Dynamics of cell‐mediated immune responses to cytomegalovirus in pediatric transplantation recipients

Patel M, Stefanidou M, Long CB, Fazzari MJ, Tesfa L, Del Rio M, Lamour J, Ricafort R, Madan RP, Herold BC. Dynamics of cell‐mediated immune responses to cytomegalovirus in pediatric transplantation recipients.
Pediatr Transplantation 2012: 16: 18–28. © 2011 John Wiley & Sons A/S. Abstract: CMI responses, combined with quantification of CMV DNA (DNAemia), may identify transplantation recipients at risk for invasive disease. PBMC were collected in pediatric transplantation candidates at one, three, and six months post‐transplant in 10 subjects (six renal, three cardiac, one stem cell) and at single time points in eight HC and 14 children greater than one yr post‐transplant (LTTx). Cells were stimulated with anti‐CD3mAb or CMV pp65 peptide pools and responses assessed by IFNG enzyme‐linked immunosorbent spot assay and cytokine secretion. IFNG responses to anti‐CD3mAb were significantly lower pretransplant relative to HC and were further decreased at one and three months post‐transplant, but recovered to levels comparable to HC by six months. Responses to pp65 among CMV‐seropositive recipients followed a similar pattern but recovered by three months. CMV‐seropositive LTTx and HC showed a Th1 cytokine response to pp65 stimulation. Three LTTx subjects developed CMV DNAemia; two demonstrated decreased responses to anti‐CD3mAB (and pp65 in the CMV seropositive subject) at the onset of DNAemia, which recovered as DNAemia resolved. Monitoring CMI in children is feasible and may provide an adjunct biomarker to predict CMV progression and recovery.     

Fatal graft‐versus‐host disease after living‐donor liver transplantation from an HLA‐DR‐mismatched donor

Acute GVHD is a rare complication after liver transplantation that has a high mortality rate. We experienced an infant case complicated with acute GVHD. An 8‐month‐old infant with biliary atresia underwent LDLT with a graft obtained from his mother. Their HLAs showed a donor‐dominant one‐way match, not at HLA‐DR but at HLA‐A, HLA‐B, and HLA‐C (recipient; A 31/33, B 51/54, C 1/14, DR 9/11, donor; A 31/‐, B 51/‐, C 14/‐, DR 8/11). The patient exhibited a high fever, skin rash, and diarrhea, and was diagnosed with acute GVHD based on the blood chimerism test. Despite immunosuppression treatment with prednisolone and tacrolimus, plasma exchange, blood transfusion including cord blood transplantation, and antibiotics, the child died on postoperative day 126. Donor‐dominant one‐way matching at HLA class 1 can be a high‐risk factor for acute GVHD despite HLA class 2 mismatching.     

Chemotherapy‐induced B‐cell depletion in hepatoblastoma patients undergoing ABO‐incompatible living donor liver transplantation

LT from ABO‐I donors requires preconditioning regimens to prevent postoperative catastrophic AMR. NAC for HBL is known to cause myelosuppression leading to a reduction in the number and function of lymphocytes. We investigated this chemotherapy‐induced myelosuppression in HBL patients listed for LT from ABO‐I donors with reference to the kinetics of B, T cells, and anti‐ABO blood type isoagglutinin titers. Between 2005 and 2015, of the 319 patients who underwent LDLT at our institute, 12 were indicated for unresectable HBL. Three patients with unresectable HBL who underwent LDLT from ABO‐I donors are included in this study. Immunosuppression consisted of a standard regime of tacrolimus and low‐dose steroids as in ABO compatible/identical LDLT. No additional preoperative therapies for B‐cell depletion were used. Absolute lymphocyte counts, lymphocyte subsets (including CD20+ B cells, CD3+CD4+ T cells and CD3+CD8+ T cells), and anti‐ABO blood type isoagglutinin titers were measured before LDLT and postoperatively. The median age at diagnosis was 19 months (range, 3–31 months). The median follow‐up was seven months (range, 6–15 months). The median interval from the last NAC to LDLT was 33 days (range, 25–52 days). The median interval from LDLT to adjuvant chemotherapy was 28 days (range, 22–36 days). The counts of CD20+ B cells before LDLT were depleted to median 5 cells/mm³ (range, 0–6 cells/mm³). There was a transient rebound in the CD20+ B cell counts on day seven (maximum of 82 cells/mm³) followed by a decline starting at 14 days after LDLT that was sustained for the duration of adjuvant chemotherapy. Anti‐ABO blood type isoagglutinin titers were lowered to between 1:1 and 1:16 before LDLT and remained low for the duration of follow‐up in this study. All of the three patients remained in good health without either acute cellular or AMR after LDLT. The B‐cell depletion that occurs after cisplatin‐based chemotherapy for HBL may help accomplish safe ABO‐I LDLT in children without the use of additional conditioning regimens for prevention of AMR.     

