Sirolimus-associated eyelid edema in kidney transplant recipients

Sirolimus and mTOR Inhibitors: A Review of Side Effects and Specific Management in Solid Organ Transplantation

Inhibitors of mechanistic target of rapamycin (mTOR inhibitors) are used as antiproliferative immunosuppressive drugs and have many clinical applications in various drug combinations. Experience in transplantation studies has been gained regarding the side effect profile of these drugs and the potential benefits and limitations compared with other immunosuppressive agents. This article reviews the adverse effects of mTOR inhibitors in solid organ transplantation, with special attention given to mechanisms hypothesized to cause adverse events and their management strategies.

[Pemetrexed-induced eyelid edema]

BACKGROUND

Drug-induced eyelid edemas are rare. Herein, we describe a patient who developed this type of edema under chemotherapy.

PATIENTS AND METHODS

A 56-year-old male patient with a history of hypertension and adenocarcinoma of the lung with brain metastases consulted for incipient non-itchy eyelid edema with progressive worsening. The swelling occurred after 3 cycles of pemetrexed-carboplatin. There was no evidence of any other cause of edema. A diagnosis of pemetrexed-induced eyelid edema was made. Given the efficacy of this treatment and the patient's consent thereto, it was maintained.

DISCUSSION

Palpebral edemas secondary to pemetrexed are very rare, with only 22 published cases in the literature. Other differential diagnoses must be ruled out before considering this etiology. The pathogenesis of eyelid edema remains unknown. One hypothesis is capillary protein leakage inducing swelling in soft tissue and non-malignant effusion, as has been suggested for docetaxel. Other agents such as tyrosine kinase inhibitors (imatinib and nilotinib) and mTOR inhibitors (sirolimus) may also cause eyelid edema. Treatment of eyelid edema is difficult and one case of surgical treatment has been published with good results and no recurrence after 6 months.

A Case of Everolimus-Induced Eyelid Edema

Everolimus is a newer generation mammalian target of rapamycin inhibitor approved for immunosuppressive use in a number of advanced medical conditions. The authors report a unique case of persistent eyelid edema believed to be related to the immunosuppressive therapy. The therapy was being well tolerated despite the persistent eyelid edema, so the patient underwent a bilateral upper eyelid blepharoplasty. The patient responded well with resolution of her eyelid dermatochalasis and markedly decreased edema. Everolimus-induced eyelid edema should be recognized by clinicians as a potential side effect of the medication. Surgical excision of excess eyelid tissue by blepharoplasty can be a successful way to manage this side effect.Everolimus (zortress) was initially approved as an immunosuppressive agent for renal transplantation patients. Approval for the treatment of subependymal giant cell astrocytomas associated with tuberous sclerosis, progressive metastatic pancreatic neuroendocrine tumors, human epidermal growth factor receptor 2 negative breast cancer in postmenopausal woman, liver transplantation patients, and well-differentiated neuroendocrine tumors of gastrointestinal or pulmonary origin has followed., Everolimus is a derivative of sirolimus (rapamune), and similar to sirolimus acts as an inhibitor of mammalian target of rapamycin. Few prior studies have reported eyelid edema from sirolomus. Many prior medications have been implicated in eyelid edema formation. To date, periocular edema has not been reported as a side effect of everolimus. We report a patient with bilateral upper eyelid edema associated with everolimus therapy requiring surgical intervention to ameliorate the significant skin redundancy and the visual field defect. This report complies with the Declaration of Helsinki and Health Insurance Portability and Accountability Act regulations.

Immunosuppressant-Related Lower Eyelid Edema in Transplant Patients

Solid organ transplantation is the preferred method of treatment for a number of advanced medical conditions, but it requires systemic immunosuppression to prevent transplant rejection. The authors report 2 unique cases of persistent eyelid edema following solid organ transplantation believed to be related to their systemic immunosuppression. The eyelid findings developed after initiation of the immunosuppressant sirolimus. In 1 patient, the eyelid edema has persisted despite discontinuation of the medication. In the second patient, the immunosuppression could not be altered; therefore, he underwent surgical excision of the edematous lower eyelid. Sirolimus associated eyelid edema is an important medication side effect for ophthalmic and eyelid specialists to consider when a patient with a history of organ transplantation presents with localized noninflamed eyelid edema. This edema can persist despite discontinuation of the medication. Surgical excision of the edematous eyelid can achieve good results.

