Azathioprine myasthenia gravis

Clinical Use. Azathioprine (Imuran) is a cytotoxic agent that is structurally and functionally similar to certain anticancer drugs, such as mercaptopurine.22,30 Azathioprine is primarily used to prevent the rejection of transplanted organs, especially in patients with kidney transplants. Azathioprine may also be used to suppress immune responses in a wide range of other conditions, such as systemic lupus erythematosus, dermatomyositis, inflammatory myopathy, hepatic disease, myasthenia gravis, and ulcerative colitis. As presented in Chapter 16, azathioprine is also used as an antiarthritic disease-modifying agent. 

Azathioprine Imuran Kidney, heart, liver, pancreas Rheumatoid arthritis, inflammatory bowel disease, myasthenia gravis, systemic lupus erythematosus (SLE), others... 

Canalicular cholestasis with portal fibrosis and ductal proliferation has been reported after 24 years of azathioprine in a 57-year-old woman with myasthenia gravis (34). 

Muszkat M, Pappo O, Caraco Y, Haviv YS. Hepatocanalicular cholestasis after 24 years of azathioprine administration for myasthenia gravis. Clin Drug Invest 2000 19 75-8. 

Barthelmes L, Thomas KJ, Seale JR. Prostatic involvement of a testicular lymphoma in a patient with myasthenia gravis on long-term azathioprine. Leuk Lymphoma 2002 43(12) 2425-6. 

Immunosuppressants such as azathioprine are used when other forms of treatment fail to control the progression of myasthenia gravis. 

Azathioprine is indicated in renal homotransplantation (five-year patient survival rate of 35%) in rheumatoid arthritis (for patients with severe, active, and erosive disease not responding to conventional therapies) and in chronic ulcerative colitis, myasthenia gravis, and Behcet s syndrome (adverse effects may offset its limited value). As with other cytotoxic drugs, azathioprine can affect rapidly growing cells, resulting in leukopenia, thrombocytopenia, and gastrointestinal toxicity. In addition, hepatotoxicity (cholestasis) has been reported. Many of the general problems of immunosuppression, such as increased risk of infections, can also occur. 

Infection risk A brain abscess due to Salmonella heidelberg was successfully treated with craniotomy and drainage followed by antibiotic therapy in a 50-year-old woman with myasthenia gravis who had taken azathioprine 200mg/day for more than 10 years [166 ]. 

Soni CR, Kumar G, Bollu PC, Sahota P, Litofsky NS. Salmonella brain abscess in a patient on chronic azathioprine therapy for myasthenia gravis report of an unusual case and review of literature in the postantibiotic era. J Neurovirol 2010 16(1) 83-92. 

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