The paediatric liver transplantation program at the Université catholique de Louvain.

The Paediatric Liver Transplant Program at Saint-Luc University Clinics constitutes a substantial single centre experience, including 667 transplantations performed between March 1984 and April 2003, and the history of this program reflects the tremendous progress in this field since twenty years. Liver transplantation in children constitutes a considerable undertaking and its results depend on multiple, intermingled risk factors. An analysis of the respective impact of several surgical and immunological parameters on patient/graft outcome and allograft rejection after paediatric liver transplantation showed a significant learning curve effect as well as the respective impact of pre-transplant diagnosis on survival and of primary immunosuppression on the rejection incidence. The introduction of living related liver transplantation in 1993 not only permitted to provide access to liver replacement in as many as 74% more candidate recipients, but also resulted in better graft survival and reduced retransplantation rate. The results of a recent pilot study suggest that steroid avoidance is not harmful, and could even be beneficial for paediatric liver recipients, particularly regarding growth, and that combining tacrolimus with basiliximab (anti-CD25 chimeric monoclonal antibody) for steroid substitution appears to constitute a safe alternative in this context. The long-term issues represent the main future challenges in the field, including the possibility of a full rehabilitation through immunosuppression withdrawal and tolerance induction, the development of adolescence transplant medicine, and the risk of early atherogenesis in the adulthood.

Posttransplant immune hepatitis in pediatric liver transplant recipients: incidence and maintenance therapy with azathioprine.

BACKGROUND: Cases of so-called autoimmune hepatitis (AH) have been reported after liver transplantation. Our aim was to evaluate the incidence in a series of 471 pediatric liver transplant recipients. METHODS: Between 1984 and 1998, 471 children had orthotopic liver transplantation (OLT). Children are followed up on a regular basis, with full clinical, biochemical, and histologic evaluation at 6 months, 1, 2, 5, 7, and 10 years after OLT. Children with unexplained abnormal liver tests were screened for autoimmune markers (total gamma-globulins, smooth muscle antibodies [SMA], liver kidney microsome antibodies [LKM], antinuclear factor [ANA]). From January of 1998 until December of 1998, autoimmune markers were prospectively searched in all children admitted for regular posttransplant follow-up (n = 118). RESULTS: Eleven of 471 children (2.35%) were found with autoimmune hepatitis, 9 retrospectively and 2 prospectively. None had previous autoimmune liver disease. Patients had a history of steroid-dependent hepatitis. Histology showed variable degree of portal and lobular inflammation, piecemeal necrosis, and bridging collapse. Mean (+/-SDS) aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities at diagnosis were 173+/-145 and 196+/-157 IU/L, respectively (nl<32). Median gamma-globulin levels reached 1365 mg/dl versus 931 mg/dl in controls (P<0.05). Nine had ANA (titer 1/80 up to 1/10,000), 1 SMA (1/320), and 2 LKM1 antibodies (1/1280). Patients did not respond to increasing charge of cyclosporine (n=10) or tacrolimus (n=1). Eleven received steroids (prednisolone: 2 mg/kg per day, then tapered) and azathioprine (1.5 to 2.5 mg/kg per day). All patients normalized within 3 months (mean AST/ALT levels of 26+/-8 and 30+/-9 IU/L). Three had mild to moderate relapse with increase of ALT thereafter. Gamma-globulins decreased to 1190 mg/dl (ns). Amongst the 116 remaining prospectively evaluated patients, 85 had normal evaluation, despite low titers of autoantibodies in 15 (SMA< or =1/40, ANA 1/80). Thirty-one patients had graft dysfunction, related to well-explained posttransplant causes, among which 7 had similar low levels of autoantibodies. CONCLUSIONS: A total of 2.35% of our transplant children present evidence of immune hepatitis after transplantation. Patients do not respond to increasing cyclosporine or tacrolimus levels and require steroid and azathioprine. In view of this specific treatment, systematic screening for "autoimmune" markers is advised in children with liver transplant.