Oedema, solid organ transplantation and mammalian target of rapamycin inhibitor/proliferation signal inhibitors (mTOR-I/PSIs)

Mammalian target of rapamycin inhibitor (mTOR-I)/proliferation signal inhibitors (PSI) including sirolimus and everolimus represent a new class of drugs increasingly used in solid-organ transplantation as alternatives to calcineurin inhibitors for patients with renal dysfunction, transplant coronary arterial vasculopathy or malignancy. The most frequently occurring mTOR-I/PSI-related adverse events are similar to those associated with other immunosuppressive therapies, but some side effects are more characteristic of proliferation signal inhibitors (e.g. lymphocele, arthralgia, oedema and hyperlipidaemia). The present paper review incidence, clinical presentation and mechanism of oedema within the clinical experience of mTOR-I/PSI in solid organ transplantation.

Mucocutaneous disorders in renal transplant recipients receiving sirolimus-based immunosuppressive therapy: a prospective, case-control study

BACKGROUND

Sirolimus (SRL) has some dermatologic complications including acneiform eruptions, edema, aphthous ulceration, and onychopathy. However, controlled studies reporting the prevalence and clinical characteristics of mucocutaneous disorders are scarce.

OBJECTIVE

To investigate the prevalence and clinical spectrum of mucocutaneous disorders in renal transplant recipients (RTRs) receiving SRL and to compare the findings with those in RTRs not receiving SRL.

METHODS

Fifty RTRs (35 men, 15 women; mean age, 34.6 ± 11.6 yr) receiving SRL, 50 RTRs (36 men, 14 women; mean age, 34.4 ± 11.3 yr) not on SRL were screened for mucocutaneous disorders.

RESULTS

In RTRs receiving SRL, skin infection (78%) was the most common dermatologic disorder followed by facial hyperpigmentation (50%) and acneiform eruption (46%). Herpes simplex virus infections (14%) and seborrheic dermatitis (38%) were significantly more common in RTRs on SRL (p < 0.05); the frequencies of edema, aphthous ulceration, acne, and longitudinal nail ridging were similar in both groups (p > 0.05).

LIMITATIONS

This study had a small sample size. The investigator was not blinded to immunosuppressive treatment protocols.

CONCLUSION

Renal transplant recipients receiving SRL are more likely to develop seborrheic dermatitis and herpes simplex virus infections than those not taking SRL. Whereas, they are not more prone to edema, aphthous ulceration, acne, or longitudinal nail ridging.

Rapamycin inhibits VEGF-induced microvascular hyperpermeability in vivo

OBJECTIVE

To test the hypothesis that rapamycin inhibits induced microvascular hyperpermeability directly in vivo.

METHODS

Male golden Syrian hamsters (80-120 g) were treated with either rapamycin (at 0.1, 0.5, 2, and 10 mg/kg i.p.) or vehicle at 24 hours and at 1 hour prior to preparation of the cheek pouch. Caveolin-1 scaffolding (1 mg/kg; positive inhibitory control) was injected i.p. 24 hours prior to the experiment. 10(-8) M vascular endothelial growth factor (VEGF) or 10(-7) M platelet-activating factor (PAF) were topically applied to the cheek pouch. Microvascular permeability and arteriolar diameter were assessed using integrated optical intensity (IOI) and vascular wall imaging, respectively.

RESULTS

Rapamycin at 0.1 and 0.5 mg/kg significantly reduced VEGF-stimulated mean IOI from 63.0 +/- 4.2 to 9.7 +/- 5.0 (85% reduction, P < 0.001) and 3.6 +/- 2.7 (95% reduction, P < 0.001), respectively. Rapamycin at 2 mg/kg also lowered VEGF-stimulated hyperpermeability (40% reduction, P < 0.05). However, 10 mg/kg rapamycin increased VEGF-induced microvascular hyperpermeability. Rapamycin at 0.5 mg/kg attenuated VEGF-induced vasodilation and PAF-induced hyperpermeability, but did not inhibit PAF-induced vasoconstriction.

CONCLUSIONS

At therapeutically relevant concentrations, rapamycin inhibits VEGF- and PAF-induced microvascular permeability. This inhibition is (i) a direct effect on the endothelial barrier, and (ii) independent of arteriolar vasodilation. Rapamycin at 10 mg/kg stimulates effectors that increase microvascular permeability.

Conversion to sirolimus for chronic allograft nephropathy and calcineurin inhibitor toxicity and the adverse effects of sirolimus after conversion

BACKGROUND

Chronic allograft nephropathy and calcineurin inhibitor toxicity may cause graft loss. After kidney transplantation, especially among those patients with chronic allograft nephropathy, sirolimus may be a good alternative to calcineurin inhibitors. Unlike calcineurin inhibitors, sirolimus is devoid of significant nephrotoxicity, but approximately 30% to 50% of patients on sirolimus therapy display mild or severe adverse effects. We sought to report our experience with sirolimus conversion among patients with chronic allograft nephropathy as well as the mild versus severe adverse effects that limit the drug's use.

