KENNEDY DISEASE Causes | Symptoms | Diagnosis | Treatments
What is Kennedy Disease ? Kennedy
disease is
a
rare,
X-linked
slowly
progressive
neuromuscular disorder . Kennedy
disease is typically an adult-onset disease, where symptoms occur mainly between the ages of 20 and 50. The disease is characterized by symptoms such as muscle weakness and cramps in the arms, legs, and facial area, enlarged breasts, and difficulty with speaking and swallowing ( dysphagia) .
Causes of Kennedy Disease Kennedy
disease is an X-linked genetic disorder that occurs primarily in
males. Very rarely, female carriers of the abnormal gene may show symptoms. It is caused by a mutation in a gene that encodes for a protein known as the androgen receptor (AR) and was mapped to band Xq11-q12 on the X chromosome. The
instructions within every gene consist of different arrangements of four basic chemicals (nucleotide bases) called adenine (A), cytosine (C), guanine (G), and thymine (T). Individuals with the disease have an abnormal section in the AR gene, which is due to an excessive number of CAG trinucleotide repetitions in the DNA sequence. An unaffected individual has 10-35 CAG repeats in the AR gene while a person with Kennedy disease has more than 36 CAG repeats in the gene.
Symptoms of Kennedy Disease Affected individuals begin to develop neurological symptoms between 20 to 50 years of age. These early symptoms include: Swallowing Speech Hand
difficulties
difficulties
tremors Shaky muscles when holding certain postures Muscle weakness Muscle wastage
Symptoms continue… Muscle
twitches Muscle cramps and spasms Enlarged calf muscles due to constant cramping Localized areas of numbness Absent
reflexes, such as the foot remaining still when the tendon beneath the kneecap is tapped Enlarged breast tissue Impotence Low sperm count Shrunken
testicles Reduced sex drive
Diagnosis of Kennedy disease Since Kennedy's disease is rare, it can be misdiagnosed. It is sometimes mistaken for the more common motor neuron disease (amyotrophic lateral sclerosis), a progressive nervous system disease characterized by the breaking down of neurones in the spinal cord and brain. Kennedy disease can be diagnosed using a number of tests including: ď ą Blood
test to check for elevated serum creatine kinase (CPK): People
with Kennedy disease usually have a greater than average amount of this particular enzyme circulating in their blood. ď ą Genetic tests using a blood sample: This test can check whether the Kennedy disease gene is present, even if the person is asymptomatic or a carrier. Genetic counseling is important.
Treatments of Kennedy Disease There is no cure for Kennedy disease, because medical science doesn't know how to regenerate muscle neurones. Treatment aims to ease some of the symptoms and can include: Medications to reduce muscle cramps and tremors Plenty of rest and avoidance of exhaustion Healthy, balanced diet Gentle
and regular aerobic exercise
Regular
stretching to help reduce muscle cramping Pain management Speech therapy Occupational Physiotherapy
therapy