Methodology and indications of H2-breath testing in gastrointestinal diseases: the Rome Consensus Conference

BACKGROUND

Breath tests represent a valid and non-invasive diagnostic tool in many gastroenterological conditions. The rationale of hydrogen-breath tests is based on the concept that part of the gas produced by colonic bacterial fermentation diffuses into the blood and is excreted by breath, where it can be quantified easily. There are many differences in the methodology, and the tests are increasingly popular.

AIM

The Rome Consensus Conference was convened to offer recommendations for clinical practice about the indications and methods of H2-breath testing in gastrointestinal diseases.

METHODS

Experts were selected on the basis of a proven knowledge/expertise in H2-breath testing and divided into Working Groups (methodology; sugar malabsorption; small intestine bacterial overgrowth; oro-coecal transit time and other gas-related syndromes). They performed a systematic review of the literature, and then formulated statements on the basis of the scientific evidence, which were debated and voted by a multidisciplinary Jury. Recommendations were then modified on the basis of the decisions of the Jury by the members of the Expert Group.

RESULTS AND CONCLUSIONS

The final statements, graded according to the level of evidence and strength of recommendation, are presented in this document; they identify the indications for the use of H2-breath testing in the clinical practice and methods to be used for performing the tests.

Gastric emptying of a solid meal is accelerated by the removal of dietary fibre naturally present in food

Exogenous fibre added to liquid meals delays gastric emptying. Its effect on solid meals is uncertain, and nothing is known of the effect on gastric emptying of fibre naturally present in food. This study therefore looked at gastric emptying of two different solid meals in eight healthy subjects and their blood glucose responses. The meals were exactly equivalent except for the total dietary fibre content (high fibre 20 g, low fibre 4 g of dietary fibre per 1000 kcal) and supplied 870 kcal (700 kcal women), 47% of which was from carbohydrates, 36% from fats, and 17% from proteins. Ultrasonography was used to measure antral diameters before the meal (basal), immediately after it (time 0), and at 30, 60, 120, 180, 240, and 300 minutes. In addition, subjects filled in a questionnaire on their feelings of hunger, epigastric fullness, and satiety before the meal and at hourly intervals after it. Basal and maximal postprandial antral sections were similar for the two meals (basal section: 283.9 (29.5) v 340.9 (44.7) mm2 for the low and the high fibre meal, NS; maximal postprandial section: 1726 (101.9) v 1593 (120.4) mm2, NS). Total gastric emptying time was significantly reduced by fibre removal (186.0 (15.6) v 231.7 (17.3) minutes after the low and the high fibre meal, p < 0.05). Blood glucose was higher after the low fibre meal, and the area under the glycaemic curve significantly greater (226 (23.1) v 160 (20.0) mmol/min/dl-1, p < 0.05). No difference was found in satiety or fullness feelings, but hunger returned more rapidly after the low fibre meal. In conclusion, fibre naturally present in food delays gastric emptying of a solid meal, reduces the glycaemic response, and delays the return of hunger.

Survival rate and prognostic factors in patients with intestinal failure

BACKGROUND

Intestinal failure impairs nutritional status and survival expectance. Though intestinal adaptation and enteral independence may be achieved, artificial nutrition is needed in about half of the patients.

AIMS

This study is aimed at assessing the causes of death, survival rate, enteral independence in time, and factors affecting the clinical outcome in a group of patients with intestinal insufficiency.

PATIENTS

Sixty-eight patients with intestinal insufficiency, due to major intestinal resection in 60 cases (short bowel syndrome) (remnant intestine length 101-150 cm in 31 cases, 50-100 cm in 23 cases, <50 cm in 6 cases), and due to chronic idiopathic pseudo-obstruction in 8 cases, were enrolled and followed-up for (median) 36 months (25th and 75th percentile in 12 and 60 months, respectively). In 60 short bowel syndrome patients, the main conditions that led to intestinal failure were ischemic bowel (28), major surgery complications or severe adhesions (17), radiation enteritis (10), Chron's disease, intestinal tuberculosis, small bowel lymphoma and trauma (others).