MATERIALS AND METHODS

We analyzed the outcomes of 88 patients (64 men and 24 women) of overall mean age of 35.9 +/- 9.9 years (range, 21-59 years) who had undergone kidney transplantation. Immunosuppressive therapy had been converted from a calcineurin inhibitor to sirolimus because of biopsy-proven chronic allograft nephropathy, calcineurin inhibitor toxicity, or presence of malignancy. We excluded patients with prior acute rejection episodes. Subjects were divided into two groups with respect to their creatinine levels: Group A < 2 mg/dL and Group B >or= 2 mg/dL. After conversion to sirolimus, possible adverse effects of sirolimus were evaluated at the follow-up inset. Each patient underwent a physical examination, and estimation of serum lipid and electrolyte levels as well as hemoglobin concentration.

RESULTS

At the time of conversion of the 88 renal transplant patients, their mean duration after grafting was 48 +/- 15 months (range, 4-296). The prior treatment consisted of a calcineurin inhibitor, prednisolone, and mycophenolate mofetil. After conversion, the calcineurin inhibitor was stopped and sirolimus was begun. The 48 Group 2 patients (34 men, 14 women) of overall mean posttransplant time of 22.7 +/- 14.6 months who underwent conversion displayed a mean serum creatinine increase to 3.2 +/- 1.4 mg/dL, including 17 subjects who underwent rejection. The 40 Group 1 patients (30 men, 10 women) with a mean overall posttransplant period of 67.6 +/- 49.9 months showed an fall in serum creatinine level to 1.4 +/- 0.5 mg/dL among only 3 patients. While 5/88 patients showed no increase in proteinuria (5.6%); 83 (94.4%) did experience it. Proteinuria increased from a mean of 192 +/- 316 to 449 +/- 422 mg/d. Only three patients displayed heavy proteinuria (>3 g/d); sirolimus was discontinued for this reason. Proteinuria was well controlled in the other patients with angiotensin-converting enzyme and/or angiotensin II receptor inhibitor agents. After sirolimus conversion, serum cholesterol levels increased from 187 +/- 42 to 214 +/- 52 mg/dL, and serum triglyceride levels increased from 161 +/- 61 to 194 +/- 102 mg/dL. All but four patients responded to statin therapy, with serum lipid levels falling to acceptable levels. Another four patients developed unilateral lower extremity edema with sirolimus discontinued for this reason. One patient displayed generalized arthralgia.

CONCLUSION

Chronic allograft nephropathy or calcineurin inhibitor toxicity can lead to loss of graft kidney function. Calcineurin inhibitor toxicity can lead to chronic allograft nephropathy. Patients with a low baseline serum creatinine level who undergo sirolimus conversion showed stabilized kidney function. Late conversion of patients with a serum creatinine above 2 mg/dL face a risk of graft failure. Sirolimus displayed a limited incidence of serious adverse effects; mild or moderate adverse effects, such as hyperlipidemia and proteinuria, were easily controlled with countermeasure therapy.

The use of everolimus in renal-transplant patients

Despite advances in immunosuppressive therapy, long-term renal-transplantation outcomes have not significantly improved over the last decade. The nephrotoxicity of calcineurin inhibitors (CNIs) is an important cause of chronic allograft nephropathy (CAN), the major driver of long-term graft loss. Everolimus is a proliferation signal inhibitor with a mechanism of action that is distinct from CNIs. The efficacy and tolerability of everolimus in renal-transplant recipients have been established in a wide range of clinical trials. Importantly, synergism between everolimus and the CNI cyclosporine (CsA) permits CsA dose reduction, enabling nephrotoxicity to be minimized without compromising efficacy. Currently, everolimus is being investigated in regimens where reduced exposure CNIs are used from the initial post-transplant period to improve renal function and prevent CAN. By inhibiting the proliferation of smooth muscle cells, everolimus may itself delay the progression or development of CAN. Although everolimus is associated with specific side effects, these can generally be managed. By targeting the main causes of short- and long-term graft loss, everolimus has a key role to play in renal transplantation, which is being explored further in a number of ongoing Phase III–IV trials.

Sirolimus-associated lymphoedema: eight new cases and a proposed mechanism

Sirolimus, an inhibitor of the mammalian target of rapamycin (mTOR), is increasingly used as an agent for post-transplant immunosuppression and the treatment of solid organ and haematological malignancies and hamartomas. Its advantages include a lack of nephrotoxicity and a lower incidence of nonmelanoma skin cancers; adverse effects include delayed wound healing, increased lymphocoele formation and rarely lymphoedema. We report a series of eight cases of severe, sustained, unilateral and bilateral lymphoedema in patients receiving sirolimus for post-transplant immunosuppression, classify their lymphoscintigraphy findings and propose a mechanism of aetiology based on the interaction of mTOR with key mediators of lymphangiogenesis.

