Case of the Month
Section Editor: Nicholas Stence, MD
Children's Hospital Colorado, Aurora, CO
February 2014
Next Case of the Month coming March 4 . . .
Primary Central Nervous System Posttransplantation Lymphoproliferative Disorder
- Posttransplantation lymphoproliferative disorder (PTLD) is a complication of organ transplant that rarely affects the central nervous system in isolation.
- Majority of the lesions are B-cell in origin (most common PTLD histological subtype is diffuse large B-cell lymphoma), and Epstein-Barr virus is considered to be causative in nearly 90% of cases.
- Risk factors include age, type of allograft, and type and intensity of immunosuppression (higher risk with cyclosporine and tacrolimus).
- Usually, primary central nervous system posttransplantation lymphoproliferative disorder (PCNS-PTLD) occurs during the first 4 years posttransplantation, although there are reports in the literature of the disease occurring 10 years after transplantation.
- Clinically, the most common presentation includes headache, hemiparesis, seizures, and ataxia
- Brain MRI evaluates presence of this disorder, helps target potential biopsy sites, and allows posttherapeutical monitorization.
- CSF studies are inconclusive most of the time, and the definite diagnosis is histological.
- Key Diagnostic Features: Multifocal brain involvement, predominantly in periventricular and basal ganglia regions, followed by meningeal and ependymal lesions. Less common infratentorial. Typically, lesions enhance, either homogenously or with a ring-enhancement pattern. Perilesional edema is common. Hemorrhage may occur. Variable signal intensities in T1 and T2-weighted images, with low signal in T2*-weighted images if hemorrhage is present. Restricted diffusion is not always present but may exist in solid portions. CT hyperattenuated areas may correspond to high cellularity or hemorrhage.
- DDx: Infection (abscess and toxoplasmosis), other neoplasms, toxicity from immunosuppressive agents
- Rx: Optimal treatment is challenging, implying a multidisciplinary approach. Reduction of immunosuppression is usually the therapeutic method of choice, although with increased risk of graft rejection. Chemo or radiotherapy are also viable options. Corticosteroids and antiviral agents may also be considered.