Javier Roberti

Preconditioning donor with a combination of tacrolimus and rapamacyn to decrease ischaemia–reperfusion injury in a rat syngenic kidney transplantation model

Reperfusion injury remains one of the major problems in transplantation. Repair from ischaemic acute renal failure (ARF) involves stimulation of tubular epithelial cell proliferation. The aim of this exploratory study was to evaluate the effects of preconditioning donor animals with rapamycin and tacrolimus to prevent ischaemia–reperfusion (I/R) injury. Twelve hours before nephrectomy, the donor animals received immunosuppressive drugs. The animals were divided into four groups, as follows: group 1 control: no treatment; group 2: rapamycin (2 mg/kg); group 3 FK506 (0, 3 mg/kg); and group 4: FK506 (0, 3 mg/kg) plus rapamycin (2 mg/kg). The left kidney was removed and after 3 h of cold ischaemia, the graft was transplanted. Twenty‐four hours after transplant, the kidney was recovered for histological analysis and cytokine expression. Preconditioning treatment with rapamycin or tacrolimus significantly reduced blood urea nitrogen and creatinine compared with control [blood urea nitrogen (BUN): P < 0·001 versus control and creatinine: P < 0·001 versus control]. A further decrease was observed when rapamycin was combined with tacrolimus. Acute tubular necrosis was decreased significantly in donors treated with immunosuppressants compared with the control group (P < 0·001 versus control). Moreover, the number of apoptotic nuclei in the control group was higher compared with the treated groups (P < 0·001 versus control). Surprisingly, only rapamycin preconditioning treatment increased anti‐apoptotic Bcl2 levels (P < 0·001). Finally, inflammatory cytokines, such as tumour necrosis factor (TNF)‐α and interleukin (IL)‐6, showed lower levels in the graft of those animals that had been pretreated with rapamycin or tacrolimus. This exploratory study demonstrates that preconditioning donor animals with rapamycin or tacrolimus improves clinical outcomes and reduce necrosis and apoptosis in kidney I/R injury.

Donor preconditioning with rabbit anti-rat thymocyte immunoglobulin ameliorates ischemia reperfusion injury in rat kidney transplantation.

A major concern in transplantation is the preservation of organ function. Ischemia time and microcirculatory disturbance of the organ cannot be avoided and may result in ischemia reperfusion injury (IRI), increasing the risk of delayed graft function (DGF) and acute and chronic rejection. Anti-thymocyte immunoglobulin (rATG) is a polyclonal antibody preparation with multiple effects when administered to recipients. Our objective has been to evaluate whether the administration of rATG to kidney donors instead of recipients, in an experimental model of syngeneic rat transplantation, ameliorates IRI and facilitates immediate graft function recovery. Urea and creatinine levels and necrosis severity scores were significantly lower in kidneys from donors that had received rATG (urea: control: 211±8mg/dl vs. treatment: 110±15mg/dl, p<0.001; creatinine: control: 4.6±0.24mg/dl vs. treatment: 2.6±0.22mg/dl, p<0.001; necrosis severity scores: control: 2.3 vs. treatment: 1.6, p<0.05). TUNEL staining showed 80±13 positive cells in control group and 9±3 (p<0.001) in treatment group. In situ expression of proinflammatory cytokines TNF-α, IL-6, IL-21 and TGF-β1 was reduced in rATG group (p<0.01); the same was observed for KIM-1 and caspase 8 (p<0.001). Cytoprotective genes Bcl2 and HO-1 were upregulated in situ in treatment group (p<0.001). In situ expression of IL-17, caspase 9, IL-23a, CxCl3 and ICAM1 showed no difference between groups (p>0.05). Findings suggest ATG administered to donors may ameliorate the IRI process in kidney transplantation, expressed by lower necrosis and apoptosis scores and the improvement of renal function, which may be explained through the diminished in situ expression of inflammatory mediators.

Use of Belatacept as Alternative Immunosuppression in Three Renal Transplant Patients with De Novo Drug-Induced Thrombotic Microangiopathy

Thrombotic microangiopathy (TMA), a severe complication of renal transplantation, is a pathological process involving microvascular occlusion, thrombocytopenia, and microangiopathic hemolytic anemia. It generally appears within the first weeks after transplantation, when immunosuppressive drugs are used at high doses. De novo TMA may also be drug-induced when calcineurin inhibitors or proliferation signal inhibitors are used. We report three cases of de novo drug-induced TMA in renal transplant patients who were managed by replacing calcineurin inhibitors or proliferation signal inhibitors with belatacept, a primary maintenance immunosuppressive drug, which blocks the CD28 costimulation pathway, preventing the activation of T lymphocytes. To identify the cause of TMA, we ruled out HUS, hepatitis C serology, HIV serology, parvovirus B19, cytomegalovirus, anti-HLA antibodies, and prolonged activated partial thromboplastin time. We suspect that the TMA was caused by the calcineurin inhibitors or proliferation signal inhibitors. Belatacept treatment was initiated at a dose of 10 mg/kg on days 1, 5, 14, 28, 60, and 90; maintenance treatment was 5 mg/kg once a month for 1 year. Belatacept, in combination with other agents, prevented graft rejection in three patients.