The effects of sirolimus on wound healing in dermatologic surgery

BACKGROUND

Sirolimus, a TOR (target of rapamycin)-binding immunosuppressant, has been associated with wound healing complications; however, its effects have not been documented in dermatologic surgery.

OBJECTIVE

The objective was to determine the effect of sirolimus on wound healing in dermatologic surgery.

METHODS AND MATERIALS

Databases at Mayo Clinic were queried for organ transplant recipients undergoing dermatologic surgery. Medical records were reviewed retrospectively, and telephone interviews were conducted. Patients receiving sirolimus were compared with patients not receiving sirolimus.

RESULTS

Postoperative infections occurred in 19.2% of the sirolimus group (n=26) and 5.4% of the controls (n=37; p=.11; odds ratio [OR], 4.2; 95% confidence interval [CI], 0.7-23.4). The incidence of wound dehiscence was greater in the sirolimus group (7.7% vs. 0%; p=.17; OR, 7.7; 95% CI, 0.4-166.3).

CONCLUSION

No significantly increased risk of wound complications was found in organ transplant recipients receiving sirolimus while undergoing dermatologic surgery. However, this study was retrospective and had a small sample size. A larger study is necessary for corroboration.

Lymphedema: an unusual complication of sirolimus therapy

INTRODUCTION

Lymphedema is an increasingly observed complication of sirolimus (SIR) therapy. In this report, we describe four renal recipients with SIR-induced lymphedema of varying severity.

CASES REPORTS

Patient 1, a 38-year-old man developed lymphedema of the left upper limb after being exposed to SIR for 30 months (mean daily Rapamune dose, 3 mg; trough level, 10-18 ng/mL). Venography and duplex ultrasound were normal. Lymphangiography was showed delayed lymphatic drainage. SIR was replaced with Prograf with significant improvement in the lymphedema over the next 6 months. Patient 2, a 26-year-old woman, developed lymphedema of the left lower limb at 24 months after starting SIR (mean daily dose, 3 mg; trough level, 10-15 ng/mL). Lymphangiography showed delayed drainage of lymphatics in the left lower limb. The patient was shifted to Prograf and there was some improvement over the next 4 months. Patient 3, a 28-year-old man, developed lymphedema of the left upper limb at 24 months after the start of SIR (mean daily dose, 2 mg, trough level, 6-15 ng/mL). Lymphangiography showed evidence of lymphatic obstruction. SIR was changed to cyclosporine with only mild improvement in lymphedema over the next 6 months. Patient 4, a 46-year-old man, developed lymphedema of the right upper limb at 7 months after starting SIR (mean daily dose, 6 mg; trough level, 10-16 ng/mL). Lymphangiography showed complete blockage of the lymphatic channels. SIR was changed to cyclosporine and there was mild improvement in lymphedema over the next 8 to 10 months.

CONCLUSION

The exact mechanism of SIR-induced lymphedema is unknown. The absence of other demonstrable etiologies and spontaneous improvement after discontinuation of SIR suggest that this drug was the responsible factor in these four patients. It occurred 7 to 30 months after transplantation. This is the fourth such report in the literature to the best of our knowledge.

Sirolimus-induced Alveolar Hemorrhage

Sirolimus is a well-known, potent immunosuppressant that is widely used in solid-organ transplantation, but it is not without potential side effects. A rare but devastating adverse effect is sirolimus-associated pulmonary toxicity. We report a case of sirolimus-induced diffuse alveolar hemorrhage confirmed by bronchoscopic findings (after other possible etiologies were ruled out) and by clinical and radiographic resolution of the pulmonary signs and symptoms a few days after sirolimus administration was stopped. This case and the existing literature on this topic suggest that sirolimus-induced pulmonary toxicity should be suspected in any patient taking immunosuppressants and who develops unexplained pulmonary symptoms.

Use of sirolimus in solid organ transplantation

Sirolimus is a mammalian target of rapamycin (mTOR) inhibitor that inhibits cell cycle progression and has proven to be a potent immunosuppressive agent for use in solid organ transplant recipients. The drug was initially studied as an adjunct to ciclosporin (cyclosporine) to prevent acute rejection in kidney transplant recipients. Subsequent studies have shown efficacy when combined with a variety of other immunosuppressive agents. The most common adverse effects of sirolimus are hyperlipidaemia and myelosuppression. The drug has unique antiatherogenic and antineoplastic properties, and may promote immunological tolerance and reduce the incidence of chronic allograft nephropathy. Although sirolimus is relatively non-nephrotoxic when administered as monotherapy, it pharmacodynamically enhances the toxicity of calcineurin inhibitors. Ironically, the drug has been used to facilitate calcineurin inhibitor-free protocols designed to preserve renal function after solid organ transplantation. Whether sirolimus can be used safely over the long term with low doses of calcineurin inhibitors requires further study. The use of sirolimus as a corticosteroid-sparing agent also remains to be proven in controlled trials. Postmarketing studies have revealed a number of unforeseen adverse effects including impaired wound healing and possibly proteinuria, oedema, pneumonitis and thrombotic microangiopathy. Overall, sirolimus is a powerful agent when used judiciously with other available immunosuppressants. As is true for all immunosuppressive drugs available for treatment of solid organ transplant recipients, the efficacy of the drug must be balanced against its considerable adverse effects.

