Model based ATG in αβhaplo-HSCT facilitates engraftment, expedites T-cell recovery, and mitigates the risk of acute GvHD

BACKGROUND

In αβ T-cell/CD19 B-cell depleted hematopoietic stem cell transplantation (αβhaplo-HSCT) recipients, anti--thymocyte globulin (ATG, Thymoglobulin®) is used for preventing graft rejection and graft-versus-host disease (GvHD). However, optimal dosing has yet to be established. Here, we present the first comparative analysis of three different ATG dosing strategies and their impact on immune reconstitution and GvHD.

OBJECTIVE(S)

Our study aims to evaluate the effects of three distinct dosing strategies of ATG on engraftment success, αβ+ and γδ+ T-cells immune reconstitution, and the incidence and severity of acute GvHD in recipients of αβhaplo-HSCT.

STUDY DESIGN

This comparative analysis includes three cohorts of pediatric patients with malignant (36) or non-malignant diseases (8). Cohorts 1 and 2 were given fixed ATG doses, while cohort 3 received doses via a new nomogram, based on absolute lymphocyte count (ALC) and body weight (BW).

RESULTS

Cohort 3 showed 0% incidence of Day-100 grade II-IV acute GvHD, as opposed to 48% and 27% in cohort 1 and 2, respectively. Further, cohort 3 (the ALC/BW-based cohort) had a significant increase in CD4+ and CD8+ naïve T-cells by Day 90 (P=0.04; P=0.03). Additionally, we found that the reconstitution and maturation of γδ+ T-cells post-HSCT was not impacted across all three cohorts. Cumulative ATG exposure in all cohorts was lower than previously reported in T-cell replete settings, with a lower pre-HSCT exposure (<40 AU*day/mL) correlating with engraftment failure (p=0.007). Conversely, a post-HSCT ATG exposure between 10-15 AU*day/mL was optimal for improving Day-100 CD4+ (p= 0.058) and CD8+ (p=0.03) immune reconstitution, without increasing relapse or non-relapse mortality risks.

CONCLUSION(S)

This study represents the first comparative analysis of ATG Thymoglobulin® exposure in αβhaplo-HSCT recipients. Our findings indicate that i) a 1-2-fold ATG to ATLG bioequivalence is more effective than previously established standards, and ii) ATG exposure post-HSCT does not adversely affect γδ+ T-cell immune reconstitution. Furthermore, a model-based ATG dosing strategy effectively reduces graft rejection and Day-100 acute GvHD while also promoting early CD4+/CD8+ immune reconstitution. These insights suggest that further optimization, including more distal administration of higher ATG doses within an ALC/BW-based strategy, will yield even greater improvements in outcomes.

Evaluation of equine xenogeneic mixed lymphocyte reactions using 5-ethynyl-2'-deoxyuridine (EdU)

Allogeneic solid organ transplantation is currently the only treatment option for end stage organ disease. The shortage of available donor organs has driven efforts to utilize xenogeneic organs for transplantation. In vitro methods for evaluating immune-compatibility are a quick and low cost means of screening novel tissue products prior to more involved, expensive, and invasive live animal studies. Recently, a new analog of the DNA base thymidine, 5-ethynyl-2'-deoxyuridine (EdU), was developed. It may be used in a fast, efficient and specific means of evaluating cell proliferation via flow cytometry. This study was designed to test and optimize this platform for assessing equine xenogeneic one-way mixed lymphocyte reaction (MLR) to porcine stimulator cells. Furthermore, it was hypothesized that an enriched T-lymphocyte (T-cell) population would generate a stronger proliferative response to stimulation, and higher levels of cytokine production when compared to unfractionated peripheral blood mononuclear cells (PBMCs). PBMCs and T-cells were isolated from 3 horses and 4 pigs. Equine xenogeneic MLRs were set up using porcine allogeneic MLRs as a reference for clinically acceptable levels of cell proliferation. Equine T-cells showed significantly greater EdU incorporation in one-way xenogeneic MLRs than equine PBMCs. However, there was no significant difference in cell proliferation between porcine T-cell and PBMC as responders in allogenic one-way MLRs. Given the results of this study, we consider that enriched equine T-cells should be used in preference to unfractionated PBMCs when attempting to evaluate the equine xenogeneic response using the EdU assay as an indicator of suitability for transplant in vivo.