Control of graft‐versus‐host disease with rabbit anti‐thymocyte globulin,rituximab, and bortezomib in TCRαβ/CD19‐depleted graft transplantation for leukemia in children: a single‐center retrospective analysis of two GVHD‐prophylaxis regimens

Both acute GVHD and chronic GVHD remain the leading cause of morbidity and death after allogeneic HSCT. We conducted a retrospective analysis comparing two GVHD‐prophylaxis regimens: 35 patients received “Regimen 1” (horse ATG, tacrolimus, and methotrexate) and 46 “Regimen 2” (rabbit ATG, rituximab, and peritransplant bortezomib). All 81 patients with a median age of 9 (0.6‐23) years with ALL (n = 31) or AML (n = 50) in complete remission received TCRαβ/CD19‐depleted transplants between May 2012 and October 2016, from 40 HLA‐matched unrelated and 41 haploidentical donors. After a median follow‐up of 3.9 years, the CI of acute GVHD II‐IV was 15% (95% CI: 7‐30) in the “Regimen 2” group and 34% (95% CI: ?54) in the “Regimen 1” group, P = .05. “Regimen 2” was also more effective in the prevention of chronic GVHD; the CI at 1 year after HSCT was 7% (95% CI: 2‐19) vs 31% (95% CI: 19‐51), P = .005. The CI of relapse at 3 years adjusted for the GVHD‐prophylaxis regimen groups 31% (95% CI: 19‐51) for the “Regimen 1” vs 21% (95% CI: 11‐37) for the “Regimen 2”, P = .3. The retrospective observation suggests that the use of the rATG, rituximab, and bortezomib was associated with significantly lower rate of GVHD without the loss of anti‐leukemic activity.     

Plasmapheresis treatment of antibody‐mediated rejection in an A2 donor to O pediatric liver transplant recipient

Martin T, Schwartz J, Demetris A, Comstock J, Lowichik A, Book L. Plasmapheresis treatment of antibody‐mediated rejection in an A2 donor to O pediatric liver transplant recipient.
Pediatr Transplantation 2011: 15:E15–E18. © 2009 John Wiley & Sons A/S. Abstract: It is safe to transplant kidneys from blood group A2 donors into O recipients if the latter have low titers of anti‐A antibodies. However, in liver transplantation, O and B recipients of A2 donor livers are not routinely screened for anti‐blood group antibodies because of the immuno‐absorptive capacity of the liver and the low incidence of antibody‐mediated rejection. Herein, we report a rare case of combined cell and antibody‐mediated rejection in a pediatric blood group O recipient of an A2 donor liver, and rescue of the allograft using PP and IVIG.     

