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Medical
Information
This is some information
on some of the medical conditions that Emily faced:
Diffuse Large B-Cell Lymphomas (DLBCL)
A cancer of
b-cells (lymphocytes) that normally reside in the lymphatic
system.
The word "diffuse" describes the cell pattern. B-cells arise from
the bone marrow and mature or differentiate into many cell types
that tend to migrate to different areas of the body.
What is lymphoma? Briefly, lymphomas result when
damage to DNA occurs to a type of white blood cell
(a lymphocyte) that results in the abnormal production of proteins
that prevents the cells from dying when they should, or causes
sustained rapid cell division. These malignant cells then may
accumulate to form tumors that may enlarge the lymph nodes or spread
to other areas of the lymphatic system, such as the spleen or bone
marrow. Lymphoma cells can also migrate to, or first appear, outside
the lymphatic system. Lymphoma that presents outside the lymphatic
system is called extranodal disease. For details, see What's
Lymphoma & Lymphoma simplified.
Initial presentation: DLBCL typically presents as a
nodal or extranodal (outside the lymphatic system) mass with fast
tumour growth associated with systemic symptoms, such as sweats,
fatigue, and fever. In about 40% of cases, these lymphomas appear in
areas outside lymph nodes, including digestive tract, skin, bone,
thyroid, and testes.
Staging: Staging refers to the how widespread the
disease is. Imaging tests (CT MRI, PET, Gallium) and bone marrow
biopsies are commonly done to estimate this.
Staging
defines how widespread the disease is and the locations of the
disease in the body.
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Hemophagocytic Lymphohistiocytosis:
Hemophagocytic Syndromes and Infection
Hemophagocytic
lymphohistiocytosis (HLH) is a rare and unusual syndrome characterized by
fever, splenomegaly, jaundice, and the pathologic finding of
hemophagocytosis (phagocytosis by macrophages of erythrocytes,
leukocytes, platelets, and their precursors) in bone marrow and
other tissues. HLH may be diagnosed in association with malignant,
genetic, or autoimmune diseases but is also prominently linked with
Epstein-Barr (EBV) virus infection. Hyperproduction of cytokines,
including interferon-g and tumor necrosis factor-a, by EBV-infected
T lymphocytes may play a role in the pathogenesis of HLH.
EBV-associated HLH may mimic T-cell lymphoma and is treated with
cytotoxic chemotherapy, while hemophagocytic syndromes associated
with nonviral pathogens often respond to treatment of the underlying
infection.
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Natural killer cell deficiency
Natural killer (NK) cell deficiency is an
Primary cellualr immune system disorder in which the patient has
low or absent levels of a certain type of white blood cells
called NK cells. The NK cells help the immune system fight
against disease and infection. These cells recognize and
destroy body cells that have become infected with viruses or
cancer. They have pouches, called granules, which are filled
with chemicals that destroy infected cells on contact.
Healthy individuals normally experience
fluctuations in the number of NK cells in the blood. These
cells rapidly increase in response to an infection and then
decrease for five to seven days after the infection.
Patients with NK cell deficiency are born
with low or nonexistent levels of NK cells. As a result,
these patients are vulnerable to infections. Life expectancy
varies among patients, depending on how severe the
deficiency. The condition may lead to fatal infections and
recent studies have suggested patients may have an increased
of developing cancer.
The exact incidence of NK cell deficiency
remains unknown.
Currently, there is no specific treatment for
NK cell deficiency. Instead, treatment focuses on curing
infections associated with the disorder. Treatment of
infections is generally longer in patients with NK cell
deficiency than in the general population because they
respond more slowly.
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Epstein-Barr Virus
Epstein-Barr virus,
frequently referred to as EBV, is a member of the herpesvirus family
and one of the most common human viruses. The virus occurs
worldwide, and most people become infected with EBV sometime during
their lives. In the United States, as many as 95% of adults between
35 and 40 years of age have been infected. Infants become
susceptible to EBV as soon as maternal antibody protection (present
at birth) disappears. Many children become infected with EBV, and
these infections usually cause no symptoms or are indistinguishable
from the other mild, brief illnesses of childhood. In the United
States and in other developed countries, many persons are not
infected with EBV in their childhood years. When infection with EBV
occurs during adolescence or young adulthood, it causes infectious
mononucleosis 35% to 50% of the time.
Symptoms of
infectious mononucleosis are fever, sore throat, and swollen lymph
glands. Sometimes, a swollen spleen or liver involvement may
develop. Heart problems or involvement of the central nervous system
occurs only rarely, and infectious mononucleosis is almost never
fatal. There are no known associations between active EBV infection
and problems during pregnancy, such as miscarriages or birth
defects. Although the symptoms of infectious mononucleosis usually
resolve in 1 or 2 months, EBV remains dormant or latent in a few
cells in the throat and blood for the rest of the person's life.
