy of bleselumab combined with tacrolimus and corticosteroids as maintenance immunosuppression in the prevention of rFSGS >12 mo posttransplantation, versus standard of care (SOC) comprising tacrolimus, mycophenolate mofetil, and corticosteroids. All patients received basiliximab induction. The primary endpoint was rFSGS, defined as proteinuria (protein-creatinine ratio ≥3.0 g/g) with death, graft loss, or loss to follow-up imputed as rFSGS, through 3 mo posttransplant. Sixty-three patients were followed for 12 mo posttransplantation. Relative decrease in rFSGS occurrence through 3 mo with bleselumab versus SOC was 40.7% (95% confidence interval, -89.8 to 26.8; P = 0.37; absolute decrease 12.7% [95% confidence interval, -34.5 to 9.0]). Central-blinded biopsy review found relative (absolute) decreases in rFSGS of 10.9% (3.9%), 17.0% (6.2%), and 20.5% (7.5%) at 3, 6, and 12 mo posttransplant, respectively; these differences were not statistically significant. Adverse events were similar for both treatments. No deaths occurred during the study. In at-risk kidney transplant recipients, bleselumab numerically reduced proteinuria occurrence versus SOC, but no notable difference in occurrence of biopsy-proven rFSGS was observed.

The humoral immune response to the BNT 162B2 vaccine in pediatrics on renal replacement therapy.

Since the start of the COVID-19 pandemic, data published on the immunogenicity of the SARS-CoV-2 BNT 162B2 vaccine in pediatric patients receiving renal replacement therapy are scant. Our primary objective is to study this population's humoral immune response to the COVID-19 vaccine. Pediatric kidney transplant recipients (PKTRs) and hemodialysis recipients (HR) at our center who received two doses of the SARS-CoV-2 BNT 162B2 vaccine were included. Transplant and HR who had PCR-positive COVID-19 infections during the study, regardless of their vaccine status, were also included. SARS-CoV-2 anti-spike protein (S1/S2) IgG was measured after the second dose of the vaccine and after any PCR-positive COVID-19 infection as routine clinical practice. Data on demographics, induction, maintenance immunosuppressants, type of transplant, and posttransplant or dialysis duration were included. Of the 61 patients included, 19 were dialysis recipients who received two doses of vaccine without subsequent infection (HV), and 42 were kidney transplant recipients. All dialysis patients and 33 (78.6%) transplant recipients received two doses of the SARS-CoV-2 BNT 162b2 vaccine. A total of 33.3% (11/33) of the transplant recipients who received vaccination developed COVID-19 infection (KTH) at a median time of 13 days after the second dose of vaccine. Nine transplant patients had pure COVID-19 infection without vaccination (KTI). The seroconversion rate in the HV group was 94.7% (18/19) compared to 50% (11/22) in the kidney transplant vaccine recipients who did not develop subsequent COVID-19 infection (KTV) (p < .001). The median S1/S2 IgG titers for the HV group were 400 AU/mL versus 15 AU/mL in the KTV group (p < .0001). There was no significant difference in the duration of the test from the second dose of the vaccine between HV and KTV (55 vs. 33.5 days, p = .095). The KTH had higher titers than KTV group (370 vs. 15 p < .0001). The median duration of the test after vaccination in the vaccine group and those with hybrid immunity was similar (35 vs. 33.5 days, p = .2).There were no clear predictors for seroconversion in the PKTRs. Natural infection alone was as good as the vaccine in eliciting humoral immune response. The humoral immune response to two doses of the SARS-CoV-2 BNT 162B2 vaccine in PKTRs without subsequent COVID-19 infection is suboptimal compared to that in hemodialysis recipients and in PKTRs with hybrid immunity from both infection and vaccination.

Anti-N-methyl-D-aspartate Receptor Encephalitis in People Living with HIV: Case Report and Literature Review.

With the increase in the number of cases of autoimmune encephalitis (AE), the cerebrospinal fluid (CSF) of people living with HIV (PLWH) showing abnormal behavior, cognitive impairment or abnormal movements should be actively screened for the antibody panel of AE. Early recognition and treatment can prevent severe seizures or coma and markedly improve the prognosis of patients. The first-line immunotherapy for AE includes intravenous methylprednisolone and immunoglobulin. However, whether long-time immunosuppressive maintenance therapy is needed is debated. For PLWH, immunosuppressive therapy and even steroids could be more challenging. Here, we review and summarize the clinical characteristics often reported cases and report one case from our center to improve the diagnosis and treatment of anti-N-methyl-D-aspartate receptor encephalitis in PLWH.

Histoplasma capsulatum tenosynovitis: An unusual presentation in a kidney transplant recipient.

Histoplasmosis is an expected endemic mycosis in solid organ transplant recipients and occurs as a primary infection, reactivation, or, rarely, acquired from an infected allograft. Reactivation is favored by maintenance immunosuppression or anti-rejection therapy, which facilitates the appearance of disseminated forms as well as unusual presentations. We present the case of a 66-year-old woman with isolated tenosynovitis due to Histoplasma capsulatum 25 years after a kidney transplant.

Medical Maintenance Therapy Following Laser Excision in Patients With Granulomatosis With Polyangiitis (GPA)-Associated Subglottic Stenosis.

