Orthotopic liver transplantation for autoimmune hepatitis and cryptogenic chronic hepatitis in children.

BACKGROUND: Autoimmune hepatitis (AIH) and cryptogenic chronic hepatitis (CCH) are important causes of liver failure in children, frequently necessitating orthotopic liver transplantation (OLT). The aim of this study is to review disease progression and potential differences between subgroups of children with AIH and CCH. METHODS: The medical records of 65 children diagnosed with AIH or CCH between 1980 and 1998 were evaluated. RESULTS: The median age at presentation was 9 years, 8 months (range 4 months-19 years), and the median follow-up period was 8 years (range 3 months-18 years, 10 months). Forty-one patients (63%) were female. Twenty-eight patients were Hispanic, 28 were Caucasian, 8 were African-American, and 1 was Asian. Forty-three patients (66%) were diagnosed with type 1 AIH, 8 (12%) with type 2 AIH, and 14 (22%) with CCH. Forty patients (62%) underwent OLT (51% of those with type 1 AIH, 75% of those with type 2 AIH, and 86% of those with CCH). Thirteen (33%) of the transplanted patients experienced disease recurrence. African-American patients experienced a significantly higher rate of disease recurrence post-OLT than did Hispanic patients. Seven patients (11%) died, two without OLT, and five posttransplantation. CONCLUSIONS: AIH and CCH frequently necessitate OLT in children. CCH is a more aggressive disease than Type 1 AIH among children with these disorders. Ethnicity influences the rate of disease recurrence after liver transplantation.

Factors influencing reflectance spectrophotometric measurements of gastrointestinal mucosal blood flow.

Although the technique of endoscopic reflectance spectrophotometry has been applied in clinical studies, factors that modify the reproducibility of measurements have not been assessed systematically. To determine the limitations of the technique, measurements were made while endoscopic light intensity, systemic oxygen saturation, and orientation of the measuring probe were varied. The effects of hemorrhagic hypotension and exposure of the mucosa to 10% dextrose were also studied. When a large number (n = 480) of measurements in the human colon were considered, endoscopic light significantly decreased the index of oxygen saturation (ISO2) and increased the index of hemoglobin concentration (IHB). The decrease in ISO2, however, was small and unlikely to be of clinical importance despite being statistically significant. In one subject with chronic lung disease and baseline hypoxemia, administration of supplemental oxygen significantly increased oxygen saturation at the finger tip as measured by an oximeter and ISO2 of the buccal mucosa as measured by reflectance spectrophotometry. Varying the angle between the measuring probe and the gastric mucosa in rats from 90 degrees to 60 degrees did not affect ISO2 or IHB measurements. At 45 degrees, however, IHB but not ISO2 was significantly increased. Ischemia subsequent to induction of hemorrhagic hypotension and hyperemia induced by administration of 10% dextrose could be demonstrated reproducibly. We conclude that by lowering the intensity of endoscopic light and providing supplemental oxygen, errors in the measurement of IHB and ISO2, respectively, can be minimized. Minor deviations from the perpendicular orientation do not significantly affect ISO2 and IHB measurements. Attention to these details enhances the accuracy of endoscopic reflectance spectrophotometric recordings of ISO2 and IHB in clinical studies.

The role of orthotopic liver transplantation in the treatment of ornithine transcarbamylase deficiency.

The purpose of this study was to combine our clinical experience with a review of the literature to determine the value of orthotopic liver transplantation in the treatment of both boys and girls with ornithine transcarbamylase deficiency. Three boys younger than 1 year of age with symptomatic ornithine transcarbamylase deficiency (median age, 116 days; range, 40 to 223 days) underwent orthotopic liver transplantation. The patients' growth, developmental progress, ammonia levels, and amino acid levels were analyzed pre- and post-liver transplantation. The clinical courses of the respective patients and the treatment modalities used were compared with published reports from 1978 through 1997. The median follow-up period in these 3 patients was 3.2 years (range, 9 months to 5.2 years). Orthotopic liver transplantation restored normal urea production and stabilized ammonia levels within 24 hours of surgery (median serum ammonia level 24 hours post-liver replacement, 43 micromol/L; range, 30 to 66 micromol/L). After liver replacement, arginine synthesis was normalized; however, plasma citrulline levels remained less than normal in all patients. Linear growth was evaluated in all 3 patients at the time of the most recent follow-up; median z scores for patient height and weight were -2.16 and -1.16, respectively. Standardized intelligence tests showed that 2 of the 3 patients continue to perform at age-appropriate levels. The third child was developmentally delayed pretransplantation at 4 months of age on presentation and continues to perform in a below-average fashion. Orthotopic liver transplantation results in the restoration of normal urea production and serum ammonia levels in the boy suffering from symptomatic ornithine transcarbamylase deficiency. Serum arginine, but not citrulline, levels are normalized, probably because of the persistent intestinal mucosa defect. Patient growth is similar to that in infants undergoing liver transplantation for other causes. When liver transplantation is performed before cognitive impairment occurs, intellectual development is normal, because the risk of additional episodes of hyperammonemia is elevated.