Acne in recipients of renal transplantation treated with sirolimus: Clinical, microbiologic, histologic, therapeutic, and pathogenic aspects

We evaluated the clinical characteristics of sirolimus-induced acne in 80 recipients of renal transplantation. It developed in 36 of 48 (75%) men and 2 of 32 (6%) women. Lesion locations and clinical, bacteriologic, and histologic features differentiated sirolimus-induced acne from acne vulgaris, but therapeutic management was similar. The main limitation for this study was the absence of a control group without sirolimus. Epidermal growth factor inhibition by sirolimus is a plausible explanation for this acne.

Onychopathie associée au sirolimus chez les transplantés rénaux

INTRODUCTION

A large number of drugs may be responsible for the development of nail changes. Sirolimus is an immunosuppressive drug recently developed in organ transplantation. Herein, we evaluate sirolimus-induced nail abnormalities in renal transplant recipients.

PATIENTS AND METHODS

The nails of 80 consecutive renal transplant recipients receiving sirolimus have been evaluated in a systematic dermatological study in 2003. The patients were mainly men (60%) with a mean age of 48 years. The mean duration of the graft was 6 years and of sirolimus treatment 18 months. Mycophenolate mofetil and steroids were combined with sirolimus in 86% of patients.

RESULTS

Fifty-seven patients (74%) complained for nail alterations. The most frequent anomalies (88%) were matrix alterations including slow growth, onychomalacia, onychorrexis, and leukonychia. Nail bed alterations (onycholysis), vascular phenomenon (erythema, splinter hemorrhages), and periungual anomalies (mainly pyogenic granulomas) were observed in 42, 42 and 19% of cases respectively. One observation of type 1 photo-onycholysis was described.

DISCUSSION

This study reports a new drug-induced onychopathy. Responsibility of sirolimus is highly suggested. The main pathogenesis hypothesis to explain these nail alterations is inhibition of EGF (epidermal growth factor) pathway by sirolimus.

Liver transplantation for hepatitis C virus related liver disease

Liver transplantation is a useful treatment for end stage liver disease of all aetiologies but recurrent disease presents an ongoing challenge, particularly for hepatitis C virus (HCV) where recurrence is almost universal. Immunosuppression is needed for all patients after transplantation and should be tailored to the individual patient, with particular problems being noted for those with HCV. The longer term effects of immunosuppression, particularly renal failure and the adverse effects of certain treatments on the liver graft, have become more important as survival improves and results are studied for longer periods after transplantation.

Sirolimus: Its role in nephrology (Review Article)

Sirolimus (Rapamycin, Wyeth Pharmaceuticals Australia Pty Ltd, Baulkham Hills, NSW, Australia) (SRL) has received increasing attention as an immunosuppressant in renal and other solid organ transplantation. Sirolimus is the first marketed agent in a new class of drugs with a novel mechanism of action. Sirolimus binds, like tacrolimus, to a member of the FK binding protein (FKBP) family. The SRL/FKBP complex binds to the protein kinase mTOR. Binding to mTOR blocks activation of signal transduction pathways causing arrest of the cell cycle in the G1 phase. It is now known that mTOR is a central regulator of cell growth and proliferation. The immunosuppressive properties of SRL are due primarily to blockade of interleukin-2 (IL-2)-induced proliferation of T cells. There is still much to be learnt about how best to use the drug. The key advantage over the current choice of immunosuppressive agents is the ability to preserve renal function and pathology while producing excellent rejection-free, graft survival rates. Thus, SRL may find its pivotal role as a calcineurin inhibitors replacement in patients whose grafts are affected by chronic allograft nephropathy. A second major driver for use may prove to be the impact of SRL on cancer incidence and prognosis. Studies still need to be performed to evaluate the best timing for commencement of SRL and the optimal dosage to minimize side-effects.

