Analysis of clinical variables associated with tolerance in pediatric liver transplant recipients.

Tolerance has been defined as stable graft function off IMS. We reviewed the data of 369 pediatric liver transplant patients to examine demographic differences that may have a PV of pediatric LT tolerance. Of the 369 patients, 280 patients were stable with detectable blood levels of IMS agents and with good graft function without biopsy proven REJ > 1 yr posttransplantation, 18 patients were noted to be TOL off IMS, 27 patients were taking MIS with drug levels below detectable range by standard laboratory parameters, and 44 patients developed one or more episodes of biopsy proven acute or chronic REJ > 1 yr post-transplantation. Variables, including percentage of biliary atresia, type of transplanted organ, history of EBV infection, patient and donor gender, and ABO blood type mismatch between recipient and donor did not have PV of tolerance. Average age in years was 1.37 ± 1.53 (0.3-4.9) for TOL, 1.14 ± 0.89 (0.4-3.1) for MIS and 3.35 ± 4.45 (0.3-16) for REJ. Age difference of TOL/MIS vs. REJ was significant (p =0.002) and TOL vs. REJ was significant (0.01). Age at the time of transplantation is an important predictor in the development of pediatric LT tolerance.

Expression of soluble HLA-G identifies favorable outcomes in liver transplant recipients.

BACKGROUND: Human leukocyte antigen (HLA)-G displays immunotolerogenic properties toward the main effector cells involved in graft rejection through inhibition of natural killer cell- and cytotoxic T-lymphocyte-mediated cytolysis, and CD4 T-cell alloproliferation. An increase in serum and graft levels of HLA-G has been noted in transplant patients with improved allograft survival. However, the clinical relevance of soluble serum HLA-G molecules in tolerant pediatric and young adult liver transplant patients remains to be studied. METHODS: We examined the serum HLA-G levels in 42 pediatric and young adult liver transplant patients with a mean age of 15 years; 13 patients had operational tolerance (TOL), with complete immunosuppression withdrawal for 2.3 to 13.2 years. RESULTS: Median HLA-G level in patients with acute rejection (AR) was similar to the level in pediatric healthy volunteers (9.9 vs. 4.2 U/mL, P=0.13). HLA-G was higher in patients with stable liver function on immunosuppression (54.6 U/mL) than in patients with AR (P=0.01) and healthy volunteers (P=0.003), but almost 6-fold lower than in TOL patients (325.4 U/mL). HLA-G did not correlate with clinical confounders or a history of posttransplant lymphoproliferative disease or Epstein-Barr virus; although levels in the TOL group were negatively correlated with time after immunosuppression withdrawal (r=-0.75, P=0.003). In rejectors, HLA-G levels trended to negatively correlate with a higher number (r=-0.58) and greater severity of AR episodes (r=-0.56) after 1 year posttransplantation. CONCLUSIONS: Increased serum HLA-G levels track with operational tolerance of liver grafts and support favorable outcomes in pediatric and young adult recipients.

Electron beam CT scan is a valuable and safe imaging tool for the pediatric surgical patient.

PURPOSE: Electron beam computed tomography (EBCT) is a relatively new technology that has been used primarily to detect coronary artery calcification in adult patients. EBCT has several potential advantages over traditional CT: (1) fast acquisition times resulting in less need for sedation, (2) decreased radiation exposure, and (3) robust software enabling real-time interactive 3-dimensional visualization of anatomic relationships. In this series of case reports, the authors describe their initial experience with the use of EBCT in pediatric noncardiac imaging. METHODS: Children with a variety of thoracic and abdominal disease processes were evaluated by EBCT. RESULTS: All patients underwent EBCT scanning without the need for sedation, and 3-dimensional images of the data sets were rendered in minutes after their acquisition. The diagnostic images provided equivalent spatial resolution to the multislice CT scanner but without motion artifacts and lower radiation exposure. CONCLUSIONS: EBCT is a safe, effective, and user- and patient-friendly alternative to traditional CT in the care of pediatric surgical diseases. The diagnostic yield of EBCT will continue to improve with new technologic advances and clinical experience.

Temtamy-like syndrome associated with translocation of 2p24 and 9q32.

We describe the phenotype of a 5 year old girl with features resembling Temtamy syndrome, including agenesis of the corpus callosum, ventriculomegaly, frontal bossing, peaked eyebrows, ptosis, malformed and low set ears, a depressed nasal bridge, a long philtrum, and iris and chorioretinal colobomas. Features unique to this child include profound mental retardation, bilateral sensorineural hearing loss, agenesis of the corpus callosum, patent ductus arteriosus, ventricular septal defect, unilateral renal agenesis, neurogenic bladder and hydronephrosis. High resolution chromosome analysis demonstrated a de novo, balanced translocation [46,XX,t(2;9)(p24;q32)]; and her case has some overlapping phenotypic features with cases of monosomy for 2p. This is the first documented case of Temtamy syndrome with a specific chromosomal anomaly, and will assist with the elucidation of the syndrome's underlying genetic defect.