Insulin signal transduction in rat small intestine: role of MAP kinases in expression of mucosal hydrolases.

The postreceptor events regulating the signal of insulin downstream in rat intestinal cells have not yet been analyzed. Our objectives were to identify the nature of receptor substrates and phosphorylated proteins involved in the signaling of insulin and to investigate the mechanism(s) by which insulin enhances intestinal hydrolases. In response to insulin, the following proteins were rapidly phosphorylated on tyrosine residues: 1) insulin receptor substrates-1 (IRS-1), -2, and -4; 2) phospholipase C-isoenzyme-gamma; 3) the Ras-GTPase-activating protein (GAP) associated with Rho GAP and p62(Src); 4) the insulin receptor beta-subunit; 5) the p85 subunits of phosphatidylinositol 3-kinase (PI 3-kinase); 6) the Src homology 2 alpha-collagen protein; 7) protein kinase B; 8) mitogen-activated protein (MAP) kinase-1 and -2; and 9) growth receptor-bound protein-2. Compared with controls, insulin enhanced the intestinal activity of MAP kinase-2 and protein kinase B by two- and fivefold, respectively, but did not enhance p70/S6 ribosomal kinase. Administration of an antireceptor antibody or MAP-kinase inhibitor PD-98059 but not a PI 3-kinase inhibitor (wortmannin) to sucklings inhibited the effects of insulin on mucosal mass and enzyme expression. We conclude that normal rat enterocytes express all of the receptor substrates and mediators involved in different insulin signaling pathways and that receptor binding initiates a signal enhancing brush-border membrane hydrolase, which appears to be regulated by the cascade of MAP kinases but not by PI 3-kinase.

Characteristics of Epstein-Barr virus primary infection in pediatric liver transplant recipients.

BACKGROUND/AIM: Pediatric liver transplant recipients are at high risk of Epstein-Barr virus infection. However the incidence of clinical symptoms and the graft function at the time of acute infection remains poorly documented. The aim of this study was to monitor the clinical and biochemical events associated with primary Epstein-Barr virus infection. METHODS: Clinical and biological patterns associated with Epstein-Barr virus infection were prospectively searched in 38 liver transplanted children. Polymerase chain reaction and anti-Epstein-Barr virus IgM antibodies were used at regular intervals to detect the timing of primary infection. RESULTS: Five children (13%) had pretransplant immunity, 26 (68.5%) developed primary Epstein-Barr virus infection 15 to 90 days after transplantation and seven (18.5%) remained Epstein-Barr virus negative. The four patients with clinical symptoms at the time of infection subsequently developed post-transplant lymphoproliferative disease. A single post-transplant lymphoproliferative disease occurred in non-symptomatic patients (overall incidence 13%). No mortality was associated with post-transplant lymphoproliferative disease. Two asymptomatic patients had abnormal liver function tests possibly related to primary Epstein-Barr virus infection. CONCLUSION: Epstein-Barr virus primary infection occurs in 80% of seronegative patients within 3 months after OLT. Clinical symptoms are rare and closely associated with post-transplant lymphoproliferative disease. Outside post-transplant lymphoproliferative disease, the consequences of infection are marginal.

Sclerosing cholangitis associated to cryptosporidiosis in liver-transplanted children.

UNLABELLED: Three children of a series of 461 pediatric liver transplant recipients developed diffuse cholangitis associated with intestinal cryptosporidium carriage. All three received immunosuppression consisting of tacrolimus and prednisone. Cryprosporidium carriage was treated with paramomycin, while immunosuppression was decreased according to graft tolerance. No other infectious pathogens were found, and no vascular problems were detected. Bile duct anastomosis was reoperated in all three, but biliary cirrhosis developed in one patient, requiring retransplantation. All three patients are alive and well, and free of intestinal parasites on follow-up. CONCLUSION: Cryptosporidium intestinal infection may play a role in some cases of otherwise unexplained cholangiopathies in pediatric liver transplant recipients. This may lead to significant morbidity, including need for retransplantation.

