Bio

Clinical Focus


  • Gastroenterology/Nutrition/Hepatology, Pediatric
  • Pediatric Gastroenterology

Academic Appointments


Administrative Appointments


  • Associate Chair, Stanford University School of Medicine - Pediatrics (2004 - Present)
  • Sr.Assoc.Dean for Peds. & Ob.Clinical Affairs, Stanford University School of Medicine (2003 - Present)

Honors & Awards


  • Euphrat Distinguished Packard Fellow, Lucile Packard Children’s Hospital at Stanford University (2005 -)
  • Outstanding Teacher Award, Department of Pediatrics, University of California, Davis (1981-82)
  • Outstanding Teacher Award, Department of Pediatrics, University of California, Davis (1978-79)
  • Cystic Fibrosis Fellowship, Department of Pediatrics, University of California, Los Angeles (1976-78)

Professional Education


  • Medical Education:University of Washington Medical Center (1971) WA
  • Residency:University of Oregon (1974) OR
  • Internship:University of Oregon (1972) OR
  • Board Certification: Pediatrics, American Board of Pediatrics (1977)
  • Board Certification: Pediatric Gastroenterology, American Board of Pediatrics (1990)
  • Fellowship:UCLA Medical Center (1978) CA

Research & Scholarship

Current Research and Scholarly Interests


Gastroenterology, biliary motility, hormonal regulation, embryology, gastrointestinal tract, clinical management of pediatric liver transplant recipients.

Teaching

2013-14 Courses


Publications

Journal Articles


  • Markers of Antigen Presentation and Activation on Eosinophils and T Cells in the Esophageal Tissue of Patients With Eosinophilic Esophagitis JOURNAL OF PEDIATRIC GASTROENTEROLOGY AND NUTRITION Le-Carlson, M., Seki, S., Abarbanel, D., Quiros, A., Cox, K., Nadeau, K. C. 2013; 56 (3): 257-262

    Abstract

    Evidence suggests eosinophils may be acting as antigen-presenting cells (APCs) by presenting antigen to T cells. We investigated the surface proteins of eosinophils and T cells in the esophageal biopsies of patients with eosinophilic esophagitis (EoE), patients with gastroesophageal reflux disease (GERD), and healthy controls (HCs).: Subjects were categorized as EoE, GERD, or HC. In esophageal tissue, EG2+ eosinophils were stained for the APC markers, CD40 or CD80, via immunohistochemistry. CD3+ T cells were stained for costimulatory markers, CD40L or CD28, and for activation markers, CD69 or CD134, via immunofluorescence or immunohistochemistry.Eosinophils stained with CD40 and CD80. The number of EG2+CD40+ cells was increased in EoE (mean 19.1±14.8 cells/high-power field [HPF], n=11), compared with GERD (mean 0.13±0.19 cells/HPF, n=5, P<0.01) and HC (mean 0.3±0.7 cells/HPF, n=5, P<0.01). There was an elevation in EG2+CD80+ cells in EoE (mean 18.1±16.2 cells/HPF, n=10), GERD (mean 1.7±2.8 cells/HPF, n=6, P<0.01), or HC (mean 0.8±1.3 cells/HPF, n=6, P<0.01). CD3+ T cells stained with CD40L (not quantified). CD3+ T cells stained with CD28 at elevated levels in EoE (mean 14±8.7 cells/HPF, n=9) versus GERD (mean 3.3±1.2 cells/HPF, n=6, P<0.05) or HC (mean 3.0±3.2 cells/HPF, n=7, P<0.01). The number of CD3+CD69+ cells was highest in EoE (mean 14.8±7.5 cells/HPF, n=6) versus GERD (mean 0.8±0.9 cells/HPF, n=6, P<0.001) or HC (mean 2.7±2.5 cells/HPF, n=6, P<0.001).We show that esophageal eosinophils express CD40 and CD80, and T cells with CD40L, CD28, and CD69. The number of double-stained cells was higher in EoE in comparison to control groups. These data support the hypothesis that eosinophils in EoE may act as APCs, activating T cells.

    View details for DOI 10.1097/MPG.0b013e3182758d49

    View details for Web of Science ID 000315461400010

    View details for PubMedID 23059644

  • Immunomodulatory effect of vancomycin on Treg in pediatric inflammatory bowel disease and primary sclerosing cholangitis. Journal of clinical immunology Abarbanel, D. N., Seki, S. M., Davies, Y., Marlen, N., Benavides, J. A., Cox, K., Nadeau, K. C., Cox, K. L. 2013; 33 (2): 397-406

    Abstract

    Vancomycin has been shown to affect tumor necrosis factor-alpha (TNF-?) pathways as an immunomodulator; this is thought to be separate from its function as an antibiotic [1]. Previous studies have shown that oral vancomycin (OV) is an effective treatment for concomitant primary sclerosing cholangitis (PSC) and inflammatory bowel disease (IBD) in children [2, 3]. Since both diseases are associated with immune dysfunction, we hypothesized that vancomycin's therapeutic effect in IBD and PSC occurs through immunomodulation. Therefore, we examined the in vivo immunological changes that occur during OV treatment of 14 children with PSC and IBD. Within 3 months of OV administration, peripheral gamma-glutamyl transpeptidase (GGT) and alanine aminotransferase (ALT) concentrations, white blood cell (WBC) counts, and neutrophil counts normalized from elevated levels before treatment. Patients also demonstrated improved biliary imaging studies, liver biopsies and IBD symptoms and biopsies. Additionally, plasma transforming growth factor beta (TGF-?) levels were increased without concurrent shifts in Th1-or Th2-associated cytokine production. Peripheral levels of CD4?+?CD25hiCD127lo and CD4?+?FoxP3+ regulatory T (Treg) cells also increased in OV-treated PSC?+?IBD patients compared to pretreatment levels. A unique case study shows that the therapeutic effects of OV in the treatment of PSC?+?IBD do not always endure after OV discontinuation, with relapse of PSC associated with a decrease in blood Treg levels; subsequent OV retreatment was then associated with a rise in blood Treg levels and normalization of liver function tests (LFTs). Taken together, these studies support immune-related pathophysiology of PSC with IBD, which is responsive to OV.