METHODS

Seventeen variables age, underlying disorders, length of remnant bowel, type of surgery, hospital stay, type of nutrition (hospital and home) and its variations in time, causes of death, survival rate and time were considered. Statistical analysis was carried out by Mann-Whitney U-test, Pearson chi2, Spearman correlation test, Kaplan-Meyer method and Cox's proportion hazards regression model.

RESULTS

At the time of admission to the hospital, none of the patients had nutritional independence, 54 (79.4%) were on parenteral nutrition and 14 (20.6%) were on enteral nutrition. At the time of discharge, 23 (33.8%) patients showed enteral independence, 39 were on home parenteral nutrition, 3 on enteral nutrition + i.v. feeding, 1 on enteral nutrition, and 2 needed oral supplementation with hydroelectrolyte solutions only. After a median value of 36 months, 30 and 2 patients were on home parenteral nutrition and enteral nutrition + i.v. feeding, respectively, 2 on enteral nutrition, 2 on oral supplementation with hydroelectrolyte solutions, and 26 cases reached enteral independence. A significant relationship was detected between the length of remnant bowel and types of nutrition at both admission (r = 0.38; P = 0.001) and discharge (r = 0.48; P = 0.001), parenteral nutrition being more frequent in patients with very short bowel. Twenty-two patients (32.4%) died (4 from newly occurring malignancies), 40 (58.8%) survived, and 6 (8.8%) were lost to the follow-up. Eleven of 22 patients died from conditions related to intestinal failure (8 cases) and/or home parenteral nutrition complications (3 cases). At 12, 24, 36, 48, 60 and 72 months, survival rates were 95.4, 93.3, 88.1, 78.6, 78.6 and 65.5%, respectively, but it was significantly lower for patients with <50 cm of remnant bowel than those with longer residual intestine (P < 0.05), and in patients who started home parenteral nutrition above the age of 45 years (P < 0.02). Survival rate was higher in patients with enteral independence than those with enteral dependence (P < 0.05). Better survival rates were registered in patients with chronic obstructive intestinal pseudo-obstruction and major surgery complications, whereas ischemic bowel and even more radiation enteritis were associated with a lower survival expectance.

CONCLUSIONS

Actuarial survival rate of patients with intestinal failure quotes 88 and 78% at 3 and 5 years, respectively. It is influenced by the length of remnant intestine, age at the start of home parenteral nutrition, enteral independence and, to some extent at least, by the primary disorder. Enteral independence can be achieved in time by about 40% of the patients with intestinal insufficiency, but for home parenteral nutrition-dependent cases, intravenous feeding can be stopped in less than one out of five patients during a median 3-year period.

Tussive effect of capsaicin in patients with gastroesophageal reflux without cough

The aim of this study was to clarify the influence of gastroesophageal reflux (GER) on cough threshold in patients with digestive symptoms but free from respiratory involvement. Of 57 consecutive subjects referred for 24-h esophageal pH monitoring because of digestive reflux symptoms, 29 patients free from respiratory disorders were studied. They underwent esophageal pH monitoring and manometry, upper gastrointestinal endoscopy, pulmonary function tests, and methacholine and capsaicin challenges. The methacholine test was performed by inhalation of increasing doses of methacholine up to 4,000 micrograms; the results were expressed as the dose causing a 20% decrease in FEV1 from baseline (PD20). The capsaicin threshold was evaluated by inhalation of increasing doses of capsaicin from 0.3 up to 9.84 nmol, expressing the results as the dose of capsaicin eliciting five coughs (PD5). Fifteen patients were considered refluxers on the basis of a total esophageal acid exposure time above 4.7%. Esophagitis grade 0 was found in 15 patients, grade 1 in seven patients, grade 2 in seven patients. PD5 was significantly lower in refluxers (median 0.51 micrograms, range 0.22 to 19.8) than in nonrefluxers (19.8 micrograms, range 0.31 to 19.8) (p < 0.001); there was no difference in baseline ventilatory parameters and in airway responsiveness to methacholine between the two groups. All patients with a pathologic acid exposure time but one had a low cough threshold, irrespective of the presence or absence of esophagitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Simultaneous measurement of gastric emptying of a solid meal by ultrasound and by scintigraphy

OBJECTIVE

Although ultrasonic imaging may represent a valid alternative to scintigraphy for measurement of gastric emptying, most studies comparing the two methods have been carried out with liquid meals. The aim of this study was to compare scintigraphic and ultrasonographic measurements of gastric emptying of a solid meal in healthy subjects and in patients with possible delay in emptying.