Successful treatment with pulse cyclophosphamide of a steroid-refractory hepatitic variant of liver acute graft-vs.-host disease in a child

Kawahara Y, Morimoto A, Masuzawa A, Ikeda T, Hayase T, Kashii Y, Nozaki Y, Kanai N, Momoi MY. Successful treatment with pulse cyclophosphamide of a steroid‐refractory hepatitic variant of liver acute graft‐vs.‐host disease in a child.
Pediatr Transplantation 2012: 00: 000–000. © 2012 John Wiley & Sons A/S. Abstract: A 13‐yr‐old boy with recurrent acute myeloid leukemia underwent HSCT using cells from an unrelated donor who matched all HLA antigens except one. Forty‐two days later, the patient developed a steroid‐refractory hepatitic variant of liver GVHD with peak ALT and T.Bil values of 1406 mU/mL and 10.4 mg/dL, respectively. He was successfully treated with pulse Cy (1000 mg/dose × one day) without a change in chimerism being observed or acquiring an infection. All immunosuppressant therapies could be discontinued 12 months after HSCT. Two yr after HSCT, the patient remains in CR without chronic GVHD. This single case report suggests that pulse Cy may be a promising therapy for steroid‐refractory GVHD, especially hepatitic GVHD, but needs to be further tested in clinical trials.     

Glucocorticoids enhance interleukin‐4 production to neo‐antigen (hyaluronidase) in children immunocompromised with cytostatic drugs

Immunoglobulin E (IgE)‐mediated immediate‐type allergic reactions to hyaluronidase have been observed in children with central nervous system (CNS) tumors. Glucocorticoids, used as therapy for brain edema, are discussed controversially as T helper 2 (Th2) stimulatory factors. In this study we investigated the role of glucocorticoids on a Th2 cytokine‐promoting effect in children with CNS tumors. Peripheral blood mononuclear cells (PBMCs) from: 29 children suffering from malignant brain tumors, of whom 23 received short‐term glucocorticoid treatment (for 3–4 days) during the course of chemotherapy; 18 children with nephrotic syndrome or renal transplantation receiving long‐term glucocorticoid treatment; and 13 healthy children, were incubated with phytohemagglutinin (PHA) and/or anti‐CD28 monoclonal antibody (mAb) and, in a second approach, with hyaluronidase. The concentrations of Th cell‐mediated cytokines – interleukin (IL)‐4, IL‐10, and interferon‐γ (IFN‐γ) – were measured in supernatants. The IL‐4 production of PBMCs incubated with PHA/anti‐CD28 mAb from children with repeated co‐administration of glucocorticoids, hyaluronidase, and cytostatic drugs (median: 249.9 pg/ml; range: 234.4–261.7) was significantly higher (p < 0.0001) than IL‐4 production of PBMC from children of all the other groups (median: 86.18; range: 16.0–212.5). There was no significant difference in the levels of IL‐10 and IFN‐γ within the groups. PBMCs stimulated only with hyaluronidase failed to produce detectable levels of cytokines. The results of this study indicate that repeated co‐administration of glucocorticoids and hyaluronidase (a neo‐antigen) enhance IL‐4 production in vitro and thus may induce the production of specific IgE antibodies in children immunocompromised with cytostatic drugs. Hyaluronidase itself does not stimulate in vitro IL‐4 synthesis in PBMCs of children receiving cytostatic drugs.     

Hemophagocytosis after bone marrow transplantation for JAK3‐deficient severe combined immunodeficiency

Hashii Y, Yoshida H, Kuroda S, Kusuki S, Sato E, Tokimasa S, Ohta H, Matsubara Y, Kinoshita S, Nakagawa N, Imai K, Nonoyama S, Oshima K, Ohara O, Ozono K. Hemophagocytosis after bone marrow transplantation for JAK3‐deficient severe combined immunodeficiency.
Pediatr Transplantation 2010: 14:E105–E109. © 2009 John Wiley & Sons A/S. Abstract: HSCT is the optimal treatment for patients with SCID. In particular, HSCT from a HLA‐identical donor gives rise to successful engraftment with long survival. We report a six‐month‐old girl with JAK3‐deficient SCID who developed hemophagocytosis after BMT without conditioning from her HLA‐identical father. She had suffered from pneumonia and hepatitis before BMT. Prophylaxis for GVHD was short‐term methotrexate and tacrolimus. On day 18 after BMT, the patient developed hemophagocytosis in bone marrow when donor lymphocytes were increasing in peripheral blood. Analysis of chimerism confirmed host origin of macrophages and donor origin of lymphocytes. Thus, host macrophage activation was presumably induced in response to donor lymphocytes through immunoreaction to infections and/or alloantigens. HSCT for SCID necessitates caution with respect to hemophagocytosis.     

