Myasthenia gravis (MG)
Myasthenia gravis adalah gangguan autoimun dicirikan dengan kelemahan otot. Penyakit ini cenderung untuk menyerang wanita daripada lelaki (nisbah 3:02), ia biasanya menyerang wanita antara umur 20 dan 40 tahun. Selepas kira-kira umur 50 tahun, kedua-dua jantina cenderung untuk sama-sama mendapat penyakit ini. Walaupun penyakit ini progresif dan boleh menjejaskan mana-mana kumpulan otot, pesakit Myasthenia gravis mempunyai kelemahan pada muka, lidah, dan leher. Kelemahan otot ini mungkin menyebabkan penglihatan berganda atau kelopak mata jatuh, kesukaran mengunyah, menelan, dan bercakap merupakan ciri-ciri penyakit Myasthenia gravis.
Kajian kes Myasthenia gravis (MG)
JP, seorang perempuan berumur 59 tahun mendapat 17 rawatan pada 26 Mac 2010, beliau telah di diagnosis dengan penyakit MG selepas ujian awal pada umur 40 .
Gejala termasuk:
• kelemahan otot pada seluruh badan
• kelopak mata jatuh di sebelah kanan
• muka kendur di sebelah kanan
• Kekurangan ekspresi muka di sebelah kanan
• Kelemahan otot tangan
• keletihan melampau pada waktu siang
• gangguan tidur pada waktu malam
• masalah keseimbangan badan
JP mengalami kelemahan otot yang teruk, kelopak mata kanan jatuh, muka kendur sebelah kanan , dan inkontinens segera. Dia tidak dapat tidur lena pada waktu malam, tetapi mengantuk sepanjang hari. Dia mudah lesu dan mempunyai masalah dengan keseimbangan badan serta kerap jatuh.
Diagnosis
Doktor mungkin mengesyaki beliau mengidap penyakit Myasthenia gravis berdasarkan simptom-simptom beliau.
Plasmapheresis.
Plasmapheresis ialah proses pemisahan plasma yang mana mengandungi autoantibodies dari sel darah merah yang kemudiannya dikembalikan semula kedalam badan. Rawatan ini mengurangkan gejala sementara dan amat penting sebelum untuk pembedahan timus dilakukan. Kesan-kesan sampingan yang paling biasa adalah hypotension (tekanan darah rendah). Beberapa kajian menunjukkan bahawa kadar jangkitan dan kematian akibat plasmapheresis adalah rendah, dan semua pesakit mempunyai manfaat daripada prosedur ujian tersebut.
Plasmaferesis
Plasmaferesis merupakan kaedah pengasingan plasma dari ‘whole blood’ dan sel dikembalikan semula kepada pesakit.
Pertukaran plasma
Dos: 5 pertukaran selama 9 hingga 10 hari
• Petunjuk
· Pesakit MG akut
· Pesakit Pra-thymectomy dengan sistem pernafasan
· TIDAK untuk rawatan jangka panjang
• Kelebihan
· Tindakan yang singkat (3 hingga 10 hari)
· Lebih berkesan dalam krisis daripada globulin imun manusia
• Kelemahan
· Memerlukan peralatan khusus & kakitangan
· Komplikasi lebih kerap pada warga tua
· Kos yang tinggi
· Manfaat hanya jangka pendek (minggu)
· kesan sampingan Lebih daripada globulin imun manusia
Rawatan dengan ubatan
• Pyridostigmine (Mestinon)
§ 60 mg tid to 120 mg q3h
§ 90 to 180 mg qhs
Prednisone
o 
Begin at 20 mg qd
o 
Begin at 5 mg qd
• Azathioprine (Imuran)
• Cyclosporine A
Komplikasi terapi plasmaferesis
Walaupun plasmapheresis berguna dalam keadaan tertentu, seperti mana-mana terapi lain, terdapat risiko dan komplikasi. Pemasukan kateter intravena yang agak besar boleh membawa kepada pendarahan, tusukan paru-paru (bergantung pada tempat kemasukan kateter), dan jika kateter dibiarkan terlalu lama ia boleh terinfeksi. Selain daripada meletakkan kateter, prosedurnya mempunyai komplikasi. Apabila darah pesakit berada di luar badan melalui mesin plasmapheresis, darah tersebut mempunyai potensi untuk beku. Untuk mengurangkan kecenderungan ini, sitrat dimasukan semasa aliran darah berjalan melalui litar. Citrate mengikat kepada kalsium dalam darah, kalsium penting untuk darah membeku. Citrate adalah sangat berkesan dalam menghalang pembekuan darah.
