Graft-versus-host
disease is a complication of allogeneic
bone marrow transplantation and some other types
of solid organ transplantation. After transplantation,
T cells present in the graft tissue attack the tissues
of the transplant recipient. The T-cells attack
because they view the new recipient tissues as foreign
antigen. Essentially, graft-versus-host-disease
is a pathological condition in which cells from
donor tissues and organs initiate an immunologic
attack on the cells and tissue of the recipient.
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Graft-versus-host-disease
(GVHD) is divided into acute and chronic forms.
The acute or fulminant form of the disease
is observed within the first 100 days post-transplant,
and the chronic form of GVHD is defined as
that which occurs after 100 days. Acute and
chronic graft-versus-host-disease appear to
involve different immune cell subsets and
different types of target organ damage. |
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Classically, acute GVHD
is characterized by selective damage to the
liver, skin, mucosa, and the gastrointestinal
tract. Chronic GVHD damages the above organs,
but also causes changes to the connective
tissue (e.g. of the skin and exocrine glands). |
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GVHD of the GI tract
can result in diarrhea, abdominal pain, nausea,
vomiting. It is diagnosed with a biopsy of
the intestinal lining. |
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Liver GVHD is diagnosed
by measuring bilirubin levels. |
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Skin GVHD results in
a generalized rash that is red and raised
in acute GVHD. In chronic GVHD, the skin can
become firm (sclerotic) and hyperpigmented.
The skin may become so inelastic in chronic
GVHD that contractures develop around joints
that significantly limit movement. This form
of chronic GVHD is termed “sclerodermoid”
because it resemble the connective tissue
disease, scleroderma. |
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Skin biopsies of GVHD
may or may not be helpful in making the diagnosis,
but they are generally performed to assist
physicians when there is clinical suspicion
of GVHD. |
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The treatment of acute
GVHD is generally combination immunosuppressant
regimens, plasmapheresis or both. |
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The treatment of chronic
GVHD is the same as above, but it may also
be very helpful to combine these regimens
with phototherapy (UVA-1 or narrowband UVB). |
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