Bradley H. Kessler

Nitric oxide and inflammatory bowel disease: evidence for local intestinal production in children with active colonic disease.

BACKGROUND Active colitis in patients with inflammatory bowel disease is associated with mucosal vasodilation, increased intestinal permeability and abnormal colonic motility. Nitric oxide is a messenger molecule with many functions, including regulation of local blood flow, vasomotor tone, and inflammation. Increased nitric oxide production and inducible nitric oxide synthase activity have been demonstrated in experimental models of colitis. This study was designed to determine the relationship between nitric oxide production and colonic inflammation in children with active colitis and in control subjects and whether expression of inducible nitric oxide synthase protein is demonstrable in the intestinal epithelium of these patients. METHODS Nitrate + nitrite were measured in urine, stool, and plasma using the Griess assay. Expression of inducible nitric oxide synthase protein in intestinal tissue was determined by immunohistochemical localization. RESULTS Urinary nitrate + nitrite levels were not significantly different in patients and control subjects. In contrast, stool and plasma nitrate + nitrite concentrations were significantly higher in children with inflammatory bowel disease compared with levels in control children (stool: 162.4 +/- 31.0 mumol/l versus 77.2 +/- 22.1 mumol/l; plasma: 65.2 +/- 9.9 mumol/l versus 38.1 +/- 6.6 mumol/L; p < 0.05). Stool nitrate + nitrite levels significantly correlated with plasma values. Immunohistochemical staining of colonic tissue from children with inflammatory bowel disease demonstrated inducible nitric oxide synthase protein located exclusively in epithelial cells. CONCLUSION Increased nitric oxide production and enhanced intestinal epithelial cell expression of inducible nitric oxide synthase protein are associated with active colonic inflammation.

FOLLOW UP EXPERIENCE IN PEDIATRIC LIVER TRANSPLANTATION IN AN ACADEMIC, NON-TRANSPLANT BASED GASTROENTEROLOGY GROUP: 143

As pediatric liver transplantation has become relatively common since the early 1980s, most long-term follow-up care has shifted from transplant centers to the pediatric gastroenterologists at referring institutions. We reviewed our experience with 16 patients who have undergone liver transplantation at eight institutions from 1987 to 1996. Our initial follow-up visit took place at an average 4.1 months after the transplant. The mean duration of follow-up was 41 months. During this period 11 hospitalizations at the transplant center occured, including five that were to rule out lymphoma or post-transplant lymphoproliferative disease. At the Schneider Childrens Hospital, NY, USA, 158 outpatient visits were recorded. Forty-two hospitalizations occurred. Twenty of the hospital admissions were accounted for by two patients. Forty-nine outpatient/inpatient surgical or diagnostic procedures were performed, including 15 percutaneous liver biopsies. In only one biopsy was there a disagreement in the histologic diagnosis between our pathologist and the pathologist at the transplant center. In conclusion, comprehensive follow-up care can be provided by an academic hospital-based gastroenterology group in conjunction with a transplant center.

Graft-versus-host disease: gastrointestinal involvement with a rectovaginal fistula.

Bone marrow transplantation is an accepted form of treatment for aplastic anemia and end-stage hematological malignancies. Despite a satisfactory outcome in selected patients, more than one-half develop acute graft-versus-host disease (GVHD), characterized typically by involvement of the skin, liver, and gastrointestinal tract. We describe an unusual case in which a 10-year-old girl developed gastrointestinal symptoms as the only manifestation of GVHD. The patient presented with a rectovaginal fistula and had clinical, radiological, and histological features of gastrointestinal GVHD without evidence of liver or skin involvement.

Follow‐up experience in pediatric liver transplantation in an academic, non‐transplant‐based gastroenterology group

Abstract: As pediatric liver transplantation has become relatively common since the early 1980s, most long‐term follow‐up care has shifted from transplant centers to the pediatric gastroenterologists at referring institutions. We reviewed our experience with 16 patients who have undergone liver transplantation at eight institutions from 1987 to 1996. Our initial follow‐up visit took place at an average 4.1 months after the transplant. The mean duration of follow‐up was 41 months. During this period 11 hospitalizations at the transplant center occured, including five that were to rule out lymphoma or post‐transplant lymphoproliferative disease. At the Schneider Children’s Hospital, NY, USA, 158 outpatient visits were recorded. Forty‐two hospitalizations occured. Twenty of the hospital admissions were accounted for by two patients. Forty‐nine outpatient/inpatient surgical or diagnostic procedures were performed, including 15 percutaneous liver biopsies. In only one biopsy was there a disagreement in the histologic diagnosis between our pathologist and the pathologist at the transplant center. In conclusion, comprehensive follow‐up care can be provided by an academic hospital‐based gastroenterology group in conjunction with a transplant center.