The impact of a gluten-free diet on adults with coeliac disease: results of a national survey.

UNLABELLED: OBJECTIVE We sought to evaluate the impact of the gluten-free diet on the 5,240 members of the Canadian Celiac Association (CCA). Data are presented on 2,681 adults (>or=16 years) with biopsy-proven celiac disease (CD). METHODS: A mail-out survey was used. Quality of life was evaluated using the 'SF12', and celiac-specific questions. RESULTS: Mean age was 56 years, mean age at diagnosis was 45 years, and 75% were female. The 'SF12' summary scores were similar to normative Canadian data, but were significantly lower for females and newly diagnosed patients. Respondents reported: following a gluten-free (GF) diet (90%), improvement on the diet (83%), and difficulties following the diet (44%), which included: determining if foods were GF (85%), finding GF foods in stores (83%), avoiding restaurants (79%), and avoiding travel (38%). Most common reactions to consumed gluten (among 73%) included pain, diarrhea, bloating, fatigue, nausea, and headache. Excellent information on CD and its treatment was provided by the CCA (64%), gastroenterologists (28%), dietitians (26%) and family doctor (12%). CONCLUSIONS: Quality of life in those with CD could be increased with early diagnosis, increased availability of gluten-free foods, improved food labelling, and better dietary instruction. Education of physicians and dietitians about CD and its treatment is essential.

GI complications in pediatric patients post-BMT.

This retrospective study comprehensively examined hepatic and gastrointestinal complications post-bone marrow transplant (BMT) in a heterogeneous group of 132 pediatric patients that underwent 142 transplants. Hyperbilirubinemia occurred in 28% of this population with clinically evident jaundice in 16%. Acute graft-versus-host disease (GVHD) occurred in 46% of the population, with liver involvement in 39% and intestinal involvement in 60% of those with acute GVHD. Veno-occlusive disease (VOD) occurred in 18% of the population. A greater increase in hepatic transaminases was noted in GVHD and VOD than nonspecific liver injury. Serum bilirubin may help to differentiate between VOD and hepatic GVHD. Biliary sludging occurred in 20% of patients and was associated with increased morbidity. Common post transplant gastrointestinal complications included mucositis in 90%, vomiting in 85% and abdominal pain in 71%. TPN support post transplant was required in 91%. Diarrhea occurred in 67% with the most common identified etiologies reported as GVHD (27%), viral (6%), Clostridium difficile (8%) infections and unknown (28%). Typhilitis developed in 3.5%. Melena or hematochezia occurred in 11 patients (8%). However, gastrointestinal bleeding was disproportionately represented in intensive care unit admissions (5/27) and 100 day mortality (5/21). Gastrointestinal and hepatic complications represent a major cause of morbidity and mortality in pediatric BMT recipients.

Incidence, survival and risk factors for the development of veno-occlusive disease in pediatric hematopoietic stem cell transplant recipients.

The incidence, risk factors and mortality of veno-occlusive disease (VOD) were identified for 142 pediatric hematopoietic stem cell (HSC) transplant recipients with hematological malignancies (83), solid tumors (41) and nonmalignant diseases (18). This historical cohort of 142 HSC transplant patients, from January 1993 through June 2000, was assessed by chart review. Risk factors for the development of VOD and mortality were assessed by multiple logistic regression and Kaplan-Meier survival curves respectively. The incidence of VOD was 18.3% (26/142 transplants). Multivariate analysis reconfirmed the known pretransplant risk factors of induction therapy with busulfan and transplantation with matched unrelated donor cells as significant risk factors for the development of VOD. In addition, two new risk factors, positive CMV serology in the recipient and TPN provided in the 30 days prior to transplant, were identified. Mortality in transplant patients at 100 days was greater in the VOD-positive group (10/26 (38.5%)) compared to the VOD-negative group (11/116 (9.5%) (P=0.001)). The risk of death was 4.97 times higher with 95% CIs (2.11, 11.71) for the VOD-positive group. Decreasing the risk factors for VOD may decrease mortality in this patient population.

Tissue transglutaminase enzyme-linked immunosorbent assay as a screening test for celiac disease in pediatric patients.

