Gastrointestinal Tract Disorders
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pylori Infection May
Aggravate GI Injury in Patients Taking Low-dose Aspirin
Doctors commonly prescribe low-dose aspirin for the prevention of heart
disease, but it may also be responsible for some potentially serious
side effects when taken frequently. Among the most common of these are
gastrointestinal erosions and ulcers.
A recent study
in The American Journal of Gastroenterology sought to determine
whether certain people taking low-dose aspirin specifically,
people infected with Helicobacter pylori, a common bacterium
that can cause ulcers are more susceptible to gastrointestinal
erosions and ulcers than people who are not infected with H. pylori.
the University of Texas Southwestern Medical School and Baylor College
of Medicine recruited 61 healthy volunteers between the ages of 18
and 61. Of these, 29 volunteers were infected with H. pylori.
Forty-six of the volunteers were then randomly selected to receive
low-dose aspirin (either 81 mg daily or 325 mg every three days), while
15 received a placebo.
After 46 days
of treatment, an upper GI endoscopy was performed on each subject to
determine the extent of gastrointestinal injury. The researchers did
not detect any injury in the stomach or duodenum (upper intestine)
of the patients taking placebo. In the subjects taking aspirin, those
patients who were infected with H. pylori were significantly
more likely to have gastrointestinal injury than those who were not
infected (50% vs. 16%).
was no difference between the groups in complaints of pain, nausea,
vomiting, indigestion, or heartburn. In addition, the difference in
outcomes between patients taking 81 mg of aspirin daily and 325 mg
every three days was not statistically significant.
The researchers caution that the results of this study may not hold for
older people or those with gastrointestinal diseases such as peptic ulcer
disease, because the volunteers were healthy and aged 61 or younger.
However, this study does suggest eradicating H. pylori infection
may help prevent gastrointestinal erosions and ulcers in patients taking
low-dose aspirin on a long-term basis.
October 2001 Update
Approves Gleevec to Treat Leukemia
myelogenous leukemia (CML), one of four main types of leukemia,
strikes about 5,000 people every year. On average, patients live
3-4 years after receiving a diagnosis of CML. Last week, the
FDA approved Gleevec (imatinib mesylate, also known as STI 571)
as an oral treatment for CML.
Gleevec has been shown to substantially reduce the level of
cancerous cells in the bone marrow and blood of treated patients.
In clinical trials, 90 percent of patients in the first phase
of CML went into remission within the first six months of taking
Gleevec. Of patients in the second phase of CML, 63 percent
went into remission with Gleevec. The drug produced few side
Additional studies need to be done to determine how long the
effects of this drug last, whether patients become resistant
to the drug, and, most importantly, whether Gleevec can actually
extend a patient's life.
Still, the results are promising. Currently, the only cure
for CML is a bone marrow transplant. Even if a patient is lucky
enough to find a marrow donor match, the procedure is successful
less than 2/3 of the time. Interferon, a widely used treatment
for CML, can extend a patient's life for up to two years, but
it has several serious side effects and does not cure the disease.
Gleevec may be used in patients in the early stage of CML who
do not respond to interferon therapy, and in patients in the
later stages of CML.
Most people with CML have a chromosomal abnormality, known
as the Philadelphia chromosome, in which portions of two different
chromosomes are switched. The result is the creation of an
abnormal protein that allows the uncontrolled production of
white blood cells, which can interfere with the function of
other organs in the body. Gleevec blocks a signal sent out
by the abnormal protein, thus blocking the rapid growth of
white blood cells.
The FDA's approval of the drug came after a surprisingly short
months. Most drugs that, like Gleevec, are granted a priority
review, take six months to approve. The approval was based
on three separate studies that involved about 1,000 patients
with CML. The drug has generated enthusiasm in the medical
community because it targets a specific, cancer-causing protein,
without damaging other cells.
Scientists at an American Society of Clinical Oncology meeting
announced earlier this month that Gleevec had also produced
remission in 180 patients with advanced cases of an intestinal
cancer known as gastrointestinal stromal tumor (GIST). Until
now, GIST cancers have been incurable; GIST patients normally
die within one year of receiving their diagnosis.
May 2001 Update
the Side Effects of Prostatectomy vs. Radiation Therapy
Prostate cancer is the most commonly diagnosed non-skin cancer among
men in the United States. When caught early, it is also among the most
treatable. Two of the more aggressive and
of treatment for early-stage prostate cancer are radiation therapy and
surgery (radical prostatectomy) to remove the prostate gland. Although
both options have favorable outcomes, physicians have not reached a consensus
on which therapy is more effective. This means that men who are treated
with either surgery or radiation can usually expect to live for many
more years. The caveat is that they often have to live with the side
effects of their treatment. Deciding on a treatment option, then, becomes
a question of which side effects are more likely with each therapy, and
also which side effects are more tolerable to a particular patient.
