Comprehensive Nursing Pharmacology Q 149
Nurse Corrine may expect to administer azathioprine (Imuran) to a transplant client in which of the following conditions?
A. Prevention of chronic rejection.
B. Prevention of acute rejection.
C. Management of chronic rejection.
D. Treatment of acute rejection.
Correct Answer: B. Prevention of acute rejection
Azathioprine inhibits humoral and cellular immunity during the early stages of lymphoid differentiation and is useful in preventing the onset of acute rejection. Azathioprine (AZA) is approved by the Food and Drug Administration (FDA) for symptomatic treatment of active rheumatoid arthritis. It also has approval as adjunctive therapy for the prevention of kidney transplant rejection.
Option A: Azathioprine is a purine analog that converts to its active metabolites, mercaptopurine (6-MP), and thioguanine (6-TGN) by the action of hypoxanthine-guanine phosphoribosyltransferase (HPRT) and thiopurine methyltransferase (TPMT) enzymes. It then inhibits purine synthesis.
Option C: Its metabolites are incorporated into the replicating DNA and halt division. AZA metabolites may also mediate most of its immunosuppressive and toxic effects. AZA is absorbed rapidly through the GI system and does not penetrate the blood-brain barrier. It undergoes metabolism in the liver and excretion is via the kidneys, which increases its toxicity in renal failure.
Option D: AZA used off-label for the treatment of inflammatory bowel disease, Churg-Strauss syndrome, autoimmune hepatitis (for maintenance treatment along with steroids), chronic ITP (second-line agent), lupus nephritis, connective tissue disease-associated ILD, multiple sclerosis, severe myasthenia gravis, recurrent pericarditis, psoriasis, non-infectious uveitis, relapsing polychondritis, dermatomyositis/polymyositis, erythema multiforme, severe and refractory atopic dermatitis, chronic actinic dermatitis, pyoderma gangrenosum, Behcet disease, cutaneous vasculitis, pityriasis rubra pilaris, lichen planus, bullous pemphigoid, and pemphigus vulgaris.