Kennedy disease: Difference between revisions
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{{SK}} X-linked spinal-bulbar muscular atrophy; SBMA; KD; bulbospinal muscular atrophy | {{SK}} X-linked spinal-bulbar muscular atrophy; SBMA; KD; bulbospinal muscular atrophy | ||
==Signs and symptoms== | ==Signs and symptoms== | ||
Revision as of 18:39, 19 September 2012
| Kennedy disease | |
| ICD-9 | 335.1 |
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| OMIM | 313200 |
| DiseasesDB | 7144 |
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Kennedy disease Microchapters |
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Diagnosis |
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Treatment |
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Case Studies |
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Kennedy disease On the Web |
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American Roentgen Ray Society Images of Kennedy disease |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Synonyms and keywords: X-linked spinal-bulbar muscular atrophy; SBMA; KD; bulbospinal muscular atrophy
Signs and symptoms
Ages of onset and severity of manifestations in affected males vary from adolescence to old age, but most commonly develop in middle adult life. The latest onset was described in a male of 84 years of age. KD does not usually compromise longevity. The syndrome has neuromuscular and endocrine manifestations:
Neuromuscular
Early signs often include weakness of tongue and mouth muscles, fasciculations, and gradually increasing weakness of limb muscles with muscle wasting. In some cases, premature muscle fatigue begins in adolescence. Neuromuscular management is supportive, and the disease progresses very slowly and often does not lead to extreme disability.
Neurological:
- Bulbar Signs The Bulbar muscles are those supplied by the motor nerves coming off the brain stem which control breathing, swallowing, talking and other functions of the throat. Bulbar signs are problems with these functions.
- Dysphagia Trouble swallowing. (One of the Bulbar signs.)
- Intention Tremor Hand tremors when trying to do something.
- Normal Babinski Normal plantar response, i.e., when the bottom of the foot is scraped, the toes bend down. An abnormal response would be an upward bendings of the toes indicating a problem in the brain itself.
- Lower Motor Neuropathy The lower motor nerves are those that run from the spinal cord to the muscles that they stimulate to move. Loss of that nerve leads to weakness and wasting of the muscle.
- Primary Sensory Neuropathy Numbness over certain areas. Loss of sensation.
- Decreased or Absent Deep Tendon Reflexes. (When a doctor taps the knee with his hammer and nothing happens.)
Muscular:
- Fasciculations Twitching of small muscles without purposeful movement that can be seen through the skin.
- Cramps Large muscle spasms.
- Postural Tremor Shaky muscles with certain positions.
- Muscular Atrophy Wasting and shrinkage of muscles that occurs when the lower motor nerve does not stimulate the muscle adequately.
- Hypertrophied Calves Calf muscles that become thicker because of cramps.
Thoracic:
- Gynecomastia (breast enlargement).
Endrocrine
- Androgen Deficiency Loss of masculinizing effect.
- Estrogen Excess More of an apparent estrogen effect because of the lost of masulinizing effect.
Genito-Urinary:
- Impotence Erectile dysfunction
- Reduced Fertility Low sperm count
- Testicular Atrophy Testicles become smaller and of less functional.
Miscellaneous Characteristics:
- Late Apparent Onset Usually show symptoms late 30's and after
- Slow Progression Near-normal lifespan
- Asymmetry of Clinical Signs Muscles of one side may be more affected than the same muscles on the other side.
Homozygous females
Homozygous females, both of whose X chromosomes have a mutation leading to CAG expansion of the AR gene, have been reported to show only mild symptoms of muscle cramps and twitching. No endocrinopathy has been described.