METHODS

Nineteen subjects were studied: five controls, six patients with gastroesophageal reflux, and eight patients with dysmotility-like dyspepsia. Gastric emptying was measured by both scintigraphy and ultrasonography after ingestion of an 800-calorie solid, realistic meal containing 99mTc-labeled chicken liver. Scintigraphic measurements were made every 15 min for 6 h, and ultrasonic imaging of antral sections was undertaken every 15 min for the first 1 h and every 30 min thereafter. Total emptying times were calculated independently using the two methods, and the emptying patterns recorded by the two methods were compared.

RESULTS

Maximal antral dilation occurred 30 min (range 0-90 min) after the end of the meal and persisted until 96 +/- 42 min, by which time gastric radioactivity had decreased from its maximum by 43% +/- 23%. From this time on, the antral cross-sectional area returned toward the basal value, declining faster than the gastric counts recorded by scintigraphy. Total emptying times measured by ultrasound and by scintigraphy were in good agreement in all subjects, with a mean difference of only 4.5 min (limits of agreement, -17.1 to 21.6 min).

CONCLUSIONS

Ultrasonographic measurement of antral cross-sectional area provides a valid alternative to scintigraphy for the measurement of total gastric emptying of a solid meal. It is less reliable if other parameters of gastric emptying such as T(1/2) are required.

Cough threshold in reflux oesophagitis: influence of acid and of laryngeal and oesophageal damage

BACKGROUND

Gastro-oesophageal reflux is often associated with cough. Patients with reflux show an enhanced tussive response to bronchial irritants, even in the absence of respiratory symptoms.

AIM

To investigate the effect of mucosal damage (either oesophageal or laryngeal) and of oesophageal acid flooding on cough threshold in reflux patients.

PATIENTS

We studied 21 patients with reflux oesophagitis and digestive symptoms. Respiratory diseases, smoking, and use of drugs influencing cough were considered exclusion criteria.

METHODS

Patients underwent pH monitoring, manometry, digestive endoscopy, laryngoscopy, and methacholine challenge. We evaluated the cough response to inhaled capsaicin (expressed as PD5, the dose producing five coughs) before therapy, after five days of omeprazole therapy, and when oesophageal and laryngeal damage had healed.

RESULTS

In all patients spirometry and methacholine challenge were normal. Thirteen patients had posterior laryngitis and eight complained of coughing. Twenty patients showed an enhanced cough response (basal PD5 0.92 (0.47) nM; mean (SEM)) which improved after five and 60 days (2.87 (0.82) and 5.88 (0.85) nM; p<0.0001). The severity of oesophagitis did not influence PD5 variation. On the contrary, the response to treatment was significantly different in patients with and without laryngitis (p = 0.038). In patients with no laryngitis, the cough threshold improved after five days with no further change thereafter. In patients with laryngitis, the cough threshold improved after five days and improved further after 60 days. Proximal and distal oesophageal acid exposure did not influence PD5. Heartburn disappeared during the first five days but the decrease in cough and throat clearing were slower.

CONCLUSIONS

Patients with reflux oesophagitis have a decreased cough threshold. This is related to both laryngeal inflammation and acid flooding of the oesophagus but not to the severity of oesophagitis. Omeprazole improves not only respiratory and gastro-oesophageal symptoms but also the cough threshold.