    View details for DOI 10.1007/s10875-012-9801-1

    View details for PubMedID 23054338

  • Geographical Rural Status and Health Outcomes in Pediatric Liver Transplantation: An Analysis of 6 Years of National United Network of Organ Sharing Data JOURNAL OF PEDIATRICS Park, K. T., Bensen, R., Lu, B., Nanda, P., Esquivel, C., Cox, K. 2013; 162 (2): 313-?

    Abstract

    To determine whether children in rural areas have worse health than children in urban areas after liver transplantation (LT).We used urban influence codes published by the US Department of Agriculture to categorize 3307 pediatric patients undergoing LT in the United Network of Organ Sharing database between 2004 and 2009 as urban or rural. Allograft rejection, patient death, and graft failure were used as primary outcome measures of post-LT health. Pediatric end-stage liver disease/model of end-stage liver disease scores >20 was used to measure worse pre-LT health.In a multivariate analysis, we found greater rates of allograft rejection within 6 months of LT (OR 1.27; 95% CI 1.05-1.53) and a lower occurrence of posttransplantation lymphoproliferative disorder (OR 0.64; 95% CI 0.41-0.99) in patients in rural areas. The difference in allograft rejection was eliminated at 1 year of LT (OR 1.18; 95% CI 0.98-1.42). Rural location did not impact other outcome measures.We conclude that rural location makes a negative impact on patient health within the first 6 months of LT by increasing the risk for allograft rejection, although patients in rural areas may have lower rates of developing posttransplantation lymphoproliferative disorder. Long-term adverse health effects were not seen.

    View details for DOI 10.1016/j.jpeds.2012.07.015

    View details for Web of Science ID 000313579900021

    View details for PubMedID 22914224

  • Characteristics and Direct Costs of Academic Pediatric Subspecialty Outpatient No-Show Events J Healthc Qual Perez, F., Xie, J., Sin, A., Tsai, R., Sanders, L., Cox, K., Haberland, C., Park, K. 2013; Mar 29
  • Successful treatment of recurrent primary sclerosing cholangitis after orthotopic liver transplantation with oral vancomycin. Case reports in transplantation Davies, Y. K., Tsay, C. J., Caccamo, D. V., Cox, K. M., Castillo, R. O., Cox, K. L. 2013; 2013: 314292-?

    Abstract

    Primary sclerosing cholangitis (PSC) is a progressive, cholestatic disease of the liver that is marked by inflammation of the bile ducts and damage to the hepatic biliary tree. Approximately 60-70% of patients also have inflammatory bowel disease and progression of PSC can lead to ulcerative colitis and cirrhosis of the liver. Due to limited understanding of the etiology and mechanism of PSC, the only existing treatment option is orthotopic liver transplantation (OLT); however, recurrence of PSC, after OLT is estimated to be between 5% and 35%. We discuss the successful treatment of a pediatric patient, with recurrent PSC, after OLT with oral Vancomycin.

    View details for DOI 10.1155/2013/314292

    View details for PubMedID 23509657

  • A Common Peripheral Blood Gene Set for Diagnosis of Operational Tolerance in Pediatric and Adult Liver Transplantation AMERICAN JOURNAL OF TRANSPLANTATION Li, L., Wozniak, L. J., RODDER, S., Heish, S., Talisetti, A., Wang, Q., Esquivel, C., Cox, K., Chen, R., McDiarmid, S. V., Sarwal, M. M. 2012; 12 (5): 1218-1228

    Abstract

    To identify biomarkers of operational tolerance in pediatric and adult liver transplant recipients, transcriptional profiles were examined from 300 samples by microarrays and Q-PCR measurements of blood specimens from pediatric and adult liver transplant recipients and normal tissues. Tolerance-specific genes were validated in independent samples across two different transplant programs and validated by Q-PCR. A minimal set of 13 unique genes, highly expressed in natural killer cells (p = 0.03), were significantly expressed in both pediatric and adult liver tolerance, irrespective of different clinical and demographic confounders. The performance of this gene set by microarray in independent samples was 100% sensitivity and 83% specificity and the AUC was 0.988 for only three genes by Q-PCR. 26% of adults and 64% of children with excellent liver allograft function, on minimal or dual immunosuppression, showed high prediction scores for tolerance. Novel peripheral transcriptional profiles can be identified in operational tolerance in pediatric and adult recipients of liver allografts, suggesting a high incidence of a pro-tolerogenic phenotype in stable patients on chronic immunosuppression. Given the high incidence of viral infections and malignancies in liver transplant recipients, this gene set provides an important monitoring tool that can move the field toward personalized and predictive medicine in organ transplantation.

    View details for DOI 10.1111/j.1600-6143.2011.03928.x

    View details for Web of Science ID 000303235100020

    View details for PubMedID 22300520

  • Immunophenotyping of Peripheral Eosinophils Demonstrates Activation in Eosinophilic Esophagitis JOURNAL OF PEDIATRIC GASTROENTEROLOGY AND NUTRITION Tammie Nguyen, T., Gernez, Y., Fuentebella, J., Patel, A., Tirouvanziam, R., Reshamwala, N., Bass, D., Berquist, W. E., Cox, K. L., Kerner, J. A., Nadeau, K. C. 2011; 53 (1): 40-47

    Abstract

    Eosinophilic esophagitis (EoE) is a chronic inflammatory disorder characterized by upper gastrointestinal symptoms and the presence of high numbers of eosinophils in the esophagus. Although eosinophils in the esophagus have been found to be activated in subjects with EoE, detailed studies of intracellular signaling pathways involved in the mechanism of activation of eosinophils in EoE have heretofore been limited. The aim of the study was to assess whether any surface molecules or transcription factors are activated in peripheral eosinophils in subjects with EoE.Eosinophils and CD3+ lymphocytes were identified directly from 50 ?L of whole blood of EoE and control subjects. Using Hi-FACS, levels of surface activation markers, including CD66b, and intracellular phosphoepitopes, including phosphorylated forms of signal transducer and activator of transcription (phospho-STAT) 1 and 6, were measured within each cell subset.Levels of surface CD66b as well as levels of intracellular phospho-STAT1 and phospho-STAT6 in peripheral blood eosinophils were significantly higher for untreated subjects with EoE vs healthy controls (P < 0.05). Levels of phospho-STAT1 and phospho-STAT6 in peripheral blood eosinophils were lower in subjects with EoE on therapy versus untreated subjects with EoE (P < 0.05).Levels of phospho-STAT1 and phospho-STAT6, transcription factors involved in inflammatory processes, were both significantly higher in peripheral eosinophils from untreated (ie, newly diagnosed) subjects with EoE versus subjects with EoE on therapy, healthy controls. Blood-based measurements of CD66b and phospho-STAT levels in peripheral eosinophils may be beneficial for identifying EoE.

