Immunosuppressive therapy tacrolimus

Sirolimus is currently the only FDA-approved ToR inhibitor. One of its derivatives, everolimus, is in phase III clinical trials and has been approved for use in some European countries.30 Sirolimus is a macrolide antibiotic that has no effect on cal-cineurin phosphatase.11,31,32 Sirolimus inhibits T cell activation and proliferation by binding to and inhibiting the activation of the mammalian ToR, which suppresses cellular response to IL-2 and other cytokines (i.e., IL-4 and IL-15J.11,31 Studies have shown that sirolimus may be used safely and effectively with either cyclosporine or tacrolimus as a replacement for either azathioprine or mycophenolate mofetil.33 However, when using both sirolimus and cyclosporine as part of a patient s immunosuppressant therapy, because of a drug interaction between the two resulting in a marked increase in sirolimus concentrations, it is recommended to separate the sirolimus and cyclosporine doses by at least 4 hours. Sirolimus also can be used as an alternative agent for patients who do not tolerate calcineurin inhibitors due to nephrotoxicity or other adverse events.34... 

Although tacrolimus therapy is associated with increasing blood pressure, studies have found that tacrolimus has less dramatic effects on GFR and RBF than cyclosporine. In some clinical trials, tacrolimus caused less severe HTN and required significantly fewer antihypertensive medications at both 24 and 60 months after transplantation than cyclosporine.61-63 Thus conversion from cyclosporine-based immunosuppression to tacrolimus-based immunosuppression may be one way to minimize blood pressure increases in transplant recipients. Conversion to sirolimus also may be an alternative to the calcineurin inhibitors in patients with difficult-to-treat HTN because sirolimus therapy is less associated with increased blood pressure. Additionally, withdrawal or tapering of steroid therapy may be an effective strategy for lowering blood pressure. 

The expression level of intestinal MDR1 mRNA has been utilized to the personalized immunosuppressant therapy with tacrolimus in cases of living-donor liver transplantation (LDLT) [84], Tacrolimus shows wide... 

Increased susceptibility to infection and the possible development of lymphoma may result from immunosuppression. Only physicians experienced in immunosuppressive therapy and management of renal transplant patients should use sirolimus. Manage patients receiving the drug in facilities equipped and staffed with adequate laboratory and supportive medical resources. The physician responsible for maintenance therapy should have complete information needed for the follow-up of the patient. Liver transplantation-excess mortality, graft loss, and hepatic artery thrombosis (HAT) The use of sirolimus in combination with tacrolimus was associated with excess mortality and graft loss in a study in de novo liver transplant recipients. Many of these patients had evidence of infection at or near the time of death. 

Echinacea (Echinacea purpurea) Uses immune system stimulant prevention/Rx of colds, flu as supportive th apy for colds chronic infxns of the resp tract lower urinary tract Action Stimulates phagocytosis cytokine production T resp cellular activity topically exerts anesthetic, antimicrobial, anti-inflammatory effects Efficacy Not established may X severity duration of URI Available forms Caps w/ powdered herb equivalent to 300-500 mg, PO, tid pressed juice 6-9 mL, PO, once/d tine 2-4 mL, PO, tid (1 5 dilution) tea 2 tsp (4 g) of powdered herb in 1 cup of boiling water Noles/SE Fever, taste p -version, urticaria, angioedema Contra w/ autoimmune Dz, collagen Dz, progressive systemic Dz (TB, MS, collagen-vascular disorders), HIV, leukemia, may interfere w/ immunosuppressive therapy Interactions t Risk of disulfiram-like reaction W/ disulfiram, metronidazole T risk of exacerbation of HIV or AIDS W/ chinacea amprenavir, other protease inhibitors X effects OF azathioprine, basiliximab, corticosteroids, cyclosporine, daclizumab, econazole vag cream, muromonab-CD3, mycophenolate, prednisone, tacrolimus EMS Possible immunosuppression... 