DNA detection by integrable electronics

This paper presents a new electronic methodology to detect DNA hybridization for rapid identification of diseases, as well as food and environmental monitoring on a genetic base. The proposed solution exploits a new (electrical) capacitive measurement circuit, not requiring any prior labeling of the DNA (as it is often the case with the commonly employed optical detection). The sensitivity, the reliability, and the reproducibility of this device have been evaluated by experiments performed with a (non-integrated) prototype implementation, easily integrable in IC and/or micro-fabricated lab-on-a-chip.

A clinical evaluation of monoclonal (CA19-9, CA50, CA12-5) and polyclonal (CEA, TPA) antibody-defined antigens for the diagnosis of pancreatic cancer

We measured in 193 patients, admitted to our wards for symptoms and signs suggestive of pancreatic or digestive malignancy, the serum levels of five tumor-associated antigens (CA 19-9, CA 50, CA 125, TPA, CEA) and we evaluated their diagnostic accuracy both when used alone and in combination. For CA 19-9 and CA 50 a sensitivity for pancreatic cancer as high as 92 and 88%, respectively, and specificity of 91.8% were found. A lower sensitivity vs. pancreatic cancer was found for the other tumor markers, and vs. the other digestive and nondigestive malignancies for all tumor markers (apart for CA 19-9 and CA 50 vs. biliary carcinomas). As for the combined assays, the best figures were found vs. pancreatic cancer for CA 19-9 plus CA 50, CA 50 plus CEA, CA 50 plus CA 125; a sensitivity by far worse vs. the other gastrointestinal cancers was found for all the possible combinations. We conclude that in selected symptomatic patients some tumor-marker determinations can be useful in identifying those with a high probability of harboring a pancreatic cancer, to be further studied or operated upon. The clinical relevance of this in patients already symptomatic is at present unclear.

Near infrared spectrometry for faecal fat measurement: comparison with conventional gravimetric and titrimetric methods

This investigation was aimed at comparing a new method for measuring faecal fat excretion, carried out with a semi-automated instrument by using near infrared analysis (NIRA), with the traditional titrimetric (Van de Kamer) and gravimetric (Sobel) methods. Near infrared analysis faecal fat was assayed on the three day stool collection from 118 patients (68 chronic pancreatitis, 19 organic diseases of the gastrointestinal tract, 19 alcoholic liver disease, 12 functional gastrointestinal disorders). A strict linear correlation was found between NIRA and both the titrimetric (r = 0.928, p less than 0.0001) and the gravimetric (r = 0.971, p less than 0.0001) methods. On homogenised faeces, a mean coefficient of variation of 2.1 (SD 1.71)% was found. Before homogenisation (where a mean coefficient of variation of 7% was found) accurate results were obtained when the mean of five measurements was considered. In conclusion, the assay of faecal fat excretion by the near infrared reflessometry appears a simple, rapid and reliable method for measuring steatorrhoea.

Omeprazole causes delay in gastric emptying of digestible meals

We have studied gastric emptying of a solid, realistic meal (800 cal, 15% protein, 45% fat, 40% carbohydrate) in 21 healthy subjects twice, with and without a four-day pretreatment with 40 mg omeprazole. The last dose of the drug was taken 24 hr before the test, to avoid hypothetical nonsecretory side effects of the drug . Gastric emptying was measured by ultrasound of antral diameters. The results show that basal and maximal postprandial antral cross-sectional areas were the same during the two tests. A greater residual distention of the antrum was present throughout the study after the omeprazole treatment, the difference being significant at time 120 and 240. Omeprazole induced a highly significant delay in gastric emptying [control 199.6 (12.6) vs omeprazole 230.9 (12.7) min, mean (1 SEM); P<0.003]. The delay was not due to a prolonged lag phase, but rather to an effect on the slope of the emptying curve. This study shows that in normal subjects omeprazole delays gastric emptying of a digestible solid meal.

Prokinetic effect of gut-oriented hypnosis on gastric emptying

BACKGROUND

No data are available on the effect of hypnosis on gastric emptying.

AIM

To determine the effect of a hypnosis session on gastric emptying and dyspeptic symptoms.

