Defects of bile acid synthesis in Zellweger's syndrome.

Abnormal mitochondrial structure and function have been documented in patients with Zellweger's syndrome (cerebrohepatorenal syndrome). In vitro studies have suggested that the formation of C24 bile acids (chenodeoxycholic acid and cholic acid) from C27 cholesterol requires mitochondrial oxidative clevage of the terminal three carbons of the side chain. Therefore, three patients with Zellweger's syndrome were examined for the presence of mitochondrial defects in bile acid synthesis. All three excreted excessive amounts of 3 alpha, 7 alpha-dihydroxy-5 beta-cholestan-26-oicacid, 3 alpha, 7 alpha, 12 alpha-trihydroxy-5 beta-cholestan-26-oic acid, and 3 alpha, 7 alpha, 12 alpha, 24 xi-tetrahydroxy-5 beta-cholestan-26-oic acid (varanic acid), precursors of chenodeoxycholic acid and cholic acid that have undergone only partial side chain oxidation. These findings give added support to the role of mitochondrial oxidative side chain cleavage in the overall scheme of bile acid synthesis.

Genetic analysis of patients with chronic active hepatitis.

21 patients with chronic active hapatitis (CAH) and their families were HL-A typed. HL-A8 was significantly increased in frequency. An apparent increased frequency of HL-A1 was shown to be secondary to the increased HL-A8 due to linkage disequilibrium. Genotype analysis revealed a striking increased frequency of homozygosity for HL-A8, 6 of 21 patients (28.5%) vs. 2.8% of controls. Two patients and one normal who were homozygous for both HL-A1 and HL-A8 were found to be homozygous for a mixed lymphocyte culture (MLC) determinant 8a. Homozygous 8a cells were used as test-stimulating cells in one-way MLC reactions to determine the frequency of the expression of the 8a determinant in 17 patients and 49 controls selected for HL-A type. 8a was found to be associated with 50% of HL-A8 haplotypes and was frequent in the patient and control populations of the same HL-A types. These data suggest that susceptibility to CAH is determined by homozygosity for a gene that is in linkage disequilibrium with HL-A8 and more closely associated with the HL-A second locus then with the locus for the major MLC determinant.

The metabolism of 3alpha, 7alpha, 12alpha-trihydorxy-5beta-cholestan-26-oic acid in two siblings with cholestasis due to intrahepatic bile duct anomalies. An apparent inborn error of cholic acid synthesis.

Studies were carried out in a family in which two children with cholestasis due to intrahepatic bile duct anomalies were shown to have increased amounts of the cholic acid precursor, 3alpha, 7alpha, 12alpha-trihydorxy-5beta-cholestan-26-oic acid (THCA). The metabolism of THCA was studied in one of these patients after an intravenous injection of (3H)THCA, and the cause of the increased amounts of THCA in this condition was found to be due to a metabolic defect in the conversion of this compound into cholic acid. A small amount of (3H)cholic acid was also identified after (3H)THCA administration, confirming that this metabolic defect was incomplete. Varanic acid (3alpha, 7alpha, 12alpha, 24xi-tetrahydorxy-5beta-cholestan-26-oic acid), a metabolite of THCA, could not be identified in either of these patients. By assuming that this compound would be conjugated and excreted if the metabolic block occurred after the formation of varanic acid, the defect in these patients appears to be due to a deficiency of a 24-hydroxylating enzyme system required to convert THCA into varanic acid. This condition appears to be transmitted in an autosomal recessive fashion, because the two affected patients were of opposite sex, and neither a normal sibling nor the two parents have increased amount of THCA in their bile.

Long-term complications of arteriohepatic dysplasia.

PURPOSE: It has been stated that arteriohepatic dysplasia is a form of biliary paucity with a good prognosis. We wished to determine the long-term morbidity and mortality associated with arteriohepatic dysplasia. PATIENTS AND METHODS: The charts of all patients with arteriohepatic dysplasia followed by the pediatric gastroenterologists of the University of Minnesota into adulthood were reviewed. RESULTS: Over the last 33 years, the pediatric gastroenterologists have followed 16 children with syndromic paucity, six of whom are now beyond age 18 years. Although five of six patients responded to medical therapy with improvement in their cholestasis and appeared stable clinically through childhood, five of six patients had complications of arteriohepatic dysplasia after age 16 years that resulted in severe morbidity (three) or death (two). These complications included hepatic failure (two), renal failure (one), cerebellar herniation (one), and hepatocellular carcinoma (one). In only one patient were symptoms of the complications present prior to the age of 18 years. CONCLUSION: As more patients with arteriohepatic dysplasia reach adulthood, it appears that this syndrome may be accompanied by long-term manifestations extending beyond childhood. It is important that physicians assuming management of these patients from pediatricians be aware that new abnormalities may appear without warning and that the hepatic disease may deteriorate despite apparent stability through childhood.