Periodically, the virus can reactivate and is commonly found in the
saliva of infected persons. This reactivation usually occurs without
symptoms of illness.
EBV also
establishes a lifelong dormant infection in some cells of the body's
immune system. A late event in a very few carriers of this virus is
the emergence of Burkitt's lymphoma and nasopharyngeal carcinoma,
two rare cancers that are not normally found in the United States.
EBV appears to play an important role in these malignancies.
Most individuals
exposed to people with infectious mononucleosis have previously been
infected with EBV and are not at risk for infectious mononucleosis.
In addition, transmission of EBV requires intimate contact with the
saliva (found in the mouth) of an infected person. Transmission of
this virus through the air or blood does not normally occur. The
incubation period, or the time from infection to appearance of
symptoms, ranges from 4 to 6 weeks. Persons with infectious
mononucleosis may be able to spread the infection to others for a
period of weeks. However, no special precautions or isolation
procedures are recommended, since the virus is also found frequently
in the saliva of healthy people. In fact, many healthy people can
carry and spread the virus intermittently for life. These people are
usually the primary reservoir for person-to-person transmission. For
this reason, transmission of the virus is almost impossible to
prevent.
The clinical
diagnosis of infectious mononucleosis is suggested on the basis of
the symptoms of fever, sore throat, swollen lymph glands, and the
age of the patient. Usually, laboratory tests are needed for
confirmation. Serologic results for persons with infectious
mononucleosis include an elevated white blood cell count, an
increased percentage of certain atypical white blood cells, and a
positive reaction to a "mono spot" test.
There is no
specific treatment for infectious mononucleosis,
other than treating the symptoms. No antiviral drugs or vaccines are
available. Some physicians have prescribed a 5-day course of
steroids to control the swelling of the throat and tonsils. The use
of steroids has also been reported to decrease the overall length
and severity of illness, but these reports have not been published.
It is important to
note that symptoms related to infectious mononucleosis caused by EBV
infection seldom last for more than 4 months. When such an illness
lasts more than 6 months, it is frequently called chronic EBV
infection. However, valid laboratory evidence for continued active
EBV infection is seldom found in these patients. The illness should
be investigated further to determine if it meets the criteria for
chronic fatigue syndrome, or CFS. This process includes ruling out
other causes of chronic illness or fatigue
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BK Virus
BK is a member of the
Polyomaviridae family, which are small, nonenveloped viruses with a
closed
circular double-stranded DNA genome. Polyomaviruses are ubiquitous
in nature and can be isolated
from a number of species. BKV and JCV make up the members of the
human polyomaviruses.
BK virus was first isolated in 1971 from the urine of a renal
transplant patient who developed
ureteral stenosis postoperatively. The virus was named after the
initials of this first patient. Primary
infection with BKV typically occurs in childhood, probably as a mild
upper respiratory infection.
Studies suggest over 90% of the population has been infected with BK
virus by the age of ten years.
Following primary infection, the virus establishes latency in the
urogenital tract where it remains for
life. Reactivation of the virus can occur spontaneously or, more
commonly, in an
immunocompromised host.
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Bone Marrow
Transplantation
Bone marrow transplantation
(BMT) is a special therapy for patients with
cancer or other diseases which affect the bone
marrow. A bone marrow transplant involves taking
cells that are normally found in the bone marrow
(stem cells), filtering those cells, and giving
them back either to the patient they were taken
from or to another person. The goal of BMT is to
transfuse healthy bone marrow cells into a
person after their own unhealthy bone marrow has
been eliminated.
The bone marrow is a soft,
spongy tissue found inside the bones. The bone
marrow in the hips, breast bone, spine, ribs,
and skull contain cells that produce the body's
blood cells. The bone marrow is responsible for
the development and storage of about 95 percent
of the body's blood cells. The three main types
of blood cells produced in the bone marrow
include:
-
red blood
cells (erythrocytes)
-
carry oxygen
to the tissues in the body.
-
white blood
cells (leukocytes)
-
help fight
infections and to aid in the immune system.
-
platelets
-
help with
blood clotting.
Each of these cells carries
a life-maintaining function. The bone marrow is
a vital part of the human body.
Every type of blood cell in
the bone marrow begins as a stem cell. Stem
cells are immature cells that are able to
produce other blood cells that mature and
function as needed.