METHODS

We studied emptying by ultrasonography and epigastric sensations in 11 healthy subjects and in 15 patients affected by functional dyspepsia under three conditions according to a fixed schedule: (a) basal, (b) after cisapride and (c) during a 90 min hypnotic trance. Eight healthy subjects repeated an emptying study listening to relaxing music. Statistical analysis was performed using the Friedman test or RM-ANOVA.

RESULTS

In dyspeptics, the postprandial increase in the antral area was significantly smaller during the hypnosis trance than under the basal and the cisapride conditions. For the patients gastric emptying was significantly shortened by cisapride, and even more by hypnosis (basal 274 +/- 16.8 min; cisapride 227 +/- 13.2; hypnosis 150 +/- 9.7) whereas for healthy subjects it was shortened only by hypnosis. The repeated study in healthy subjects listening to relaxing music showed no significant difference compared with the basal. Epigastric sensations were improved in dyspeptics by hypnosis, but not by cisapride.

CONCLUSIONS

Gut-oriented hypnosis is effective in shortening gastric emptying both in dyspeptic and in healthy subjects.

Medium-chain triglyceride absorption in patients with pancreatic insufficiency

BACKGROUND

The role of medium-chain triglycerides (MCTs) in the management of patients with pancreatic insufficiency is controversial. The aim of the study was to evaluate the absorption of MCTs in the presence of pancreatic insufficiency and the effect of pancreatic extracts on MCT absorption so as to clarify whether the replacement of usual dietary fats with MCTs is cost-effective.

METHODS

Six patients with severe pancreatic steatorrhea were for 5 days fed a low-fat diet to which butter (long-chain triglycerides (LCTs)) or MCT oil was added, with and without pancreatic extracts, in a crossover design.

RESULTS

Fecal weight and nitrogen losses were the same during MCT and LCT intake. Steatorrhea was substantial during both periods but was significantly lower during MCT than LCT intake. Fecal weight and nitrogen and fat losses were reduced by pancreatic extracts in both diets. Steatorrhea was the same when MCTs and LCTs were consumed together with pancreatic extracts.

CONCLUSIONS

MCTs are absorbed better than LCTs in the presence of pancreatic insufficiency but require pancreatic extracts for optimal absorption. No advantage is to be expected from replacing usual dietary fats with MCTs if pancreatic supplements are used.

Gastric emptying of solids is markedly delayed when meals are fried

We studied the effect of heat-treated fats on gastric emptying. Eight healthy asymptomatic volunteers (five males; age 28-41 years) ate on different days and in random order two meals identical in contents (pasta, tomato, beef, olive oil, carrots, orange, water; 870 kcal males, 700 kcal females; 47% of calories from carbohydrate, 36% from fat, 17% from protein), but cooked differently (fats fried or not). Ultrasound measurement of antral diameters was used to calculate basal antral section, its maximal dilation after the meal, the time necessary for total emptying, and the percent retention at hourly intervals. No difference was found in basal and maximal antral diameters after the two meals. On the contrary, total gastric emptying was significantly delayed after the fried meal [317.1 (24.12) vs 226.7 (18.4) min, mean (1 SEM); P < 0.002]. A significantly greater percentage of maximal antral distension was still present between 120 and 240 min after the fried meal. The glycemic response and hunger feeling were the same after the two meals, whereas there was a longer persistence of satiety and epigastric fullness after the fried meal. In conclusion, gastric emptying can be influenced not only by the meal content, but also by the way it is cooked.

The effect of breakfasts varying in glycemic index and glycemic load on dietary induced thermogenesis and respiratory quotient

BACKGROUND AND AIM

Glycemic index (GI) and Glycemic Load (GL) are parameters of carbohydrate bioavailability able to influence risk of chronic diseases. GL can be lowered either by reducing carbohydrate intake or by reducing the GI of the carbohydrate moiety of a mixed meal. These two approaches might have a different impact on Dietary-Induced Thermogenesis (DIT) and preferential substrate oxidation in the postprandial period, which are variables known to be involved in the regulation of body weight and body composition. This dietary, crossover intervention trial was designed to evaluate the effect on DIT and Respiratory Quotient (RQ) of three isocaloric breakfasts different in GI and/or GL (high GI and high GL [HGI-HGL] vs. low GI and low GL [LGI-LGL]; vs. high GI and low GL [HGI-LGL]) followed by a standard meal.