Saccharomyces boulardii upgrades cellular adaptation after proximal enterectomy in rats.

BACKGROUND: Saccharomyces boulardii is a non-pathogenic yeast which exerts trophic effects on human and rat small intestinal mucosa. AIMS: To examine the effects of S boulardii on ileal adaptation after proximal enterectomy in rats. METHODS: Wistar rats, aged eight weeks, underwent 60% proximal resection or transection and received by orogastric intubation either 1 mg/g body wt per day lyophilised S boulardii or the vehicle for seven days. The effects on ileal mucosal adaptation were assessed eight days after surgery. RESULTS: Compared with transection, resection resulted in mucosal hyperplasia with significant decreases in the specific and total activities of sucrase, lactase, and maltase. Treatment of resected animals with S boulardii had no effect on mucosal hyperplasia but did upgrade disaccharidase activities to the levels of the transected group. Enzyme stimulation by S boulardii was associated with significant increases in diamine oxidase activity and mucosal polyamine concentrations. Likewise, sodium dependent D-glucose uptake by brush border membrane vesicles, measured as a function of time and glucose concentration in the incubation medium, was significantly (p<0.05) increased by 81% and three times respectively in the resected group treated with S boulardii. In agreement with this, expression of the sodium/glucose cotransporter-1 in brush border membranes of resected rats treated with S boulardii was enhanced twofold compared with resected controls. CONCLUSION: Oral administration of S boulardii soon after proximal enterectomy improves functional adaptation of the remnant ileum.

Effects of alimentary intact proteins and their oligopeptide hydrolysate on growth, nitrogen retention, and small bowel adaptation in inflammatory turpentine rat.

The effects of dietary proteins given as whole proteins (WP) or as a peptide hydrolysate (PH) on growth, nitrogen retention, and small bowel adaptation were assessed using two groups of male Wistar rats. Measurements were made 18, 42, and 66 h after acute inflammation induced by subcutaneous injections of 0.125 mL turpentine and in two control groups (n = 12). The two diets had the same caloric, nitrogen, vitamin, and mineral content. The WP diet resulted in better weight gain, nitrogen retention, and small intestinal adaptation by control rats than did the PH diet. Loss of body weight after 18 h of acute inflammation was significantly lower and nitrogen retention significantly higher in animals on the WP diet than in those on the PH diet. Small intestine morphology was maintained with the WP diet, whereas villus height was significantly lower after 66 h, and there were fewer mitoses per crypt in the rats on the PH diet. Glucoamylase activity at all times, and N-aminopeptidase activity at 18 h, were significantly higher in rats on the WP diet. The putrescine (at 42 h) and spermidine (at 18 h) concentrations in the mucosa were higher in the rats on the WP diet. These data suggest that synthetic diets should be tested for their nutritional value during acute inflammation before they are used in human nutrition.

Acute parvovirus B19 infection associated with fulminant hepatitis of favourable prognosis in young children.

BACKGROUND: The cause of fulminant hepatitis (FH) in children is unexplained in up to 50% of cases. We report parvovirus B19 as an agent associated with FH in children and compare clinical characteristics of these patients with those of age-matched patients with FH of other origin. METHODS: 45 patients presented with FH. No cause was apparent in 21 patients. Parvovirus B19 genome was retrospectively sought by PCR in serum collected at admission in 41 patients. FINDINGS: Parvovirus B19 genome was detected in serum from four of 21 patients with unexplained FH (four of 11 younger than 5 years). No B19 DNA was detected in serum from patients with other types of FH or from 82 patients with biliary atresia. Parvovirus B19 IgM was detected in one of the four patients. Patients with parvovirus B19 infection had significantly lower bilirubin concentrations than age-matched patients with FH due to hepatitis A (nine) or other causes (nine) (poisoning with amanita excluded). All patients with parvovirus B19 survived without orthotopic liver transplantation, with restoration of normal liver function within 17 days. INTERPRETATION: In patients younger than 5 years with FH of unexplained origin, evidence of acute parvovirus B19 was associated with a distinct clinical pattern. In particular, low bilirubin concentrations and rapid recovery of liver function without transplantation were distinctive features.

