Objective: The most prevalent malignancy that complicates both adult and pediatric solid organ transplantation is post-transplant lymphoproliferative disorder (PTLD). This study aimed to analyze the clinical and pathological characteristics, treatments, and outcomes of EBV viremia and PTLD in pediatric liver transplant recipients. Method: A retrospective chart review was performed on 112 patients less than 18 years of age who underwent isolated orthotopic liver transplantation (OLT) between 2010 and 2022 at Ege University Children’s Hospital. Data gathered for 1-year post-OLT included age at OLT, EBV, immunoglobulin (Ig)M/IgG status of the donor and recipient, indication for OLT, induction regimen, all immunosuppression levels, date and result of EBV polymerase chain reaction (PCR) testing, rejection episodes documented by liver biopsy, and the development of PTLD. Result: Forty-nine patients (43.75%) developed EBV viremia (median interval from surgery: two months, min-max 2-36), of which 43 (87.8%) grafts came from living donors, and 6 (12.2%) came from deceased donors. Nine (18.4%) patients died during follow-up, and eight (16.3%) developed PTLD. Five patients developed EBV-related disease; one child developed hemophagocytic lymphohistiocytosis; one developed aplastic anemia; and one child developed B cell lymphoma. When PTLD patients and without-PTLD patients were compared, pediatric intensive care unit hospitalization, abnormal bone marrow biopsy findings, lymphadenopathy, age at diagnosis of EBV viremia, EBV viral load, tacrolimus (FK 506) pre-infection, and 1-month levels were higher in patients with PTLD (p<0.05). In logistic regression analysis, we showed that the age at diagnosis of EBV viremia was significantly higher in children with PTLD (p=0.045; OR, 1.389; 95% CI, 1.007-1.914). Discussion PTLD is a rare but severe complication associated with EBV after OLT. This study demonstrated that PTLD is associated with older age, higher tacrolimus blood levels before EBV viremia, at one month of EBV viremia, and higher peak EBV viral load.

Background: Studies on age-related differences in clinical and laboratory features on coronavirus disease 2019 (COVID-19) are limited. We aimed to evaluate the demographic, clinical, and laboratory findings of COVID-19 in children younger than six months old and compare them with older children. Methods: A single-center retrospective study, including 209 confirmed COVID-19 cases, was conducted between March 11, 2020, and September 1, 2021. The case group consisted of 47 patients younger than six months old, and the control group consisted of 162 patients older than six months old. Results: The mean age of the case group was 2.77±1.52 months, and the control group was 101.89±65.77 months. Cough was statistically higher in the control group, poor feeding was higher in the case group (P=.043, .010). The underlying disease ratio was statistically higher in the case group; however, the hospitalization rate was higher in the case group (P=.001, .036). The case group had significantly lower median values of the absolute neutrophil count, hemoglobin, and higher median values of white blood cell, absolute lymphocyte count, platelet than the control group (P<.05). C-reactive protein, fibrinogen values were significantly lower, and procalcitonin, D-dimer, troponin T, N‑terminal pro-B-type natriuretic peptide significantly higher in the case group (P<.05). Lymphopenia was more common in the control group, whereas neutropenia was more common in the case group (P= .001, .011). Conclusions: We showed that most children younger than six months old had mild and asymptomatic COVID-19; however, the hospitalization rate was higher, and neutropenia was more common than older children.