OBJECTIVE: An immunoglobulin A (IgA) anti-tissue transglutaminase antibody assay (anti-tTG) was compared with the conventional IgA anti-endomysium antibody assay (EMA) to assess its reliability as a screening test for celiac disease (CD) in a pediatric population. METHODS: Seventy-five IgA-sufficient and 2 IgA-deficient children who were scheduled for small intestinal biopsy for the evaluation of history or symptoms suggesting a diagnosis of CD were prospectively evaluated and enrolled in this study (gastrointestinal [GI] patients). In addition, 16 children with type I diabetes mellitus (DM) who had a positive EMA and a small bowel biopsy were included as a separate cohort. IgA anti-tTG was measured by enzyme-linked immunosorbent assay (ELISA), and IgA-EMA titers were determined by indirect immunofluorescence on cryopreserved sections of monkey esophagus. RESULTS: Nine of the 75 IgA-sufficient GI patients had a small bowel biopsy consistent with the diagnosis of CD. Eight of 9 IgA-sufficient patients with a positive small bowel biopsy had positive anti-tTG and EMA tests. Four IgA-sufficient patients had a false-positive anti-tTG ELISA and 2 had a false-positive IgA-EMA assay. In the IgA-sufficient patients, the sensitivity was 89% and the negative predictive value was 98% for either assay. The specificities of the IgA anti-tTG and the IgA-EMA tests were 94% and 97%, respectively (not significant). The positive predictive value of the IgA anti-tTG was 67%, compared with 80% for the IgA-EMA (not significant). In the 2 IgA-deficient children, one of whom had biopsy-proved CD, both tests were negative. In the 16 DM children 12 true- and 4 false-positive IgA anti-tTG and IgA-EMA results were identified. Three of 12 complained of GI symptoms. In follow-up, thus far, none of the DM patients with a false-positive anti-tTG have developed CD. CONCLUSIONS: The IgA anti-tTG antibody assay is equivalent to the IgA-EMA assay as a screening test for CD in IgA-sufficient pediatric patients. Intestinal biopsy remains the gold standard for the diagnosis of CD.

Intestinal permeability before and after ibuprofen in families of children with Crohn's disease.

BACKGROUND: Members of a subset of first-degree relatives of adults with Crohn's disease have been shown to have an increased baseline intestinal permeability and/or an exaggerated increase in intestinal permeability after the administration of acetylsalicylic acid. PURPOSE: To determine intestinal permeability in unaffected first-degree relatives of children with Crohn's disease before and after the administration of an ibuprofen challenge. METHODS: Lactulose-mannitol ratios, a measure of intestinal permeability, were determined in 14 healthy control families (41 subjects) and 14 families with a child with Crohn's disease (36 relatives, 14 probands) before and after ingestion of ibuprofen. An upper reference limit was defined using the control group as mean +/- 2 SD. RESULTS: The proportion of healthy, first-degree relatives with an exaggerated response to ibuprofen (20%, 95% CI 7% to 33%) was significantly higher than controls (P = 0.003). The exaggerated response was more common among siblings than among parents of pediatric probands. CONCLUSIONS: Members of a subset of first-degree relatives of children with Crohn's disease have an exaggerated increase in intestinal permeability after ibuprofen ingestion. These findings are compatible with there being a genetic link between abnormalities of intestinal permeability and Crohn's disease.

Use of immunoglobulin A-antiendomysial antibody to screen for celiac disease in North American children with type 1 diabetes.

OBJECTIVE: Our objective was to determine if a serological marker, the immunoglobulin A antiendomysial antibody (IgA-EMA), can be used to screen for celiac disease in North American children with type 1 diabetes. RESEARCH DESIGN AND METHODS: Subjects included 236 diabetes clinic patients and 56 gastrointestinal clinic patients who underwent intestinal biopsy for suspected malabsorption. Total IgA and IgA-EMA assays were performed. Diabetic patients who were positive for IgA-EMA were asked to undergo biopsy. RESULTS: Of 236 diabetic patients tested, none were IgA deficient and 19 were positive for IgA-EMA (8%). Of 17 patients biopsied, 12 had celiac disease and 3 were symptomatic. The estimated prevalence of celiac disease was 5.1%, consistent with data from European diabetic clinics. Of the 56 gastrointestinal clinic patients, the 3 who were IgA-EMA positive had biopsies diagnostic of celiac disease. Three were found to be IgA deficient, one of whom had celiac disease. Of the 50 IgA-sufficient and IgA-EMA-negative patients, 1 had celiac disease and 49 did not. The IgA-EMA test had a sensitivity of 94% and a specificity of 91% for IgA-sufficient biopsied patients. CONCLUSIONS: IgA-EMA is an appropriate tool for demonstrating an increased prevalence of celiac disease in a North American pediatric diabetic population. Positive testing should be confirmed by intestinal biopsy, and false-positive results require serial follow-up. Symptomatic children require biopsy regardless of their IgA-EMA status.