Graft‐versus‐host disease (GVHD) prophylaxis by using methotrexate decreases pre‐engraftment syndrome and severe acute GVHD,and accelerates engraftment after cord blood transplantation

GVHD and graft failure are serious problems in CBT. PES after CBT also occurs frequently and is associated with transplantation‐related complications such as acute GVHD. We reviewed medical records for 70 consecutive child CBT recipients between December 1997 and April 2015. Forty‐nine patients received prophylaxis against GVHD with CsA or Tac in combination with mPSL from day +7 (mPSL group), and 21 patients received CsA or Tac with MTX on day +1 and day +3 (MTX group). Neutrophil engraftment was detected in 59 patients (84.3%). Neutrophil engraftment rate in the MTX group was significantly higher than that in the mPSL group (21/21 (100%) and 38/49 (77.6%), respectively, p = 0.027). PES developed in 35 patients, and the incidence of PES in the mPSL group was significantly higher than that in the MTX group (p = 0.036). The incidence of severe acute GVHD (grade III or IV) in the MTX group was significantly lower than that in the mPSL group (p = 0.049). Although this study was a small‐scale study, the results showed that increase in the rate of engraftment and decrease in the incidence of early immune reactions such as PES and severe acute GVHD could be achieved by early commencement of immunosuppression using MTX.     

Facilitating cells as a venue to establish mixed chimerism and tolerance

Graft rejection and the toxicity associated with the use of non-specific immunosuppression remain the major limitations in pediatric solid organ transplantation. The induction of tolerance in transplant recipients is an elusive but achievable goal that will decrease the dependence on immunosuppressive agents. BMT is associated with a robust form of donor-specific transplantation tolerance. It achieves a state of chimerism, defined as the presence of donor marrow cells in the recipient. The two major toxicities in conventional bone marrow transplantation that have prevented its clinical application to induce tolerance are the toxicity of ablative conditioning and GVHD. Two forms of chimerism exist: full chimerism and mixed chimerism. In full chimerism, the hematopoietic system of the recipient is replaced by that of the donor following ablative conditioning. Full chimerism is associated with a relatively impaired immunocompetence for primary immune responses and an increased risk of GVHD. In addition, the 7-10% regimen-related mortality associated with ablation could not be accepted in solid organ allograft recipients. In mixed chimerism the donor hematopoietic system co-exists with that of the recipient. Mixed chimerism induces donor-specific tolerance and is associated with superior immunocompetence and a relative resistance to GVHD compared with full chimerism. Moreover, it can be achieved with partial conditioning, thereby reducing the regimen-related morbidity associated with myeloablation. Approaches to establish mixed chimerism using non-myeloablative-conditioning regimens have been aggressively pursued over the past decade. Mixed chimerism can be safely established with minimal conditioning, resulting in a significant reduction in risk compared with ablative conditioning. GVHD is the final hurdle that has prevented the widespread application of chimerism to induce tolerance. Donor T cells are the primary effector cells for GVHD. Although T cell depletion of the donor marrow avoids GVHD, it results in an increase in the rate of graft failure in MHC-disparate recipients. The dichotomy between GVHD and T cell depletion graft failure has recently been dissociated by the discovery of CD8+/TCR- graft FC. Purified HSC engraft readily in syngeneic recipients but not in MHC-disparate allogeneic recipients. The addition of small numbers of facilitating cells permits durable HSC engraftment in allogeneic recipients and avoids GVHD. Using FC to promote HSC engraftment following non-myeloablative conditioning could be a promising approach to establish tolerance in solid organ transplantation. This invited review focuses on recent developments in stem cell chimerism and tolerance that could bring the use of this approach to induce tolerance to solid organ transplantation one step closer to reality.     