Stem cells are the most
important cells needed in a bone marrow
transplant. Stem cells, when transplanted, find
their way to the recipient's marrow and begin to
differentiate and produce all types of blood
cells that are needed by the body.
The goal of a bone marrow
transplant is to cure many diseases and types of
cancer. When a child's bone marrow has been
damaged or destroyed due to a disease or intense
treatments of radiation or chemotherapy for
cancer, a bone marrow transplant may be needed.
A bone marrow transplant
can be used to:
-
replace
diseased, non-functioning bone marrow with
healthy functioning bone marrow (for
conditions such as leukemia, aplastic
anemia, and sickle cell anemia).
-
replace
the bone marrow and restore its normal
function after high doses of chemotherapy or
radiation are given to treat a malignancy.
This process is often called "rescue" (for
diseases such as lymphoma and neuroblastoma).
-
replace
bone marrow with genetically healthy
functioning bone marrow to prevent further
damage from a genetic disease process (such
as Hurler's syndrome and
adrenoleukodystrophy disorder).
Bone marrow transplantation
has risks involved, some of which are life
threatening. The risks and benefits must be
weighed in a thorough discussion with the bone
marrow transplant team prior to the procedure.
Each child experiences
diseases differently and a bone marrow
transplantation may not be appropriate for
everyone who suffers from these diseases. Some
of the diseases that have been treated with bone
marrow transplant include the following:
-
leukemia
-
lymphomas
-
some
solid tumors (i.e., neuroblastoma,
rhabdomyosarcoma, brain tumors)
-
aplastic anemia
-
immune
deficiencies (severe combined
immunodeficiency disorder, Wiskott-Aldrich
syndrome)
-
sickle
cell disease
-
thalassemia
-
Blackfan-Diamond anemia
-
metabolic/storage diseases (i.e., Hurler's
syndrome, adrenoleukodystrophy disorder)
-
cancer
of the kidneys
There are different types
of bone marrow transplants depending on who the
donor is. The different types of bone marrow
transplant include the following:
-
autologous bone
marrow transplant
The donor is the child him/herself. Stem
cells are taken from the child either by
bone marrow harvest or apheresis (a process
of collecting peripheral blood stem cells)
and then given back to the child after
intensive treatment. Often the term "rescue"
is used instead of "transplant."
-
allogeneic bone
marrow transplant
The donor shares the same genetic type as
the child. Stem cells are taken either by
bone marrow harvest or apheresis from a
genetically-matched donor, usually a brother
or sister. Other donors for allogeneic bone
marrow transplants include:
-
a
parent - a haploid-identical match is
when the donor is a parent and the
genetic match is at least half identical
to the recipient.
-
an
identical twin - a syngeneic transplant
is an allogeneic transplant from an
identical twin. Identical twins are
considered a complete genetic match for
a marrow transplant.
-
unrelated bone marrow transplants (UBMT
or MUD for matched unrelated donor) -
the genetically matched marrow or stem
cells are from an unrelated donor.
Unrelated donors are found through the
national bone marrow registries.
-
umbilical cord blood
transplant
Stem cells are taken from an umbilical cord
immediately after delivery of an infant.
These stem cells reproduce into mature,
functioning blood cells quicker and more
effectively than do stem cells taken from
the bone marrow of another child or adult.
The stem cells are tested, typed, counted,
and frozen until they are ready to be
transplanted.
Because
the stem cells are "new," they are able to
produce more blood cells from each stem
cell. Another advantage cord blood has is
that the T-lymphocytes (part of the immune
system that causes graft-versus-host
disease) are not completely functional this
early in the stage of life. Recipients of
cord blood transplants have a decreased risk
for severe graft-versus-host disease.
Spinal Tap (LP)
In
medicine,
a lumbar puncture (colloquially known as
a spinal tap) is a
diagnostic
and at times
therapeutic
procedure that is performed in order to collect
a sample of
cerebrospinal fluid
(CSF) for
biochemical,
microbiological,
and
cytological
analysis, or as a treatment with injection
of chemotherapy for various cancer protocols.
Bronchoscopy
A
technique
of visualizing the inside of the
airways
for diagnostic and therapeutic
purposes. An instrument
(bronchoscope) is inserted into
the airways, usually through the
nose or mouth, or occasionally
through a
tracheostomy.
This allows the practitioner to
examine the patient's airways
for abnormalities such as
foreign bodies, bleeding,
tumors,
or
inflammation.
Specimens may be taken from
inside the lungs:
biopsies,
fluid (bronchoalveolar
lavage), or
endobronchial brushing. The
construction of bronchoscopes
ranges from rigid metal tubes
with attached lighting devices
to flexible fibreoptic
instruments with realtime video
equipment.
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