Plasma L-arginine concentration, oxygenation index, and systemic blood pressure in premature infants.

OBJECTIVE: To determine the relationships between plasma L-arginine concentrations and the severity of respiratory distress syndrome (RDS) or systemic blood pressure in premature infants. DESIGN: Prospective, observational study. SETTING: Neonatal intensive care, tertiary referral hospital. SUBJECTS: Fifty-three premature infants. INTERVENTIONS: We measured arginine and nutritional intake, plasma arginine concentration, total amino acid concentrations, and blood pressure on days 3, 7, 14, and 21 of life. In 33 infants who received assisted ventilation, oxygenation index could be calculated to reflect the severity of RDS. The relationships between plasma arginine and oxygenation index or blood pressure were analyzed using multiple linear regression. MEASUREMENTS AND MAIN RESULTS: On day 3, plasma arginine concentrations were decreased compared with normal published values. Arginine concentrations increased with the day of life of measurement (p < .001) and with arginine intake (p < .001). After adjusting for arginine intake and day of life, an inverse relationship was found between oxygenation index and plasma arginine concentrations: (p = .025). No similar relationship was found between oxygenation index and the concentration of total amino acids. A weak positive relationship was found between plasma arginine concentration and systemic blood pressure. CONCLUSIONS: Increments in the oxygenation index, reflective of an increased severity of RDS, are associated with a decrease in plasma arginine concentration. This finding may reflect arginine consumption by the nitric oxide synthase pathway in the lungs of premature infants with RDS, or may be explained by increased arginine catabolism. The lack of a similar relationship between total plasma amino acids and oxygenation index supports the first interpretation.

Plasma L-arginine concentrations in premature infants with necrotizing enterocolitis.

OBJECTIVE: To determine whether L-arginine concentrations (the substrate for nitric oxide synthesis) are lower in premature infants in whom necrotizing enterocolitis (NEC) develops than in unaffected infants. METHODS: We measured arginine and nutritional intake, plasma arginine, glutamine, total amino acids, and ammonia concentrations in 53 premature infants (mean gestational age +/- SD: 27 +/- 1.7 weeks) at risk of NEC. Measurements were done on days 3, 7, 14 and 21 and just before treatment in infants with NEC. RESULTS: Necrotizing enterocolitis developed in 11 infants between postnatal days 1 and 26. On day 3, plasma arginine concentrations were decreased compared with normal published values (mean +/- SE, 41 mumol/L +/- 4). Arginine concentrations increased with day of life of measurement (p < 0.001) and arginine intake (p < 0.001). Plasma arginine concentrations were significantly lower at the time of diagnosis in infants with NEC compared with control subjects, even after adjusting for arginine intake and day of life (p = 0.032). Plasma glutamine and total amino acid concentrations were not significantly different in infants with NEC compared with control subjects. Plasma ammonia concentrations were elevated on day 3 (mean +/- SE, 72 +/- 3.3 mumol/L) and decreased with postnatal age (p < 0.001) and increasing plasma arginine concentrations (p < 0.001). CONCLUSION: Plasma arginine concentrations are decreased at the time of diagnosis in premature infants with NEC. The potential benefit of arginine supplementation in the prevention of the disease deserves evaluation.

Oral rehydration solution in the year 2000: pathophysiology, efficacy and effectiveness.

The use of oral rehydration solution (ORS) with early refeeding forms the basis of therapy for dehydration secondary to diarrhoea ORS has produced such positive results in dehydrated patients that no further scientific demonstration is needed to confirm its efficacy. This review presents several issues that remain unsettled or controversial. They include the following. 1. The mechanism of water handling by the intestine is discussed; this is more complex than initially thought, at the epithelial, cellular and molecular level. 2. The composition of ORS which has been successfully adapted for the most frequent conditions, except for severely malnourished children, is described. 3. In contrast to the strong scientific basis and obvious efficacy in rehydration of ORS, its consequences for growth, nutrition and mortality are difficult to demonstrate, unless adequate long-term nutritional support is also provided in addition to ORS. 4. Finally, discrepancies between the recommendations and the practice of oral rehydration therapy are now well documented. Analysis of the causes of these discrepancies may participate in improving public health campaigns.

Elevated aminotransferase activity as an indication of muscular dystrophy: case reports and review of the literature.

