Post‐Transplant Metabolic Syndrome in Pediatric Liver Transplant Recipients: Definition, Prevalence and Clinical Presentation

Over the last decades, long-term survival after pediatric liver transplantation (LT) has improved substantially, highlighting the importance of long-term graft and recipient outcomes. Metabolic syndrome, a combination of components associated with increased cardiovascular risk, is a well-defined concept in the general adult population. The same components can be present after LT leading to post-transplant metabolic syndrome (PTMS). In children, PTMS is estimated to be prevalent in around 14%-20% of LT recipients. However, a univocal definition is lacking as well as consensus on specific cut-off values for the different components. The latter comprise: low HDL-cholesterol, high triglycerides (both falling under the heading of "dyslipidemia"), hypertension, impaired fasting glucose and/or impaired glucose tolerance, and (abdominal) obesity. Although most studies have a retrospective or cross-sectional nature and are of relatively small sample size, there seems to be an accumulation of risk factors in the first years after transplantation, declining thereafter and rising again in the long term. Sustained exposure to immunosuppression is identified as a major contributor, as well as accumulating general cardiometabolic risk factors throughout life.