METHODS AND RESULTS

RQ and DIT were measured in 16 lean young males by indirect calorimetry for 8h. DIT resulted significantly higher after the LGI-LGL compared to the HGI-HGL breakfast (p<0.05). Postprandial changes in RQ differed among all breakfasts (p<0.001). RQ increased from baseline after the two breakfasts with highest carbohydrate content and significantly more after the HGI-HGL than after the LGI-LGL (p<0.02), whereas it decreased after the HGI-LGL breakfast, which contained a higher amount of fat.

CONCLUSIONS

Reducing the GL of a meal by reducing GI seems an effective strategy to increase energy expenditure while maintaining a good rate of lipid oxidation. This might be related to different profiles of postprandial hormones affecting substrate oxidation.

Is the 14C-triolein breath test useful in the assessment of malabsorption in clinical practice?

A 14C-triolein breath test was carried out on 49 subjects suffering from chronic pancreatitis or from other digestive diseases, and its results were compared with the daily fecal fat excretion. The 14CO2 peak excretion was abnormal in all the subjects with a fecal fat excretion above 14 g/day, whereas individual values of 14CO2 peak excretion in subjects without steatorrhea and with a fecal fat excretion ranging from 7.1 to 14 g overlapped. The lowest value observed in patients not suffering from steatorrhea was chosen as the lower normal limit of 14CO2 peak excretion. A test sensitivity as high as 64% was attained. The correlation between fecal fat and 14CO2 peak excretion was highly significant (r = 0.802; p less than 0.0001), and it followed a negative exponential function. Therefore, small variations in the 14CO2 peak excretion can be associated with a wide range of fecal fat excretion. Well-compensated diabetes secondary to pancreatitis did not interfere with the results of the test. In conclusion, in our experience this test proved to be a qualitative diagnostic tool with a low sensitivity.

The fecal chymotrypsin photometric assay in the evaluation of exocrine pancreatic capacity. Comparison with other direct and indirect pancreatic function tests

Fecal chymotrypsin (FCT) has been measured by a new photometric method (Monotest Chymotrypsin; Boehringer, Mannheim) in 78 patients: 44 with chronic pancreatitis and 34 not affected by any pancreatic disease. The results were compared with those from other tests of pancreatic secretory (secretin-cerulein test) and digestive [serum and urinary p-aminobenzoic acid (PABA) and pancreolauryl] capacity. When FCT values were severely reduced (below 6.7 U/g), from 90 to 100% of the patients also presented abnormal pancreatic secretory and digestive capacity. On the other hand, 87% of the patients with normal FCT (above 20 U/g) presented normal secretory and digestive capacity. Patients with intermediate FCT values (between 6.7 and 20 U/g) showed normal or abnormal pancreatic secretory and digestive capacity with the same probability. Therefore, FCT, carried out as a first test, seems to identify subjects that need no further pancreatic function tests (normal and severely impaired FCT) and patients who need other more complex functional investigations (intermediate FCT values).

Pathological esophageal acidification and pneumatic dilitation in achalasic patients. Too much or not enough?

Endoscopy, esophageal manometry and pH monitoring, gastric emptying test, and heartburn quantification on a visual analog scale were performed in 22 achalasic patients in order to clarify which events are associated with pathological esophageal acidification after successful LES dilatation. Five patients presented pathological acidification. Dilatation reduced LES tone from 38.3 +/- 4.2 to 14.6 +/- 1.1 mm Hg (mean +/- SEM); there was, however, no difference between nonrefluxers and refluxers (14.8 +/- 1.2 vs 13.8 +/- 2.5 mm Hg). The emptying time in achalasic patients was delayed compared to controls (315.9 +/- 20.9 min vs 209 +/- 10.4) due to prolonged lag-phase and reduced slope of the antral section-time curve, but, again, there was no difference between refluxers and nonrefluxers. The acid clearance was delayed in refluxers compared to nonrefluxers (15.9 +/- 4.5 vs 2.5 +/- 1.8 min, P<0.05). Two refluxers presented grade 1 esophagitis; one of them developed an esophageal ulcer. The heartburn score was the same in refluxers and nonrefluxers. Pathological acidification after pneumatic dilatation is associated with persistent problems in esophageal emptying rather than with excessive sphincter divulsion.

Near infrared reflectance measurement of nitrogen faecal losses

Chemical methods of measuring nitrogen in stools are complex, unpleasant, and therefore rarely performed. Recently, near infrared reflectance (NIRA) has been suggested for stool analysis. The aim of this study was to evaluate the possible application of this method in routine faecal nitrogen measurement. Nitrogen concentration and daily output were measured in the stools of 83 patients using NIRA and, for comparison, the Kjeldahl method. Nitrogen concentration and output ranged between 0.4-2.72 g% and 0.45-8.96 g/day respectively. Correlation coefficients (r), of 0.89 and 0.97 were found between the two methods for concentration and output respectively, and similar values were found in patients on enteral nutrition. Repeated measurements from the same stool collection, requiring only a few minutes, allowed homogenisation to be avoided. NIRA seems to be an easy, fast, and reliable alternative to chemical assays of nitrogen measurement in the management of patients with digestive disorders.

Serum PABA and fluorescein in the course of Bz-Ty-PABA and pancreolauryl test as an index of exocrine pancreatic insufficiency

Forty-six subjects (20 chronic pancreatitis, 7 chronic liver disease, 7 recovered from acute pancreatitis, 2 Crohn's disease, and 10 healthy controls) classified by S-C test as having normal pancreatic function (26 subjects), or moderate (10 subjects) and severe (10 cases) pancreatic insufficiency, were given, on different days, 1 g of oral PABA or 348 mg of oral fluorescein dilaurate. At the 1st, 2nd, and 4th hours (PABA) and the 2nd, 4th, and 6th hours (fluorescein) serum samples were taken for assay. In the presence of severe exocrine pancreatic insufficiency, the sensitivity of the fluorescein serum levels was higher than that observed for the PABA (100% and 80%, respectively), and quite similar to that shown by the urinary tests (100% and 70%, respectively). On the contrary, in presence of moderate pancreatic insufficiency, both the urinary test (pancreolauryl and (PABA) give a sensitivity higher than that found in the serum tests (30-40% and 10-30%, respectively). The parallel combination of both the serum or urinary tests does not significantly improve the sensitivity of the single test. These results suggest that the serum PABA and serum fluorescein tests can be valid choice when a prolonged urinary collection is difficult, i.e., in children and in elderly patients. However, the slight diagnostic gain does not justify the routine use of both urinary and serum tests.

Gastric emptying of realistic meals with and without gluten in patients with coeliac disease. Effect of jejunal mucosal recovery

BACKGROUND

Few data are available on disturbed gastric emptying in patients with coeliac disease. The aims of the study were to investigate (a) the presence of delayed gastric emptying: (b) the acute effect on gastric emptying of gliadin; and (c) the effect of jejunal recovery on gastric emptying of meals with or without gluten in such patients.

METHODS

We measured gastric emptying of two meals in 16 patients with coeliac disease; one meal contained gliadin. Results were compared with those obtained in 24 controls. In 12 patients, both measurements were repeated after mucosal recovery. Statistical analysis was performed using the analysis of variance for repeated measurements and Student's t test. Mean +/- 1 s(mean) (standard error of the mean) are shown.