Five male children are reported in whom incidental recognition of elevated serum alanine aminotransferase (ALT) activity initiated investigation to identity the cause of suspected hepatocellular injury. All five were later diagnosed with X chromosome-linked muscular dystrophy. The serum level of ALT, generally considered to be specific for hepatocellular injury, was increased two to 25 times above normal in all the reported cases. Paradoxically, the increase in ALT activity was greater than that of serum aspartate aminotransferase (three to 16 times normal), an enzyme whose elevation is generally recognized as being less specific and indicative of muscle, cardiac, kidney, pancreatic, red blood cell or hepatic injury. At presentation to the gastrointestinal service, one case, age 2.5 months, had no symptoms or signs of neuromuscular dysfunction, while the other four had previously unrecognized hypertrophy of the calves, proximal limb weakness, positive Gower's sign or delayed gross motor skills. All five patients had marked elevation of serum creatine kinase activity and histopathologically confirmed muscular dystrophy. The practical clinical implication of this report is that children with elevated serum ALT, in the absence of other signs and symptoms of hepatic injury, may have occult muscular disease--most frequently muscular dystrophy. Although the clinical signs of muscular dystrophy may be subtle or absent, early determination of creatine kinase will suggest the correct diagnosis and minimize extensive and invasive investigation focusing on hepatic injury.

Butyrate enema therapy stimulates mucosal repair in experimental colitis in the rat.

BACKGROUND: The short chain fatty acid (SCFA) butyrate provides energy for colonocytes, stimulates colonic fluid and electrolyte absorption and is recognised as an effective treatment for multiple types of colitis. AIM: To examine the impact of butyrate enema therapy on the clinical course, severity of inflammation, and SCFA stimulated Na+ absorption in a chronic experimental colitis. METHODS: Distal colitis was induced in rats with a trinitrobenzenesulphonic acid (TNBS) enema. Five days after induction, rats were divided into groups to receive: no treatment, saline enemas, or 100 mM Na-butyrate enemas daily. On day 24, colonic damage score and tissue myeloperoxidase (MPO) activity were evaluated. Colon was mounted in Ussing chambers and Na+ transport and electrical activities were measured during a basal period and after stimulation with 25 mM butyrate. RESULTS: In the untreated and the saline enema treated TNBS groups, diarrhoea and extensive colonic damage were seen, associated with increased tissue MPO activities and absent butyrate stimulated Na+ absorption. In contrast, in the butyrate enema treated TNBS group, diarrhoea ceased, colonic damage score improved, and tissue MPO activity as well as butyrate stimulated Na+ absorption recovered to control values. CONCLUSION: Butyrate enema therapy stimulated colonic repair, as evidenced by clinical recovery, decreased inflammation, and restoration of SCFA stimulated electrolyte absorption.

Inhibition of short-chain fatty acid absorption and Na+ absorption during acute colitis in the rabbit.

BACKGROUND/AIMS: Short-chain fatty acids (SCFAs) provide energy for colonocytes and stimulate colonic fluid and electrolyte absorption. The impact of acute colitis on SCFA-stimulated Na+ absorption and SCFA absorption was examined. METHODS: Proximal colon from rabbits infected with Yersinia entercolitica, a pair-fed group, and controls was mounted in Ussing chambers, and Na+ transport, short-circuit current, and tissue conductance were examined during a basal period and after stimulation with the SCFAs, butyrate, or propionate. Propionate transport and luminal SCFA concentration were evaluated. RESULTS: Butyrate and propionate stimulated electroneutral Na+ absorption above basal levels in the control and pair-fed groups, as evidenced by significant increases in mucosal-to-serosal and net Na+ fluxes with no change in serosal-to-mucosal flux, short-circuit current, or conductance. Butyrate-stimulated Na+ absorption and propionate absorption were blocked by amiloride, an inhibitor of Na(+)-H+ exchange. In the infected group, both butyrate and propionate failed to stimulate colonic Na+ absorption above basal levels. Propionate absorption was inhibited, and epinephrine failed to stimulate Na+ or propionate absorption. Luminal SCFA concentrations were increased in acute colitis. CONCLUSIONS: Inhibition of SCFA-stimulated Na(+)-H+ exchange and SCFA absorption contribute to the diarrheal fluid loses observed in acute colitis and may reduce colonocyte energy supply.

Luminal factors stimulate intestinal repair during the refeeding of malnourished infant rabbits.