Immunodeficiency, xanthomas and obstructive liver disease.

Chronic obstructive liver disease and secondary hyperlipidemia developed in an immunodeficient boy. Sequential addition of cholestyramine and phenobarbital to his medical regimen, following an initial response to bile drainage, resulted in the disappearance of xanthomas and pruritus, and the restoration of normal serum concentrations of lipids and bile acids. This improvement may result from shifting the bile acid pool from the peripheral blood compartment to the enterohepatic circulation.

Liver allograft rejection. An analysis of the use of biopsy in determining outcome of rejection.

Two-hundred-seventy biopsy specimens from 47 patients undergoing liver transplants at the University of Minnesota were analyzed to determine if histological features could predict the eventual outcome of rejection episodes. Thirty-six patients (76.6%) rejected the transplant. Of these, five either suffered acute liver failure due to rejection (two cases) or developed chronic rejection (three cases). Features of significance in predicting such a bad outcome were arteritis, bile duct paucity, or simultaneous hepatocellular ballooning and hepatocellular dropout and necrosis. Other features, such as type and intensity of infiltrate, degree of bile duct damage, or simple presence of hepatocellular necrosis, were not predictive of outcome. Our conclusion is that biopsy is useful in predicting outcome. Since many of the histologic findings of predictive value were not present in initial pretreatment biopsy specimens, follow-up biopsies of patients being treated for rejection are recommended to assess efficacy of therapy.

Living-related intestinal transplantation: first report of a standardized surgical technique.

BACKGROUND: Intestinal transplants using cadaver donors have become an alternative to total parenteral nutrition (TPN) for the treatment of irreversible intestinal failure. Intestinal transplants using living-related donors have rarely been attempted, and the surgical technique has not been standardized. METHODS: We performed a living-related intestinal transplant for a paraplegic, 16-year-old boy with life-threatening TPN complications, including lack of vascular access, recurrent line infections, and intermittent liver dysfunction. RESULTS: A four antigen-matched donor (father) underwent resection of 200 cm of the ileum on a vascular pedicle comprising the ileocolic artery and vein. This resection left the donor with 300 cm of proximal small bowel, 20 cm of the most distal terminal ileum, the ileocecal valve, and all of the large intestine. The donor's ileocolic artery and vein were anastomosed to the recipient's infrarenal aorta and cava; bowel continuity was restored with an end-to-end anastomosis between the recipient's jejunum and the donor's ileum. Both donor and recipient had uneventful postoperative courses. Recipient maintenance immunosuppression has been with tacrolimus, mycophenolate mofetil, and prednisone. One year after transplant, urine methylmalonic acid indicates good vitamin B12 absorption in both the donor and recipient. The recipient has been completely off TPN since discharge (posttransplant day 21), has gained 20 kg, and has had no evidence of rejection, infection, or graft-versus-host disease. CONCLUSIONS: Intestinal transplants from living-related donors can be lifesaving for selected patients with chronic intestinal failure and can be done with minimal risk to the donor.

Positive effect of prophylactic total parenteral nutrition on long-term outcome of bone marrow transplantation.

In a randomized trial we studied the impact of providing total parenteral nutrition (TPN) to bone marrow transplant (BMT) patients during their cytoreductive therapy, and for 4 weeks following BMT, on 8 parameters of outcome. A total of 137 patients over 1 year of age and with normal nutritional status were randomized either to receive TPN starting one week prior to transplant or to receive hydration with a 5% dextrose solution containing electrolytes, minerals, trace elements, and vitamins. TPN was ultimately required by 40 of the 66 control patients when nutritional depletion was documented. Average total calorie and protein intake was significantly higher for the TPN group than for the control group. Minimum follow-up was 1 year and median was 2 years. Overall survival, time to relapse, and disease-free survival were significantly improved in the TPN group. Engraftment, duration of hospitalization, and incidences of acute and chronic graft-vs.-host disease and bacteremia were not different. Thus TPN during BMT had a positive effect on long-term outcome. Prophylactic nutritional therapy appears to be indicated even for well-nourished individuals during cytoreduction and BMT.