The use of hepatitis B immunoglobulin with or without hepatitis B vaccine to prevent de novo hepatitis B in pediatric recipients of anti‐HBc–positive livers

Prophylactic measures are used to reduce DNHB after HBsAg‐negative patients receive anti‐HBc–positive liver grafts. This study investigated the incidence of DNHB and clinical outcomes in pediatric LT recipients under HBIG prophylaxis, with or without hepatitis B vaccination. Between 1995 and 2013, 51 HBsAg‐negative pediatric recipients underwent living‐donor LT from anti‐HBc–positive donors. The median (range) age was 4 (0.1‐17) years, 23 (45%) were male, and 71% were negative for both anti‐HBc and anti‐HBc. During a median follow‐up of 12.1 (0.06‐19.9) years, 13 (25.4%) developed DNHB; 7 of the 13 achieved HBsAg seroconversion after administration of LAM or ETV. Among studied patients, 20 (39%) received hepatitis B vaccination, and 2 of them (10%) developed DNHB. At last follow‐up, 41% (21/51) discontinued HBIG either after successful HBV vaccination (n = 17) or retransplantation with anti‐HBc–negative grafts (n = 4). In conclusion, pediatric LT recipients of anti‐HBc–positive grafts, most of them were naïve to HBV infection, were at high risk of DNHB, and consistent monitoring for the early detection of DNHB was necessary. A combination use of post‐LT vaccination is promising prophylactic strategy against DNHB.     

Increased levels of PD‐1 expression on CD8 T cells in patients post‐renal transplant irrespective of chronic high EBV viral load

Studies have identified solid organ transplant recipients who remain asymptomatic despite maintaining CHL. Factors which determine the CHL state remain poorly understood but are likely to involve immunological control of the viral infection. We monitored expression of PD‐1, a marker of T‐cell exhaustion and viral persistence, on CD8 T cells in patients who resolved EBV infection as determined by undetectable EBV DNA (REI) and CHL patients. PD‐1 expression on CD8 T cells was increased in the first year post‐transplant irrespective of EBV outcome, and most CD8 T cells continued to express PD‐1 for up to three yr post‐transplant. Although all patient groups showed similar frequencies of EBV‐specific CD8+ T cells, PD‐1 expression on these cells increased in the post‐transplant groups compared with the pretransplant patients. Functional studies of EBV‐specific CD8+ T cells stimulated with BZLF or LMP2 peptide pools revealed monofunctional IFN‐γ responses. Our results indicate that PD‐1 expression on CD8 T cells post‐transplant may result from factors other than antigenic stimulation.     

Evidence for BCR/ABL1‐positive T‐cell acute lymphoblastic leukemia arising in an early lymphoid progenitor cell

BCR‐ABL1‐positive leukemias have historically been classified as either chronic myelogenous leukemia or Ph+ acute lymphoblastic leukemia. Recent analyses suggest there may be a wider range of subtypes. We report a patient with BCR‐ABL1 fusion positive T‐cell ALL with a previously undescribed cell distribution of the fusion gene. The examination of sorted cells by fluorescence in situ hybridization showed the BCR‐ABL1 fusion in the malignant T cells and a subpopulation of the nonmalignant B cells, but not nonmalignant T cells or myeloid or CD34+ progenitor cells providing evidence that the fusion may have occurred in an early lymphoid progenitor.     