Use of granulocyte macrophage colony stimulating factor in children after orthotopic liver transplantation.

BACKGROUND/AIMS: Bacterial infections complicate the course of up to 80% of pediatric liver transplant recipients, and in some cases, neutropenia, surgical complications and/or antibiotic resistance prevent successful control of sepsis. The aim of the present study was to evaluate the safety and efficacy of granulocyte macrophage colony stimulating factors (GM-CSF) in treating neutropenia following pediatric orthotopic liver transplantation. METHODS: Among a cohort of 430 pediatric orthotopic liver transplantation recipients, 13 children (12 months to 15 years, median 2 years, 10 males) received 15 courses of GM-CSF, 5 microg x kg(-1) x d(-1) subcutaneously, during their post-transplant course. In nine cases, the initial neutrophil count was below 1000/mm3. Ten patients were infected. Three received GM-CSF for severe sepsis without neutropenia. The mean duration of treatment was 16.3 days (range 4-49). RESULTS: In all but one neutropenic patient the neutrophil count increased above 1500/mm3 and the mean neutrophil count increased from 1392+/-1912/mm3 (range 130-7170, median 640) to 4508+/-2459/mm3 (range 350-9630, median 4390) (p<0.01). Only one neutropenic patient (FK506 related) failed to respond to treatment. No rejection episode was induced by treatment, no side effects were noted, and patients with sepsis were cured. CONCLUSION: In these patients, GM-CSF was safe, it achieved a significant increase in neutrophilic count, and was beneficial in patients with severe bacterial infections. This compound may prevent infectious complications in neutropenic patients and may benefit patients with severe sepsis with or without neutropenia.

Premature stimulation of rat sucrase-isomaltase (SI) by exogenous insulin and the analog B-Asp10 is regulated by a receptor-mediated signal triggering SI gene transcription.

The mechanism(s) by which insulin enhance prematurely the activity of brush border membrane (BBM) hydrolases in rat immature intestine is unknown. Therefore, we have compared the responses of four BBM enzymes [sucrase-isomaltase (SI), maltase, lactase-phloridzine hydrolase (LPH), and aminopeptidase] with exogenous insulin, the analog B-Asp10, IGF-I, and antireceptor MAb [insulin-receptor (IR) MAb] given to preweaning pups. Low doses of insulin caused a precocious induction of SI and of SI mRNA and stimulated maltase activity without effect on LPH nor on aminopeptidase activities. IGF-I given at the same dose as that of insulin had no detectable effect on these enzymes. Administration to sucklings of IR MAb prevented the effect of endogenous insulin by inhibiting the expression of SI and maltase without effect on LPH activity. B-Asp10, an insulin analogue that exhibits in vitro a 3.5-fold increase in receptor affinity with sustained signaling of the receptor tyrosine kinase, caused an overexpression of SI by 3.5-fold and of maltase by 1.5-fold compared with equivalent doses of normal insulin. The premature increases in SI activity, SI mRNA, and maltase activity in response to insulin were dose-dependent and were associated with dose-dependent increases in intracellular spermine and spermidine concentrations. In conclusion, these data suggest that the premature induction of SI by insulin is mediated by a dose-dependent signal initiated by binding of the hormone to its intestinal receptor, which after transduction into the cell indirectly triggers the transcription of the SI gene, possibly by changes in intracellular polyamine concentrations.

-Bioactive factors in milk-. / Les facteurs trophiques du lait.

