Systemic cyclosporin treatment for high-risk corneal transplantation

Systemic Immunosuppression in Cornea and Ocular Surface Disorders: A Ready Reckoner for Ophthalmologists

Purpose: Many diseases of the cornea and ocular surface are manifestations of an underlying autoimmune process and require systemic immunosuppression for their management. These cases often present to a general ophthalmologist before being referred to an ocular immunologist or rheumatologist. However, the patients do need to be followed by the ophthalmologist to assess disease progression or for management of ocular co-morbidities and for taking care of ocular complications of the disease. Undeniably, there is a certain hesitance to promptly initiate them on systemic therapy because the literature regarding the indications, dosages, and side effects of this group of drugs is vast and dispersed.The aim of this review is to provide a source of ready reference for the general ophthalmologist as well as trainees and residents, on systemic immunosuppression for corneal and ocular surface disease. Methods: This review included 153 studies which were published as randomized controlled trials, systematic reviews, or as nonrandomized comparative studies (cohort or case-control series) on the topic of systemic immunosuppression in cornea and ocular surface disorders.Results: This review provides a concise summary of both the types of drugs and the common indications where they would be indicated, along with treatment and monitoring algorithms for each specific disease condition. The most used group of drugs are corticosteroids, which have significant side effects, particularly when administered systemically or for longer periods of time. To overcome this, steroid-sparing immunosuppressants are recommended. The four main classes of immunosuppressants used today are antimetabolites, T-cell inhibitors, alkylating agents and biologic agents. This review details the use of these drugs in ocular surface inflammation, including the dosing schedule, side effects and monitoring in allergic conjunctivitis, mucous membrane pemphigoid, peripheral ulcerative keratitis, immunological rejection against corneal allografts, anterior scleritis and aqueous deficiency dry eyes. Conclusions: This review provides an uncluttered and wholesome understanding of systemic immunosuppression in cornea and ocular surface diseases, with the hope that this will serve as a ready reckoner and help bridge the gap between ophthalmology and rheumatology for the betterment of our patients.

Efficacy of Immunosuppressants in High Rejection Risk Keratoplasty: A Meta-Analysis of Comparative Studies

PURPOSE

To evaluate the prophylactic effects of immunosuppressants in corneal graft rejection after high-risk penetrating keratoplasty.

METHODS

We searched PubMed, Embase, and the Cochrane Library for comparative studies published between 1989 and 2019 that evaluated the efficacy of immunosuppressants for high-risk corneal graft. The primary outcomes were the 1- and 3-year rejection rates. A fixed-effects or random-effects model was used on the basis of the I2 value, and the results were reported as odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Topical tacrolimus (FK506) was more effective than topical cyclosporine A (CsA) at reducing the 1-year graft rejection rate (OR: 0.17; 95% CI, 0.08-0.37, P<0.01). However, the combination of steroid with either topical FK506 (OR: 0.4; 95% CI, 0.16-1.04, P = 0.09) or CsA (OR: 0.74; 95% CI, 0.32-1.71, P= 0.48) did not show significant superiority in preventing immune rejection compared with steroid monotherapy. Mycophenolate mofetil (MMF) was more effective than CsA at reducing the 1-year graft rejection rate (OR: 2.67; 95% CI, 1.50-4.76, P<0.01). However, MMF was not significantly superior to CsA at reducing the 3-year graft rejection rate (OR: 1.21; 95% CI, 0.45-3.25, P = 0.71). For reducing the 1-year rejection rate, MMF (OR: 0.12; 95% CI, 0.03-0.39, P < 0.01) and CsA (OR: 0.28; 95% CI, 0.10-0.76, P = 0.01) were each more effective than the control groups.

CONCLUSIONS

FK506 eye drops, MMF, and systemic CsA were considered to be promising management to prevent rejection in high-risk penetrating keratoplasty in the present study.

Systemic Immunosuppression in High-Risk Penetrating Keratoplasty: A Systematic Review

Cornea transplantation has a high success rate and typically only requires topical immunomodulation. However, in high-risk cases, systemic immunosuppression can be used. We conducted a systematic review on the efficacy and side effects of systemic immunosuppression for high-risk cornea transplantation. The study population was 18 years old or older with a high-risk transplant (two or more clock hours of cornea vascularization or a previous failed graft or a graft needed because of herpes simplex keratitis). A comprehensive search strategy was performed with the help of an information specialist and content experts from ophthalmology. All study designs were accepted for assessment. Level 1 and level 2 screening was performed by two reviewers followed by data abstraction. Forest plots were created whenever possible to synthesize treatment effects. Quality assessment was done with a Downs and Blacks score. From 1,150 articles, 29 were ultimately used for data abstraction. The odds ratios (ORs) for clear graft survival in cyclosporine and controls were 2.43 (95% CI: 1.00 - 5.88) and 3.64 (95% CI: 1.48 - 8.91) for rejection free episodes. Mycophenolate mofetil (MMF) significantly improved the rejection free graft survival rates at 1 year (OR: 4.05, 95% CI: 1.83 - 8.96). The overall results suggested that both systemic cyclosporine and MMF improved 1-year rejection free graft survival in high-risk keratoplasty. Cyclosporine also significantly improved clear graft survival rates at 1 year; however, there were insufficient data to analyze the same in the MMF group. Higher quality studies are needed to understand this issue better.

Adverse effects of low-dose systemic cyclosporine therapy in high-risk penetrating keratoplasty

PURPOSE

The purpose of this study was to investigate the adverse effects of low-dose oral cyclosporine (CsA) therapy following high-risk corneal transplantation.