Use of bortezomib to treat anti-HLA antibodies in renal transplant patients: A single-center experience

Donor-specific human leukocyte antigen (HLA) antibodies (DSA) are associated with decreased graft survival and may cause graft rejection. Bortezomib, a selective inhibitor of the 26S proteasome developed to treat multiple myeloma, has been used for its anti-plasma cell activity in patients undergoing transplantation. We describe our experience with bortezomib used to reduce anti-HLA antibodies in eight renal transplant patients. Patients received bortezomib (1.3mg/m(2)) on days 1, 4, 8, and 11 beginning when antibodies were detected. It was used alone in one patient and was complemented with plasmapheresis in five patients, with IVIG in one patient, and with IVIG and plasmapheresis in another patient. De novo DSA class II were detected in all eight patients and two also had DSA class I. Antibodies were entirely eliminated in five (62.5%) patients 90 days after treatment but only reduced in the other three (62.5%). Notably, they later increased in one patient. Five (62.5%) patients had AMR, two (25%) had mixed rejection, and one had no rejection. our results suggest that bortezomib is effective for reducing DSA avoiding chronic graft injury.

Critical care providers’ opinion on unsafe abortion in Argentina

To survey the opinion of critical care providers in Argentina about abortion.

Use of kidneys from trypanosoma cruzi-infected donors in naive transplant recipients without prophylactic therapy: the experience in a high-risk area.

Barr-associated leiomyomatosis and T-cell chimerism after haploidentical bone marrow transplantation for severe combined immunodeficiency disease. J Pediatr Hematol Oncol 2007; 29: 166. 5. Monforte-Munoz H, Kapoor N, Saavedra JA. Epstein-Barr virus-associated leiomyomatosis and posttransplant lymphoproliferative disorder in a child with severe combined immunodeficiency: case report and review of the literature. Pediatr Dev Pathol 2003; 6: 449 6. Ibebuike KE, Pather S, Emereole O, et al. Epstein-Barr virus-associated smooth muscle tumour presenting as a parasagittal brain tumour. J Clin Neurosci. 2012; 19: 1589. 7. Suankratay C, Shuangshoti S, Mutirangura A, et al. Epstein-Barr virus infection-associated smooth-muscle tumors in patients with AIDS. Clin Infect Dis 2005; 40: 1521. 8. Borza CM, Hutt-Fletcher LM. Alternate replication in B cells and epithelial cells switches tropism of Epstein-Barr virus. Nat Med 2002; 8: 594. 9. Ong KW, Teo M, Lee V, et al. Expression of EBV latent antigens, mammalian target of rapamycin, and tumor suppression genes in EBV-positive smooth muscle tumors: clinical and therapeutic implications. Clin Cancer Res 2009; 15: 5350. 10. Shen Q, Feng W, Long MS, et al. Multicentric hepatic EBV-associated smooth muscle tumors in an AIDS patient: a case report, investigation of mTOR activation and review of the literature. Int J Clin Exp Pathol 2011; 4: 421.

Amelioration of renal damage by administration of anti-thymocyte globulin to potential donors in a brain death rat model

Brain death (BD), a non‐immunological factor of renal injury, triggers an inflammatory process causing pathological signs of cell death in the kidney, such as necrosis and apoptosis. Kidneys from brain dead donors show lower success rates than kidneys from living donors and one strategy to improve transplantation outcome is to precondition the donors. For the first time, anti‐rat thymoglobulin (rATG) was administered in an experimental brain death animal model to evaluate if it could ameliorate histopathological damage and improve organ function. Animals were divided into three groups: V (n = 5) ventilated for 2 h; BD (n = 5) brain death and ventilated for 2 h; and BD+rATG (n = 5) brain death, ventilated for 2 h, rATG was administered during brain death (10 mg/kg). We observed lower creatinine levels in treatment groups (means): V, 0·88 ± 0·22 mg/dl; BD, 1·37 ± 0·07 mg/dl; and BD+rATG, 0·64 ± 0·02 mg/dl (BD versus BD+rATG, P < 0·001). In the BD group there appeared to be a marked increase of ATN, whereas ATN was decreased significantly in the rATG group (V, 2·25 ± 0·5 versus BD, 4·75 ± 0·5, P < 0·01; BD+rATG, 2·75 ± 0·5 versus BD 4·75 ± 0·5 P < 0·01). Gene expression was evaluated with reverse transcription–polymerase chain reaction; tumour necrosis factor (TNF)‐α, interleukin (IL)‐6, C3, CD86 showed no significant difference between groups. Increased IL‐10 and decreased CCL2 in BD+rATG compared to BD (both cases P < 0·01). Myeloperoxidase was increased significantly after the brain death setting (V: 32 ± 7·5 versus BD: 129 ± 18). Findings suggest that rATG administered to potential donors may ameliorate renal damage caused by BD. These findings could contribute in the search for specific cytoprotective interventions to improve the quality and viability of transplanted organs.