Successful haploidentical PBSCT with subsequent T‐cell addbacks in a boy with HyperIgM syndrome presenting as severe congenital neutropenia

Jasinska A, Kalwak K, Trelinska J, Borowiec M, Piatosa B, Zeman K, Mlynarski W. Successful haploidentical PBSCT with subsequent T‐cell addbacks in a boy with HyperIgM syndrome presenting as severe congenital neutropenia. Abstract: HIGM syndrome is a group of primary immunodeficiency disorders characterized by recurrent bacterial and opportunistic infections; it is also associated with normal to elevated serum IgM levels and a concomitant deficiency of IgG, IgA, and IgE. In this report, we give account of a boy with X‐linked HIGM and a novel Y172C mutation within his CD40LG gene. He presented with severe neutropenia as the dominating symptom. His bone marrow showed maturation arrest at the promyelocyte/myelocyte stage, typical of congenital neutropenia. This boy suffered from life‐threatening infections and required high doses of rhG‐CSF, and a haploidentical PBSCT was also successfully performed, thus leading to reconstitution of CD40L expression on activated CD4+ T cells (as assessed with flow cytometry six months after the procedure). Two low‐dose T‐cell addbacks were required to re‐establish full donor chimerism and clear CMV reactivation. The report demonstrates that in select cases, alternative donor allogeneic HSCT supported by DLI may be effective in correcting the defect in X‐linked HIGM, and HSCT in HIGM children is not necessarily limited to matched sibling donor transplantation.     

Living related liver transplant following bone marrow transplantation from same donor: Long‐term survival without immunosuppression

Granot E, Loewenthal R, Jakobovich E, Gazit E, Sokal E, Reding R. Living related liver transplant following bone marrow transplantation from same donor: Long‐term survival without immunosuppression.
Pediatr Transplantation 2012: 16: E1–E4. © 2010 John Wiley & Sons A/S. Abstract: We report long‐term (seven yr) immunological tolerance in a 16‐yr‐old boy, to a liver allograft donated by his father following a bone marrow transplant at age 2.5 yr from the same donor. The bone marrow transplant was complicated by severe GVHD leading to liver failure and the ensuing need for a liver transplant, performed under planned avoidance of immunosuppression. At one wk post‐transplant, although a liver biopsy was histologically compatible with acute rejection, favorable clinical and biochemical evolution precluded initiating immunosuppressive therapy, thus highlighting the need for caution when interpreting early histological changes so that administration of unnecessary immunosuppression can be avoided. Induction of tolerance in transplant recipients remains an elusive goal. In those patients who had received conventional bone marrow transplants and had endured the consequences of GVHD, development of macrochimerism may allow immunosuppression‐free solid organ transplantation from the same donor.     

CD154‐expressing CMV‐specific T cells associate with freedom from DNAemia and may be protective in seronegative recipients after liver or intestine transplantation

Cell‐mediated immunity to CMV, if known, could improve antiviral drug therapy in at‐risk children and young adults with LT and IT. Host immunity has been measured with CMV‐specific T cells, which express IFNγ, but not those which express CD154, a possible substitute for IFNγ. CMV‐specific CD154+ T cells and their subsets were measured with flow cytometry after stimulating PBL from recipient blood samples with an overlapping peptide mix of CMV‐pp65 antigen for up to 6 hours. CMV‐specific CD154+ T cells co‐expressed IFNγ in PBL from three healthy adults and averaged 3.8% (95% CI 3.2%‐4.4%) in 40 healthy adults. CMV‐specific T cells were significantly lower in 19 CMV DNAemic LT or IT recipients, compared with 126 non‐DNAemic recipients, 1.3% (95% CI 0.8‐1.7) vs 4.1 (95% CI 3.6‐4.6, P < .001). All T‐cell subsets demonstrated similar between‐group differences. In logistic regression analysis of 46 training set samples, 12 with DNAemia, all obtained between days 0 and 60 from transplant, CMV‐specific T‐cell frequencies ≥1.7% predicted freedom from DNAemia with NPV of 93%. Sensitivity, specificity, and PPV were 83%, 74%, and 53%, respectively. Test performance was replicated in 99 validation samples. In 32 of 46 training set samples, all from seronegative recipients, one of 19 recipients with CMV‐specific T‐cell frequencies ≥1.7% experienced DNAemia, compared with 8 of 13 recipients with frequencies <1.7% (P = .001). CMV‐specific CD154+ T cells are associated with freedom from DNAemia after LT and IT. Among seronegative recipients, CMV‐specific T cells may protect against the development of CMV DNAemia.     