    View details for DOI 10.1097/MPG.0b013e318212647a

    View details for Web of Science ID 000291925500006

    View details for PubMedID 21694534

  • Effects of rural status on health outcomes in pediatric liver transplantation: A single center analysis of 388 patients PEDIATRIC TRANSPLANTATION Park, K. T., Nanda, P., Bensen, R., Strichartz, D., Esquivel, C., Cox, K. 2011; 15 (3): 300-305

    Abstract

    Rural status of patients may impact health before and after pediatric LT. We used UI codes published by the USDA to stratify patients as urban or rural depending county residence. A total of 388 patients who had LT and who met criteria were included. Rejection, PTLD, and survival were used as primary outcome measures of post-LT health. UNOS Status 1 and PELD/MELD scores >20 were used as secondary outcome measures of poorer pre-LT health. Logistic regression models were run to determine associations. We did not find any statistically significant differences in pre- or post-LT outcomes with respect to rurality. Among rural patients, there was a general trend for decreased incidence of rejection (25.0% vs. 33.4%; OR 0.64, 95% CI 0.29-1.44), increased risk of PTLD (5.6% vs. 3.4%; OR 1.86, 95% CI 0.36-3.31), and decreased survival (OR 0.85, 95% CI 0.34-2.13) after LT. Rural patients also tended to be sicker at the time of LT than patients from urban areas, with increased proportion of Status 1 (OR 1.17, 95% CI 0.51-2.70) and PELD/MELD scores >20 (OR 1.20, 95% CI 0.59-2.45). From a single center experience, we conclude that rurality did not significantly affect health outcomes after LT, although a larger study may validate the general trends that rural patients may have decreased rejection, increased PTLD, and mortality, and be in poorer health at the time of LT.

    View details for DOI 10.1111/j.1399-3046.2010.01452.x

    View details for Web of Science ID 000289628100018

    View details for PubMedID 21450010

  • Analysis of clinical variables associated with tolerance in pediatric liver transplant recipients PEDIATRIC TRANSPLANTATION Talisetti, A., Hurwitz, M., Sarwal, M., Berquist, W., Castillo, R., Bass, D., Concepcion, W., Esquivel, C. O., Cox, K. 2010; 14 (8): 976-979

    Abstract

    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.

    View details for DOI 10.1111/j.1399-3046.2010.01360.x

    View details for Web of Science ID 000285229500007

    View details for PubMedID 21108705

  • Expression of Soluble HLA-G Identifies Favorable Outcomes in Liver Transplant Recipients TRANSPLANTATION Zarkhin, V., Talisetti, A., Li, L., Wozniak, L. J., McDiarmid, S. V., Cox, K., Esquivel, C., Sarwal, M. M. 2010; 90 (9): 1000-1005

    Abstract

    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.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.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.Increased serum HLA-G levels track with operational tolerance of liver grafts and support favorable outcomes in pediatric and young adult recipients.

    View details for DOI 10.1097/TP.0b013e3181f546af

    View details for Web of Science ID 000283650200011

    View details for PubMedID 20814356

  • Increased HLA-DR Expression on Tissue Eosinophils in Eosinophilic Esophagitis JOURNAL OF PEDIATRIC GASTROENTEROLOGY AND NUTRITION Patel, A. J., Fuentebella, J., Gernez, Y., Nguyen, T., Bass, D., Berquist, W., Cox, K., Sibley, E., Kerner, J., Nadeau, K. 2010; 51 (3): 290-294

    Abstract

    The aim of the study was to investigate whether eosinophils have increased human leukocyte antigen (HLA)-DR expression in subjects with eosinophilic esophagitis (EoE) compared with controls.Patients who were undergoing an upper endoscopy with biopsies for suspected gastroesophageal reflux disease (GERD) or EoE at Lucile Packard Children's Hospital were enrolled. In total, the blood and tissue samples of 10 healthy controls (HC), 11 subjects with GERD, and 10 with EoE were studied. Multiple tissue staining to identify eosinophils (via eosinophil cationic protein-clone EG2) and major histocompatibility complex class II cell surface receptors (via HLA-DR) was performed via immunohistochemistry. The peripheral blood was analyzed using flow cytometry to detect eosinophil HLA-DR expression among these subjects.In the tissue, a greater proportion of eosinophils expressed HLA-DR among the subjects with EoE (mean 0.83 +/- 0.14, n = 9) relative to those with GERD (mean 0.18 +/- 0.19, n = 8, P < 0.01) and HC (mean 0.18 +/- 0.13, n = 6, P < 0.01). In total, 6 participants (4 HC subjects and 2 subjects with GERD) did not have any eosinophils identified on tissue staining and were unable to be included in the present statistical analysis. In the blood, there was no statistically significant difference in eosinophil HLA-DR expression among HC subjects (mean 415 +/- 217, n = 6), subjects with GERD (mean 507 +/- 429, n = 2), and those with EoE (mean 334 +/- 181, n = 6).These data demonstrate that the eosinophils from the esophagus of subjects with EoE have increased HLA-DR expression within this tissue.

    View details for DOI 10.1097/MPG.0b013e3181e083e7

    View details for Web of Science ID 000281453500008

    View details for PubMedID 20639774

  • Increased Number of Regulatory T Cells in Children With Eosinophilic Esophagitis JOURNAL OF PEDIATRIC GASTROENTEROLOGY AND NUTRITION Fuentebella, J., Patel, A., Nguyen, T., Sanjanwala, B., Berquist, W., Kerner, J. A., Bass, D., Cox, K., Hurwitz, M., Huang, J., Nguyen, C., Quiros, J. a., Nadeau, K. 2010; 51 (3): 283-289