Immunosuppressive therapy is utilized in chronic severe asthma, where cyclosporine is often effective and sirolimus is another alternative. Omalizumab (anti-IgE antibody) has recently been approved for the treatment of severe asthma (see previous section). Tacrolimus is currently under clinical investigation for the management of autoimmune chronic active hepatitis and of multiple sclerosis, where IFN-3 has a definitive role. 

Treatment of acute CVHD is often unsuccessful and the resulting complications can be fatal. Patients undergoing allogeneic HSCT are given prophylactic immunosuppressive therapy which inhibits T-cell activation and/or proliferation. The most commonly used CVHD prophylaxis regimens are cyclosporine or tacrolimus and methotrexate. 

If no functional impairment is present, patients with fimited disease are not treated with systemic therapy. A variety of topical preparations may be used in patients with skin-only disease, snch as clo-betasol, tacrolimus, and pimecrofimus. Many patients with extensive chronic GVHD, if left untreated, will die of infections or become disabled. The long-term survival rate is worse in certain snbgronps of patients, such as patients with extensive skin involvement, thrombocytopenia, progressive onset of chronic GVHD, and those who fail to respond to immunosuppressive therapy. 

Infection risk Fatal Pneumocystis jirovecii pneumonia complicated immunosuppressive therapy in two patients with steroid-refractory ulcerative colitis taking steroids and tacrolimus [146" ]. Despite immediate therapy with high-dose co-trimoxazole and broad-spectrum antibiotics, both patients died with progressive respiratory failure. 

Cyclosporine and tacrolimus are calcineurin inhibitors that are administered as part of immunosuppressive regimens in kidney, liver, heart, lung, and bone marrow transplant recipients. In addition, they are used in autoimmune disorders such as psoriasis and multiple sclerosis. The pathophysiologic mechanism for ARF is renal vascular vasoconstriction.41 It often occurs within the first 6 to 12 months of treatment, and can be reversible with dose reduction or drug discontinuation. Risk factors include high dose, elevated trough blood concentrations, increased age, and concomitant therapy with other nephrotoxic drugs.41 Cyclosporine and tacrolimus are extensively metabolized by... 

FIGURE 52-2. Center-specific protocols may use RATG, an IL-2RA, or no induction therapy. In any situation, patients receive IV methylprednisolone prior to, during, or immediately following the transplant operation. The patient then will begin the maintenance immunosuppressive regimen. The center-specific protocol will specify which calcineurin inhibitor (cyclosporine or tacrolimus) is used in combination with mycophenolate mofetil or sirolimus with or without steroids. Patients then are monitored for signs and symptoms of rejection. 

Pimecrolimus (SDZ ASM 981, Elidel) is another recently approved macrolide immunosuppressant that acts by inhibiting calcineurin and blocking the release of proinflammatory cytokines from T lymphocytes. The parent compound, ascomycin, was originally isolated from Streptomyces hygroscopicus var ascomyceticus. Like tacrolimus, pimecrolimus is approved for the topical treatment of moderate to severe atopic dermatitis that is refractory to other therapies. Transient local irritation is a common side effect. 

Tacrolimus, an immunosuppressant that inhibits T-cell activation, is a useful alternative in severe recalcitrant psoriasis. Although it is not FDA approved for this indication, patients have received oral doses of 0.05 mg/kg daily, with increases up to 0.15 mg/kg daily, depending on results. Adverse effects include diarrhea, nausea, paresthesias, hypertension, tremor, and insomnia. Methotrexate, an antimetabolite, is indicated for moderate to severe psoriasis. It is particularly beneficial for psoriatic arthritis. It is also indicated for patients refractory to topical or UV therapy. Methotrexate can he administered orally, subcutaneously, or intramuscularly. The starting dose is 7.5 to 15 mg per week, increased incrementally by 2.5 mg every 2 to 4 weeks until response maximal doses are approximately 25 mg/wk. Adverse effects include nausea, vomiting, mucosal ulceration, stomatitis, malaise, headache, macrocytic anemia, and hepatic and pulmonary toxicity. Nausea and macrocytic anemia can be ameliorated by giving oral fohc acid 1 to 5 mg/day. Methotrexate should be avoided in patients with active infections and in those with liver disease. It is contraindicated in pregnancy because it is teratogenic. 

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