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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.

Background: Gastroesophageal reflux is a common condition that in infants may lead to serious complication. This study assessed the efficacy and safety of oral cisapride suspension in the treatment of children 6 weeks to 2 years old with daily regurgitant reflux., Methods: A randomized, prospective, double-blind, placebo-controlled clinical trial was conducted at three study sites. After a 1 week baseline assessment, 45 infants 6 weeks to 2 years old were randomized to a double-blind trial in which they received a 6 week course of cisapride (0.2 mg/kg q6h) or a placebo suspension. Efficacy was assessed with 24 hour esophageal pH monitoring, esophageal manometry, and esophageal biopsy before and after the treatment period. A diary of regurgitation frequency and severity was kept by the parents. Safety was assessed by adverse event monitoring and standard laboratory measurements., Results: Compared with placebo, cisapride significantly (p < 0.05) reduced the mean duration of upright and supine reflux episodes. Compared to baseline, cisapride significantly reduced the mean duration of the longest reflux episode, and placebo increased the mean number of reflux episodes longer than 5 minutes. Cisapride was not significantly different from placebo for the following mean measurements: percent of total time pH < 4, number of reflux episodes, lower esophageal sphincter pressure, swallow pressure, regurgitation frequency or global evaluation scores., Conclusions: Cisapride is a safe, well tolerated prokinetic agent that improves the esophageal clearance of refluxed gastric acid in children under the age of 2 years.

Adaptation of the muscularis propria to intestinal resection is not well studied. Growing, 150- to 200-g Sprague-Dawley rats were divided into a resected group (R), which had 75% of the jejunoileum removed; a sham-resected group (SR); and a group of untreated controls (C). Food intake and weight gain were documented. Animals were killed on days 0, 10, 20, 30, or 40 (n = 14 animals for each day in each group). Small-intestinal length and jejunal circumference, wet weight/cm, thickness of the muscle layers, muscle morphometry, mg protein, and micrograms DNA per cm of the muscularis propria were measured. R rats had an initially greater food intake than SR or C animals, but the rate of weight gain was not different between groups. There was no significant increase in length of the residual intestine in R animals during the postoperative adaptive period, but circumference was significantly increased in R compared with SR or C animals. Wet weight/cm, mg protein, and micrograms DNA per cm of the muscularis propria were significantly greater in R compared with SR or C animals, but there was no change in thickness of the smooth-muscle layers in R versus SR or C rats. The number of cross-sectioned circular smooth-muscle cells/mm2 and the ratio of mg protein/micrograms DNA/cm length of muscularis propria were not different in R compared with SR or C animals. Intestinal resection resulted in a significant increase in circumference but not length of the residual intestine. A significant increase in the mass/cm, with no change in the number of cross-sectioned circular smooth-muscle cells/mm2 or in mg protein/micrograms DNA/cm of the muscularis propria, indicates that the adaptive response of muscularis propria is characterized by hyperplasia. This response potentially confers benefit to the organ and animal as a whole as a mechanism that permits structural and functional adaptation of the muscularis propria to resection.

This study prospectively evaluated 35 consecutive infants who presented with fresh blood mixed with stools. The mean age at onset of bleeding was approximately 4 weeks. All infants were otherwise asymptomatic and exhibited normal growth and physical examinations. None had evidence of a bleeding diathesis, viral or bacterial enteritis, or necrotizing enterocolitis. Consent for limited colonoscopy and biopsy was obtained for 34 infants. Twenty-five had macroscopic colitis and 10 infants had marked nodular lymphoid hyperplasia. Thirty-one infants had histopathological evidence of colitis characterized by a marked eosinophilic infiltrate. Compared with 19 controls (age, 4.1 +/- 3.6 months) the mean number of eosinophils per high-power field was greater in the patients with colitis. Patients with colitis also had an elevated mean absolute peripheral eosinophil count and a low mean serum albumin compared to control values. The 31 infants with colitis were receiving solely breast milk (10), cow's milk formula (9), soya formula (9), breast milk with cow's milk formula (2), or nutramigen (1) at the time of presentation. Nineteen infants had rapid resolution of frank bleeding and gradual correction of serum albumin with dietary change. While limited colonoscopy and biopsy were useful in establishing a definitive diagnosis, a low serum albumin and high peripheral eosinophil count suggested the diagnosis. Colitis characterized histologically by > 20 eosinophils per high-power field is a common cause of rectal bleeding in otherwise healthy young infants. Resolution of bleeding and increase in serum albumin after dietary change suggest that this is an allergic colitis: however, the pathogenesis of this disorder needs further clarification.

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.

A retrospective study of 76 children with hemolytic uremic syndrome (HUS) who were admitted to the Alberta Children's Hospital in Calgary. Alberta between January 1982 and December 1988 was undertaken to explore the gastrointestinal manifestations of the syndrome. The children (mean age of 4.0 +/- 3.1 years) presented primarily during the summer months with a microangiopathic hemolytic anemia (Hgb 94 +/- 26 g/L), thrombocytopenia (platelets 87 +/- 83 X 10(9)/L), and acute renal failure (oligoanuria with a BUN of 26 +/- 15 mmol/L, and a creatinine of 294 +/- 90 mumol/L). Forty-three children required dialysis for 10 +/- 17 days. The duration of hospitalization was 17 +/- 17 days. Four children died of complications attributable to HUS. The following symptoms and gastrointestinal manifestations of HUS were noted: fever (33%), vomiting (80%), abdominal discomfort/tenderness (59%), diarrhea (100%), hemorrhagic colitis (79%), rectal prolapse (13%), colonic stricture (3%), colonic perforation (1%), intussusception (1%), indirect hyperbilirubinemia (49%), and elevated hepatocellular enzymes (58%). Of the last 29 children studied, 19 (66%) had elevated levels of amylase and lipase in the presence of acute renal failure, and six (21%) had a marked elevation of lipase (more than four times normal) with additional supportive evidence of pancreatitis. The additional supportive evidence included persistent elevation of lipase after the resolution of acute renal failure in four children, a marked increment in lipase in association with abdominal pain and an abnormal ultrasound of the pancreas after the initiation of oral feeding in a fifth child, and pancreatic exocrine and endocrine necrosis at autopsy in a sixth child.(ABSTRACT TRUNCATED AT 250 WORDS)

A patient with celiac disease and the unusual features of transiently elevated sweat chlorides, reversible exocrine pancreatic insufficiency, symptomatic hypocalcemia/hypomagnesemia, and transient secondary hypoparathyroidism is presented along with a brief discussion of the physiologic mechanisms thought to underlie their development.