    Abstract

    There are limited data on the role of regulatory T cells (Treg) in the disease pathology of eosinophilic esophagitis (EoE). We tested the differences in Treg in subjects with EoE compared with those with gastroesophageal reflux disease (GERD) and healthy controls (HC).Pediatric patients evaluated by endoscopy were recruited for our study. Participants were categorized into 3 groups: EoE, GERD, and HC. RNA purified from esophageal biopsies were used for real-time quantitative polymerase chain reaction assays and tested for forkhead box P3 (FoxP3) mRNA expression. Treg were identified as CD4+CD25hiCD127lo cells in peripheral blood and as CD3+/FoxP3+cells in esophageal tissue.Forty-eight subjects were analyzed by real-time quantitative polymerase chain reaction: EoE (n = 33), GERD (n = 7), and HC (n = 8). FoxP3 expression was higher by up to 1.5-fold in the EoE group compared with the GERD and HC groups (P < 0.05). Protein levels of FoxP3 in blood and tissue were then investigated in 21 subjects: EoE (n = 10), GERD (n = 6), and HC (n = 5). The percentage of Treg and their subsets in peripheral blood were not significant between groups (P > 0.05). The amount of Treg in esophageal tissue was significantly greater in the EoE group (mean 10.7 CD3+/FoxP3+cells/high power field [HPF]) compared with the other groups (GERD, mean 1.7 CD3+/FoxP3+cells/HPF and HC, mean 1.6 CD3+/FoxP3+cells/HPF) (P < 0.05).We show that Treg are increased in esophageal tissue of EoE subjects compared with GERD and HC subjects. The present study illustrates another possible mechanism involved in EoE that implicates impairment of immune homeostasis.

    View details for DOI 10.1097/MPG.0b013e3181e0817b

    View details for Web of Science ID 000281453500007

    View details for PubMedID 20639775

  • Eotaxin and FGF enhance signaling through an extracellular signal-related kinase (ERK)-dependent pathway in the pathogenesis of Eosinophilic esophagitis. Allergy, asthma, and clinical immunology : official journal of the Canadian Society of Allergy and Clinical Immunology Huang, J. J., Joh, J. W., Fuentebella, J., Patel, A., Nguyen, T., Seki, S., Hoyte, L., Reshamwala, N., Nguyen, C., Quiros, A., Bass, D., Sibley, E., Berquist, W., Cox, K., Kerner, J., Nadeau, K. C. 2010; 6 (1): 25-?

    Abstract

    Eosinophilic esophagitis (EoE) is characterized by the inflammation of the esophagus and the infiltration of eosinophils into the esophagus, leading to symptoms such as dysphagia and stricture formation. Systemic immune indicators like eotaxin and fibroblast growth factor were evaluated for possible synergistic pathological effects. Moreover, blood cells, local tissue, and plasma from EoE and control subjects were studied to determine if the localized disease was associated with a systemic effect that correlated with presence of EoE disease.Real-time polymerase chain reaction from peripheral blood mononuclear cells (PBMC), immunohistochemistry from local esophageal biopsies, fluid assays on plasma, and fluorescence-activated cell sorting on peripheral blood cells from subjects were used to study the systemic immune indicators in newly diagnosed EoE (n = 35), treated EoE (n = 9), Gastroesophageal reflux disease (GERD) (n = 8), ulcerative colitis (n = 5), Crohn's disease (n = 5), and healthy controls (n = 8).Of the transcripts tested for possible immune indicators, we found extracellular signal-regulated kinase (ERK), Bcl-2, bFGF (basic fibroblast growth factor), and eotaxin levels were highly upregulated in PBMC and associated with disease presence of EoE. Increased FGF detected by immunohistochemistry in esophageal tissues and in PBMC was correlated with low levels of pro-apoptotic factors (Fas, Caspase 8) in PBMC from EoE subjects. Plasma-derived bFGF was shown to be the most elevated and most specific in EoE subjects in comparison to healthy controls and disease control subjects.We describe for the first time a possible mechanism by which increased FGF is associated with inhibiting apoptosis in local esophageal tissues of EoE subjects as compared to controls. Eotaxin and FGF signaling pathways share activation through the ERK pathway; together, they could act to increase eosinophil activation and prolong the half-life of eosinophils in local tissues of the esophagus in EoE subjects.

    View details for DOI 10.1186/1710-1492-6-25

    View details for PubMedID 20815913

  • Decreases in circulating CD4(+)CD25(hi)FOXP3(+) cells and increases in intragraft FOXP3(+) cells accompany allograft rejection in pediatric liver allograft recipients PEDIATRIC TRANSPLANTATION Stenard, F., Nguyen, C., Cox, K., Kambham, N., Umetsu, D. T., Krams, S. M., Esquivel, C. O., Martinez, O. M. 2009; 13 (1): 70-80

    Abstract

    We examined CD4(+)CD25(hi)FOXP3(+) cells Treg in children following liver transplantation and determined the relationship between Treg cell levels in the blood and in the graft. Peripheral blood was obtained from pediatric liver transplant patients at sequential time points: pre-transplant, one month, 3-4 months, 6-7 months, and 11-12 months post-transplant. PBMC were isolated, labeled for CD4, CD25 and FOXP3 expression and analyzed by flow cytometry for CD4(+)CD25(hi)FOXP3(+) cells. Sorted CD4(+)CD25(hi) cells were assessed for functional activity. Pretransplant blood levels of CD4(+)CD25(hi)FOXP3(+) Treg cells were not significantly different from post-transplant blood levels of CD4(+)CD25(hi)FOXP3(+) Treg cells. However, the blood levels of CD4(+)CD25(hi)FOXP3(+) Treg cells were significantly decreased during acute rejection compared with levels when graft function was stable. Immunohistochemistry revealed that FOXP3(+) cells were increased in the portal region of livers with histopathologic evidence of acute graft rejection compared with livers without evidence of rejection and were localized primarily within the inflammatory infiltrate. These data indicate that Treg cells are found at the site of allograft rejection and may play a role in regulation of alloreactivity. Moreover, monitoring peripheral CD4(+)CD25(hi)FOXP3(+) Treg cell levels may be useful in improving the post-transplant management of pediatric liver allograft recipients.