Active immunization with angiotensin I peptide analogue vaccines selectively reduces the pressor effects of exogenous angiotensin I in conscious rats.

1. Male, Sprague-Dawley rats were actively immunized with novel angiotensin vaccines, and their pressor responses to exogenous angiotensin I (AI) and angiotensin II (AII) were assessed in vivo. Serum antibody titres were also measured. 2. The most effective vaccine consisted of an AI analogue conjugated with a tetanus toxoid carrier protein and adjuvanted with aluminium hydroxide. When this vaccine was injected on days 0, 21 and 42, pressor responses to AI on day 63 were significantly inhibited (maximum, 8.9 fold shift), but responses to AII were unaffected. The anti-angiotensin antibody titre was increased 32,100 fold, and, uniquely, these antibodies also cross-reacted with angiotensinogen. 3. These findings indicate that active immunization against AI may be a useful approach for treating cardiovascular disorders involving the renin-angiotensin system.

Aspartylglucosaminuria: unique biochemical and ultrastructural characteristics.

The observation of vacuolated lymphocytes in a coarsely featured two year old female with hepatosplenomegaly, mitral insufficiency, and mild psychomotor retardation led to the first diagnosed case of aspartylglucosaminuria in the United States. Although physical characteristics and bone roentgenograms were consistent with a mucopolysaccharide disorder, analysis of the urine showed no mucopolysaccharide elevation. The chromatographic, enzymatic, and ultrastructural studies confirming the diagnosis are presented.

The pathologic spectrum of the nephropathy associated with alpha 1-antitrypsin deficiency.

To further define the clinicopathologic spectrum and pathogenetic mechanism of the nephropathy associated with alpha 1-antitrypsin (A1AT) deficiency, we evaluated renal specimens from 34 patients with chronic hepatic disease, including 20 with A1AT deficiency (study patients), and correlated these findings with urinalysis evaluation. Glomerular lesions were noted in 79% (15 of 19) of A1AT patients with the PiZZ phenotype, including seven with mesangio-capillary glomerulonephritis (MPGN and focal segmental MPGN), six with mesangial proliferative glomerulonephritis (Mes GN), one with diffuse endocapillary proliferative glomerulonephritis (DPGN), and one with focal segmental mesangial proliferative glomerulonephritis with segmental necrosis (FS Nec GN). One A1AT patient with the PiMZ phenotype did not demonstrate glomerular abnormalities. Focal segmental Mes GN was found in 43% (six of 14) of patients in an age-matched group with chronic hepatic failure unrelated to A1AT deficiency. In nine study patients, glomerular pathology was noted in the presence of a normal urinalysis. Immunofluorescence studies revealed the presence of immunoproteins and the A1AT protein isoelectric forms, PiM and PiZ, in the subendothelial region of glomerular basement membranes in A1AT patients with MPGN, Mes GN, and DPGN. Our results emphasize the heterogeneity of glomerular lesions associated with A1AT deficiency and hepatic disease and the relatively high incidence of MPGN in these children. The presence of abnormal PiZ protein in the subendothelial region of the glomerular basement membrane in A1AT patients with glomerulonephritis suggests a possible role for this protein in the pathogenesis of this lesion.

Hereditary tyrosinemia type I (chronic form): pathologic findings in the liver.

Hereditary tyrosinemia type I presents with either acute hepatic failure in the neonatal period or later in infancy with progressive liver dysfunction secondary to cirrhosis. The inevitably fatal outcome in those children with the chronic form has been transformed with the advent of liver transplantation. Native livers from five children who received allografts were studied pathologically and compared with earlier hepatic biopsies in two of these patients that had been performed several years before transplantation. Our findings support the conclusion that a sequence of morphologic changes from the initial micronodular cirrhosis through an intermediate mixed cirrhotic pattern to macronodular cirrhosis occurs. The micronodular phase is transitory, over a period of only a few months, since mixed micronodular macronodular cirrhosis was already present in the livers of children who received transplants by 11 months of age. Focal hepatocellular dysplasia was present in one of the livers with mixed cirrhosis but was not identified in the other two cases. Macronodular cirrhosis accompanied two cases of hepatocellular carcinoma in this study. In order to preclude the latter complication, liver replacement is necessary before the age of 2 years.

