Antilymphocyte globulin (ALG) was given every other day for 5 doses with platelet transfusions immediately following ALG administration in 6 patients with aplastic anaemia. Four patients responded and 3 durable remissions were achieved. One patient relapsed and further treatment with anti-thymocyte globulin and cyclosporin also failed. One patient died of Flavobacterium septicaemia 6 days after completion of ALG. Our data suggests that using an alternate day regimen, a response rate similar to a daily regimen can be obtained.
Due to the unavailability of horse antithymocyte globulin (ATG) in many markets worldwide, patients with severe aplastic anemia (SAA) are limited to the use of rabbit ATG. We aimed to analyze hematologic response and overall survival (OS) of Asian patients treated with rabbit ATG as first-line therapy of SAA. We retrospectively reviewed the medical records of 97 consecutive patients who received rabbit ATG as first-line treatment of SAA from 2006 to 2012 at centers in four Asian countries. The primary endpoint was 6- and 12-month overall response rates (ORR) for patients receiving rabbit ATG within the recommended dose range (2.5-3.75 mg/kg/day). Secondary endpoints included ORR in patients receiving any dose of rabbit ATG and 2-year OS. For patients who received rabbit ATG within the recommended dose range, 6- and 12-month ORRs were 17.4 and 63.6 %, respectively. For patients who received any dose of rabbit ATG, 6- and 12-month ORRs were 24.3 and 68.6 %, respectively. The 2-year OS rate was 86.3 %. Rabbit ATG is effective for treatment of SAA in Asian patients. The 12-month ORR and 2-year OS with rabbit ATG were comparable to historical results obtained with horse ATG.
Antibody-mediated rejection (AMR) still persists as the major hurdle towards successful renal allograft survival. This paper aims to report on the HLA antibody landscape of renal transplant candidates in Malaysia. A total of 2,219 adult samples from 2016 to 2019 were analysed for anti-HLA antibodies using solid-phase assay. Our findings highlight the prevalence and risk factors for antibodies against HLA antigens in renal transplant settings, which could be beneficial for selecting compatible recipients from deceased organ donors. To the best of our knowledge, this study is the first to demonstrate that ethnic Malay and Chinese showed significantly higher prevalence of anti-HLA antibodies. Based on our multivariate analysis: (i) female gender was associated with higher risk for panel reactive antibodies (PRAs) against Class I, Class II, and Class I and II (p
The aim of induction therapy in the management of kidney transplant is to reduce the incidence of acute rejection and delayed graft function after kidney transplant. The agent for induction therapy differs depending on the recipient risks. The regimen can be either polyclonal (rabbit antithymocyte globulin [rATG]) or monoclonal antibody (basiliximab). Basiliximab is commonly used in patients with low immunologic risk. However, to date we know that the use of rATG on T cell depletion is dose dependent and more potent antirejection therapy. Therefore, we would like to look at 1-year graft function of very low-dose rATG in low immunologic risk recipients. All low immunologic risk patients who received low-dose rATG (0.5 mg/kg of body weight daily) during transplant (day 0) and on days 1 and 2 were recruited. Their renal function, HLA donor-specific antibodies, lymphocyte counts, protocol biopsy results, and cytomegalovirus (CMV) polymerase chain reaction were monitored as per clinical practice. All 10 patients had immediate graft function. Low-dose rATG caused lymphocyte counts to deplete immediately on day 0, and the effect lasted about 1 month post-transplant. All the patients had stable graft function without any significance episode of rejection. Only one patient had de novo HLA-DQ antibody. It is good to know that without prophylaxis antiviral in CMV+ donor to CMV+ recipient, the incidence of CMV viremia is considerably low in our cohort. Very low-dose rATG is an effective induction immunosuppression in low immunologic risk patients with acceptable infection risk.
The shortage of deceased donors led to an increase of living related renal transplant performed in the presence of donor-specific antibodies (DSAs) or ABO incompatibilities. There are various desensitization protocols that have been proposed. Here, we describe the outcome of these sensitized patients. This is a prospective cohort study recruiting all kidney transplant recipients from August 2016 until June 2018. Deceased donations, ABO incompatible patients, and sensitized patients who were not prescribed on our desensitization protocol were excluded. Recipients were screened for the presence of HLA-antibodies 1 month before transplant. Those with positive DSA will undergo flow cytometry (risk stratification). We are using a protocol that consisted of intravenous rituximab 200 mg (day -14), intravenous antithymocyte globulin 5mg/kg (day 0-4), plasma exchange post transplant for patients with mean fluorescent intensity (MFI) < 3000, and negative flow cytometry. Those patients with MFI ≥ 3000 or positive flow cytometry need extra cycles pretransplant. A total of 40 patients were recruited, and 20 were sensitized patients. Among the sensitized group 4 of 20 had flow cytometry crossmatch positive, while all had preformed HLA-DSA. A total of 8 of 20 had class I HLA-DSA, 11 of 20 had class II HLA-DSA, and 1of 20 was positive for both class I and II HLA-DSA. Mean immunodominant MFI was 2133.4 (standard deviation [SD], 4451.24) and 1383.7 (SD, 2979.02) for class I and class II, respectively. At 1 year, mean serum creatinine was 108.90 (SD, 25.95) and 118.42 (SD, 31.68) in sensitized and unsensitized patients, respectively. One of 20 unsensitized patients had Banff 1B rejection at 3 months, and there was no significant rejection in sensitized patients at 6 months and 1 year. There was no difference in the occurrence of de novo HLA-DSA between the groups. Desensitization protocols may help to overcome incompatibility barriers in living donor renal transplant. The combination of low-dose rituximab, antithymocyte globulin, and judicious use of plasma exchange has worked well for our cohort.