    View details for DOI 10.1111/j.1399-3046.2008.00917.x

    View details for Web of Science ID 000262285400012

    View details for PubMedID 18331536

  • Long-term treatment of primary sclerosing cholangitis in children with oral vancomycin: An immunomodulating antibiotic JOURNAL OF PEDIATRIC GASTROENTEROLOGY AND NUTRITION Davies, Y. K., Cox, K. M., Abdullah, B. A., Safta, A., Terry, A. B., Cox, K. L. 2008; 47 (1): 61-67

    Abstract

    Primary sclerosing cholangitis is a rare chronic cholestatic condition of unknown etiology, frequently associated with inflammatory bowel disease and characterized by diffuse fibrosing and inflammatory destruction of the intra- and/or extrahepatic biliary duct system.The study involved 14 children with primary sclerosing cholangitis confirmed by either liver biopsy, endoscopic retrograde cholangiopancreatography, and/or magnetic resonance cholangiogram. In each of the 14 cases, liver histology showed characteristic features consistent with primary sclerosing cholangitis. Eleven children had intrahepatic biliary beading and strictures (6 by endoscopic retrograde cholangiopancreatography; 5 by magnetic resonance cholangiogram). Biochemical tests of liver function including alanine aminotransferase, aspartate aminotransferase, and gamma-glutamyl transpeptidase and the erythrocyte sedimentation rate were elevated for a mean 17 +/- 22 months before vancomycin treatment was initiated. All of the patients were shown to have inflammatory bowel disease histologically; 13 of those patients had clinical evidence of colitis. Oral vancomycin was given to all 14 patients.All 14 patients showed improvement in their alanine aminotransferase (P = 0.007), gamma-glutamyl transpeptidase (P = 0.005), erythrocyte sedimentation rate (P = 0.008), and clinical symptoms with oral vancomycin treatment. There was less improvement noted in the patients with cirrhosis when compared with the patients without cirrhosis.Before this study, there has not been an effective long-term treatment for sclerosing cholangitis to prevent the usual progression of this disease to cirrhosis. This study showed that oral vancomycin could be an effective long-term treatment of sclerosing cholangitis in children, especially those without cirrhosis.

    View details for Web of Science ID 000257179500010

    View details for PubMedID 18607270

  • Non-adherence to post-transplant care: Prevalence, risk factors and outcomes in adolescent liver transplant recipients PEDIATRIC TRANSPLANTATION Berquist, R. K., Berquist, W. E., Esquivel, C. O., Cox, K. L., Wayman, K. I., Litt, I. F. 2008; 12 (2): 194-200

    Abstract

    This study examined the prevalence, demographic variables and adverse outcomes associated with non-adherence to post-transplant care in adolescent liver transplant recipients. We conducted a retrospective chart review of 111 adolescent patients (age 12-21 yr) greater than six months post-transplantation and defined non-adherence as not taking the immunosuppressive(s) or not attending any clinic visit in 2005. Fifty subjects (45.0%) were non-adherent and 61 (55.0%) were adherent. Twenty percent of the subjects did not attend clinic and 10.9% did not complete laboratory tests. Non-adherence was significantly associated with fewer completed laboratory tests (p < 0.0001), single parent status (p < 0.0186), and older age and greater years post-transplantation by both univariate and multivariate analyses (p < 0.008, p < 0.0141 and p < 0.0012, p < 0.0174, respectively). Non-adherence to medication was significantly associated with a rejection episode in 31 patients (p < 0.0069) but not in the subgroup of seven patients who stopped their immunosuppression completely. Non-adherence to post-transplant care is a prevalent problem in adolescents particularly of an older age and greater years post-transplantation. Rejection was a significant consequence of medication non-adherence except in a subgroup with presumed graft tolerance who discontinued their immunosuppression. These results emphasize the need for strict monitoring of adherence to post-transplant care to improve long-term survival and quality of life in adolescent transplant patients.

    View details for DOI 10.1111/j.1399-3046.2007.00809.x

    View details for Web of Science ID 000253637400013

    View details for PubMedID 18307668

  • Outcomes of transplantation in children with primary hepatic malignancy PEDIATRIC TRANSPLANTATION Beaunoyer, M., Vanatta, J. M., Oyihara, M., Strichartz, D., Dahl, G., Berquist, W. E., Castillo, R. O., Cox, K. L., Esquivel, C. O. 2007; 11 (6): 655-660

    Abstract

    HBL and HCC are the most common hepatic malignancies in children. The role of OLT in children with HCC is still a matter of debate. The aim of this study was to review our experience of OLT for HCC. Medical records of patients (<18 yr) who underwent OLT for HCC were reviewed and compared to children who underwent OLT for HBL and for indications other than malignancy. There were 25 patients: HCC (10 cases) and HBL (15 cases). The actuarial patient survival for HCC at one and five yr was 100% and 83.3%, for the HBL group the survival was 86.7% at both one and five yr, and for indications (n=377) other than malignancy the patient survival for pediatric OLT at our center was 87.7% and 84.7% at one and five yr, respectively. The actuarial recurrence free survival at five yr was 83.3% for HCC and 66.8% for HBL. In conclusion, OLT is a good therapeutic modality for children with HCC and HBL.

    View details for DOI 10.1111/j.1399-3046.2007.00751.x

    View details for Web of Science ID 000249004000015

    View details for PubMedID 17663690

  • Pediatric intestinal transplantation at Packard children's hospital/Stanford University medical center: Report of a four-year experience TRANSPLANTATION PROCEEDINGS Castillo, R. O., Zarge, R., Cox, K., Strichartz, D., Berquist, W., Bonham, C. A., Esquivel, C. O. 2006; 38 (6): 1716-1717

    Abstract

    We report a 4-year experience of a new program in pediatric intestinal transplantation. Among 50 children referred for evaluation, 27 were listed for transplantation. Two children originally listed for combined liver/small bowel transplant were changed to isolated intestinal transplant as rehabilitation efforts resulted in full recovery of hepatic function. Eighteen children received 18 grafts: 12 liver/intestine, 5 isolated intestine, and 1 multivisceral. Mean age at transplant was 3.6 year with 75% of patients aged 0 to 2 years. Five listed children died while waiting and four were still on the list. Immunotherapy included antithymocyte globulin induction and tacrolimus, sirolimus, and prednisone maintenance. At 1 year, patient and graft survivals were 75% and 67%, respectively. For isolated intestine, 1 year survivals were 100% and 75%, while for combined liver/intestine, they were 71% for both. Enteral autonomy is 100% with total parenteral nutrition stopping by 35.8 days (mean). We had two patients develop posttransplant lymphoproliferative disorder and three, exfoliative rejection, one of whom recovered completely. In conclusion, our program in pediatric intestinal transplantation has become well established with a high proportion of smaller/younger children receiving grafts. Outcomes achieved levels expected based on The Intestinal Transplant Registry and UNOS criteria, which were better than expected for isolated intestinal transplants and achievement of enteral autonomy.