Selective expansion of donor‐derived regulatory T cells after allogeneic bone marrow transplantation in a patient with IPEX syndrome

IPEX syndrome is a rare and fatal disorder caused by absence of regulatory T cells (Tregs) due to congenital mutations in the Forkhead box protein 3 gene. Here, we report a patient with IPEX syndrome treated with RIC followed by allogeneic BMT from an HLA‐matched sibling donor. We could achieve engraftment and regimen‐related toxicity was well tolerated. Although the patient was in mixed chimera and the ratio of donor cells in whole peripheral blood remained relatively low, selective and sustained expansion of Tregs determined as CD4+CD25+Foxp3+ cells was observed. Improvement in clinical symptoms was correlated with expansion of donor‐derived Tregs and disappearance of anti‐villin autoantibody, which was involved in the pathogenesis of gastrointestinal symptoms in IPEX syndrome. This clinical observation suggests that donor‐derived Tregs have selective growth advantage in patients with IPEX syndrome even in mixed chimera after allogeneic BMT and contribute to the control of clinical symptoms caused by the defect of Tregs.     

Alemtuzumab with corticosteroid minimization for pediatric deceased donor renal transplantation: A seven‐yr experience

Alemtuzumab is a monoclonal antibody targeting CD52 receptors on B and T lymphocytes and is an effective induction agent in pediatric renal transplantation. We report a seven‐yr experience using alemtuzumab induction and steroid‐free protocol in the pediatric population as safe and effective. Twenty‐one pediatric deceased donor renal transplants were performed at a single academic institution. All received induction with single‐dose alemtuzumab and were maintained on a steroid‐free protocol using TAC and MMF immunosuppression. There were 15 males and six females in the study whose ages ranged from one to 19 yr. The average follow‐up was 32 months (range from 12 to 78.2 months and median 33.7 ± 23.7 months). All patients had immediate graft function. Graft survival was 95%, and patient survival was 100%. Mean 12 and 36 months eGFR were 63.33 ± 21.01 and 59.90 ± 15.27 mL/min/1.73m², respectively. Three patients developed acute T‐cell‐mediated rejection due to non‐adherence while no recipients developed cytomegalovirus infection, PTLD, or polyoma BK viral nephropathy. Steroid avoidance with single‐dose alemtuzumab induction provides adequate and safe immunosuppression in pediatric deceased donor renal transplant recipients receiving TAC and low‐dose MMF maintenance therapy.     

Hematopoietic stem cell transplant for hyper‐IgM syndrome due to CD40L defects: A single‐center experience

HIGMI is a disease with a high risk for morbidity and mortality. HSCT has been shown to be a curative option. This study retrospectively reviewed and analyzed data from five patients who received HSCT at King Faisal Specialist Hospital & Research Centre (KFSH&RC) in Riyadh, Saudi Arabia, between 2005 and 2013. Five patients with HIGMI syndrome underwent HSCT at a median age of 41 months (range, 9–72 months). The median time from diagnosis to transplantation was 30 months (range, 5–58 months). For all five patients, the donors were HLA‐identical siblings. In three patients, the conditioning regimen was composed of BU and CY. Fludarabine and melphalan with either ATG or alemtuzumab was used in two patients. For GVHD prophylaxis, cyclosporine was used in two patients, and the combination of cyclosporine and MTX was used in three patients. The survival rate was 100%, with a median follow‐up of 69 months (range, 13–100 months). All patients engrafted. Two patients developed acute GVHD. Four patients showed complete immune recovery with positive CD40L expression in activated T cells and discontinued IVIG replacement. HSCT in early stage from an HLA‐matched sibling donor is potentially effective at curing the disease.