Severe limb lymphedema in sirolimus-treated patients

We report two kidney transplant recipients who developed severe limb lymphedema under sirolimus (SRL) immunosuppression. The patients received SRL 10 and 2 mg/d to achieve target levels of 10 to 20 ng/mL with tapering doses of prednisone. Renal function and drug levels were monitored monthly. Patient 1 developed lymphedema of the left upper limb 3 years posttransplantation, after having been exposed to high SRL doses in the preceding 2 years (mean SRL dose-9.5 mg/d, mean trough level-26.3 ng/mL, mean serum creatinine-1.63 mg/dL). In patient 2 lymphedema of both upper and lower right limbs occurred 18 months posttransplantation (mean SRL dose-3.2 mg/d, mean trough level-8.8 ng/mL, mean serum creatinine-2.9 mg/dL). Hypercholesterolemia and hypertriglyceridemia were also observed in both patients before SRL reduction/conversion. No signs of hematopoietic toxicity were observed. In both patients magnetic resonance (MR) angiography of the limb was negative for vascular obstruction, and lymphoscintigraphy revealed lymphatic obstruction. In patient 1 lymphedema improved significantly following SRL reduction and lymphatic drainage massage therapy. Patient 2 was converted to cyclosporine (CsA) improving markedly after conversion. Hypercholesterolemia and hypertriglyceridemia also improved significantly in both patients after reduction/conversion. We conclude that SRL may facilitate the occurrence of lymphatic obstruction by mechanisms that are presently unexplained. Lymphedema of the limbs in renal transplant recipients under SRL treatment, especially if on the same side as the hemodialysis access, should warn the transplant physician to rapidly reduce or withdraw SRL before the occurrence of complete obstruction.

Patterns of pulmonary complications associated with sirolimus

Sirolimus inhibits human fibroblast cell proliferation in cell cultures from transbronchial biopsies of lung transplant recipients. However, a few cases of interstitial pneumonitis and bronchiolitis obliterans organizing pneumonia have been recently described in solid organ transplant recipients, including a fatality in a heart transplant recipient. We studied the patterns of pulmonary adverse effects associated with sirolimus in 4 renal transplant recipients who developed pulmonary opacities on chest radiograph, which were proved to be noninfectious in origin. Lung biopsy was performed to obtain histological diagnosis (3 interstitial pneumonitis, 1 necrotizing vasculitis). Symptoms were dyspnea (4), cough (2), hemoptysis (1), fever (1) and eyelid edema (1). Those with interstitial pneumonitis had bilateral basal opacities on chest X-ray, and histopathology showed mild lymphoplasmocytic interstitial inflammation, scattered intraalveolar epitheloid granulomas and a focal pattern of organizing pneumonia. Serum C-reactive protein (CRP) was elevated and bronchoalveolar lavage revealed lymphocytosis (77, 79.5 and 31%). The fourth patient had an opacity localized in the upper lobe, which progressed to both the lower lobes, and histopathology showed multifocal necroses of lung tissue with lymphoplasmocytic vasculitis and scattered granulomas. In this patient, the serum CRP level was not elevated and bronchoalveolar lavage was normal. Pulmonary symptoms and opacities on chest radiograph resolved and the serum CRP level became normal after sirolimus was stopped in all patients. Sirolimus may be a cause of interstitial pneumonitis or pulmonary vasculitis, and withdrawal of sirolimus is therapeutic.

Clinical Experience with Everolimus (Certican): Optimizing Dose and Tolerability

BACKGROUND

Everolimus (Certican), a novel proliferation signal inhibitor, allows calcineurin inhibitor dose reduction in transplant patients, minimizing risk of nephrotoxicity without loss of immunosuppressive efficacy. As a result of its mode of action, this class of agent (i.e., everolimus and sirolimus) is associated with certain adverse events (e.g., lymphocele, arthralgia, edema and hyperlipidemia).

METHODS

Three case studies from within an everolimus Phase III trial (A2306) are presented with the aim of illustrating how treatment-related adverse events can be managed.

RESULTS

The combination of everolimus with reduced-exposure cyclosporine was efficacious in these patients. One experienced mild acute rejection that was managed with steroid boluses. All have acceptable graft function during follow-up to date. Moderate lymphocele either resolved spontaneously or was easily managed by povidine-iodine instillations. One patient developed serious early lymphocele that, unusually, required surgical intervention. Everolimus dose reduction or withdrawal was not necessary to effectively manage lymphocele of any severity. A case of bilateral multiple arthralgia was effectively managed with everolimus dose reduction, but still maintained everolimus trough blood levels at approximately 3 ng/ml. Eyelid and ankle edemas were also easily managed with low dose furosemide, preferably coupled with cyclosporine and everolimus dose reduction. Hyperlipidemia responded to statin therapy.

CONCLUSIONS

Everolimus-related adverse events can be effectively managed either with other treatments or, where necessary, by everolimus dose reduction, without loss of efficacy. Discontinuing everolimus therapy is generally not necessary.