    View details for DOI 10.1016/j.transproceed.2006.05.038

    View details for Web of Science ID 000240051700022

    View details for PubMedID 16908259

  • Adolescent non-adherence: Prevalence and consequences in liver transplant recipients PEDIATRIC TRANSPLANTATION Berquist, R. K., Berquist, W. E., Esquivel, C. O., Cox, K. L., Wayman, K. I., Litt, I. F. 2006; 10 (3): 304-310

    Abstract

    Few studies have examined the prevalence, demographic variables and adverse consequences associated with non-adherence to immunosuppressive therapy in the adolescent liver transplant population. Our hypothesis is that a significant proportion of adolescent liver transplant recipients exhibit non-adherence to medical regimens and that certain demographic and medical condition-related characteristics can be identified as potential predictors of non-adherent behavior. Furthermore, non-adherence leads to a greater incidence of morbidity and mortality in this population as compared with the adherent subset of adolescent patients. We reviewed the charts of 97 patients from 1987 to 2002 who by December of 2002 had survived at least 1 yr post-transplant and were followed by the Pediatric Liver Transplant Service at any point during their adolescent period (ages of 12-21). Non-adherence was defined as documentation of a report of non-adherence by a patient, parent or healthcare provider that was recorded in the patient's legal medical record. Descriptive statistics were used to determine the prevalence, demographic variables and adverse outcomes associated with non-adherence to immunosuppressive therapy. Categorical variables were analyzed using the chi-square test or the Fisher exact probability test. The unpaired Student's t-test was used to analyze the continuous variable of age at transplant. Using the inclusion criteria, a total of 97 patients represented the study sample of whom 37 subjects (38.1%) were defined as non-adherent and 60 (61.8%) were adherent. Non-adherent subjects were more likely to be female, older (>18 yr) and from a single-parent household. There was no significant difference in immunosuppressive regimen between non-adherent and adherent patients. Non-adherence was significantly (p<0.025) associated with lower socioeconomic status (SES), older age at transplant (p<0.005, 95% CI: -5.5 to -.99, Student's t-test) and episodes of late acute rejection (p<.001). Non-adherence was also significantly associated with re-transplantation and death secondary to chronic rejection by the Fisher exact test (p<0.006 and p<0.05, respectively). Non-adherence to immunosuppressive therapy is a prevalent problem that is correlated with certain demographic and medical condition-related risk factors and more frequent adverse consequences in the adolescent liver transplant population. The greater incidence of late acute rejection, death and re-transplantation owing to chronic rejection in non-adherent patients suggests that non-adherence is significantly associated with an increased risk of morbidity and mortality. Further investigation to identify patients at greatest risk for non-adherence is necessary to design the most effective intervention to increase patient survival and well being.

    View details for DOI 10.1111/j.1399-3046.2005.00451.x

    View details for Web of Science ID 000237096700007

    View details for PubMedID 16677353

  • Improved pain management in pediatric postoperative liver transplant patients using parental education and non-pharmacologic interventions PEDIATRIC TRANSPLANTATION Sharek, P. J., Wayman, K., Lin, E., Strichartz, D., Sentivany-Collins, S., Good, J., Esquivel, C., Brown, M., Cox, K. 2006; 10 (2): 172-177

    Abstract

    A pain management intervention, consisting of pretransplant parental education and support, pre- and postoperative behavioral pediatrics consultation, postoperative physical and occupational therapy consultation, and implementation of non-pharmacologic pain management strategies, was introduced to all pediatrics patients receiving liver transplants at Lucile Packard Children's Hospital beginning August 2001. Children receiving transplants pre-intervention (May, 2000 to February, 2001) and post-intervention (August, 2001 to March, 2002) were compared using pain scores, parent perception of pain ratings, length of stay, ventilator days, total cost, and opioid use. A total of 27 children were evaluated (13 historical control, 14 intervention). The two populations did not differ on age at transplant (mean age 53.8 vs. 63.6 months), sex (46.1% vs. 50% male), ethnicity (53.8% vs. 57.1% white, non-Hispanic) weight at transplant (17.5 vs. 24.7 kg), percent with biliary atresia as the primary reason for transplant (42.9% vs. 69.2%), percent with status 1 transplant listing score (38.5% vs. 50.0%), or public insurance status (30.8 vs. 57.2% with Medicaid). No differences were found in mean pediatric intensive care unit (PICU) postoperative length of stay (6.7 vs. 5.3 days), total postoperative length of stay (17.5 vs. 17.5 days), total inpatient length of stay (27.0 vs. 24.4 days), time to extubation (30 vs. 24.3 h), total cost (dollar 147,983 vs. dollar 157,882) or opioid use through postoperative day (POD) 6 (0.24 vs. 0.25 mg/kg/day morphine equivalent). A decrease in mean pain score between POD 0 and 6 (2.82 vs. 2.12; p = 0.047), a decrease in mean parental pain perception score (3.1 vs. 2.1; p = 0.001), and an increase in number of pain assessments per 12 h shift (3.43 vs. 6.79; p < 0.005) were seen. A comprehensive non-pharmacologic postoperative pain management program in children receiving a liver transplant was associated with decreased pain scores, improved parent perception of pain, and an increased number of pain assessments per 12 h shift. No increases in lengths of stay (PICU, postoperative, total), time to extubation, or total cost were found.

    View details for DOI 10.1111/j.1399-3046.2005.00438.x

    View details for Web of Science ID 000236026400011

    View details for PubMedID 16573603

  • Hepatic infantile hemangioendothelioma with unusual manifestations JOURNAL OF PEDIATRIC GASTROENTEROLOGY AND NUTRITION Burtelow, M., Garcia, T., Lucile, S., Cox, K., Berquist, W., Kemer, J. 2006; 42 (1): 109-113

    View details for Web of Science ID 000234437900024

    View details for PubMedID 16385264

  • Complete immunosuppressive withdrawal as a uniform approach to post-transplant lymphoproliferative disease in pediatric liver transplantation PEDIATRIC TRANSPLANTATION Hurwitz, M., Desai, D. M., Cox, K. L., Berquist, W. E., Esquivel, C. O., Millan, M. T. 2004; 8 (3): 267-272

