Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0033377 (prolapse)
 11,717 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The likelihood of coexistence in the same patient of myasthenia gravis and myotonic dystrophy has been estimated at 1 in 40 million. The case of a patient in whom both diagnoses were made is reported here. A 13-year-old girl was diagnosed with myasthenia gravis because of weakness, fluctuating fatigability, and mild difficulty with chewing and swallowing. She had ptosis, with weakness predominantly of her face, arms, and neck. Serum antibodies against acetylcholine receptors were 9.9 nmol/L. She was started on pyridostigmine, with significant clinical improvement, reassuming normal daily activities. Two years later, generalized weakness reappeared and reappraisal of her symptomatology disclosed tongue percussion and hand action myotonia. Molecular genetic analysis disclosed 550 repeats of cytosine-thymidine-guanosine triplets on the DMPK gene. Undiagnosed relatives had expansions ranging from 110 to 1000 repeats. Myotonic dystrophy is considered the most common muscular dystrophy, with highly variable clinical manifestations; mildly affected individuals may escape clinical detection. Myasthenia gravis has an estimated prevalence of 15 per 100,000. No studies on the epidemiology of these diseases have been done in Chile. Although both diseases have specific clinical and laboratory presentations, they share some features in the mode of presentation that may generate difficulty in diagnosis of both entities in the same patient.
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PMID:Myotonic dystrophy in a female with myasthenia gravis. 1756 May 8

Myotonic dystrophy type 1 (DM1) is an autosomal-dominant multisystemic disorder that may rarely be associated with benign and malignant neoplasms. Cases of both thymoma and myasthenia gravis in association with DM1 are extremely rare. A literature review revealed only three prior reports. We present a 51-year-old man with a family history of DM1 and fluctuating diplopia and ptosis, who was found to have acetylcholine receptor-binding antibodies, thymoma, and a clinical presentation compatible with ocular myasthenia gravis as well as positive genetic testing for DM1. Needle electromyographic (EMG) study demonstrated diffuse runs of myotonic discharges in multiple muscles, consistent with the diagnosis of DM1. Single-fiber EMG showed both increased jitter and blocking. Due to somatic instability, which has been shown previously in DM1, the myotonin protein kinase (DMPK) gene appears to act as a tumor suppressor. Therefore, abnormal CTG repeat expansions in the gene could lead to the development of thymoma and myasthenia gravis.
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PMID:Myotonic dystrophy type 1 coexisting with myasthenia gravis and thymoma. 1856 24