Cytokines in Liver Transplantation

Cytokines, soluble mediators of the immune system, play a critical role in the pathogenesis of autoimmune, allergic and infectious diseases. They are also implicated in the initiation and development of allograft rejection. During recent years, there have been considerable advances in generating novel anti-cytokine agents with promoted efficacy and safety, which could be administrated for managing dysregulated cytokine secretion; besides, gene therapy for overexpression of immunomodulatory cytokines has shown substantial improvements. Liver transplantation has been established as a life-saving treatment for end-stage hepatic diseases but the growing number of recipients urge for improved post-transplant care including tolerance induction, infection control and resolving immunosuppressant drugs adverse effects. Cytokines with a wide range of proinflammatory and regulatory properties might be considered as potential therapeutic targets for selective suppression or enhancement of the immune responses in recipients. In the present review, we aimed to summarize the positive and negative effects of cytokines on liver allograft in addition to their prognostic and therapeutic values.

Mycophenolic Acid Trough Concentration and Dose Are Associated with Hematologic Abnormalities but Not Rejection in Kidney Transplant Recipients

BACKGROUND

Little is known regarding the safe fixed dose of mycophenolic acid (MPA) for preventing biopsy-proven acute rejection (BPAR) in kidney transplant recipients (KTRs). We investigated the correlation of MPA trough concentration (MPA C₀) and dose with renal transplant outcomes and adverse events.

METHODS

This study included 79 consecutive KTRs who received MPA with tacrolimus (TAC) and corticosteroids. The MPA C₀ of all the enrolled KTRs was measured, which was determined monthly by using particle-enhanced turbidimetric inhibition immunoassay for 12 months, and clinical data were collected at each time point. The clinical endpoints included BPAR, any cytopenia, and BK or cytomegalovirus infections.

RESULTS

No differences in MPA C₀ and dose were observed between KTRs with or without BPAR or viral infections under statistically comparable TAC concentrations. MPA C₀ was significantly higher in patients with leukopenia (P = 0.021) and anemia (P = 0.002) compared with those without cytopenia. The MPA dose was significantly higher in patients with thrombocytopenia (P = 0.002) compared with those without thrombocytopenia. MPA C₀ ≥ 3.5 μg/mL was an independent risk factor for leukopenia (adjusted odds ratio [AOR], 3.80; 95% confidence interval [CI], 1.24-11.64; P = 0.019) and anemia (AOR, 5.90; 95% CI, 1.27-27.51; P = 0.024). An MPA dose greater than the mean value of 1,188.8 mg/day was an independent risk factor for thrombocytopenia (AOR, 3.83; 95% CI, 1.15-12.78; P = 0.029). However, an MPA dose less than the mean value of 1,137.3 mg/day did not increase the risk of BPAR.

CONCLUSION

Either a higher MPA C₀ or dose is associated with an increased risk of cytopenia, but neither a lower MPA C₀ nor dose is associated with BPAR within the first year of transplantation. Hence, a reduced MPA dose with TAC and corticosteroids might be safe in terms of reducing hematologic abnormalities without causing rejection.

Emphysematous gastritis due to Sarcina ventriculi infection in a diabetic liver-kidney transplant recipient

Emphysematous gastritis (EG) is a rare and potentially lethal process caused by invasive, gas-producing bacteria leading to inflammation and gas dissection of the stomach. The most common etiologic agents are Clostridium infections, but other organisms, including enterobacteria, staphylococcus, and fungi have also been identified. We report the first case of EG due to Sarcina ventriculi in a solid organ transplant recipient, who presented with epigastric pain and vomiting. The patient had a history of type 1 diabetes mellitus (DM) with recurrent episodes of ketoacidosis and systemic diabetic complications, including severe gastroparesis. CT scan studies demonstrated EG with venous air, and endoscopy showed severe gastritis and ulcerations. In the gastric biopsies, abundant Sarcina ventriculi were noted in areas of mucosal/submucosal necrosis. Antibiotic treatment was instituted at admission, and subsequent endoscopy demonstrated the disappearance of Sarcina, with some improvement of the gastric inflammation; however, the patient developed septic shock with multiorgan failure and expired. This case highlights the need to consider other infectious etiologies in transplant patients, in addition to the well-known opportunistic infections.

Graft Rejection Prediction Following Kidney Transplantation Using Machine Learning Techniques: A Systematic Review and Meta-Analysis

Kidney transplantation is recommended for patients with End-Stage Renal Disease (ESRD). However, complications, such as graft rejection are hard to predict due to donor and recipient variability. This study discusses the role of machine learning (ML) in predicting graft rejection following kidney transplantation, by reviewing the available related literature. PubMed, DBLP, and Scopus databases were searched to identify studies that utilized ML methods, in predicting outcome following kidney transplants. Fourteen studies were included. This study reviewed the deployment of ML in 109,317 kidney transplant patients from 14 studies. We extracted five different ML algorithms from reviewed studies. Decision Tree (DT) algorithms revealed slightly higher performance with overall mean Area Under the Curve (AUC) for DT (79.5% ± 0.06) was higher than Artificial Neural Network (ANN) (78.2% ± 0.08). For predicting graft rejection, ANN and DT were at the top among ML models that had higher accuracy and AUC.

Characteristics and Clinical Significance of De Novo Donor-Specific Anti-HLA Antibodies after Kidney Transplantation

BACKGROUND

The association of de novo donor-specific anti-human leukocyte antigens (HLA) antibodies (DSA) and development of antibody-mediated rejection (AMR) in kidney transplant recipients (KTRs) is still undetermined.

METHODS

We prospectively screened de novo DSA in 167 KTRs during 32 months after kidney transplantation (KT). Timing of DSA detection was at 3, 6, and 12 months post-transplant and annually thereafter and when clinically indicated. DSA levels were determined by Luminex assays and expressed as mean fluorescence intensity (MFI). We evaluated the incidence, characteristics of DSA, and association between DSA and tacrolimus trough levels or AMR.

RESULTS

De novo DSA developed in 16 KTRs (9.6%) and acute AMR occurred more commonly in KTRs with de novo DSA compared to KTRs without de novo DSA (18.8% vs. 0%, P < 0.001). All de novo DSA were against class II antigens. The mean number of DSA was 1.8 ± 1.2 and the average MFI of DSA was 7,399 ± 5,470. Tacrolimus trough level during the first 0-2 months after KT was an independent predictor of DSA development (hazard ratio, 0.70; 95% confidence interval, 0.50-0.99; P = 0.043). No differences were found in the number of DSA, average MFI of DSA, and tacrolimus levels during the first year between de novo DSA-positive KTRs with AMR and those without AMR.

CONCLUSION

The results of our study suggest that monitoring of DSA and maintaining proper tacrolimus levels are essential to prevent AMR during the initial period after KT.

Prediction of Kidney Graft Rejection Using Artificial Neural Network

OBJECTIVES

Kidney transplantation is the best renal replacement therapy for patients with end-stage renal disease. Several studies have attempted to identify predisposing factors of graft rejection; however, the results have been inconsistent. We aimed to identify prognostic factors associated with kidney transplant rejection using the artificial neural network (ANN) approach and to compare the results with those obtained by logistic regression (LR).

METHODS

The study used information regarding 378 patients who had undergone kidney transplantation from a retrospective study conducted in Hamadan, Western Iran, from 1994 to 2011. ANN was used to identify potential important risk factors for chronic nonreversible graft rejection.

RESULTS

Recipients' age, creatinine level, cold ischemic time, and hemoglobin level at discharge were identified as the most important prognostic factors by ANN. The ANN model showed higher total accuracy (0.75 vs. 0.55 for LR), and the area under the ROC curve (0.88 vs. 0.75 for LR) was better than that obtained with LR.

CONCLUSIONS

The results of this study indicate that the ANN model outperformed LR in the prediction of kidney transplantation failure. Therefore, this approach is a promising classifier for predicting graft failure to improve patients' survival and quality of life, and it should be further investigated for the prediction of other clinical outcomes.

[Blood group incompatibility as risk of corneal rejection]

BACKGROUND

There is a high risk of rejection of a corneal transplant known as a “rejection episode” in our Hospital conditioned by multiple variables. The aim of this article is to analyze the different risk factors of “corneal rejection episode” in post-transplant patients at one year of follow-up and in particular to consider the presence of donor blood incompatibility during the first year of post-surgical follow-up.

METHODS

A nested case-control study was designed in a cohort: observational, longitudinal, analytical and retrospective from year 2012 to 2013. We performed OR and logistic regression of the variables that influenced rejection.

RESULTS

We included 101 consecutive transplants from multiorgan donation. The variables that influenced the rejection episode were: preoperative high risk group, graft size, blood incompatibility, female gender and age over 60 years old. Other variables such as the presence of comorbidities, combined surgery, surgical time greater than one hour and postoperative complications did not show significant differences.

CONCLUSIONS

It is advisable to perform routine blood compatibility to reduce the risk of rejection.

Systemic Immunomodulatory Strategies in High-risk Corneal Transplantation

The cornea is the most commonly transplanted tissue in the body. Although corneal grafts generally have high success rates, transplantation onto inflamed and vascularized host beds, or so-called high-risk corneal transplantation, has a high rate of graft rejection. The management of this high-risk corneal transplantation is challenging and involves numerous measures. One of the key measures to prevent graft rejection in these cases is the use of systemic immunosuppressive agents. In this article, we will review the systemic immunosuppressive agents most commonly used for high-risk corneal transplantation, which include corticosteroids, cysclosporine A, tacrolimus, mycophenolate mofetil, and rapamycin. Benefits, risks, and published data on the use of these medications for high-risk corneal transplantation will be detailed. We will also summarize novel immunoregulatory approaches that may be used to prevent graft rejection in high-risk corneal transplantation.

Lymphocyte Activation Markers in Pediatric Kidney Transplant Recipients

BACKGROUND AND OBJECTIVES

The role of CD4+CD25+ T regulatory cells (Tregs) in immune tolerance in experimental transplantation is very important but the clinical significance of circulating Tregs in the peripheral blood is undetermined. We evaluated the association between the frequency of T cell activation markers CD25 and CD71 and clinical parameters that may affect the level of these T cell markers.

METHODS

In 47peditric kidney transplant (KT) recipients and 20 healthy controls, the frequency of T cell activation markers, CD25 and CD71 was measured with flow cytometry after transplantation. Two clinical protocols of induction immunosuppression were used: (1) anti-thymocyte globulin (THYMO) group (n =29) and Basiliximab (BSX) group (n=10).

RESULTS

The percentage of circulating CD25 after KT was significantly lower than that in the controls. There is no significant difference between KT and the controls s regard to circulating CD71. The percentage of CD25 was significantly increased in children with acute rejection compared with those without acute rejection. Calcineurin inhibitors (CNIs) decreased the frequency of CD25 but mammalian target rapamycin (mTOR) inhibitor did not. The proportion of CD25 significantly decreased in THYMO group during the first year after transplantation.

CONCLUSION

The frequency of circulating T cell activation marker CD25 in pediatric KT recipients is strongly affected by CNIs, and a high frequency of CD25 is associated with acute rejection during the early posttransplant period. The measurement of T cell activation markers, may become a useful immune monitoring tool after kidney transplantation.

