Myasthenia gravis in the context of "Weakness"

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⭐ Core Definition: Myasthenia gravis

Myasthenia gravis (MG) is a long-term neuromuscular junction disease that leads to varying degrees of skeletal muscle weakness. The most commonly affected muscles are those of the eyes, face, and swallowing. It can result in double vision, drooping eyelids, and difficulties in talking and walking. Onset can be sudden. Those affected often have a large thymus or develop a thymoma.

Myasthenia gravis is an autoimmune disease of the neuromuscular junction which results from antibodies that block or destroy nicotinic acetylcholine receptors (AChR) at the junction between the nerve and muscle. This prevents nerve impulses from triggering muscle contractions. Most cases are due to immunoglobulin G1 (IgG1) and IgG3 antibodies that attack AChR in the postsynaptic membrane, causing complement-mediated damage and muscle weakness. Rarely, an inherited genetic defect in the neuromuscular junction results in a similar condition known as congenital myasthenia. Babies of mothers with myasthenia may have symptoms during their first few months of life, known as neonatal myasthenia or more specifically transient neonatal myasthenia gravis. Diagnosis can be supported by blood tests for specific antibodies, the edrophonium test, electromyography (EMG), or a nerve conduction study.

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Myasthenia gravis in the context of Strabismus

Strabismus is an eye disorder in which the eyes do not properly align with each other when looking at an object. The eye that is pointed at an object can alternate. The condition may be present occasionally or constantly. If present during a large part of childhood, it may result in amblyopia ("lazy eyes") and loss of depth perception. If onset is during adulthood, it is more likely to result in double vision.

Strabismus can occur out of muscle dysfunction (e.g., myasthenia gravis), farsightedness, problems in the brain, trauma, or infections. Risk factors include premature birth, cerebral palsy, and a family history of the condition. Types include esotropia, where the eyes are crossed ("cross eyed"); exotropia, where the eyes diverge ("lazy eyed" or "wall eyed"); and hypertropia or hypotropia, where they are vertically misaligned. They can also be classified by whether the problem is present in all directions a person looks (comitant) or varies by direction (incomitant). Another condition that produces similar symptoms is a cranial nerve disease. Diagnosis may be made by observing the light reflecting from the person's eyes and finding that it is not centered on the pupil. This is known as the Hirschberg reflex test.

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Myasthenia gravis in the context of Asthenia

Weakness is a symptom of many different medical conditions. The causes are many and can be divided into conditions that have true or perceived muscle weakness. True muscle weakness is a primary symptom of a variety of skeletal muscle diseases, including muscular dystrophy and inflammatory myopathy. It occurs in neuromuscular junction disorders, such as myasthenia gravis.

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Myasthenia gravis in the context of Muscular weakness

Muscle weakness is a lack of muscle strength. Its causes are many and can be divided into conditions that have either true or perceived muscle weakness. True muscle weakness is a primary symptom of a variety of skeletal muscle diseases, including muscular dystrophy and inflammatory myopathy. It occurs in neuromuscular junction disorders, such as myasthenia gravis. Muscle weakness can also be caused by low levels of potassium and other electrolytes within muscle cells. It can be temporary or long-lasting (from seconds or minutes to months or years). The term myasthenia is from my- from Greek μυο meaning "muscle" + -asthenia ἀσθένεια meaning "weakness".

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Myasthenia gravis in the context of Ciprofloxacin

Ciprofloxacin is a fluoroquinolone antibiotic used to treat a number of bacterial infections. This includes bone and joint infections, intra-abdominal infections, certain types of infectious diarrhea, respiratory tract infections, skin infections, typhoid fever, and urinary tract infections, among others. For some infections it is used in addition to other antibiotics. It can be taken by mouth, as eye drops, as ear drops, or intravenously.

Common side effects include nausea, vomiting, and diarrhea. Severe side effects include tendon rupture, hallucinations, and nerve damage. In people with myasthenia gravis, there is worsening muscle weakness. Rates of side effects appear to be higher than some groups of antibiotics such as cephalosporins but lower than others such as clindamycin. Studies in other animals raise concerns regarding use in pregnancy. No problems were identified, however, in the children of a small number of women who took the medication. It appears to be safe during breastfeeding. It is a second-generation fluoroquinolone with a broad spectrum of activity that usually results in the death of the bacteria.

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Myasthenia gravis in the context of Moxifloxacin

Moxifloxacin is an antibiotic, used to treat bacterial infections, including pneumonia, conjunctivitis, endocarditis, tuberculosis, and sinusitis. It can be given by mouth, by injection into a vein, and as an eye drop.

Common side effects include diarrhea, dizziness, and headache. Severe side effects may include spontaneous tendon ruptures, nerve damage, and worsening of myasthenia gravis. Safety of use in pregnancy and breastfeeding is unclear. Moxifloxacin is in the fluoroquinolone family of medications. It usually kills bacteria by blocking their ability to duplicate DNA.

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