Post-transplant lymphoproliferative disorder
| Post-transplant lymphoproliferative disorder | |
|---|---|
| Classification and external resources | |
| Specialty | Lua error in Module:Wikidata at line 446: attempt to index field 'wikibase' (a nil value). |
| ICD-9-CM | 238.77 |
| ICD-O | M9970/1 |
| DiseasesDB | 34154 |
| eMedicine | ped/2851 |
| Patient UK | Post-transplant lymphoproliferative disorder |
Post-transplant lymphoproliferative disorder (PTLD) is the name given to a B-cell proliferation due to therapeutic immunosuppression after organ transplantation. These patients may develop infectious mononucleosis-like lesions or polyclonal polymorphic B-cell hyperplasia. Some of these B-cells may undergo mutations which will render them malignant, giving rise to a lymphoma.[citation needed]
In some patients, the malignant cell clone can become the dominant proliferating cell type, leading to frank lymphoma, a group of B cell lymphomas occurring in immunosuppressed patients following organ transplant.
Causes
The disease is an uncontrolled proliferation of B cell lymphocytes latently infected with Epstein-Barr virus.[1][2] Production of an interleukin-10, an endogenous, pro-regulatory cytokine, has also been implicated.
In immunocompetent patients, Epstein-Barr virus can cause infectious mononucleosis in adolescent, which is otherwise asymptomatic in children during their childhood. However in immunosuppressed transplant patients, the lack of T-cell immunosurveillance can lead to the proliferation of these EBV-infected of B-lymphocytes.
However, calcineurin inhibitors (tacrolimus and cyclosporine), used as immunosuppressants in organ transplantation inhibit T cell function, and can prevent the control of the B cell proliferation.
Depletion of T cells by use of anti-T cell antibodies in the prevention or treatment of transplant rejection further increases the risk of developing post-transplant lymphoproliferative disorder. Such antibodies include ATG, ALG and OKT3.
Polyclonal PTLD may form tumor masses and present with symptoms due to a mass effect, e.g. symptoms of bowel obstruction. Monoclonal forms of PTLD tend to form a disseminated malignant lymphoma.
Treatment
PTLD may spontaneously regress on reduction or cessation of immunosuppressant medication,[3] and can also be treated with addition of anti-viral therapy. In some cases it will progress to non-Hodgkin's lymphoma and may be fatal. A phase 2 study of adoptively transferred EBV-specific T cells demonstrated high efficacy with minimal toxicity.[4]
