ABOUT CYSTINOSIS
What
is Cystinosis?
Cystinosis is a rare
metabolic disease that affects approximately 500 people in
the United States
(mostly children),and about 2,000 people worldwide. This
disease causes the amino acid “cystine”
to accumulate in the cells of the body. Over time, the
cystine damages various organs including the kidneys, liver,
muscles, white blood cells, eyes, and central nervous
system. Other complications
include muscle wasting, growth loss, difficulty swallowing,
and developmental delays.
Termed an
“orphan disease,” Cystinosis is a disorder which has not been
“adopted” by the pharmaceutical industry because it provides
little financial
incentive for the private sector to make
and market new medications to treat it or prevent it.
Symptoms
There are three clinical forms of
Cystinosis: Infantile (nephropathic) Cystinosis, late-onset
Cystinosis,
and benign Cystinosis. Infantile Cystinosis is the most severe
and the most common type of Cystinosis. Children with Infantile
Nephropathic Cystinosis generally appear normal at and during
the first 9-10 months of life. By one year of age, symptoms
occur including excessive thirst and urination, failure to
thrive, growth retardation, metabolic acidosis and other
chemical and renal tubular abnormalities. Children often appear
pale and thin and have short stature. The abnormally high loss of phosphorous in the urine leads
to rickets. After one year of age, cystine crystals appear in
the
cornea and cause a severe sensitivity to light (photophobia).
Children with Cystinosis also have an increased level of cystine in their white blood cells. In time,
patients can develop problems such as hypothyroidism, severe
muscle weakness and central nervous system complications. These
children
have normal intelligence, but have an unusual defect in
short-term visual memory. Many have poor
GI motility. Cystagon TM causes hyper secretion
of gastric acid, resulting in gastric distress.
Treatment
Without specific
treatment, children with Cystinosis progress to end-stage
kidney failure by an average age of nine years. In the past,
this meant death.Now these patients can receive kidney
dialysis or transplantation. However, even with successful
treatment, these children can go on to develop abnormalities in other organs and often experience muscle
wasting, growth loss, difficulty swallowing, and
developmental delays.
The only
treatment for Cystinosis is cysteamine. It is the only drug that
slows the progression of the
disease by removing the cystine from the cells. In 1994, the new
product Cystagon TM was made available in capsule form however it has a very bad taste and
must be taken every six hours, every
day, without fail. Although this has led to a much better future
for children and young adults with
Cystinosis, Cystagon TM is very hard on their bodies
and is not a cure.
Informational Video
about Cystinosis
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