Komplikasi lain
• hypotension
• Potensi untuk produk darah, risiko reaksi transfusi atau pemindahan penyakit
• Penindasan sistem imun pesakit
• Pendarahan atau hematoma daripada penempatan jarum
Akhir rawatan
LAMPIRAN
Myasthenia Gravis
Myasthenia gravis is an autoimmune disorder characterized by muscle weakness. The disease tends to strike women more often than men (by a ratio of about 3:2), usually affecting women between the ages of 20 and 40 (Beers MH 2005). After about age 50, both sexes tend to be equally affected (Phillips LH 1994). Although the disease is progressive and can affect any muscle groups, people afflicted with myasthenia gravis often have weakness of face, tongue, and neck. This muscle weakness might result in double vision or drooping eyelids, which along with difficulty chewing, swallowing, and talking, are characteristic symptoms of myasthenia gravis.
Myasthenia Gravis (MG) Case Study
JP, a 59 year old female has had 17 treatments as of March 26, 2010, she was diagnosed with MG after initial testing in her 40's .
Symptoms included:
· Muscle weakness over whole body, increasing with use
· Drooping eyelid on right side
· Sagging face on right side
· Lack of facial expression on right side
· Weakness of the hand muscle
· Extreme tiredness in daytime
· Sleep disturbance at night
· Equilibrium/Balance problems
JP experienced severe muscle weakness, drooping of right eyelid, sagging of right side of face, and urgency incontinence. She didn't sleep well at night, but was sleepy during the day requiring frequent naps lasting more than one hour at a time. She was lethargic and had problems with balance, falling frequently.
Diagnosis
Physicians may suspect she has myasthenia gravis with her characteristic weakness.
Plasmapheresis.
Plasmapheresis separates plasma, which contains the autoantibodies, from red blood cells, which are then returned to the body. This treatment improves symptoms temporarily and is especially valuable in preparation for surgical removal of the thymus. The most common side effects are reversible hypotension (low blood pressure) and mild tremor. Several studies indicate that infection and mortality rates due to plasmapheresis were negligible, and all patients had immediate benefit from the procedure.
Plasma Exchange
- Dose: 5 exchanges over 9 to 10 days
- Indications
- Acutely ill MG patient
- Pre-thymectomy in patient with respiratory or bulbar involvement
- NOT for long-term treatment
-
- Advantages
- Very short onset of action (3 to 10 days)
- Probably more effective in crisis than human immune globulin
-
- Disadvantages
- Requires specialized equipment & personnel
- Complications more frequent in elderly
- High cost
- Benefit only short-term (weeks)
- More side effects than human immune globulin
-
Treatment with medicine
Pyridostigmine (Mestinon)
- Pills:
- 60 mg tid to 120 mg q3h
-
- Timespan pills:
- 90 to 180 mg qhs
-
- Inpatient: starting
Begin at 20 mg qd
- Outpatient: starting
Begin at 5 mg qd
Azathioprine (Imuran) 
Cyclosporine A 
Complications of plasmapheresis therapy
Though plasmapheresis is helpful in certain medical conditions, like any other therapy, there are potential risks and complications. Insertion of a rather large intravenous catheter can lead to bleeding, lung puncture (depending on the site of catheter insertion), and, if the catheter is left in too long, it can get infected. Aside from placing the catheter, the procedure itself has complications. When patient blood is outside of the body passing through the plasmapheresis machine, the blood has a tendency to clot. To reduce this tendency, in one common protocol[citrate is infused while the blood is running through the circuit. Citrate binds to calcium in the blood, calcium being essential for blood to clot. Citrate is very effective in preventing blood from clotting; however, its use can lead to life-threateningly low calcium levels. This can be detected using the Chvostek's sign or Trousseau's sign. To prevent this complication, calcium is infused intravenously while the patient is undergoing the plasmapheresis; in addition, calcium supplementation by mouth may also be given.
Other complications include:
· Hypotension
· Potential exposure to blood products, with risk of transfusion reactions or transfusion transmitted diseases
· Suppression of the patient's immune system
· Bleeding or hematoma from needle placement
End of treatment:
