Sterol profiling in red blood cell membranes and plasma of newborns receiving total parenteral nutrition.

BACKGROUND AND OBJECTIVES: Total parenteral nutrition (TPN) is a lifesaving therapy in children with intestinal failure, frequently complicated by liver dysfunction. Plant sterols (phytosterols) of lipid emulsions have been supposed to contribute to cholestasis in TPN-treated children. The present study aimed to evaluate the plasma and red blood cell membrane (RBCM) phytosterol levels in newborns after a short period of TPN. PATIENTS AND METHODS: Phytosterols, cholesterol, and other sterol levels were quantified by gas chromatography-mass spectrometry in 15 healthy control infants, 22 patients after TPN, and 11 patients before TPN. Sterols of lipid emulsions were quantified. RESULTS: Plasma and RBCM phytosterol levels were, respectively, on average 56 micromol/L and 83 micromol/g per protein in patients after TPN, 13 micromol/L and 15 micromol/g per protein in patients before TPN, and 9 micromol/L and 13 micromoL/g per protein in control infants (P < 0.05 for differences). The days of TPN and the total amount of infused lipids correlated significantly with RBCM phytosterol (P < 0.05); correlations for plasma were positive but not significant. No correlation was observed with plasma bilirubin, gamma-glutamyltransferase, or alanine transaminase. CONCLUSIONS: Plasma and RBCM phytosterols increase significantly in newborns after a short period of TPN. Higher phytosterol levels were observed in some patients that could have been due to their individual variability in phytosterol metabolism and/or clearance. A greater accumulation of phytosterols in membranes may induce TPN-related cholestasis.

Effect of intragastric volume and osmolality on mechanisms of gastroesophageal reflux in children with gastroesophageal reflux disease.

OBJECTIVE: Both transient lower esophageal sphincter (LES) relaxations (TLESRs) and periods of low/absent LES pressure (LESP) are the main mechanisms of gastroesophageal reflux. These events are believed to be triggered by stimuli from different areas of the upper GI tract. We aimed at investigating the relationship between LESP profile and gastric emptying and distension after meals of different composition in 30 children with gastroesophageal reflux disease (median age 7.0 yr, range 12 months-12 yr). METHODS: Recordings of LESP and intraesophageal pH for 1 h fasting and for 2 postprandial h were performed with a perfused sleeve catheter and flexible electrode, respectively; gastric emptying and distension of antral area were simultaneously recorded with real-time ultrasonography. Ten patients had a standard meal (group A), 10 had a high-volume meal (group B), and 10 had a high-volume and osmolality meal (group C). RESULTS: Postprandial esophageal acid exposure was significantly higher in patients of groups B and C than in patients of group A (p < 0.01); it was also more prolonged in patients of group C than in subjects of group B (p < 0.05). A higher postfeeding rate of reflux episodes caused by TLESRs was detected in patients of groups B and C as compared with patients of group A (p < 0.01). This increase did not statistically differ in patients of groups B and C. Patients of group C exhibited a higher postprandial rate of reflux episodes associated with low/absent tone of the LES as well as a more prolonged gastric emptying time and a higher postfeeding gastric distension as compared with patients of groups A and B (p < 0.01). Finally, a significant correlation was only found between the postprandial rate of reflux events resulting from low/absent LESP and the degree of antral distension in patients of group C (p < 0.01). CONCLUSION: Gastroesophageal reflux is worsened by increasing the volume and osmolality of meals through significant changes of LESP. Meals of high volume and meals with high volume and osmolality cause a comparable increase of reflux episodes as a result of TLESRs. However, meals with high volume and osmolality cause the higher degrees of esophageal acid exposure than meals with high volume resulting from a higher rate of reflux episodes associated with low/absent LESP. This finding correlates with a high postfeeding antral distension.

A case of protein-losing enteropathy caused by intestinal lymphangiectasia in a preterm infant.