    Abstract

    Epstein-Barr virus (EBV)-associated post-transplant lymphoproliferative disease (PTLD) in pediatric liver transplant recipients is associated with a high mortality (up to 60%) and the younger age groups, who are predominantly EBV-naïve, are at highest risk for development of this disease. The aim of this study is to assess, in this high-risk group, patient outcome and graft loss to rejection when complete withdrawal of immunosuppressive agents (IMS) is instituted as the mainstay of treatment in addition to the use of standard therapy. A retrospective analysis of 335 pediatric patients whose liver transplants were performed by our team between September 1988 and September 2002, was carried out through review of computer records, database and patient charts. Fifty patients developed either EBV or PTLD; 80% were < or =2 yr of age. Of these 50 patients, 19 had a positive tissue diagnosis for PTLD and 31 were diagnosed with EBV infection, 14 of whom had positive tissue for EBV. Fifty-eight percent of patients who developed PTLD and 51.6% of patients with EBV received antibody for induction or treatment of rejection prior to onset of disease. Forty-six patients (92%) received post-transplant antiviral prophylaxis with ganciclovir or acyclovir. Antiviral treatment included ganciclovir in 76%, acyclovir in 20% and Cytogam (in addition to one of the former agents) in 44%. In those with PTLD, treatment included chemotherapy (n = 1), Rituximab (n = 2), and ocular radiation (n = 1). IMS was stopped in all patients with PTLD and in 19 with EBV infection and was held as long as there was no allograft rejection. Eight patients have remained off IMS for a mean of 1535.5 +/- 623 days. Of the 21 patients who were restarted on IMS for acute rejection, 18 responded to steroids and/or reinstitution of low-dose calcineurin inhibitors. The mean time to rejection while off IMS in this group was 107.43 +/- 140 days (range: 7-476). Two patients were re-transplanted for chronic rejection; one had chronic rejection that existed prior to discontinuing IMS. The mortality rate in our series was 31.6% in those with PTLD and 6% in those with EBV disease. The cause of death was related to PTLD or sepsis in all cases; no deaths were due to graft loss from acute or chronic rejection. PTLD is associated with high mortality in the pediatric population. Based on this report, we advocate aggressive management of PTLD that is composed of early cessation of IMS, the use of antiviral therapy, and chemotherapy when indicated. Episodes of rejection that occur after stopping IMS can be successfully treated with standard therapy without graft loss to acute rejection.

    View details for Web of Science ID 000221693200014

    View details for PubMedID 15176965

  • One hundred percent patient and kidney allograft survival with simultaneous liver and kidney transplantation in infants with primary hyperoxaluria: A single-center experience TRANSPLANTATION Millan, M. T., Berquist, W. E., So, S. K., Sarwal, M. M., Wayman, K. I., Cox, K. L., Filler, G., Salvatierra, O., Esquivel, C. O. 2003; 76 (10): 1458-1463

    Abstract

    Combined liver-kidney transplantation is the definitive treatment for end-stage renal disease caused by primary hyperoxaluria type I (PH1). The infantile form is characterized by renal failure early in life, advanced systemic oxalosis, and a formidable mortality rate. Although others have reported on overall results of transplantation for PH1 covering a wide age spectrum, none has specifically addressed the high-risk infantile form of the disease.Six infants with PH1 underwent simultaneous liver-kidney transplantation at our center between May 1994 and August 1998. Diagnosis was made at 5.2+/-3.3 months of age, they were on dialysis for 11.8+/-2.3 months, and they underwent transplantation at 14.8+/-3.0 months of age when they weighed 10.6+/-1.7 kg.At a mean follow-up of 6.4+/-1.7 years (range, 3.9-8.1 years), we report 100% patient and kidney allograft survival. There were no cases of acute tubular necrosis. Long-term kidney allograft function remained stable in all patients, with serum creatinine values of less than 1.1 mg/dL and a mean creatinine clearance of 99 mL/min/1.73 m2 at follow-up. Those who received combined hemodialysis and peritoneal dialysis pretransplant had lower posttransplant urinary oxalate values than those receiving peritoneal dialysis alone. There was improvement in growth and psychomotor and mental developmental scores after transplantation.Combined liver-kidney transplantation for the infantile presentation of PH1 is associated with excellent outcome when the approach includes early diagnosis and early combined transplantation, aggressive pretransplant dialysis, and avoidance of posttransplant renal dysfunction.

    View details for DOI 10.1097/01.TP.0000084203.76110.AC

    View details for Web of Science ID 000186833400014

    View details for PubMedID 14657686

  • Identification of Epstein-Barr virus-specific CD8(+) T lymphocytes in the circulation of pediatric transplant recipients TRANSPLANTATION Falco, D. A., Nepomuceno, R. R., Krams, S. M., Lee, P. P., DAVIS, M. M., Salvatierra, O., Alexander, S. R., Esquivel, C. O., Cox, K. L., Frankel, L. R., Martinez, O. M. 2002; 74 (4): 501-510

    Abstract

    Pediatric transplant recipients are at increased risk for Epstein Barr virus (EBV)-related B cell lymphomas. In healthy individuals, the expansion of EBV-infected B cells is controlled by CD8+ cytotoxic T cells. However, immunosuppressive therapy may compromise antiviral immunity. We identified and determined the frequency of EBV-specific T cells in the peripheral blood of pediatric transplant recipients.HLA-B*0801 and HLA-A*0201 tetramers folded with immunodominant EBV peptides were used to detect EBV-specific CD8+ T cells by flow cytometry in peripheral blood mononuclear cells from 24 pediatric liver and kidney transplant recipients. The expression of CD38 and CD45RO on EBV-specific, tetramer-binding cells was also examined in a subset of patients by immunofluorescent staining and flow cytometry.Tetramer-binding CD8+ T cells were identified in 21 of 24 transplant recipients. EBV-specific CD8+ T cells were detected as early as 4 weeks after transplant in EBV seronegative patients receiving an organ from an EBV seropositive donor. The frequencies (expressed as a percentage of the CD8+ T cells) of the tetramer-binding cells were HLA-B8-RAKFKQLL (BZLF1 lytic antigen peptide) tetramer, range=0.96 to 3.94%; HLA-B8-FLRGRAYGL (EBNA3A latent antigen peptide) tetramer, range=0.03 to 0.59%; and HLA-A2-GLCTLVAML (BMLF1 lytic antigen peptide) tetramer, range=0.06 to 0.76%. The majority of tetramer reactive cells displayed an activated/memory phenotype.Pediatric transplant recipients receiving immunosuppression can generate EBV-specific CD8+ T cells. Phenotypic and functional analysis of tetramer cells may prove useful in defining and monitoring EBV infection in the posttransplant patient.