Human milk as well as the milk of several mammalian species contains, beside major nutrients and anti-infectious and immunocompetent substances, a group of biologically active substances called "milk-borne trophic factors" or "growth modulators". Milk-borne trophic can be classified into three groups: hormones and trophic peptides; nucleotides, nucleosides and derived substances; and polyamines, especially spermine and spermidine. Certain hormones and peptides such as growth hormone, insulin, insulin like-growth factor I (IGF-I), epidermal growth factor (EGF), prolactin and growth hormone releasing factor (GHRF) can influence directly newborn's metabolism after intestinal absorption and promote growth and differentiation of several organs and target tissues. They could exert a cytoprotective effect against toxins and toxic substances and reduce the potential risk of necrotizing enterocolitis. Nucleotides are present in human milk at high levels, and are precursors of nucleic acids, which implies that they can enhance growth and differentiation of several organs and tissues, especially the liver. Nucleotides from milk enhance lipid metabolism, lipoprotein synthesis and liver cell function and regeneration. In addition, they have a determinant action on the development of the gut associated lymphoid tissue (GALT). Lastly, polyamines, mainly spermine and spermidine, are polycationic substances virtually present in all cells, whose concentration in human milk is about ten times higher than in infant formulae. In addition, spermine and spermidine levels increase markedly during the first 3 days of lactation reaching, after 1 week, plateau levels which are respectively 12 and eight times higher than the levels measured at day 0. Although several experimental studies have shown that polyamines from the milk of lactating mammals determine important mitogenic, metabolic and immunological effects promoting growth and differentiation of the immature gastrointestinal tract of the offspring, their beneficial effects on growth and differentiation of the gastrointestinal tract in humans remain hypothetical. As a consequence, enrichment of milk formulae in one or in several trophic factors is an important but complex goal. Its practical realization is not realistic today because of a too great number of incertitudes. The most important is related to potential beneficial or adverse effects emerging at short or at long term and to the individual interactions of these substances which could be agonist and antagonist because they are naturally present in milk as a "complex cocktail" whose composition changes during the lactation period.

Early signs and risk factors for the increased incidence of Epstein-Barr virus-related posttransplant lymphoproliferative diseases in pediatric liver transplant recipients treated with tacrolimus.

BACKGROUND: Posttransplant lymphoproliferative disease (PTLD) is a life-threatening condition the incidence of which in pediatric solid organ transplantation may be related to the immunosuppressive load. It has been suggested that tacrolimus, a new and potent immunosuppressor, causes an increased incidence of this syndrome. METHODS: The incidence, early signs, and risk factors for lymphoproliferative disease were reviewed in a cohort of 89 pediatric liver transplant recipients treated with tacrolimus. RESULTS: Eighteen patients (20%) developed a PTLD-16 concomitant to a primary Epstein-Barr virus (EBV) infection and 2 with previous immunity against EBV. Three additional patients had preliminary signs of PTLD concomitant to primary EBV infection, but did not develop individualized lymphoid masses. Six patients died (6.7% of all tacrolimus-treated patients). Mean tacrolimus blood level during the 3 months preceding EBV infection reached 11.8+/-1.8 ng/ml in PTLD patients versus 9.4+/-3.4 ng/ml in non-PTLD patients (0.05

Hirschsprung's disease: a 20-year experience.