Intestinal lymphangiectasia is characterized by obstruction of lymph drainage from the small intestine and lacteal dilation that distorts the villus architecture. Lymphatic vessel obstruction and elevated intestinal lymphatic pressure in turn cause lymphatic leakage into the intestinal lumen, thus resulting in malabsorption and protein-losing enteropathy. Intestinal lymphangiectasia can be congenital or secondary to a disease that blocks intestinal lymph drainage. We describe the first case of intestinal lymphangiectasia in a premature infant. The infant presented with peripheral edema and low serum albumin; high fecal concentration of alpha(1)-antitrypsin documented intestinal protein loss. Endoscopy showed white opaque spots on the duodenal mucosa, which indicates dilated lacteal vessels. Histology confirmed dilated lacteals and also showed villus blunting. A formula containing a high concentration of medium chain triglycerides resulted in a rapid clinical improvement and normalization of biochemical variables. These features should alert neonatologists to the possibility of intestinal lymphangiectasia in newborns with hypoalbuminemia and peripheral edema. The intestinal tract should be examined for enteric protein losses if other causes (ie, malnutrition and protein loss from other sites) are excluded. The diagnosis rests on jejunal biopsy demonstrating dilated lymphatic lacteal vessels.

Comparison of gastric electrical activity and gastric emptying in healthy and dyspeptic children.

To assess and compare gastric electrical activity and gastric emptying recorded from dyspeptic and healthy children, cutaneous electrogastrography and ultrasound examination of the gastric emptying were simultaneously performed in 52 children with nonulcer dyspepsia and 114 healthy children. Symptoms were scored from 0 (none) to 6 (severe). A higher percentage of tachygastria, a higher instability of gastric power, and a lower post/preprandial ratio were present in dyspeptic children than healthy children. As regards the ultrasound parameters, the fasting antral area and T1/2 were similar in dyspeptic children and controls. Only 32% of dyspeptic children had a normal gastric emptying time vs 66% of healthy children. Marked postprandial antral dilatation was found in the dyspeptic children, which correlated with the total symptom score. Electrogastrographic and gastric emptying parameters show specific differences in dyspeptic children with respect to controls, both fasting and after a meal. The postprandial antral distension correlates with the severity of the symptoms.

A normal gastrointestinal motility excludes chronic intestinal pseudoobstruction in children.

Gastrointestinal manometry has gained wide acceptance in the approach to patients with suspected enteric neuromuscular disorders. However, performing gastrointestinal manometry in these subjects without a previous exhaustive diagnostic evaluation is unjustified. Twelve children (median age: 7.0 years; range: 8 months-13 years), with clinical and x-ray features suggesting chronic intestinal pseudoobstruction, were referred to our unit for gastrointestinal manometry. The latter was performed with a perfused catheter for 5 hr in the fasting state and for 90 min after feeding. Data were compared with those recorded in eight age-matched controls. In all patients and controls, interdigestive motor complexes with propagated phases III were detected; a regular postprandial antroduodenal motor activity was also recorded. Patients and controls did not differ for fed antral and duodenal motility indexes, fed antroduodenal coordination, and length of duodenal phase III. Most of the patients showed short or prolonged bursts of nonpropagated activity in the fasting and/or fed states; in four cases fasting and/or fed sustained phasic activity was recorded. Manometric evidence of migrating motor complexes and postfeeding activity did not support the diagnosis of intestinal pseudoobstruction and suggested redirecting the diagnostic evaluation. Final diagnoses were: Munchausen syndrome-by-proxy (four cases), celiac disease (two cases), intestinal malrotation (two cases), Crohn's disease (two cases), multiple food intolerance (one case), and congenital chloride-losing diarrhea (one case). It is concluded that in children with suspected chronic intestinal pseudoobstruction manometric evidence of migrating motor complexes and fed motor activity excludes an enteric neuromuscular disorder and suggests a reassessment of the diagnostic work-up. Furthermore, if gastrointestinal manometry shows migrating motor complexes and postfeeding motor activity, qualitative abnormalities of the manometric tracings do not indicate an underlying enteric neuromuscular disorder and must not be overemphasized. Patients referred for gastrointestinal manometry should previously undergo an extensive diagnostic investigation to exclude disorders mimicking chronic intestinal pseudoobstruction.

Lansoprazole in the treatment of gastro-oesophageal reflux disease in childhood.

BACKGROUND: Acid suppressive therapy is the mainstay of pharmacologic treatment of gastro-oesophageal reflux disease. Use of proton pump inhibitors in children is still limited and has only included omeprazole in a few controlled studies. AIM: To determine efficacy of lansoprazole, a relatively new proton pump inhibitor, on symptoms and oesophagitis in a group of children with gastro-oesophageal reflux disease refractory to H2 receptor antagonists. The required dose of the drug for inhibiting gastric acidity was also determined. PATIENTS AND METHODS: A series of 35 children (median age: 7.6 years, range: 3-15) with oesophagitis refractory to H2 receptor antagonists received a 12-week therapeutic course with lansoprazole. Prior to the study children underwent symptomatic and endoscopic assessment, oesophageal manometry and 24-hour intragastric and intra-oesophageal pH test. The latter was repeated after one week of therapy while patients were on treatment in order to monitor the degree of acid suppression and adjust the dose of the drug. Symptomatic assessment and endoscopy were repeated at the end of the trial RESULTS AND CONCLUSIONS: In 12 patients (group A), the initial dose of the drug was efficacious (1.3 to 1.5 mg/kg/day), whereas in 23 [group B) the initial dose (0.8 to 1.0 mg/kg/day) was increased by half because of insufficient inhibition of intragastric acidity (i.e., when the intra-gastric pH remained below 4.0 for more than 50% of the recording time). Nine patients in group A (75%) and 8 in group B (53.5%) healed (chi2: 3.6, p<0.05); 1 patient in group A [8.3%) and 7 in group B (30.5%) remained unchanged (chi2: 6.9, p<0.01); 2 patients in group A and 8 in group B improved and underwent a further month of therapy. The two groups did not differ as far as concerns baseline pH, endoscopic and clinical variables. In both groups, those patients failing to respond at the end of the trial showed a more impaired oesophageal motility than improved or healed patients. The drug was well tolerated and no significant laboratory abnormalities occurred. In children with gastro-oesophageal reflux disease refractory to H2 receptor antagonists, a 12-week course of lansoprazole is effective both in healing oesophagitis and improving symptoms. An initial dose of 1.5 mg/kg/day of the drug is suggested. However, if during treatment, patients remain symptomatic the dose should be increased and a prolonged intra-gastric and intra-oesophageal pH test performed to evaluate the acid suppression efficacy of the adjusted dose. A short course of lansoprazole appears to be safe and well tolerated in paediatric age.

Gestational maturation of electrical activity of the stomach.

Gestational maturation of gastrointestinal motility is a key factor in readiness of the preterm neonates for enteral nutrition. Since gastric motility mainly depends on the electrical activity of the smooth muscle cells, it was of interest to investigate the developmental aspects of electrical activity of the stomach. The latter was recorded weekly through cutaneous electrogastrography in 27 preterm infants (aged 29-34 weeks of gestation). Recordings were done for 1 hr before and 1 hr after meal. The electrogastrographic variables measured were: percentage of normal gastric rhythm, ie, 2-4 cpm; percentage of tachygastria (>4 cpm); the fed-to-fasting ratio of the dominant electrogastrographic power; and the instability coefficient of the dominant frequency. Data were compared with those measured in 10 full-term infants. Peaks of normal electrical activity (2-4 cpm) were present in most of the recordings at all the gestational ages; however, percentages of both normal electrical rhythm and tachygastria in preterm infants were similar to those measured in full-term infants (mean +/- SD) (normal rhythm; fasting: 70.2 +/- 3.8, fed: 72.2 +/- 5.0; tachygastria: fasting: 24.6 +/- 4.0, fed: 19.1 +/- 3.5) by 35 weeks of gestation (normal rhythm; fasting: 67.5 +/- 2.0, fed: 69.6 +/- 4.4; tachygastria: fasting: 27.1 +/- 4.0, fed: 25.6 +/- 4.1). The coefficient of instability of the dominant frequency in preterm infants was also similar to the value measured in full-term infants by 35 weeks of gestation, whereas the EGG power showed a significant increase in the postprandial state at all the gestational ages. We conclude that a maturation pattern of the electrical activity of the stomach can be detected by means of a noninvasive tool such as cutaneous electrogastrography: a normal electrical rhythm can be detected at very early gestational ages; however, this activity becomes dominant at around the 35 weeks of gestational age. In preterm infants developmental changes of gastric electrical activity are a function of advancing postnatal age.

Gastric emptying delay and gastric electrical derangement in IDDM.

OBJECTIVE: Patients with diabetes can develop gastrointestinal motor complications; however, prevalence of gut dysmotility in children with diabetes is poorly understood. We measured gastric emptying time and gastric electrical activity in children with IDDM; presence of dyspeptic symptoms was also assessed. RESEARCH DESIGN AND METHODS: Gastric emptying time and gastric electrical activity were measured by ultrasonography and electrogastrography (EGG), respectively, in 40 consecutive IDDM children (median age: 9 years [6-14]) without autonomic neuropathy; 15 healthy children (median age: 7 years [4-15]) served as control subjects. The EGG variables studied were percent of electrical dysrhythmias (bradygastria or 0.5-2.0 cpm, tachygastria or 4.0-9.0 cpm; normal rhythm is 2.0-4.0 cpm) and fed-to-fasting ratio of the dominant EGG power. Blood glucose level in the fasting state and 180 min after feeding and HbA1C concentration were also measured. Data are given as median (ranges) and means +/- SD. Statistical analysis was performed using the parametric t test and the nonparametric signed-rank tests, with P < 0.05 considered significant. RESULTS: Gastric emptying time was delayed in 26 patients (group A), whereas in 14 patients (group B), it was in the same range as control values; group A patients significantly differed from group B for increased prevalence of gastric electrical dysrhythmias (P < 0.01) and for a lower fed-to-fasting ratio of the dominant EGG power (P < 0.01). Group B patients did not differ from control subjects for the EGG variables measured. Diabetic children with gastroparesis had significantly higher levels of both HbA1C and blood glucose measured 180 min after feeding than those with normal gastric emptying time (P < 0.05); there was a significant correlation between levels of HbA1C and degree of gastric emptying delay, whereas a significant inverse correlation between gastric emptying time and fed-to-fasting ratio of the dominant EGG power was found both in patients and control subjects. CONCLUSIONS: Delay of gastric emptying time and gastric electrical abnormalities are found in a high proportion of children with diabetes and can contribute to poor glycemic control, most likely by causing a mismatch between the onset of insulin action and the delivery of nutrients into the small intestine. Diabetic children with unexplained poor glycemic control should be investigated for abnormalities in gastric motility.

Gastric electrical dysrhythmias and delayed gastric emptying in gastroesophageal reflux disease.

OBJECTIVE: Deranged gastric motility and delayed gastric emptying are commonly implicated in the pathophysiology of gastroesophageal reflux disease. We measured gastric electrical activity and gastric emptying time of a solid-liquid meal by electrogastrography and antral ultrasound, respectively, in 42 patients with gastroesophageal reflux disease (age 7.4 +/- 1.6 yr). METHODS: Based on endoscopy and histology of the esophageal mucosa, reflux disease was moderate in 20 patients and severe in 22. Electrogastrography was measured by placing two Ag-AgCl electrodes on the epigastric skin, signals were digitized and fed into a personal computer, and data were obtained by running spectrum analysis. The electrogastrographic variables calculated were: 1) percent of electrical dysrhythmias and normal electrical rhythm (bradygastria or 0.5-2.0 cycles/min, tachygastria or 4.0-9.0 cycles/min; normal rhythm is 2.0-4.0 cycles/min); 2) fed:fasting ratio of dominant electrogastrographic power; 3) fed:fasting ratio of the dominant frequency instability coefficient. Gastric emptying time and electrical activity results were compared with those measured in 15 controls (7.1 +/- 1.7 yr). RESULTS: Dysrhythmic episodes were more common in both groups of patients than in controls (p < 0.01); furthermore, gastric emptying time was significantly more delayed in patients than in controls (p < 0.01). Children with severe gastroesophageal reflux were distinguished from those with moderate disease for post-feeding gastric electrical abnormalities consisting of reduced electrogastrographic dominant power and increased frequency variability (p < 0.01), as well as for a more prolonged gastric emptying time (p < 0.05). Prevalence of both normal electrical rhythm and dysrhythmias did not discriminate the two groups of patients. In patients and in controls, a significant inverse correlation between fed electrogastrographic power and gastric emptying time was found (r -0.88, p < 0.01). CONCLUSIONS: Fed gastric electrical abnormalities consisting of reduced dominant power and increased variability of the electrical dominant frequency are detected in patients with severe gastroesophageal reflux disease and are associated with delayed gastric emptying. Gastric electrical dysrhythmias may be included among the pathogenetic components of gastroesophageal reflux disease.

Use of a new thickened formula for treatment of symptomatic gastrooesophageal reflux in infants.

BACKGROUND: Paediatricians are familiar with infants complaining of regurgitation and emesis from gastrooesophageal reflux. These subjects, usually growing satisfactorily and healthy, are affected by "functional" or "symptomatic" gastrooesophagel reflux and are treated with posture changes and thickened feedings. AIM: To evaluate in infants with symptomatic gastrooesophageal reflux the effect of a new formula (Nutrilon AR), containing carob flour/locus bean gum as a thickening agent; both clinical features and oesophageal acid exposure were evaluated. PATIENTS: Twenty-four infants (age range: 5-11 months; median age: 8 months; 8 females) presented at our Unit with a history of chronic postprandial regurgitation. METHODS: During a 24-hour intraoesophageal pH test a traditional formula thickened with rice flour at a concentration of 5% was alternated with the formula Nutrilon AR; thereafter infants were randomly allocated to receive, for two weeks, either a traditional thickened formula or the new formula, in addition to posture changes. RESULTS: Intraoesophageal acid exposure was significantly lower in the periods following the new formula than after traditional formula; at the end of the treatment period patients receiving the new formula had a more significant decrease of both symptomatic score and number of episodes of emesis than patients on traditional formula. CONCLUSIONS: The new available formula, with the characteristics of a thickened meal, is better than a formula, traditionally thickened with added rice flour, in the conservative treatment of infants with symptomatic gastrooesophageal reflux.

Antroduodenal motor effects of intravenous erythromycin in children with abnormalities of gastrointestinal motility.

BACKGROUND: The macrolide antibiotic erythromycin (EM) affects gastrointestinal motor activity by acting as agonist of motilin receptors located on the smooth muscle cells of the gastroduodenal tract. We studied the effect of intravenous EM on fasting antroduodenal motility in controls and children with gastrointestinal dysmotility. METHODS: EM lactobionate (rate, 3.0 mg/kg/h) was infused intravenously while antroduodenal manometry was recorded in 10 controls, in 7 patients with functional dyspepsia and in 6 patients with gut pseudo-obstruction. The mean (SD) age (years) was 5.7 (1.4), 6.5 (2.4), and 6.7 (3.2), respectively. Manometry was performed by means of a four- or six-lumen catheter introduced through the nose and perfused with a low compliance pneumohydraulic system. Five controls received EM and five received saline. RESULTS: EM, infused 5 minutes after passage of an activity front (AF), induced in controls a premature antroduodenal AF occurring 15.4 +/- 3.2 minutes after starting infusion; no motor changes were seen after saline; duration and propagation velocity of EM-induced AFs did not differ from spontaneous AFs. In patients with functional dyspepsia EM induced various patterns such as premature antroduodenal AFs, antral phase III-like pattern with short duodenal bursts or prolonged phasic antral waves and no duodenal activity. In patients with neurogenic pseudo-obstruction rare or absent antral activity with incoordinated or absent duodenal activity was induced; no contractions were elicited in two patients with myogenic pseudo-obstruction. CONCLUSIONS: It is confirmed that EM, given at subtherapeutic doses, is a powerful prokinetic agent that can have clinical applications in patients with gastrointestinal dysmotility; however, the effect of the drug seems to be influenced by the nature of the underlying disorder.

Effects of omeprazole on mechanisms of gastroesophageal reflux in childhood.

Prolonged recordings of esophageal motility have shown that dynamic changes of lower esophageal sphincter (LES) pressure such as transient LES relaxation and LES pressure drifts are the most common mechanisms underlying gastroesophageal reflux (GER). The coexistence of a delayed gastric emptying has also been reported in a high proportion of patients with reflux disease. However, not much information is available on the effects of antireflux therapy on the pathogenetic mechanisms of GER. The purpose of this study was to determine in a group of children with severe reflux disease the effect of omeprazole therapy on motor changes of LES underlying GER as well as on gastric emptying time. Twenty-two children (median age: 6.6 years) with GER disease, refractory to combined ranitidine and cisapride administration, entered into an eight-week omeprazole course. Ten subjects with moderate GER disease served as controls (median age: 6.0 years). Before and after omeprazole administration, the following variables were assessed: esophagitis grading, fasting and fed simultaneous prolonged recording of distal esophageal sphincter pressure (with a sleeve catheter) and intraesophageal pH, LES and esophageal peristalsis amplitude, and gastric emptying time of a mixed solid-liquid meal (measured with gastric ultrasound). As compared to controls, patients showed a higher rate of transient LES relaxation and LES pressure drift (P < 0.01), a reduced amplitude of basal sphincter pressure (P < 0.01) and peristalsis (P < 0.05), and a more prolonged gastric emptying time (P < 0.05). After ending omeprazole, there was no significant change in any of the motor abnormalities of the esophagus and in gastric emptying time despite a marked improvement of symptoms and esophagitis in all patients. Sixteen patients were symptomatic when reevaluated on a clinical basis two months after ending therapy. We conclude that in children with severe GER disease, an abnormally high rate of both transient LES relaxation and LES pressure drift and slow gastric emptying are not affected by omperazole treatment, even though esophageal mucosal damage is markedly improved or cured. These abnormalities represent a primary motor disorder and can be implicated in the refractoriness of reflux disease.

Helicobacter pylori gastritis and non-ulcer dyspepsia in childhood. Efficacy of one-week triple antimicrobial therapy in eradicating the organism.

Efficacy of one-week triple antimicrobial therapy (bismuth, tinidazole, amoxicillin) as compared to the same drug combination given for 4 weeks was assessed in children with Helicobacter pylori (H. pylori) gastritis and non-ulcer dyspepsia. Twenty-six patients (group A) and 30 (group B) had one-week and four-week schedule, respectively. Eradication (absence of organism at endoscopy at least 1 month after ending treatment) was achieved in 84.6% of group A (22) and 83.3% of group B (25), with marked reduction of histological gastritis score in both groups. Among patients with eradicated H. pylori, symptoms improved significantly in 14 and 16 patients of group A and B, respectively, but were still present in 17 (8 group A, 9 group B). The latter showed gastroparesis and abnormal gastro-oesophageal reflux at a subsequent diagnostic work-up and improved with prokinetic therapy. In 3 patients of group A and 3 of group B, symptoms improved despite persistence of bacterium into the stomach. Finally, in 3 cases (1 group A, 2 group B) both symptoms and H. pylori infection were unchanged. At 6 month follow-up, symptoms were present in 7 patients (3 group A, 4 group B): 6 of them (3 group A, 3 group B) showed H. pylori gastritis at endoscopy. We conclude that in children with dyspepsia and H. pylori gastritis one-week triple antimicrobial schedule is effective in eradicating bacterium; however, detection of H. pylori gastritis in dyspeptic children does not invariably indicate a pathogenic role of the organism in these patients.

[Severe chronic constipation: limitations of medical therapy and indications for surgical intervention (diagnostic and therapeutic). I]. / Stipsi cronica severa: limiti della terapia medica e indicazioni all'intervento chirurgico (diagnostico e terapeutico). Parte prima.

The great majority of children referred to Pediatric Gastroenterologic Units for chronic constipation have a functional disorder and do not require investigative techniques, since functional constipation is easily recognized an anamnestic and clinical basis. Severe chronic constipation indicates a chronic condition believed to be of functional type but unresponsive to the traditional pharmacologic treatment. However, several clinical features might suggest an organic type of constipation during the initial diagnostic approach: growth failure, distension, episodes of diarrhea intermingled with constipation, subocclusive events, dilatation of areas of the gut (megaduodenum, megajejunum) at x-ray examination of the entire gastrointestinal tract. Hirschsprung's disease is the best known organic type of constipation; however, there are other neurogenic and myogenic abnormalities of the colonic (and/or ileal) tract that mimick Hirschsprung's disease and represent development abnormalities of the enteric nervous plexus. Other organic types of constipation are due to systemic diseases, endocrine and metabolic disorders, central nervous system disorders. Organic constipation usually requires extensive investigative approach, including pathologic examination of enteric nervous plexus on full thickness biopsies.