Cutaneous adverse events in renal transplant recipients receiving sirolimus-based therapy

BACKGROUND

Sirolimus is an immunosuppressive drug recently developed for organ transplantation. Its mechanism of action, independent of calcineurin, is different from that of cyclosporine and tacrolimus, two calcineurin inhibitors (CIs). Because the toxicity of CIs is partly the result of calcineurin blockade, sirolimus exhibits a different toxicity profile. In this study, we evaluated the profile, frequency, and severity of cutaneous adverse events in renal transplant recipients receiving sirolimus-based therapy.

PATIENTS AND METHODS

A systematic and in-depth evaluation of skin, mucous membranes, nails, and hair was performed in 80 renal transplant recipients receiving sirolimus-based therapy. The mean duration of the graft was 6 years and of sirolimus treatment was 18 months. Mycophenolate mofetil and steroids were combined with sirolimus for 74 patients. Sirolimus was used as first immunosuppressive therapy for 36 patients, and 44 patients were switched from CIs to sirolimus.

RESULTS

Seventy-nine patients (99%) experienced cutaneous adverse events. Twenty patients (25%) demonstrated serious adverse events, and six patients (7%) stopped sirolimus during the 3 months after the study because of cutaneous events. The most frequent of these were pilosebaceous apparatus involvement, including acne-like eruptions (46%), scalp folliculitis (26%), and hidradenitis suppurativa (12%); edematous complaints, including chronic edemas (55%) and angioedema (15%); mucous membrane disorders, including aphthous ulceration (60%), epistaxis (60%), chronic gingivitis (20%), and chronic fissure of the lips (11%); and last, nail disorders including chronic onychopathy (74%) and periungual infections (16%).

CONCLUSIONS

Skin disorders are frequent in renal transplant recipients receiving sirolimus as a long-term therapy. Despite the usually mild nature of skin events, they are often the reason for stopping sirolimus.

Benefit-Risk Assessment of Sirolimus in Renal Transplantation

Sirolimus (rapamycin) is a macrocyclic lactone isolated from a strain of Streptomyces hygroscopicus that inhibits the mammalian target of rapamycin (mTOR)-mediated signal-transduction pathways, resulting in the arrest of cell cycle of various cell types, including T- and B-lymphocytes. Sirolimus has been demonstrated to prolong graft survival in various animal models of transplantation, ranging from rodents to primates for both heterotopic, as well as orthotopic organ grafting, bone marrow transplantation and islet cell grafting. In human clinical renal transplantation, sirolimus in combination with ciclosporin (cyclosporine) efficiently reduces the incidence of acute allograft rejection. Because of the synergistic effect of sirolimus on ciclosporin-induced nephrotoxicity, a prolonged combination of the two drugs inevitably leads to progressive irreversible renal allograft damage. Early elimination of calcineurin inhibitor therapy or complete avoidance of the latter by using sirolimus therapy is the optimal strategy for this drug. Prospective randomised phase II and III clinical studies have confirmed this approach, at least for recipients with a low to moderate immunological risk. For patients with a high immunological risk or recipients exposed to delayed graft function, sirolimus might not constitute the best therapeutic choice--despite its ability to enable calcineurin inhibitor sparing in the latter situation--because of its anti-proliferative effects on recovering renal tubular cells. Whether lower doses of sirolimus or a combination with a reduced dose of tacrolimus would be advantageous in these high risk situations remains to be determined. Clinically relevant adverse effects of sirolimus that require a specific therapeutic response or can potentially influence short- and long-term patient morbidity and mortality as well as graft survival include hypercholesterolaemia, hypertriglyceridaemia, infectious and non-infectious pneumonia, anaemia, lymphocele formation and impaired wound healing. These drug-related adverse effects are important determinants in the choice of a tailor-made immunosuppressive drug regimen that complies with the individual patient risk profile. Equally important in the latter decision is the lack of severe intrinsic nephrotoxicity associated with sirolimus and its advantageous effects on arterial hypertension, post-transplantation diabetes mellitus and esthetic changes induced by calcineurin inhibitors. Mild and transient thrombocytopenia, leukopenia, gastrointestinal adverse effects and mucosal ulcerations are all minor complications of sirolimus therapy that have less impact on the decision for choosing this drug as the basis for tailor-made immunosuppressive therapy. It is clear that sirolimus has gained a proper place in the present-day immunosuppressive armament used in renal transplantation and will contribute to the development of a tailor-made immunosuppressive therapy aimed at fulfilling the requirements outlined by the individual patient profile.

Investigation of Pediatric Renal Transplant Recipients with Heavy Proteinuria after Sirolimus Rescue

BACKGROUND

Little is known about the incidence and evolution of proteinuria as a complication of sirolimus rescue in children. This study describes pediatric renal transplant (Tx) recipients who were treated with sirolimus and who developed heavy proteinuria. Risk factors for the development of proteinuria and its time course are explored.