Preservation of canine hearts after warm ischemia (zero to thirty minutes) and one to two days of hypothermic storage. A comparative analysis of crystalloid and colloid solutions with different osmolarity and ion composition.

The effect of extracellular crystalloid (Ringer's) and colloid (silica gel fraction [SGF]) solutions, and intracellular crystalloid (Sacks) and colloid (modified silica gel fraction [MSGF]) solutions for canine heart preservation in a 24 to 48 hour model of hypothermic storage and zero to 30 minutes of warm ischemia was compared. Canine hearts flushed with an intracellular colloid solution (MSGF) had better survival rates after transplantation than did the hearts flushed with intracellular crystalloid solutions (Sacks). Better survival results also were observed in the group of hearts flushed with extracellular colloid (SGF) solutions than extracellular crystalloid (Ringer's) solutions. The most important theoretical factor in heart preservation appears to be hyperosmolarity and elevated concentration of potassium, proteins, and glucose.

Noninvasive outpatient nutritional therapy in inflammatory bowel disease.

Twelve courses of outpatient nutritional therapy using a specific defined formula, Precision High Nitrogen Diet, were given orally to nine malnourished patients with active inflammatory bowel disease. The regimen was continued for a 2-month period on an outpatient basis. Patients had significant increases in weight, height, and nutritional status as evaluated by serum protein and albumin levels and anthropometric measurements of triceps and subscapular skinfold thickness. Patients with no alteration of pharmacologic therapy did not differ significantly from those with increases in pharmacologic therapy in any parameter evaluated. This regimen is an alternative to total parenteral nutrition and nasogastric delivery of defined formula in malnourished patients with active inflammatory bowel disease.

Mechanistics of formation and ultrastructural evaluation of hepatocyte spheroids.

Freshly harvested rat hepatocytes form spheroids on uncoated positively charged polystyrene surfaces. Time lapse microscopy revealed that cell movement and reorganization were involved in spheroid formation. Ultrastructural evaluation using scanning and transmission electron microscopy indicated polarized cellular morphology and extensive cell-cell communication within spheroids. Bile canalicular structures were observed to surround each individual hepatocyte, forming an intricate three-dimensional continuous network of channels that appeared to end as pores/holes on the surface of the spheroid. The maintenance of differentiated cellular morphology coincided with preservation of hepatocyte viability and enhanced levels of tissue specific functions in spheroids.

Pediatric gastroenterology. Update on metabolic liver disease.

Wilson's disease, genetic and neonatal hemochromatosis, protoporphyria, tyrosinemia, and alpha1-antitrypsin deficiency are updated. Cost effectiveness of screening is discussed. Current therapies are evaluated, including the role of transplantation. The molecular biologic technique PCR is covered. Gene therapy is introduced.

A pediatric perspective on liver transplantation.

Liver transplantation has revolutionized the field of pediatric hepatology. The present status of this therapy is reviewed in this article from a nonsurgical perspective.

Decompressive craniectomy for the encephalopathy of Reye's syndrome.

Report of the successful use of a decompressive craniectomy for the encephalopathy of Reye's syndrome with increased intracranial pressure. The patient had failed to respond to all medical management.

Gastrointestinal complications following percutaneous kidney biopsy.

In most institutions, a percutaneous kidney biopsy is considered a safe procedure. However, multiple complications involving other organ systems have been reported. We present two cases in which complications following renal biopsy involved the gastrointestinal tract. The first case was manifested by pancreatitis and the formation of a pancreatic pseudocyst. The second case involved perforation of the small bowel. Neither patient required surgical intervention; both were managed conservatively and the outcome was excellent.

Hemangiomatosis of the colon and peritoneum: case report and management discussion.

A 3-month-old infant presented with ascites, anemia, minimal rectal bleeding, and thrombocytopenia. He was found to have several hundred small cavernous hemangiomas of the colon and peritoneal surfaces. Treatment consisted of laser surgery, subtotal colectomy, and steroids. A brief review of the literature on intestinal hemangiomatosis is included as well as the complications of the disease and current therapy.