Health insurance status and outcomes of critically ill obstetric patients: A prospective cohort study in Argentina

PURPOSE In Argentina, uninsured patients receive public health care, and the insured receive private health care. Our aim was to compare different outcomes between critically ill obstetric patients from both sectors. METHODS This is a prospective cohort, including pregnant/postpartum patients requiring admission to 1 intensive care unit in the public sector (uninsured) and 1 in the private (insured) from January 1, 2008, to September 30, 2011. RESULTS A total of 151 patients were included in the study. In uninsured (n = 63) vs insured (n = 88) patients, Acute Physiology and Chronic Evaluation II (APACHE II) and Sequential Organ Failure Assessment scores were 11 ± 6.5 vs 8 ± 4 and 3 (2-7) vs 1 (0-2), respectively, and 84% vs 100% received prenatal care (P = .001 for all). Multiple organ dysfunction syndrome (MODS) was present in 32 (54%) uninsured vs 9 (10%) insured patients (P = .001), and acute respiratory distress syndrome developed in 18 (30.5%) of 59 vs 2(2%) of 88 (P = .001). Neonatal survival was 80% vs 96% (P = .003). Variables independently associated with the development of MODS were APACHE II (odds ratio, 1.30 [1.13-1.49]), referral from another hospital (odds ratio, 11.43 [1.86-70.20]), lack of health insurance (odds ratio 6.75 [2.17-20.09]), and shock (odds ratio 4.82 [1.54-15.06]). Three patients died, all uninsured. CONCLUSIONS Uninsured critically ill obstetric patients (public sector) were more severely ill on admission and experienced worse outcomes than insured patients (private sector). Variables independently associated with MODS were APACHE II, shock, referral from another hospital, and lack of insurance.

Evaluation of histological damage of solid organs after donor preconditioning with thymoglobulin in an experimental rat model.

Rabbit anti-rat thymoglobulin (rATG) administered to donors with brain death (BD) may improve organs quality. We explored the effects of rATG administered to BD donors in the histology of heart, lungs and small bowel in a rat experimental model. Animals were randomly assigned to 3 groups: V (n=5) no BD, 2h ventilation; BD (n=5) BD and 2h ventilation; BD and rATG: BD, 2h ventilation, rATG (10mg/kg) after BD diagnosis. Histopathological damage scores were based on neutrophil infiltration, airway epithelial cell damage, interstitial edema, hyaline membrane formation, and pulmonary hemorrhage (lungs); neutrophil infiltration and interstitial edema (heart); Park score (bowel). Lung damage was significantly lower in BD+rATG group: V 5 ± 1.6; BD 11.25 ± 0.5, BD+rATG 6.5 ± 1.9 (p<0.01). Heart: V 2.0 ± 0.81; BD 4.75 ± 1.25 and BD+rATG 3.5 ± 1.7 (p>0.05). Small bowel: BD 2.25 ± 0.96 vs. BD+rATG 1.00 ± 1.15 (n.s.). Histological damage amelioration in lung and attenuation tendency in heart and small bowel encourages research of cytoprotective strategies to improve organ viability.

Recurrent Psoriasis After Introduction of Belatacept in 2 Kidney Transplant Recipients

Organ transplant recipients may have skin diseases as a result of immunosuppression, but psoriasis is reported infrequently. This skin condition may be induced by immunosuppression imbalance. We present 2 cases of recurrent psoriasis in 2 kidney transplant patients with belatacept-based immunosuppressive regimens. Two years after transplant, upon suspicion of calcineurin inhibitor neurotoxicity in the first patient, tacrolimus was replaced with belatacept. The patient’s neurological signs resolved but the patient presented with skin lesions compatible with psoriatic plaques, successfully treated with betamethasone dipropionate and hydrocortisone. The second patient had a history of obesity and dyslipidemia, left foot amputation, and psoriasis. He received a kidney transplant, and maintenance immunosuppression included prednisone, mycophenolate mofetil, and belatacept. At posttransplant month 15, the patient presented with cutaneous erythematosus, maculopapular, and desquamative lesions compatible with psoriasis, treated with betamethasone dipropionate. The belatacept-based immunosuppressive regimens were maintained and psoriasis resolved. Psoriasis is a potential complication in kidney recipients that may recur when belatacept is used and/or tacrolimus is withdrawn as it could have happened in the first patient. The characteristics of the second case may suggest that belatacept might not have been the inciting agent. Good results were obtained with topical treatment.