METHODS

The medical records from 88 subjects who had undergone high-risk penetrating keratoplasties and had been administered oral CsA were retrospectively analyzed. High risk was defined as a history of graft rejection, three or more quadrants of vascularization, or the presence or history of intraocular inflammation. An initial CsA dose of 3-5 mg/kg per day was given for 3-7 days, followed by 2.5-3.5 mg/kg per day for approximately 1 month. The concentration of CsA was maintained at the target trough level of 120-150 ng/ml for at least 6 months or until serious complications developed. The relationship between the cumulative dose and duration of CsA administration and the adverse systemic effects, including the frequency of herpes keratitis, was evaluated. The incidence of herpes keratitis in the study subjects was compared with the incidence in 185 patients who had not received CsA therapy following penetrating keratoplasty.

RESULTS

The mean survival time of the grafts was 33.6 months. Adverse effects occurred in 81.8 % of subjects. Hypertension, elevated liver enzyme levels, elevated serum creatinine level, and decreased absolute neutrophil count (ANC) were observed in 14.8, 6.8, 5.7, and 5.7 % of subjects, respectively. Simvastatin-induced rhabdomyolysis also developed in one case. Some patients exhibited minor complications, with gastrointestinal problems and hypertrichosis recorded in 5.7 and 3.4 % of subjects, respectively. Hypertension and hepatotoxicity most frequently occurred after 4 to 8 weeks of medication, while ANC decrease and nephrotoxicity generally developed after 24 weeks of treatment, with incidence related to the cumulative dose. Herpes keratitis occurred more frequently (31.8 %) in the CsA-treated subjects than in subjects that did not receive CsA therapy (p = 0.005). Most of the adverse effects were reversed after discontinuation of CsA therapy.

CONCLUSION

The results of this study suggest that low-dose oral CsA therapy may induce various adverse effects, the most common of which are herpes keratitis and hypertension.

Efficacy and safety of microspheres of cyclosporin A, a new systemic formulation, to prevent corneal graft rejection in rats

PURPOSE

To evaluate the efficacy and safety of a new systemic formulation of cyclosporin A (CsA)-loaded microspheres in a rat model of penetrating keratoplasty rejection.

METHODS

Female Lewis rats received orthotopic corneal allografts from inbred female Fisher donors. The rats were divided into three groups: 1, untreated controls; 2, daily subcutaneous injection of 10 mg/kg of the commercially intravenous CsA formulation starting after surgery (time 0) and for 15 days; and 3, one subcutaneous injection of 150 mg/kg of CsA microspheres. The grafts were evaluated clinically for 30 days and the rejection index, mean survival time, and rejection rate were calculated. Serum levels of CsA were measured at 5, 10, 15, 20, and 30 days in groups 2 and 3. Eyes, liver, and kidneys were histologically evaluated at the end of the experiment.

RESULTS

Graft rejection was significantly reduced in group 3 at day 30 (P < 0.05) and serum levels of CsA were constant (range, 73.28 +/- 43.93 to 183.33 +/- 83.69 ng/ml). High levels (>3000 ng/ml) were obtained in group 2 as long as CsA was injected. Both formulations delayed rejection onset, but only the microspheres decreased the rate of corneal graft rejection (100% in group 2 and 70% in group 3 at day 30). Histologic examination showed no hepatic lesions with either formulation, but both resulted in deposition of a hemoglobin-like material in the kidneys.

CONCLUSIONS

Although subcutaneous CsA-loaded microspheres delay rejection onset and decrease the rate of corneal graft rejection in an orthotopic keratoplasty rejection model in rats, administration of the microspheres did not prevent acute renal toxicity.

Anaesthesia for patients with a transplanted organ

Increasing numbers of individuals leading normal lives have transplanted organs. They may appear in any hospital for treatment of trauma or general diseases. Common anaesthesia methods can be used for these patients, but safe conduct of anaesthesia requires knowledge of the immunosuppression, risk factors, and altered physiology or drug actions. This article reviews the anaesthesia-related literature on patients with transplanted organs.

Prevention of high risk corneal graft rejection using cyclosporine A (CsA) incorporated into a collagen matrix

The aim of this work was to compare the efficacy of cyclosporine (CsA) collagen shields and fragments in suppressing experimental allograft rejection in an animal model for high risk keratoplasty. Altogether 23 experimental animals were treated either with plain collagen shields, oral cyclosporine, collagen CsA shields, or with CsA collagen fragments after corneal transplantation (PKP) in previously vascularized corneas. The study medications were started immediately following PKP. For these animals slit lamp examinations were performed twice a week for the duration of the experiment and the signs of corneal rejection were observed. The animals were followed until an irreversible rejection or until the end of the experiment (14-149 days). The inflammation of the graft was also evaluated histologically when animals were sacrificed. The grafts treated with plain collagen shields all were rejected within 36 days, and the mean graft survival time for these corneas was 25 days. Five transplants that were treated with oral CsA had better survival, and two of five grafts stayed clear until postoperative day 119, when the treatment was stopped. The best graft survival was seen in grafts treated with CsA collagen fragments and all these stayed clear up to 77 days postoperatively. The treatment of the grafts with CsA collagen shields was almost as effective as with CsA fragments, and first signs of rejection appeared as late as nine weeks postoperatively in two of seven grafts. The other of these rejected corneas were later treated with CsA collagen fragments and showed a dramatic improvement in transparency of the cornea and disappearance of inflammation of the graft. The discontinuation of study medication caused an irreversible rejection to appear in a previously clear graft that had been treated successfully with any study medication. We conclude that topical CsA in shields or in fragments will provide a significant advance over systemic CsA alone, and that CsA fragments appear to be as effective as shields in preventing corneal allograft rejection.