A 12-month single arm pilot study to evaluate the efficacy and safety of sirolimus in combination with tacrolimus in kidney transplant recipients at high immunologic risk

The optimal immunosuppressive strategy for renal transplant recipients at high immunologic risk remains a topic of investigation. This prospective single arm pilot study was undertaken to evaluate the safety and efficacy of a combined tacrolimus and sirolimus regimen in recipients at immunological high risk and to compare outcomes with a contemporaneous control group received tacrolimus and mycophenolate mofetil. Patients that received a renal allograft between 2010 and 2011 at high risk (defined as panel reactive antibodies > 50%, 4 or more human leukocyte antigen mismatches, or retransplantation) were enrolled. All patients received basiliximab induction and corticosteroids. A total of 28 recipients treated with tacrolimus and sirolimus were enrolled in this study and 69 recipients were retrospectively reviewed as a control group. The sirolimus group showed a higher, but not statistically significant, incidence of biopsy proven acute rejection and a lower glomerular filtration rate than the control group. Furthermore, sirolimus group was associated with significant increases in BKV infection (P = 0.031), dyslipidemia (P = 0.004), and lymphocele (P = 0.020). The study was terminated prematurely due to a high incidence of adverse events. A de novo tacrolimus/sirolimus combination regimen may not be an ideal choice for recipients at high immunological risk.

Effectiveness of Intravenous Immunoglobulin Plus Plasmapheresis on Antibody-mediated Rejection or Thrombotic Microangiopathy in Iranian Kidney Transplant Recipient

Background:

Antibody mediated rejection (AMR) and thrombotic microangiopathy (TMA) after kidney transplantation are difficult to differentiate most of the times and both play important roles in kidney allograft loss. Common treatment strategies of these two conditions include plasmapheresis, intravenous immunoglobulin (IVIG) and rituximab.

Objectives:

This study was designed to assess the efficacy of routine treatment of AMR/TMA in Iranian kidney transplant recipients, which comprises of plasmapheresis and IVIG.

Patients and Methods:

This one-year cross-sectional study was performed in the Kidney Transplantation Ward of Imam-Khomeini Hospital Complex, Tehran, Iran. All kidney transplant recipients who were administered plasmapheresis and IVIG to treat definite or suggested AMR or TMA were assessed clinically and also evaluated on laboratory data.

Results:

During 2014, we encountered five patients with suspicious AMR or TMA at our kidney transplant center. Renal biopsy was performed for two of them, suggesting AMR for one patient and TMA for another patient. All patients were treated with plasmapheresis plus IVIG. In this center, as a routine practice, the cumulative dose of 2 g/kg of IVIG was divided to 300 - 400 mg/kg after each plasmapheresis. Only one out of the five patients showed response, albeit not completely.

Conclusions:

Due to daily plasmapheresis within the first several days after AMR or TMA, administering high amounts of the cumulative dose of IVIG after plasmapheresis may result in high amounts of IVIG withdrawal by plasmapheresis and response failure. Our suggestion is to reduce the IVIG dose after each plasmapheresis to 100 mg/kg (i.e. replacement dose) to reach a cumulative dose of 2 g/Kg. If plasmapheresis treatment is initiated sooner than the completion of the IVIG cumulative dose of 2 g/kg, the remaining dose can be administered during one injection.

Diagnostic Pitfalls and Challenges in Interpretation of Heart Transplantation Rejection in Endomyocardial Biopsies With Focus on our Experience

BACKGROUND

The current trend of heart transplantation in recent years has taken a quantum leap forward. We decided to look back at our experience in this center.

OBJECTIVES

Here, we focus on the diagnostic pitfalls and challenges in these biopsies.