We examined the role of luminal versus systemic factors in promoting intestinal recovery during the refeeding of previously malnourished infant rabbits. Malnutrition was induced by litter expansion at 7 days of age. A 20-cm Thirty-Vella (T-V) loop was created in the intestine of each malnourished and dietary control animal at 21 days of age. Beginning on day 28, controls and one half of the malnourished group (malnourished-refed) were fed chow ad libitum, whereas the remainder of the malnourished group received half the amount of chow given to the malnourished-refed group. On day 35, proximal and distal segments from the intact intestine that remained in continuity as well as segments from the excluded T-V loops were examined. Malnutrition severely reduced mucosal mass and disaccharidase activities in the intact distal intestine. A brief period of refeeding led to a rapid recovery of these parameters. In contrast, the excluded T-V loop segments of the control, malnourished, and malnourished-refed groups all displayed decreased mucosal mass and impaired function to a degree similar to that observed in the intact distal segment from the malnourished group. These results indicate that luminal factors are essential for (i) the maintenance of normal intestinal structure and function in infant rabbits and (ii) the promotion of mucosal repair following nutritional rehabilitation of malnourished animals.

Acute pancreatitis in a child with sickle cell anemia.

A case of pancreatitis that occurred as a complication of a vaso-occlusive crisis in a child with sickle cell anemia is reported. We encourage others to consider pancreatitis as a cause for abdominal pain in children with multisystem diseases, particularly those that may cause ischemic organ injury such as sickle cell anemia.

Regulation of intestinal glucose transport.

The small intestine is capable of adapting nutrient transport in response to numerous stimuli. This review examines several possible mechanisms involved in intestinal adaptation. In some cases, the enhancement of transport is nonspecific, that is, the absorption of many nutrients is affected. Usually, increased transport capacity in these instances can be attributed to an increase in intestinal surface area. Alternatively, some conditions induce specific regulation at the level of the enterocyte that affects the transport of a particular nutrient. Since the absorption of glucose from the intestine is so well characterized, it serves as a useful model for this type of intestinal adaptation. Four potential sites for the specific regulation of glucose transport have been described, and each is implicated in different situations. First, mechanisms at the brush-border membrane of the enterocyte are believed to be involved in the upregulation of glucose transport that occurs in streptozotocin-induced diabetes mellitus and alterations in dietary carbohydrate levels. Also, factors that increase the sodium gradient across the enterocyte may increase the rate of glucose transport. It has been suggested that an increase in activity of the basolaterally located Na(+)-K+ ATPase could be responsible for this phenomena. The rapid increase in glucose uptake seen in hyperglycemia seems to be mediated by an increase in both the number and activity of glucose carriers located at the basolateral membrane. More recently, it was demonstrated that mechanisms at the basolateral membrane also play a role in the chronic increase in glucose transport observed when dietary carbohydrate levels are increased. Finally, alterations in tight-junction permeability enhance glucose absorption from the small intestine.(ABSTRACT TRUNCATED AT 250 WORDS)

Refeeding enhances intestinal repair during an acute enteritis in infant rabbits subjected to protein-energy malnutrition.

We examined the effects of refeeding during an acute bacterial enteritis on small intestinal repair in infant rabbits subjected to protein-energy malnutrition and in noninfected and infected dietary controls. Malnutrition was induced by litter expansion at 7 d of age. Randomly selected litters from both dietary groups were infected on d 17 with Yersinia enterocolotica. Inflammation and intestinal damage were observed in the jejunum and ileum at the "acute stage" of infection in 23-d-old animals from both dietary groups, as evidenced by an inflammatory infiltrate, blunted villi, and reduced disaccharidase activities. In addition, ileal glucose-stimulated Na+ absorption was depressed. On d 24, a 7-d period of ad libitum refeeding of breast milk and rabbit feed was initiated in randomly selected litters of infected-malnourished animals and all dietary controls. Mucosal repair was nearly complete at 31 d of age in infected dietary controls and in the infected-malnourished animals that were refed, as demonstrated by the recovery of segmental mucosal mass and ileal glucose-stimulated Na+ transport in association with the resolution of inflammation and diarrhea. Only mucosal disaccharidase activities remain depressed. In contrast, in 31-d-old infected-malnourished animals subjected to ongoing nutrient deprivation, severe intestinal damage persisted as evidenced by increased mortality, ongoing intestinal inflammation, mucosal hypoplasia, depressed disaccharidase activities, and reduced glucose-stimulated Na+ transport. We conclude that a refeeding regimen introduced during an acute bacterial enteritis is well tolerated and promotes recovery of intestinal mass, structure, and function in malnourished infant rabbits and dietary controls.