During the period from 1972 to 1992, 59 children received surgical treatment at the University of Louvain Medical School for biopsy-proven Hirschsprung's disease (HD). The extent of aganglionosis was as follows: short segment restricted to the rectosigmoid or descending colon (n = 44, 75%); long segment (n = 9,15%); ultra-short segment (n = 3, 5%); unknown length because of death without autopsy (n = 3, 5%). The median age at operation was 7 months for short-segment disease compared with 14 months for those with long-segment disease. Surgical procedures used for short-segment disease were Swenson with colostomy (n = 16), Swenson-Pellerin without colostomy (n = 27), Duhamel (n = 1), and for long-segment disease were Martin (n = 3), Swenson-Deloyers (n = 2), Swenson-Boley (n = 2) and ileostomy only in = 2). Lynn's sphincteromyotomy was performed in the three ultra-short cases. There were six deaths (10%) at a median age of 86 days (range, 28 to 1545 days), three had long-segment disease, and the others were not classified because of death before curative surgery. Enterocolitis (EC) was the most common cause of death (five cases) and was also the major source of morbidity after curative surgery (12 of 44, 27%) in short-segment patients, three of seven (43%) in long-segment patients. The functional success of the procedure was evaluated in 70% of the surviving patients (37 of 53; mean follow-up, 8.7 years; range, 1.2 to 21.5), using a novel semiquantitative scoring system, specifically designed for children who have HD. This system assesses normal stool evacuation, abdominal distention, soiling, and severe incontinence. The results were compared with those from a population of 39 healthy children and adolescents and demonstrated progressive improvement in function during childhood and adolescence (P = .04) for patients treated for short-segment disease. However, function was found to be consistently poorer in all age groups when compared with healthy controls (5 to 10 years, P < .01; 10 to 15 years, P < .05; > 15 years, P < .01).

Expression of insulin receptors and of 60-kDa receptor substrate in rat mature and immature enterocytes.

The mechanism(s) by which rat immature enterocytes exhibit increased responsiveness to insulin before weaning is unknown. Therefore, we have analyzed the distribution, ontogeny, and molecular properties of insulin receptors (IR) and of related substrates in immature and mature enterocytes. IR were studied by radioligand binding assays, cross-linking labeling, immunohistochemistry, and in vitro phosphorylated substrates by immunoprecipitation. Regardless of age, 125I-insulin binding to IR was five times higher in crypt cells than in villus cells and two times higher in the ileum than in the jejunum. Binding capacity to villus cells from sucklings (day 14) exceeded three times that of older animals (day 30 and day 60). Scatchard analysis of equilibrium binding data confirmed an age-related decrease in low- and high-affinity receptor classes without change in affinity constants. In concordance, both alpha- and beta-IR subunits were more abundant in immature than in mature membranes. In vitro, insulin elicited the phosphorylation of three membrane proteins (96, 60 and 42 kDa), whose signals were virtually inhibited by preincubating membranes with antireceptor monoclonal antibodies. By immunoprecipitation, the 60-kDa signal was rapidly detected as a tyrosine-phosphorylated protein, expressed in mature and immature membranes, and identified as a receptor substrate phosphorylated in vitro by the IR tyrosine kinase. In conclusion, 1) increased responsiveness of rat immature enterocytes to insulin could be related to high membrane concentrations of IR and 2) normal rat enterocytes express a 60-kDa phosphotyrosine protein identified as a direct substrate of the IR tyrosine kinase.

Exogenous spermine induces maturation of the liver in suckling rats.

In the present study, we investigated the effects of spermine on postnatal liver maturation in suckling rats. The animals were given spermine either per os (8 micromol) or by intraperitoneal injection (1 micromol), once daily for three or five days. The percentage of liver cells in different cell cycle phases and of diploid cells in the parenchyma was estimated. The protein content, ornithine aminotransferase (OAT) activity, and content of DNA polyamines and receptors for polymeric immunoglobulins (RPI) were also measured in liver extracts. The ingestion of spermine had the following effects: the percentage of the cells in S and G2M phases of the cell cycle diminished the percentage of diploid cells increased the content of polymeric immunoglobulin receptors increased; the OAT activity increased; the contents of putrescine and spermidine decreased and almost reached adult values; and the spermidine/spermine ratio became similar to that observed in the liver of adult rats. These phenomena were detected 40 hours after the beginning of oral spermine treatment. The intraperitoneal injection of spermine had no effect on the OAT activity, but it decreased the spermidine content and enhanced the spermine content. Our data demonstrated for the first time that dietary polyamines play a role in the initiation of liver postnatal maturation in suckling rats.