PATIENTS AND METHODS

Forty two patients based on the standard protocol of heart transplantation group, yielded 63 biopsy samples over a period of 33 months (April 2010 - December 2012). The mean age was 30.4 years (ranging from 16 to 58 years) with 51 males (81%) and 12 females (19%). All the patients were examined periodically and biopsy samples were taken from the right ventricular wall.

RESULTS

Rarely fewer than three pieces of myocardial samples were procured. Scar, adipose tissues and blood clots may be seen instead. Quilty effect (nodular endocardial lesions composed of inflammatory cell infiltrates) was seen in 8 cases (12.7%). Other findings not directly related to rejection including early ischemic injury, Quilty effect and post-transplant lymphoproliferative disorders (PTLD) were not encountered.

CONCLUSIONS

Specimen inadequacy was not a major problem in our center. It poses a great limitation, because suboptimal specimens sometimes mislead the pathologist. Other findings especially Quilty effect were within the range defined for this finding.

Preoperative selective desensitization of live donor liver transplant recipients considering the degree of T lymphocyte cross-match titer, model for end-stage liver disease score, and graft liver volume

Several studies have suggested that a positive lymphocyte cross-matching (XM) is associated with low graft survival rates and a high prevalence of acute rejection after adult living donor liver transplantations (ALDLTs) using a small-for-size graft. However, there is still no consensus on preoperative desensitization. We adopted the desensitization protocol from ABO-incompatible LDLT. We performed desensitization for the selected patients according to the degree of T lymphocyte cross-match titer, model for end-stage liver disease (MELD) score, and graft liver volume. We retrospectively evaluated 230 consecutive ALDLT recipients for 5 yr. Eleven recipients (4.8%) showed a positive XM. Among them, five patients with the high titer (> 1:16) by antihuman globulin-augmented method (T-AHG) and one with a low titer but a high MELD score of 36 were selected for desensitization: rituximab injection and plasmapheresis before the transplantation. There were no major side effects of desensitization. Four of the patients showed successful depletion of the T-AHG titer. There was no mortality and hyperacute rejection in lymphocyte XM-positive patients, showing no significant difference in survival outcome between two groups (P=1.000). In conclusion, this desensitization protocol for the selected recipients considering the degree of T lymphocyte cross-match titer, MELD score, and graft liver volume is feasible and safe.

Outcomes of the Boston keratoprosthesis in jordan

Purpose:

To report the indications, outcomes, and complications of the Boston type I keratoprosthesis (KPro) from the first Jordanian study on the subject.

Materials and Methods:

A retrospective chart review was conducted on 20 eyes of 19 consecutive patients who had Boston type I KPro implantation at King Abdullah University Hospital. Surgeries were performed by the same surgeon (WS) from November 2007 to March 2010. Data collected included age, sex, primary indication, number of previous grafts, preoperative comorbidities, visual acuity before and after surgery, and complications.

Results:

The mean age of the participants was 51.7±19.9 years (range: 10–80 years). The mean follow-up was 18.1±9.5 months (range: 3–6 months). The most common primary corneal pathology was vascularized corneal opacity (40%). Best corrected visual acuity (BCVA) improved significantly in 85% of eyes; 65% had a BCVA of 20/200 or better and 25% had a BCVA of 20/50 or better. The most frequent complication was retroprosthesis membrane (RPM) formation, which occurred in 45% of eyes. Two eyes (10%) had implant extrusion and required further surgery.

Conclusion:

Boston Kpro offers a reasonably safe and effective solution for patients with corneal blindness in whom the prognosis for natural corneal grafting is poor.

Efficacy of anti-interleukin-2 receptor antibody (daclizumab) in reducing the incidence of acute rejection after renal transplantation

Background

Acute rejection remains a major problem in renal transplantation and represents one of the most important causes of chronic allograft dysfunction and late graft loss. Daclizumab is a genetically engineered human IgG1 monoclonal antibody that binds specifically to the α chain of the interleukin-2 receptor, and may thus reduce the risk of rejection after renal transplantation.