RESULTS

No difference was found in fasting and in maximal antral sections after the two meals. On entry, gastric emptying was significantly (P < 0.001) delayed compared to controls both after the meal containing gluten (326.9 +/- 12.4 min versus controls 213.5 +/- 11.5) and after the gluten-free meal (315.3 +/- 16.7 min). After jejunal recovery, emptying of the meal containing gluten remained unchanged (337 +/- 18.9 min), whereas emptying of the gluten-free meal was significantly shortened (280.6 +/- 10.5 min; P < 0.001).

CONCLUSIONS

In coeliac disease there is an impairment of gastric emptying which is at least partially reversible. This suggests either an immunological disorder or that unabsorbed meal constituents are responsible for an ileal-brake effect.

Reliability of the Bz-Ty-PABA and the pancreolauryl test in the assessment of exocrine pancreatic function

The reliability of the para-aminobenzoic acid (PABA) test (performed in the conventional manner, i.e. without control day) and of the pancreolauryl test was assayed in respect of the exocrine pancreatic capacity measured by using the secretin-caerulein test in 57 subjects, 22 of which were suffering from chronic pancreatitis. When 50 and 20% urinary excretion of the orally administered Bz-Ty-PABA and pancreolauryl, respectively, were chosen as the lower normal limits, the PABA test showed a specificity quite similar to that of the pancreolauryl test (97 and 95%, respectively) despite the lack of a control day test, but a lower sensitivity (39 vs. 83%). The association of both tests was not advantageous compared with the pancreolauryl test alone.

Pancreatic extracts are necessary for the absorption of elemental and polymeric enteral diets in severe pancreatic insufficiency

Tube feeding nutrition, either elemental or polymeric, is increasingly used in patients with digestive problems. Pancreatic insufficiency is a widely accepted indication for the use of an elemental formula, which requires less residual digestive capacity. To confirm this assumption, we have compared the absorption of elemental and polymeric diets and the effect of exogenous pancreatic enzymes in a patient on long-term total enteral feeding after total pancreatectomy. Malabsorption of both formulas was observed without enzyme supplementation. A marked improvement of fat and nitrogen absorption was obtained when pancreatic enzymes were added to both enteral diets. It is concluded that pancreatic enzymes should always be added to liquid diets in pancreatic insufficiency. No clear advantage is to be anticipated by the use of elemental as compared with polymeric diets.

Duodenal ulcer in chronic relapsing pancreatitis

Frequency of duodenal ulcer in patients with chronic pancreatitis is still controversial. This study aims to prospectively investigate the frequency of duodenal ulcer in a group of 190 patients (162 males and 28 females) affected by chronic relapsing pancreatitis admitted to our department between 1970 and 1979. 41 cases (21.5%) were endoscopically observed (22% of the males and 17.9% of the females; male:female ratio 1.2:1). Drinking habits, cigarette consumption, presence of pancreatic calcifications and surgery did not affect the frequency of duodenal ulcer. Exocrine pancreatic insufficiency, as fecal fat excretion higher than 7 g/day, seems to be linked with an increased frequency of duodenal ulcer (exact Fisher's test: p = 0.0586). Moreover, duodenal ulcer was present in about one third of the patients who afterwards died, but it was the cause of death in only 1 case. Even if a prospective control population is lacking, the male:female ratio of duodenal ulcer in chronic pancreatitis seems to be different from that observed in a comparable hospitalized group (1.2:1 vs. 2.4:1) and from that reported in literature in the general adult population.

Gastric emptying of solid meals in achalasic patients after successful pneumatic dilatation of the cardia

Gastric emptying of a solid meal was measured by ultrasound scanning in 16 achalasic patients following successful pneumatic dilatation of the lower esophageal sphincter. The data were compared with those of a control group of 15 healthy subjects. Fasting and maximal postcibal antral sections were very similar in the two groups. On the contrary, the time interval before maximal antral dilatation, and the time necessary for the emptying of half or of the whole meal were significantly longer in the achalasic patients than in the controls. Half of the achalasic patients had longer emptying times than the upper normal limit. The percentage of the meal retained in the antrum at each hourly interval was significantly higher in the achalasic group. The finding of a high prevalence of gastric emptying disturbances suggests that the functional derangement in achalasia is not limited to the esophagus.