Intestinal transport of calcium in rat biliary cirrhosis.

The characteristics of intestinal calcium transport in chronic cholestasis remain largely unknown. Using an experimental model of biliary cirrhosis in the rat, we aimed to investigate changes in calcium transport at the jejunal and ileal levels. Two methods were used: 1) uptake of 45Ca in brush border membrane vesicles and 2) measurements of transepithelial fluxes of calcium in Ussing chambers. Thirty days postsurgery, cholestatic rats presented biliary cirrhosis, with normal growth, normal daily energy, and calcium intakes, but had depressed circulating levels of 25-(OH)-vitamin D2 and 1,25-(OH)-vitamin D3. Compared with sham-operated controls, 45Ca uptake ([Ca2+] = 0.03 mmol) measured in vesicles from cholestatic rats was decreased by 3-fold in the duodenojejunum, in concordance with a lower content in brush border membrane calmodulin. Other changes in brush border membrane composition included decreases in structural proteins, microvillous enzymes, and in triglyceride content. Transepithelial fluxes of calcium measured in the ileum ([Ca2+] = 1.2 mmol) revealed in controls a net basal secretion flux (Jnet = -30.4 +/- 8.1 mmol.h-1.cm-2) that was reduced by 3-fold (p < 0.05) in vitamin D-deficient rats (Jnet = -10.4 +/- 4.8 mmol.h-1.cm-2). In response to 25-(OH)-vitamin D2 treatment, calcium uptake rates increased by 40% in the jejunum, whereas in the ileum, the secretion flux returned to basal control levels. Oral administration of taurocholate or tauroursodeoxycholate (50 mmol) depressed almost completely calcium uptake capacity in the duodenojejunum. By complexing free calcium, tauroconjugated bile acids inhibited in vitro calcium uptake proportionally to their concentration in the medium (0-40 mmol). Our data indicate that, in rat biliary cirrhosis, transport capacity of calcium in the duodenojejunum is markedly reduced in association with vitamin D deficiency and alterations in brush border membrane composition.

Branched chain amino acids improve body composition and nitrogen balance in a rat model of extra hepatic biliary atresia.

Malnutrition and growth retardation remain a major complication in infants with extrahepatic biliary atresia associated cholestasis. The purpose of this study was to investigate whether oral supplementation with branched chain amino acids (BCAA) can correct malnutrition in a rat model of biliary atresia. Four groups of 15 rats, 30 d old, were used. Group A were shamoperated animals, given a normal laboratory diet (17.5% of caloric intake as proteins). Group B were cholestatic rats (biliary atresia) fed a diet enriched in BCAA (supplement of 8.5%, valine/leucine/isoleucine ratio 1:1:1). Group C were cholestatic mice fed a diet enriched in casein (supplement of 8.5%). Group D were cholestatic mice fed a normal diet. Thirty-two days after surgery, groups were compared for body weight, serum amino acid content, nitrogen balance, muscle mass, and carcass composition. The results showed that the weight of group B, C, and D animals was 85, 81, and 64% of group A (controls). Serum BCAA levels were markedly increased in group B animals. Nitrogen retention was similar in groups B and A, but reduced to 63 and 44% in groups C and D, respectively. Dry weights were similar in group A (39.1% of body weight) and B (37.7%), but reduced to 28.1 and 28.6% of body weight in groups C and D. Body proteins were higher in groups A (13.9%) and B (14.2%) than in group D (9.7%) rats. Mineral content of group B animals was 84% of those of group A, 50% in group C, and 23% in group D rats. It was concluded that an oral supplement of BCAA can correct growth, nitrogen retention, and body composition in experimental biliary atresia. Administration of BCAA supplements to cholestatic infants should be considered.