To report on a series of patients with cANCA/PR3-positive, granulomatosis with polyangiitis (GPA)-associated subglottic stenosis (SGS) and evaluate response to medical maintenance therapy with rituximab versus other immunosuppressants following initial endoscopic laser excision. Retrospective chart review. Tertiary academic center. A retrospective chart review of patients with SGS and cANCA/PR3-positive GPA who received immunosuppressive maintenance therapy following endoscopic laser excision at our institution from June 1989 to March 2020 was performed. Data pertaining to patient demographics, clinical features, medications, and endoscopic laser procedures were collected. A total of 27 patients (15 women) with mean age (range) of 40 (19-59) years and mean (range) follow-up of 12.6 years (1.5-28.6) were identified. Sixteenpatients (60%) had limited GPA. Six patients (24%) had previously received local intervention with open surgery (n = 1, 4%) or endoscopic techniques (n = 5, 20%). All patients experienced symptom improvement following initial CO2 laser excision at our institution without any procedural complications or adverse events. Following initial laser excision, 15 patients (60%) were treated with rituximab and 10 patients (40%) were treated with nonrituximab immunosuppressive agents. Patients treated with rituximab were less likely to recur (P = 0.040). Limited GPA was associated with an increased incidence of recurrence (P = 0.031). Median time (years) to recurrence (range) was 3.2 (0.3-19.3) and was not significantly associated with treatment or GPA subtype. Endoscopic CO2 laser excision is a safe and effective local intervention for GPA-associated SGS. Medical maintenance therapy with rituximab reduces risk of recurrence following initial laser excision relative to treatment with non-rituximab agents.

Impact of Cumulative 6 mg/kg Antithymocyte Globulin on Early Posttransplant Outcomes in Kidney Transplant Recipients with Delayed Graft Function.

Introduction: Delayed graft function in kidney transplant is associated with an increased risk of rejection and graft loss. Use of rabbit antithymocyte globulin induction in delayed graft function has been correlated with less rejection compared to basiliximab, but optimal dosing remains unknown. Program Evaluation Aims: The purpose of this evaluation was to retrospectively assess the short-term effectiveness and tolerability of a clinical protocol that increased the net state of immunosuppression in delayed graft function kidney transplant recipients using cumulative 6 mg/kg rabbit antithymocyte globulin induction. Design: This retrospective cohort included 88 kidney transplant recipients with delayed graft function, transplanted between January 2017 and March 2021, who either received cumulative 4.5 mg/kg pre-protocol or 6 mg/kg post-protocol rabbit antithymocyte globulin. Outcomes evaluated were biopsy-proven acute rejection and incidence of graft loss, infection, and cytopenia at 6 months. Results: A significant reduction of biopsy-proven acute rejection incidence occurred post-protocol implementation (10/33, 30.3% vs 6/55, 10.9%; P = .04). Of those with rejection, significantly less post-protocol patients were classified as acute cellular rejection (9/10, 90.0% vs 2/6, 33.3%; P = .04). No death-censored graft loss was observed in either group. Rates of cytopenia and infection were similar pre- versus post-protocol implementation. Conclusion: Increasing the exposure to rabbit antithymocyte globulin and maintenance immunosuppression in delayed graft function kidney transplant recipients was tolerable and significantly reduced rejection occurrence at 6 months.

A GC-MS-based untargeted metabolomics approach for comprehensive metabolic profiling of mycophenolate mofetil-induced toxicity in mice.

Background: Mycophenolate mofetil (MMF), the morpholinoethyl ester of mycophenolic acid, is widely used for maintenance immunosuppression in transplantation. The gastrointestinal toxicity of MMF has been widely uncovered. However, the comprehensive metabolic analysis of MMF-induced toxicity is lacking. This study is aimed to ascertain the metabolic changes after MMF administration in mice. Methods: A total of 700mg MMF was dissolved in 7mL dimethyl sulfoxide (DMSO), and then 0.5mL of mixture was diluted with 4.5mL of saline (100mg/kg). Mice in the treatment group (n = 9) were given MMF (0.1mL/10g) each day via intraperitoneal injection lasting for 2weeks, while those in the control group (n = 9) received the same amount of blank solvent (DMSO: saline = 1:9). Gas chromatography-mass spectrometry was utilized to identify the metabolic profiling in serum samples and multiple organ tissues of mice. The potential metabolites were identified using orthogonal partial least squares discrimination analysis. Meanwhile, we used the MetaboAnalyst 5.0 (http://www.metaboanalyst.ca) and Kyoto Encyclopedia of Genes and Genomes database (http://www.kegg.jp) to depict the metabolic pathways. The percentages of lymphocytes in spleens were assessed by multiparameter flow cytometry analysis. Results: Compared to the control group, we observed that MMF treatment induced differential expression of metabolites in the intestine, hippocampus, lung, liver, kidney, heart, serum, and cortex tissues. Subsequently, we demonstrated that multiple amino acids metabolism and fatty acids biosynthesis were disrupted following MMF treatment. Additionally, MMF challenge dramatically increased CD4+ T cell percentages but had no significant influences on other types of lymphocytes. Conclusion: MMF can affect the metabolism in various organs and serum in mice. These data may provide preliminary judgement for MMF-induced toxicity and understand the metabolic mechanism of MMF more comprehensively.