The role of gastroesophageal reflux in pediatric dysphagia.

The history, physical examination, and the results of the upper gastrointestinal series, esophageal manometry, 24-h pH recording, endoscopy, and biopsy are reviewed in 16 children (mean age of 10.6 years, range of 3 years 5 months to 15 years 3 months) who presented to the Alberta Children's Hospital with dysphagia ("food-sticking") without previously identified provocative disorders since January 1985. Of the 16 patients, 11 had had intermittent obstruction, and 7 had had intervention to relieve obstruction (2 Heimlich maneuvers, 1 intravenous glucagon, and 4 endoscopy after failure of intravenous glucagon). Although only five children had a recent history suggestive of gastroesophageal reflux, 12 had histologic evidence of reflux esophagitis (including 1 with a peptic stricture, 1 with "nutcracker" esophagus, and 1 with esophageal dysmotility characteristic of Down's syndrome) and all responded clinically to antireflux therapy. Of the remaining four patients, one had extrinsic esophageal compression from a vascular ring (right aortic arch with left ligamentum arteriosum), one had a single and another had recurrent episodes of food-sticking without any identified abnormality, and one declined investigation. In childhood, dysphagia may be the presenting symptom of reflux esophagitis in the absence of a history suggestive of gastroesophageal reflux and without evidence of a peptic stricture.

Effects of malnutrition on microvillus membrane glucose transport and physical properties.

We examined sodium-dependent glucose transport, membrane lipid composition, and membrane fluidity in microvillus membrane vesicles isolated from the distal intestine of infant rabbits subjected to protein-energy malnutrition and age-matched controls. In vesicles from malnourished animals, sodium-dependent glucose transport was significantly enhanced, as evidenced by a twofold increase in maximal transport capacity, Jmax. Carrier affinity for glucose, as assessed by the Km of the transport process, was unaffected. These alternations were associated with marked changes in microvillus membrane composition. Malnourished animals had an increase in the lipid-to-protein ratio of the microvillus membrane, which suggests that malnutrition might be associated with either a reduction in membrane protein or an increase in membrane lipid. This would be expected to increase the fluidity of the microvillus membrane. However, we observed no differences in either the static or dynamic component of membrane fluidity, using multiple fluorescent probes, between dietary groups. Further analysis of membrane lipids was undertaken to establish whether quantitative differences in lipid subclasses could explain this discrepancy. We found that nutrient deprivation produced numerous alterations in membrane lipids. The major findings were an increase in both the cholesterol-to-phospholipid and phosphatidylethanolamine-to-phosphatidylcholine ratios. Both alterations would be expected to decrease membrane fluidity and presumably represent a compensatory response to the loss of membrane protein. Thus chronic postnatal protein-energy malnutrition initiates several adaptive responses that include major alterations in the chemical composition of the microvillus membrane. The resulting effect preserves efficient glucose transport and maintains the physical properties of the microvillus membrane.

Impact of refeeding on intestinal development and function in infant rabbits subjected to protein-energy malnutrition.

The impact of early postnatal protein-energy malnutrition and of 4, 7, and 14 d of nutritional rehabilitation on small intestinal growth, development, structure and function was examined in 28-, 32-, 35-, and 42-d-old infant rabbits. Malnutrition was induced by litter expansion 7 d postpartum and, in randomly selected malnourished animals, refeeding was begun at weaning, 28 d. Results are compared to ad libitum fed dietary controls. Malnutrition altered the small intestine of the developing rabbit, as evidenced by: 1) reduced jejunal and ileal mass as shown by decreased mucosal wt, protein, and DNA content; 2) depressed epithelial proliferation and enterocyte migration along the crypt-villus axis; 3) delayed epithelial maturation as measured by mucosal enzyme activities; and 4) enhanced glucose-stimulated Na+ transport. Refeeding stimulated rapid and complete recovery, as evidenced by: 1) restoration of jejunal and ileal mucosal mass within 4 d; 2) enhancement of epithelial renewal and enterocyte migration by 7 d; and 3) complete return of the normal pattern of mucosal enzymes by 14 d. With 7 d of refeeding, glucose-stimulated Na+ transport was down-regulated to the level of dietary controls. We conclude that early postnatal protein-energy malnutrition has a severe impact on small intestinal growth, development, structure, and function. Furthermore, a brief period refeeding induced a rapid and complete recovery of these parameters.