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Zorluk: ZorHematology and Oncology

An oncology consultation is requested for a 34-year-old man admitted to the intensive care unit due to profound pancytopenia and severe watery diarrhea. The patient has a history of classical Hodgkin lymphoma, for which he completed systemic chemotherapy three months ago. Two weeks prior to this admission, he presented to an outpatient clinic with symptomatic anemia and received two units of packed red blood cells donated by his healthy biological brother. Over the last four days, he has developed a diffuse, erythematous maculopapular rash involving the palms and soles, abdominal cramping, and jaundice. Vital signs reveal a temperature of 39.4∘C39.4^\circ\text{C} (102.9∘F102.9^\circ\text{F}), blood pressure of 105/65 mmHg, and heart rate of 115/min. Laboratory studies show:

ParameterResult
Hemoglobin6.2 g/dL
White blood cell count800/μL800/\mu\text{L} (Neutrophils: 10%)
Platelet count15,000/μL15,000/\mu\text{L}
Total bilirubin4.5 mg/dL
Alkaline phosphatase420 U/L
Alanine aminotransferase (ALT)180 U/L
Aspartate aminotransferase (AST)150 U/L

Which of the following pre-transfusion blood product modifications would have most likely prevented this patient's current condition?

  1. Gamma irradiationCevap
  2. B
    Leukoreduction
  3. C
    Washing with saline
  4. D
    Solvent-detergent treatment
  5. E
    Warming to 37∘C37^\circ\text{C}

Cevap

Gamma irradiation
Gamma irradiation of cellular blood products (packed red blood cells and platelets) cross-links the DNA of donor T-lymphocytes, thereby rendering them incapable of proliferating. This is the only effective method to prevent transfusion-associated graft-versus-host disease (TA-GVHD). TA-GVHD is a rare, highly fatal complication that occurs when viable donor T-cells attack the recipient's tissues (classic tetrad: skin rash, diarrhea, liver dysfunction, and bone marrow aplasia/pancytopenia). Gamma irradiation is strictly indicated for susceptible populations, which notably includes patients with cellular immunodeficiencies (e.g., Hodgkin lymphoma, prior stem cell transplants, use of purine analogs) and any patient receiving a directed blood donation from a first-degree relative. In family-directed donations, shared HLA haplotypes prevent the recipient's immune system from recognizing the donor cells as foreign, allowing the donor T-cells to engraft and attack the unshared recipient HLA antigens.

Adım Adım Çözüm

1
Analyze the patient's clinical presentation and timeline.
The patient developed a severe maculopapular rash, secretory diarrhea, hepatitis (elevated LFTs and bilirubin), and profound pancytopenia two weeks after receiving a blood transfusion.
Establishing the sequence of events and the affected organ systems (skin, GI tract, liver, bone marrow) points toward a systemic immunologic process.
2
Identify the underlying diagnosis based on the clinical triad and history.
The diagnosis is Transfusion-Associated Graft-Versus-Host Disease (TA-GVHD).
TA-GVHD classically presents 1 to 4 weeks post-transfusion with rash, hepatomegaly/jaundice, diarrhea, and severe bone marrow aplasia (pancytopenia).
3
Determine the patient's specific risk factors for TA-GVHD.
The patient has a history of Hodgkin lymphoma (causing a cellular immunodeficiency) and received a directed blood donation from a first-degree relative.
TA-GVHD occurs when donor T-lymphocytes recognize the recipient as foreign and mount an attack, while the recipient cannot reject the donor cells. This happens in immunocompromised hosts or when an immunocompetent recipient receives blood from an HLA-haploidentical relative (the recipient does not recognize the donor as foreign).
4
Select the appropriate preventive measure.
Gamma irradiation of the cellular blood product.
Irradiation cross-links the DNA of donor T-lymphocytes, preventing their proliferation. It is strictly indicated for patients with Hodgkin lymphoma and for all directed donations from blood relatives.

Anahtar Kavram

Prevention of Transfusion-Associated Graft-Versus-Host Disease (TA-GVHD)
Tahmini Süre:2m 0s
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Konular

Hematology and Oncology

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