Transplantation medicine Flashcards
Immunosuppresion after transplantation is a matter of balance between rejection & complications. What are the dangers of each? (2x2)
Rejection:
1. Graft failure
2. Graft dysfunction
Complication:
1. Malignancies
2. Infections
What was an important factor allowing for a strong decrease in acute organ rejection over the past decades?
Introduction of calcineurin inhibitors
Which drugs are calcineurin inhibitors? (2)
- Cyclosporine
- Tacrolimus
What is the effect of the introduction of calcineurin inhibitors on long-time graft survival?
No significant improvement -> beneficial effect of calcineurin inhibitors disappears after 1 year, after that, surival curves run parallel to old immunosuppressive regimen curves
What is the most common cause of graft loss?
Death with functioning graft
What are the causes of death with functioning graft? How many % do they each comprise? (5)
- Cardiovascular: 34%
- Infection: 16%
- Malignancy: 15%
- GI/liver complications: 6%
- Other: 29%
True or false: immunosuppression after transplantation increases the risk of some malignancies
False; (virtually) all malignancies are increased
What is the most prevalent type of tumour in transplantation patients?
Skin cancer
How much is the risk of skin cancer elevated in Tx-recipients compared to normal population?
125x
Which types of skin cancer are increased in Tx-recipients? (5)
- Melanoma
- Squamous cell carcinoma (SCC)
- Basal cell carcinoma (BCC)
- Kaposi sarcoma
- Merkel cell tumours
What are the risk factors for skin cancer in Tx-recipients? Are they different from non Tx-recipients?
- UV radiation
- Fair phenotypic features
- Geographic location
- History of SCC/BCC
- Viral infection: HHV8, HPV
- Genetic factors
Which genetic polymorphisms especially predispose for skin cancer?
Polymorphims in folate pathways
What are Tx-specific risk factors for skin cancer (and cancer more generally)? (3)
- Age at transplantation
- Type of transplant
- Type, duration & intensity of immunosuppression
What is the cumulative incidence of non-melanoma skin cancer (NMSC) in Tx-recipients after 5 and 20 years?
<5 years: 29%
>20 years: 82%
Which skin cancer type behaves significantly different in skin cancer patients?
Squamous cell carcinoma -> more aggressive & invasive
Incidences of solid tumours post-Tx are not equal in every country and even differ between transplantation centres. What differentiates them? (4)
- Genetics
- Environmental conditions
- Patient population accepted for Tx
- Immunosuppressive regimens used
How much increased are the odds of invasive solid tumours in Tx-recipients compared to the general population?
15,7x increased
Which types of cancer don’t have an increased incidence in Tx-recipients? (3) Why?
- Mamma
- Prostate
- Lung
These cancers already have a high incidence -> immunosuppression doesn’t excessively increase epidemiological risk
How many years post-Tx do solid tumours typically occur?
~15 years
Through which mechanisms do anti-T-cell therapies in Tx-patients contribute to malignancy?
Specific increase of virus-associated tumours
What is an example of a tumour that can occur due to decreased T-cell surveillance due to immunosuppression in transplant patients?
EBV-related post-transplant lymphoproliferative disease (PTLD)
How does EBV-related post-transplant lymphoproliferative disease (PTLD) develop? (3)
- EBV-infected cells are normally held in check by CD8+
- Immunosuppression reduced CD8+ surveillance, allowing expansion of EBV-infected B-cells
- PTLD
How can the risk of EBV-related post-transplant lymphoproliferative disease (PTLD) be lowered?
Addition of rituximab if anti-T-cell therapy is used
How is EBV-related post-transplant lymphoproliferative disease (PTLD) treated?
Rituximab