A recent analysis of data from the Prostate Cancer Outcomes Study helps
to clarify this issue by comparing the side effects of the two therapies
in men between the ages of 55 and 74, two years after treatment. The
results showed that men in both treatment groups experienced significant
decreases in sexual function. Of the men in the surgery group, 80%
became impotent, compared to 62% of the men in the radiation group.
Age and status of sexual function prior to treatment affected these
outcomes. Twelve percent of the men who underwent surgery experienced
dripping or leaking urine, compared to only 2% of the men who had radiation
therapy. Few men in either group were bothered by bowel problems. Of
the men who were affected, however, radiation patients experienced
more diarrhea, bowel urgency, and painful hemorrhoids (33%, 30%, and
19%, respectively) compared to surgery patients (22%, 16%, and 10%).
Overall, this study showed that men who opt for surgery can expect
to have more urinary and sexual problems, while men who choose radiation
are more likely to suffer from bowel disturbances. A man's age and
initial health are also important factors in the development and duration
of long-term side effects from either treatment. Physicians and their
patients should use this information, as well as a discussion of the
patient's priorities, preferences, and concerns, to help decide which
treatment method is appropriate.
March 2001 Update
and Peanut Allergies
outgrow allergies to milk and eggs, but not to peanuts. In a recent
study, researchers found that the majority of children with peanut
allergies will have adverse reactions to accidental peanut exposure
within five years. In addition, allergic reactions are likely to worsen
over the years.
Researchers followed 83 children who were diagnosed with a peanut
allergy before their 4th birthday. Of these children, 61 had initial
non-life-threatening reactions, while 22 had potentially life-threatening
reactions. After 5.9 years, they found that 50 of the 83 children
had experienced a total of 115 adverse reactions to peanuts.
Most of the reactions increased in severity after the initial reaction.
Of the children with initial non-life-threatening reactions who had
additional reactions, 44% had at least one potentially life-threatening
subsequent reaction. And of the 22 children who had initial life-threatening
reactions followed by additional reactions, 71% had at least one
additional life-threatening reaction.
In 12 of the original 83 children, the initial reaction occurred
after touching, (not eating) peanuts, and they experienced only skin
symptoms. Eight of these 12 had subsequent reactions, and all eight
had at least one occurrence of respiratory or gastrointestinal symptoms.
Children with only skin symptoms had significantly lower serum peanut-specific
antibodies than those with other initial symptoms, but there was
antibody level below which subsequent reactions were only skin-specific.
Most children with peanut allergies accidentally ingest peanuts and
this study showed that allergic reactions are likely to get progressively
worse with each exposure. Children must be educated to avoid peanuts
and foods containing peanuts. In addition, children should always
have access to a self-injectable epinephrine kit that both parents
and children should know how to use if the need arises.
February 2001 Update
Reptiles and Salmonella
1996 and 1998, approximately 16 state health departments reported salmonella
infections in persons who had direct or indirect contact with reptiles
(i.e., lizards, snakes, or turtles) to the Centers for Disease Control
Salmonella infection can result
in severe illness and even death, particularly in infants, young children,
and anyone with a compromised immune system. The CDC issued the following
recommendations to reduce the chances of anyone in your family contracting
this potentially deadly infection from these increasingly popular exotic
- Pet store owners, veterinarians,
and pediatricians should provide information to owners and potential
purchasers of reptiles about the risk of acquiring salmonellosis
- People should always wash
their hands thoroughly with soap and water after handling reptiles
or reptile cages.
- People at increased
risk for infection or serious complications of salmonellosis
(e.g., children younger than age 5 and immunocompromised persons)
should avoid contact with reptiles.
- Pet reptiles should
be kept out of households where children younger than age 5 and
immunocompromised persons live. Families expecting a new child
should remove the pet reptile from the home before the infant
- Pet reptiles should
not be kept in childcare centers.
- Pet reptiles should
not be allowed to roam freely throughout the home or living area.
- Pet reptiles should
be kept out of kitchens and other food-preparation areas to prevent
- Kitchen sinks should
not be used to bathe reptiles or to wash their dishes, cages,
or aquariums. If bathtubs are used for these purposes, they should
be cleaned thoroughly and disinfected with bleach.