    View details for Web of Science ID 000177808600012

    View details for PubMedID 12352909

  • Thirteen years' experience in pediatric liver transplantation: Differences between tacrolimus and cyclosporine TRANSPLANTATION PROCEEDINGS Zajicek, A., Esquivel, C., MILLAN, M., Cox, K., Berquist, R., Berquist, W. 2002; 34 (5): 1976-1978

    View details for Web of Science ID 000177369700254

    View details for PubMedID 12176653

  • Gastrointestinal dysfunction associated with syringomyelia and hydromyelia JOURNAL OF PEDIATRIC GASTROENTEROLOGY AND NUTRITION Garcia-Careaga, M., Cox, K. M., Blankenberg, F., Cox, K. L. 2000; 31 (1): 71-75

    View details for Web of Science ID 000087924200016

    View details for PubMedID 10896075

  • Increased dosage requirement and rejection after neoral conversion in pediatric liver transplant patients TRANSPLANTATION PROCEEDINGS Cao, S., Cox, K. L., Berquist, W., So, S., Concepcion, W., Monge, H., Esquivel, C. O. 1998; 30 (8): 4322-4324

    View details for Web of Science ID 000077593000129

    View details for PubMedID 9865373

  • Oral vancomycin: Treatment of primary sclerosing cholangitis in children with inflammatory bowel disease JOURNAL OF PEDIATRIC GASTROENTEROLOGY AND NUTRITION Cox, K. L., Cox, K. M. 1998; 27 (5): 580-583

    View details for Web of Science ID 000076693500015

    View details for PubMedID 9822326

  • Liver transplantation at Stanford University Medical Center. Clinical transplants Millan, M. T., Keeffe, E. B., Berquist, W. E., Castillo, R. O., Cox, K. L., Garcia, G., Imperial, J. C., Monge, H., So, S. K., Esquivel, C. O. 1998: 287-296

    Abstract

    Because of the unique demographics of our patient population, we have had the opportunity to dedicate further studies of the management of hepatitis B and hepatitis C. We have experienced a very low HBV recurrence rate with the use of HBIG in patients transplanted for hepatitis B. Investigations, including the use of new antiviral agents, and the development of approaches to minimize or abrogate disease recurrence such as lower levels of immunosuppression are ongoing. Using a standardized approach to the proper evaluation and selection of patients for liver transplantation with alcoholic liver disease or other liver diseases with coexistent alcohol abuse, we report favorable long-term results in these patients. We have reviewed our results and our approach to the management of EBV and posttransplant lymphoproliferative disorder. There is a firm commitment in our laboratories and outpatient clinics to the investigation of disease prevention, reliable detection and screening methods, and treatment modalities for EBV-related disease. We have addressed specific technical considerations to pediatric liver transplant and have discussed unique aspects of postoperative management in these patients. One-third of the transplants performed at Stanford are in children, 42% of whom are less than one year old. Results with our pediatric transplant recipients compare favorably with those of our adult recipients with patient and graft survival rates approaching 90% at one year and exceeding 80% at 46 months for both groups. As a response to the limited organ supply, we have extended our criteria for suitable donors. Most notably, we have utilized older donors and grafts with significant microsteatosis and have observed good results with these grafts as long as ischemia time is minimized. We have also successfully used reduced size grafts for our pediatric patients with good results and are continuing to expand the use of living-related partial grafts and split allografts.

    View details for PubMedID 10503106

  • Epstein-Barr virus lymphoproliferative disorders after liver transplantation. Clinics in liver disease Cao, S., Cox, K. L. 1997; 1 (2): 453-?

    Abstract

    Post-transplant lymphoproliferative disorders (PTLD) represent a spectrum of histological and immunological abnormalities, ranging from benign polyclonal B-cell hyperplasia to monoclonal malignant lymphoma. The important role of Epstein-Barr virus (EBV) in PTLD in liver transplant patients, particularly in pediatric recipients, is reviewed. Understanding the risks of EBV infection, the clinical presentations and diagnosis of PTLD, and its pathophysiology are crucial to the management of these disorders. Current treatment methods have resulted in better outcomes of these disorders, which in the past were uniformly fatal.

    View details for PubMedID 15562578

Conference Proceedings


  • Significance of detecting Epstein-Barr-Specific sequences in the peripheral blood of asymptomatic pediatric liver transplant recipients Krieger, N. R., Martinez, O. M., Krams, S. M., Cox, K., So, S., Esquivel, C. O. JOHN WILEY & SONS INC. 2000: 62-66

    Abstract

    Pediatric allograft recipients are at increased risk for Epstein-Barr virus (EBV)-associated illnesses. The early identification and diagnosis of EBV-associated disorders is critical because disease progression can often be curtailed by modification of immunosuppression. We have previously shown that detection of EBV-specific sequences in the circulation by polymerase chain reaction (PCR) correlated well with the clinical symptoms of EBV infection. The purpose of the current study is to determine the significance of detecting EBV-specific sequences by PCR in asymptomatic pediatric liver transplant recipients. Peripheral-blood DNA was analyzed for the EBV genes, coding from the nuclear antigen 1 (EBNA-1) and the viral capsid antigen (gp220) by PCR. Samples from asymptomatic pediatric liver transplant recipients were analyzed from the immediate postoperative period and at 2- to 4-month intervals thereafter. We followed up 13 of these asymptomatic recipients who tested positive for EBV compared with 7 asymptomatic recipients who tested negative for EBV during the early posttransplantation period. Follow-up ranged from 1.5 to 4 years posttransplantation. Nine patients (69%) initially positive for EBV and asymptomatic ultimately developed symptoms of EBV infection, including fever, lymphadenopathy, rash, respiratory and gastrointestinal symptoms, and/or hepatitis. Five of these patients (56%) went on to develop posttransplant lymphoproliferative disorder based on histological examination of biopsied tissue and immunohistochemical identification of the EBV antigen/DNA in tissue. This is the first report suggesting that detection of EBV-specific sequences in the absence of symptoms may herald impending EBV-associated disorders. Thus, routine monitoring for circulating EBV sequences in asymptomatic recipients may be useful in the early identification of those at risk for developing EBV-associated disease and its ultimate prevention.

    View details for Web of Science ID 000085673100008

    View details for PubMedID 10648579

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