Transfusion-associated graft versus host disease
Encyclopedia
Transfusion-associated graft versus host disease (TA-GvHD) is a rare complication of blood transfusion
Blood transfusion
Blood transfusion is the process of receiving blood products into one's circulation intravenously. Transfusions are used in a variety of medical conditions to replace lost components of the blood...

, in which the donor T lymphocytes
T cell
T cells or T lymphocytes belong to a group of white blood cells known as lymphocytes, and play a central role in cell-mediated immunity. They can be distinguished from other lymphocytes, such as B cells and natural killer cells , by the presence of a T cell receptor on the cell surface. They are...

 mount an immune response against the recipient's lymphoid tissue. Donor lymphocytes are usually identified as foreign and destroyed by the recipient's immune system. However, in situations where the recipient is immunocompromised (inborn immunodeficiency
Immunodeficiency
Immunodeficiency is a state in which the immune system's ability to fight infectious disease is compromised or entirely absent. Immunodeficiency may also decrease cancer immunosurveillance. Most cases of immunodeficiency are acquired but some people are born with defects in their immune system,...

, acquired immunodeficiency, malignancy), or when the donor is homozygous and the recipient is heterozygous for an HLA
Human leukocyte antigen
The human leukocyte antigen system is the name of the major histocompatibility complex in humans. The super locus contains a large number of genes related to immune system function in humans. This group of genes resides on chromosome 6, and encodes cell-surface antigen-presenting proteins and...

 haplotype
Haplotype
A haplotype in genetics is a combination of alleles at adjacent locations on the chromosome that are transmitted together...

 (as can occur in directed donations from first-degree relatives), the recipient's immune system is not able to destroy the donor lymphocytes. This can result in graft versus host disease.

Epidemiology and pathogenesis

The incidence in immunocompromised patients receiving blood transfusions is estimated to be 0.1 - 1.0%, mortality around 80 - 90%. Mortality is higher in TA-GvHD than in GvHD associated with bone marrow transplantation, where the engrafted lymphoid cells in the bone marrow
Bone marrow
Bone marrow is the flexible tissue found in the interior of bones. In humans, bone marrow in large bones produces new blood cells. On average, bone marrow constitutes 4% of the total body mass of humans; in adults weighing 65 kg , bone marrow accounts for approximately 2.6 kg...

 are of donor origin; therefore, the immune reaction is not directed against them.

The most common cause of death
Cause of Death
Cause of Death is a 1990 album by American death metal band Obituary. Cause of Death is considered a classic album in the history of death metal. The artwork was done by artist Michael Whelan...

 in TA-GvHD is infections and hemorrages, secondary to pancytopenia and liver dysfunction.

Clinical manifestations

The clinical presentation is the same as GvHD occurring in other settings, such as bone marrow transplantation. TA-GvHD can develop four to thirty days after the transfusion. Typical symptoms include:
  • fever
    Fever
    Fever is a common medical sign characterized by an elevation of temperature above the normal range of due to an increase in the body temperature regulatory set-point. This increase in set-point triggers increased muscle tone and shivering.As a person's temperature increases, there is, in...

  • erythematous maculopapular rash
    Maculopapular rash
    A maculopapular rash is a type of rash characterized by a flat, red area on the skin that is covered with small confluent bumps. The term "maculopapular" is a compound: macules are small, flat discolored spots on the surface of the skin; and papules are small, raised bumps...

    , which can progress to generalised erythroderma
    Erythroderma
    Erythroderma is an inflammatory skin disease with erythema and scaling that affects nearly the entire cutaneous surface....

  • toxic epidermal necrolysis
    Toxic epidermal necrolysis
    Toxic epidermal necrolysis is a rare, life-threatening dermatological condition that is usually induced by a reaction to medications...

     in extreme cases


Other symptoms can include cough, abdominal pain, vomiting, and profuse diarrhea
Diarrhea
Diarrhea , also spelled diarrhoea, is the condition of having three or more loose or liquid bowel movements per day. It is a common cause of death in developing countries and the second most common cause of infant deaths worldwide. The loss of fluids through diarrhea can cause dehydration and...

 (up to 8 liter
Litér
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s/day).

Laboratory manifestations

Laboratory findings include pancytopenia
Pancytopenia
Pancytopenia is a medical condition in which there is a reduction in the number of red and white blood cells, as well as platelets.If only two parameters from the full blood count are low, the term bicytopenia can be used...

, abnormal liver enzymes
Liver function tests
Liver function tests , are groups of clinical biochemistry laboratory blood assays designed to give information about the state of a patient's liver. The parameters measured include PT/INR, aPTT, albumin, billirubin and others...

, and electrolyte imbalance (when diarrhea is present).

Diagnosis

TA-GvHD can be suspected from a biopsy
Biopsy
A biopsy is a medical test involving sampling of cells or tissues for examination. It is the medical removal of tissue from a living subject to determine the presence or extent of a disease. The tissue is generally examined under a microscope by a pathologist, and can also be analyzed chemically...

 of the affected skin, and established by HLA
Human leukocyte antigen
The human leukocyte antigen system is the name of the major histocompatibility complex in humans. The super locus contains a large number of genes related to immune system function in humans. This group of genes resides on chromosome 6, and encodes cell-surface antigen-presenting proteins and...

 analysis of the circulating lymphocytes. This testing can identify circulating lymphocytes with a different HLA type than the tissue cells of the host.

Treatment and prevention

Treatment is only supportive, as no available form of therapy has proven effective in treating TA-GvHD.

Prevention includes gamma
Gamma ray
Gamma radiation, also known as gamma rays or hyphenated as gamma-rays and denoted as γ, is electromagnetic radiation of high frequency . Gamma rays are usually naturally produced on Earth by decay of high energy states in atomic nuclei...

 irradiation
Irradiation
Irradiation is the process by which an object is exposed to radiation. The exposure can originate from various sources, including natural sources. Most frequently the term refers to ionizing radiation, and to a level of radiation that will serve a specific purpose, rather than radiation exposure to...

 of the lymphocyte-containing blood products. This procedure should be performed in transfusions when:
  • the recipient is immunocompromised
  • the blood components are from a family donor
  • HLA-matched platelets are transferred.

Another means of prevention is the use of third- or fourth-generation leukoreduction
Leukoreduction
Leukoreduction is the removal of white blood cells from the blood or blood components supplied for blood transfusion. After the removal of the leukocytes, the blood product is said to be leukoreduced.- Benefits and costs :...

filters, although the efficacy of this procedure has not yet been documented.
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