METHODS

Data at various time points after sirolimus introduction were abstracted from the records of children treated at the author's center. The repeated measures general linear model and the Student's paired t test were used to analyze changes in laboratory values over time.

RESULTS

Of the 13 children on sirolimus, 12 developed heavy proteinuria after a mean interval of 1 month. The mean urine protein (Up)-to-creatinine (c) ratio increased from 1.1 to a peak value of 3.9 (P=0.003) at 4.6 months after the start of sirolimus. Although not statistically significant, children on no calcineurin inhibitor (CNI) had a greater increase in the Up/c than those on low-dose CNI. At last follow-up, with the use of angiotensin receptor blockers (ARB), the Up/c declined to 2.2. No predictors could be identified for the development of proteinuria.

CONCLUSIONS

Heavy proteinuria is common after the use of sirolimus as rescue therapy in children with renal Tx. Whether this is attributable to a toxic effect of the sirolimus itself or to lower CNI exposure is uncertain. Early detection of proteinuria is important to enable prompt intervention. Most children have a reduction in their Up/c with the use of ARB and can therefore be continued on sirolimus.

Immunosuppressants and skin cancer in transplant patients: focus on rapamycin

BACKGROUND

The responsibility of immunosuppressants for the increased risk of skin cancers in organ transplant recipients is widely recognized. Discerning the role of each drug is complicated owing to the fact that most patients generally have combinations of several medications.

OBJECTIVE

This article will discuss the role of the main immunosuppressants in the pathogenesis of skin cancers.

METHODS

This work consists of a review of the most significant publications.

RESULTS

Experimental and clinical studies suggest that corticosteroids, azathioprine, cyclosporine (CsA), and tacrolimus increase the incidence of skin cancer. Each drug may act through two different mechanisms including the impairment of the systemic immunosurveillance and a direct oncogenic effect. CsA was shown to be oncogenic independently of its immunosuppressive effect. By contrast, several works on mice have found that rapamycin inhibits tumor growth while being immunosuppressive. Furthermore, rapamycin was shown to inhibit several UV-induced mechanisms involved in skin carcinogenesis. Preliminary clinical studies have reported a lower incidence of skin malignancy in patients treated with rapamycin compared to CsA from the time of transplantation.

CONCLUSION

New immunosuppressive strategies for transplant patients with skin cancer are not only based on minimizing immunosuppression. Data suggest that rapamycin could have a protective effect against skin cancer. Further studies are required to assess accurately the efficacy and tolerance of rapamycin in these patients.

Sirolimus-induced angioedema

Sirolimus (SRL) is a macrolide immunosuppressant that has gained widespread use in organ transplantation. Its full spectrum of side-effects is yet to be defined. We describe herein three cases of SRL-induced angioedema (AE) in African-American (AA) primary renal allograft recipients who received SRL in combination with mycophenolate mofetil and steroids. In two cases, AE manifested after SRL was restarted after a period of discontinuation. The third case presented upon initial exposure to the drug. None of the patients was receiving any drug that has been previously associated with AE. Complete resolution occurred only after SRL was withdrawn. AE has not recurred in any of the patients during a follow-up period of up to 21 months. We conclude that AE is a previously unrecognized adverse event associated with SRL use. Close monitoring for this side-effect, especially in AA patients, is warranted.

LYMPHEDEMA ASSOCIATED WITH SIROLIMUS IN RENAL TRANSPLANT RECIPIENTS1

Lymphoceles are common in renal transplant recipients who receive sirolimus (SRL). However, a recent MEDLINE search revealed no reports of lymphedema related to SRL. We describe three cases of lymphedema that resolved or improved on discontinuation of SRL. No other likely causes of lymphedema were discovered. Recognizing the association may lead to early discontinuation of SRL, which may prevent permanent disfigurement. It may also prevent unnecessary investigations. The mechanisms of this phenomenon are not clear. We hypothesize that increased lymph flow along with disrupted lymphatics in the affected extremities may explain this complication of SRL. Further studies are necessary to confirm our findings.

Ten years of sirolimus therapy in orthotopic liver transplant recipients

BACKGROUND

Sirolimus therapy has been used in orthotopic liver transplant (OLT) recipients diagnosed with a variety of diseases; chronic graft rejection (CR), calcineurin associated renal toxicity, preemptive immune suppression, calcineurin related neurotoxicity, preemptive therapy in transplant recipients with history of hepatocellular carcinoma, and steroid resistant allograft rejection.

METHODS

A search for the medical literature and experiences involving sirolimus was done.

RESULTS

Several animal and human reports evaluating the use sirolimus in liver transplant recipients are found and discussed.

CONCLUSION

Sirolimus has been used for multitude of indications, primarily based on anecdotal experiences. However, reports of sirolimus related side effects have decreased the transplant communities' enthusiasm towards promoting this agent as a safe immune suppression agent.