Updated: 7/11/2019

Transplant

0%
Topic
Review Topic
0
0
N/A
N/A
Questions
2 2
0
0
Snapshot
  • A 55-year-old-woman presents with nausea and yellowing of the skin to her primary care physician. Medical history is significant for a liver transplantation approximately 1.5 weeks prior to presentation. On physical examination there is scleral icterus and mild ascites. A liver biopsy shows lymphocytic infiltrates in the interstitium. (Acute rejection)
Introduction
  • Transplantation is a process by which
    • cells, tissues, or organs (graft) from the donor are transplanted into a host (or recipient)
  • The immune system's ability to recognize and respond to foreign antigens bring challenges to transplantation
    • all transplant patients or on immunosuppressive agents which increases their risk of infection 
  • There are several types of grafts
    • autograft
      • tissue is moved from one location to another in the same person
        • e.g., skin graft and using the saphenous vein to replace a coronary artery
      • the graft will not be considered foreign and will not require lifelong immunosuppresion
    • syngeneic graft (isograft)
      • tissue is transplanted from one genetically identical donor to the host
        • e.g., transplantation between monozygotic twins
    • allograft
      • tissue is transplanted from one genetically different donor of the same species to the host
        • e.g., kidney transplant
    • xenograft
      • tissue is transplanted from a donor of a different species to the host
        • e.g., porcine heart valve
Transplant Rejection
 
Transplant Rejection
Rejection Type
Pathogenesis
Comments
Hyperacute 
  • Type II hypersensitivity reaction where 
    • pre-existing recipient antibodies attack the donor antigen resulting in
      • complement activation
      • endothelial damage
      • inflammation
      • thrombosis
  • Time
    • minutes to hours
  • Findings
    • capillary thrombosis which
      • prevents graft vascularization
Acute
  • Cellular rejection
    • type IV hypersensitivity reaction where
      • recipient CD8+ T-cells react to donor antigens after activation by antigen presenting cells 
  • Humoral rejection
    • just like in hyperacute rejection; however,
      • the antibodies are formed after transplantation occured
  • Time
    • weeks to months
  • Findings
    • graft vessel vasculitis with
      • lymphocytic infiltrates
  • Treatment
    • Renal 
      • Continue calcineurin inhibitors (i.e., tacrolimus, cyclosporine) and add IV steroids
Chronic 
  • Type II and IV hypersensitivity reaction secondary to
    • CD4+ T-cells responding to the host's antigen presenting cells
  • Time
    • months to years
  • Findings
    • cytokine secretion after T-cell activation leads to
      • smooth muscle proliferation
      • interstitial fibrosis
      • parenchymal atrophy
Graft-versus-host disease
  • Type IV hypersensitivity reaction secondary to
    • the donor's T-cells attacking the recipient's cells leading to 
      • organ dysfunction
  • Time
    • variable
  • Findings
    • maculopapular rash
    • jaundice
    • diarrhea
    • hepatosplenomegaly
 
Tissue Compatibility Testing
  • ABO blood typing
  • Tissue typing
    • used to see if HLA antigens match and subtypes include
      • HLA-A
      • HLA-B
      • HLA-DR

References

 

Please rate topic.

Average 5.0 of 1 Ratings

Questions (2)
Question locked
Sorry, this question is for
PEAK Premium Subscribers only
Upgrade to PEAK

(M2.RH.14.141) A 37-year-old woman with a history of a kidney transplant presents with a cough, fever, and fatigue. Her symptoms started 1 week ago and have been steadily worsening. She has a history of IV drug use and worked in the past as a commercial sex work in her 20's. She recently traveled to Malasia 1 month ago. Her temperature is 101°F (38.3°C), blood pressure is 114/64 mmHg, pulse is 110/min, respirations are 19/min, and oxygen saturation is 93% on room air. Her physical exam is notable for bilateral coarse breath sounds. Laboratory values are ordered as seen below.

Serum:
Na+: 140 mEq/L
Cl-: 102 mEq/L
K+: 4.7 mEq/L
HCO3-: 22 mEq/L
BUN: 30 mg/dL
Glucose: 96 mg/dL
Creatinine: 1.5 mg/dL (baseline 1.4 mg/dL)
Ca2+: 9.1 mg/dL

A chest radiograph is obtained as seen in Figure A and a CT scan of the chest is obtained as seen in Figure B. Which of the following is the most likely predisposing risk factor for this patient's presentation?
Tested Concept

QID: 104147
FIGURES:
1

HIV

8%

(3/38)

2

IV drug use

18%

(7/38)

3

Medication

5%

(2/38)

4

Transplant rejection

50%

(19/38)

5

Tuberculosis

13%

(5/38)

M 8 E

Select Answer to see Preferred Response

Topic COMMENTS (13)
Private Note