Recent Updates in Neuropsychiatric Complications of Organ Transplantation and their Management

Abstract

Organ transplantation is one of the most dynamic fields in medicine and has evolved into a life-saving option for thousands of patients with previously fatal conditions. The posttransplantation clinical course is frequently associated with neurologic complications that are usually related to pretransplant morbidity, the surgical procedure of transplantation, immunosuppression, and opportunistic infection (Pless and Zivkovic, 2002). Approximately one-third of transplant recipients experiences neurologic alterations with incidence ranging from 10% to 59%. The complications can be divided into such of those common to all types of transplant and others of those specific to transplanted organ. The most common complication seen with all types of transplanted organ is neurotoxicity attributable to immunosuppressive drugs, followed by seizures, opportunistic central nervous system (CNS) infections, cerebrovascular events, encephalopathy and de novo CNS neoplasms (Senzolo et al.,2009). 1- Neurotoxicity The immunosuppressants required after transplant cause peripheral neuropathy with an incidence of 10% to 60%. Peripheral neuropathy adversely affects health-related quality of life in other populations (Textor and Hedrick, 2012). 2- Seizures New-onset seizures occur in 2 % to 24 % of SOT patients (Shepard and St. Louis, 2012) Making seizures the second most common neurologic complication after SOT (Senzolo et al., 2009).

3-Infection The frequency of admissions due to infections during the first 6 months after transplantation remained unchanged over time, but increased in the 6–24 month period in patients of more recent vintage. Infections also increase the risk of new onset diabetes after transplantation (NODAT), cardiovascular events; post-transplant lymphoproliferative disorders (PTLD) and adversely affect allograft outcomes (Jha, 2010). 4-Cerbrovascular Neuroimaging features of ischemic brain infarcts or hemorrhages after transplantation do not differ when compared to non-transplant patients, but unusual causes of stroke are much more prevalent. The spectrum of cerebrovascular disorders also varies depending on transplanted organ. Ischemic strokes are relatively common in heart and kidney transplant recipients, while intracranial hemorrhages are more common after liver transplantation (Zivkovic, 2007). 5-Encephaopathy A special subcategory of encephalopathy in organ transplant recipients is posterior reversible encephalopathy syndrome (PRES) or reversible posterior leukoencephalopathy syndrome (RPLS) (Pruitt et al., 2013). Posterior reversible encephalopathy syndrome (PRES) is a neurotoxic state accompanied by a unique brain imaging pattern typically associated with a number of complex clinical conditions including: preeclampsia/eclampsia, allogeneic bone marrow transplantation, solid organ transplantation, autoimmune diseases and high dose cancer chemotherapy. The mechanism behind the developing vasogenic edema and CT or MR imaging appearance of PRES is not known (Bartynski, 2008).