Objectives

The aim of this study was to examine the effect of daclizumab induction therapy combined with a triple immunosuppressive protocol including prednisolone,cyclosporine microemulsion (CsA), and mycophenolate mofetil (MMF), in reducing the incidence of acute rejection in recipients of living unrelated donor kidneys.

Patients and Methods

In this historical cohort study, 43 adult recipients of their first kidney allograft received daclizumab (three 1 mg/kg doses administered every 2 weeks) with triple immunosuppressive therapy (steroids, CsA, and MMF). This group was compared to 43 first-time graft recipients who received maintenance triple immunosuppressive therapy comprising steroids, CsA, and MMF. The end point was the incidence of biopsy confirmed acute rejection within 6 months after transplantation.

Results

At 6 months, 5 (11.6%) of the patients in the daclizumab group had biopsy-proven rejections, as compared to 14 (32.5%) in the control group (P = 0.017). The sex and the age of recipients had no impact on the incidence of acute rejection episodes in the two groups.

Conclusions

Adding interleukin-2 receptor antibody (daclizumab) to maintenance triple immunosuppressive therapy (prednisolone, CsA, and MMF) reduces the incidence of acute rejection episodes at 6 months in first-time transplant recipients of living unrelated donor.

Clinical significance of monitoring circulating CD4+CD25+ regulatory T cells in kidney transplantation during the early posttransplant period

The CD4(+)CD25(+) T regulatory cells (Tregs) play an important role in immune tolerance in experimental transplantation but the clinical significance of circulating Tregs in the peripheral blood is undetermined. In 50 kidney transplant (KT) recipients, 29 healthy controls and 32 liver transplant (LT) recipients, the frequency of Tregs was measured with flow cytometry before and after transplantation. In the KT recipients, IL-10 secretion was measured with an enzyme-linked immunospot (ELISPOT) assay. The median frequency of circulating Tregs before KT was similar to that in healthy controls but significantly lower than that in LT patients before transplantation. The frequency of Tregs was significantly decreased in patients with subclinical acute rejection compared with those without subclinical acute rejection. Calcineurin inhibitors (CNIs) and anti-CD25 antibody decreased the frequency of Tregs but mTOR inhibitor did not. The frequency of donor-specific IL-10 secreting cells did not correlate with the number of Tregs. The frequency of circulating Tregs in KT recipients is strongly affected by CNIs and anti-CD25 antibody, and a low frequency of Tregs is associated with subclinical acute rejection during the early posttransplant period.

Outcomes of penetrating keratoplasty for macular corneal dystrophy

PURPOSE

To report the outcomes of penetrating keratoplasty (PKP) in patients with macular corneal dystrophy (MCD).

METHODS

This retrospective case series includes consecutive patients with MCD who underwent PKP from 1986 to 2006 with at least 6 months' follow-up. Main outcome measures included best spectacle-corrected visual acuity (BSCVA), postoperative astigmatism and graft survival.

RESULTS

Sixty-two eyes of 39 patients with mean age of 34.0±10.5 (range 13-58) years at the time of keratoplasty were included for analysis. After a mean follow-up period of 52.0±47.3 (range 6-190) months, BSCVA improved from 1.4±0.4 logMAR (4/100) preoperatively to 0.2±0.3 logMAR (20/32) at final follow-up (P<0.001).Mean postoperative BSCVA was 0.15±0.40 logMAR in patients (36 eyes) aged less than 35 years at the time of surgery as compared to 0.26±0.25 logMAR in subjects (26 eyes) older than 35 years (P=0.005). Final astigmatism was comparable with different suturing techniques including separate, continuous, and combined sutures (P=0.9). All grafts were clear at final follow-up except a single case of MCD with visually insignificant recurrence.Episodes of immunologic graft rejection occurred in 12 eyes (19.4%) but none led to graft failure.

CONCLUSION

PKP for MCD entails favorable outcomes in terms of graft survival and visual improvement. Final visual acuity seems to be better when transplantation is performed before the age of 35 years.