[Infected bowel syndrome]. / Sindrome dell'intestino infetto.

Colonization of the gut by intestinal bacteria begins at birth and progresses rapidly in the immediate postnatal period. Host defense mechanisms that mediate enteric colonization include gastric acidity and intestinal motility. The small bowell overgrowth syndrome is a condition characterized by large numbers of bacteria, often anaerobes, in the upper intestine. Steatorrea, carbohydrate malabsorption and abdominal pain are frequently present. Predisposing conditions are localized anatomic disorders (surgical blind loops, small bowel strictures caused by surgery or Crohn's disease, short-gut syndrome without ileocaecal valve), motility derangements or reduction of gastric acidity. Diagnosis of the overgrowth syndrome is often difficult and quantitative cultures of jejunal-aspirated fluid is the best diagnostic test. Antimicrobial therapy directed against anaerobes is often successful, but the best therapeutic approach is the correction of predisposing conditions, if present.

Simultaneous prolonged recordings of proximal and distal intraesophageal pH in children with gastroesophageal reflux disease and respiratory symptoms.

OBJECTIVES: To characterize both proximal and distal esophageal acid exposure in children with gastroesophageal reflux-related respiratory disease and to investigate the usefulness of dual-channel intraesophageal pH monitoring in these patients. METHODS: Continuous simultaneous recording of distal and proximal esophageal pH was performed in 40 patients with gastroesophageal reflux disease and respiratory symptoms (wheezing, nocturnal cough, obstructive bronchitis) (age range 3-168 months) (group A), in 20 patients with reflux disease alone (age range 7-156 months) (group B), and in 14 controls (age range 5-108 months) (group C). RESULTS: (expressed as median +/- SD) 1) The two groups of patients did not differ with regard to distal and proximal esophageal acid exposure (percentage of reflux) during both the total recording period [distal, A: 9.2 +/- 4, B: 10.7 +/- 7 (NS), C: 1.9 +/- 1.0; and proximal, A: 4.8 +/- 3.3, B: 4.0 +/- 3.3 (NS), C: 1.0 +/- 0.7] and during nighttime [distal, A: 8.0 +/- 6.2, B: 10.4 +/- 6.1 (NS), C: 0.9 +/- 0.65; and proximal, A: 3.72 +/- 3, B: 3.6 +/- 3.0 (NS), C: 0.75 +/- 0.45]. 2) The two groups did not differ with regard to the ratio between proximal and distal esophageal acid exposure during both total and nocturnal periods of analysis. 3) No significant correlation was found between distal and proximal esophageal acid exposure during total and nocturnal recording periods. 4) In patients with reflux-related respiratory disease, the respiratory symptomatic index was significantly higher during distal esophageal acid exposure alone (47.0 +/- 28.6%) than during simultaneous reflux at the two esophageal levels (26.9 +/- 27%) (p < 0.05). Furthermore, reflux episodes associated with respiratory symptoms reached lower pH values than those in patients without symptoms at the two recording sites. CONCLUSIONS: Gastroesophageal reflux into the proximal esophagus does not discriminate between patients with reflux disease alone and those with reflux disease complicated by respiratory symptoms. Symptoms of asthma in reflux patients appear to be elicited more by a reflex mechanism than by aspiration of gastric refluxate into the airways. Intraesophageal acidification seems to be involved in eliciting respiratory symptoms related to reflux disease, and prolonged intraesophageal two-level pH measurement does not seem to be useful in the approach to patients with reflux disease associated with respiratory symptoms.

Multicenter comparative study of aztreonam and gentamicin in the treatment of renal and urinary tract infections.

A multicenter comparative study was carried out to evaluate the efficacy of aztreonam and gentamicin in 186 patients with symptomatic renal or urinary tract infections. Patients were divided randomly into two groups: 94 patients received aztreonam 1 g/day intramuscularly and 92 patients received gentamicin 80 mg i.m. twice daily. The clinical and microbiologic results found a single daily dose of aztreonam to be more effective than gentamicin b.i.d. Furthermore, no evidence of side effects was seen with aztreonam. Such results are generally thought to ensure better compliance in outpatients.