Winfried A. Voderholzer

Symptoms in chronic constipation

OBJECTIVES: This study was designed to evaluate whether detailed symptom analysis would help to identify pathophysiologic subgroups in chronic constipation. METHODS: In 190 patients with chronic constipation (age, 53 (range, 18–88) years; 85 percent of whom were women), symptom evaluation, transit time measurement (radiopaque markers), and functional rectoanal evaluation (proctoscopy, anorectal manometry, defecography) were performed. Patients were classified on the basis of objective data from all tests in four different groups (“disordered defecation,” “slow gastrointestinal transit,” “disordered defecation combined with slow-transit stool,” and “no pathologic finding”). RESULTS: In 59 percent of patients, disordered defecation was found, and 27 percent had slow-transit stool. In 6 percent of patients, a combination of both was found; in only 8 percent of patients, there were no pathologic findings. Straining was reported by the vast majority in all groups (82–94 percent). Infrequent bowel movements and abdominal bloating were more common in slow-transit stool (87 and 82 percentvs. 69 and 55 percent, respectively; bothP<0.01). Feeling of incomplete evacuation was more common in disordered defecation (84vs. 46 percent;P<0.0001). However, specificity of these symptoms was discouraging (for slow-transit stool: infrequent bowel movements had a sensitivity of 87 percent and a specificity of 32 percent and abdominal bloating had a sensitivity of 82 percent and specificity of 45 percent; for disordered defecation: feeling of incomplete evacuation had a sensitivity of 84 percent and a specificity of 54 percent). Only the sense of obstruction and digital maneuvers were acceptably specific (79 and 85 percent, respectively) for disordered defecation, but sensitivity was low. CONCLUSIONS: Definition of chronic constipation by infrequent bowel movements alone is of little value; the symptom “necessity to strain” is much better suited (94 percent sensitivity). Specificity of infrequent bowel movements for slow-transit stool was discouraging. Sense of obstruction and digital manipulation for evacuation are relatively specific for disordered defecation but insensitive. Therefore, symptoms of chronically constipated patients are not well suited to differentiate between the pathophysiologic subgroups suffering chronic constipation.

What is behind dyspepsia

The first aim of the present study was to determine the cause of dyspepsia after negative conventional diagnostic work-up. In such patients, an extended diagnostic work-up was performed including esophageal pH monitoring and manometry, gastric and hepatobiliary scintigraphy, and lactose tolerance test. In 88 of 220 dyspeptic patients (mean age 49 years, range 17–87; 114 women) presenting to our gastroenterological outpatient department, a cause for dyspepsia was found by conventional work-up. Thirty-one of the remaining patients did not enter extended work-up, because of minor symptoms. In 47 of 101 patients entering extended work-up, a diagnosis was established (21 endoscopynegative gastroesophageal reflux disease, 11 gastric stasis, 6 biliary dyskinesia, and 5 lactase deficiency among them). A second aim of the study was to determine whether clusters of symptoms such as “gastroesophageal reflux-like”, “dysmotility-like”, and “dyspepsia of unknown origin” reliably predict the groups of diseases suggested by these terms. This was not the case. In conclusion, in 40% of dyspeptic patients, a conventional diagnostic work-up led to a diagnosis that explained a patients symptoms. After a negative conventional diagnostic work-up, an extended diagnostic work-up with functional tests yielded a possible explanation for their symptoms in 47% of patients. In such patients symptomatology was of little help for predicting the diagnosis.

Behavioral modification of colonic function

We challenged the two hypotheses: first, that defecation can be suppressed for an extended time, and second, if so, that this has an effect on upper colonic motility. Thus we studied 12 male volunteers with conditions of identical nutrition and patterns of physical activity over a two-week period, where one week with normal defecation and one week with voluntary prolonged suppression of defecation followed each other in randomized order. Frequencies of defecation, stool weights, total and segmentai colonic transit times (using radiopaque markers) were compared. Frequency of defecations and stool weights were lower during suppressed defecation [8.9±0.66 vs 3.7±0.41 (mean±SE) bowel movements per week, P=0.003, and 1.30±0.09 vs 0.98±0.13 kg/week, P=0.01]. Total transit times were increased from 28.8±4.4 to 53.1±4.3 hr, P=0.004. Segmental transit times were increased in the rectosigmoid (from 8.83±3.6 to 32.1±5.6 hr, P=0.04) and right hemicolon (from 14.5±0.9 hr to 19.7±1.5 hr, P=0.02) by suppression of defecation. We conclude that defecation habits may induce changes in colonic function such as those seen in constipation and that functional anorectal outlet obstruction may, probably by reflex mediation, affect the right colon.

Decreased substance P levels in rectal biopsies from patients with slow transit constipation

Objective: Previous studies in patients with chronic constipation found abnormalities in the nervous tissue of the large intestine, predominantly in the muscularis externa. Since there is evidence that the nervous system of mucosa and submucosa is also involved in the control of colonic motility we investigated the contents of vasoactive intestinal polypeptide (VIP), somatostatin and substance P in rectal biopsies of patients with slow colonic transit constipation. Design and methods: Twenty-two patients (17 females, 5 males) with chronic slow transit constipation (oro-anal transit with radio-opaque markers on high fibre diet > 70 h) and long-term use of laxatives, and 20 controls (12 females, 8 males) with no history of constipation, were included in this study. Large rectal biopsy specimens including the submucosa were obtained from 5 cm above the dentate line and frozen in liquid nitrogen. After microdissection of the biopsies into mucosa and submucosa the neuropeptides were extracted by boiling and homogenizing the tissue in acetic acid and determined using validated radioimmunoassays. Results: Patients with slow transit constipation showed, compared to healthy controls, significantly lower levels of the excitatory neurotransmitter substance P in the mucosa and submucosa of rectal biopsies. There was no difference between the two groups concerning the levels of the inhibitory neurotransmitters, VIP and somatostatin. Conclusion: Slow transit constipation is associated with abnormalities of the substance P content of the enteric nervous system of mucosa and submucosa. This seems not to be related to chronic laxative use, since anthranoids cause a reduction in the levels of inhibitory neurotransmitters (VIP, somatostatin), but not of substance P, in the rat colon. European Journal of Gastroenterology & Hepatology 1996, 8:1207–1211

Mean acidity or percentage reflux time in oesophageal pH-monitoring

Objectives: The reflux parameter mean acidity, which is independent of any pH threshold, was compared with the established parameter percentage of time when the pH is less than 4 with respect to the discriminatory diagnostic accuracy in gastro-oesophageal reflux disease and the evaluation of drug effects. Methods: Normal values, sensitivity and specificity of pH-monitoring were calculated using receiver operating characteristic (ROC) analysis in 35 reflux patients and 19 healthy controls. In addition, 32 patients were studied twice, without medication (baseline) and with either antacids (five patients), ranitidine (13 patients) or omeprazole (14 patients). Results: The percentage reflux time was superior to the mean acidity in the diagnosis of gastro-oesophageal reflux disease (maximal sensitivity/specificity was 91/95% compared with 83, 84%). Antacids did not reduce the percentage reflux time or the mean acidity. Ranitidine only reduced the percentage reflux time for the supine body position from 7.7 (0.2–46.4) to 0.72% (0.0–14.9, P < 0.05). Omeprazole reduced all reflux parameters; the percentage reflux time for the upright body position from 9.6 (5.0–52.3) to 1.6% (0.0–22.5, P < 0.01) and for the supine position from 4.9 (0.0–23.7) to 0.0% (0.0–48.5, P < 0.050, and the mean acidity from 0.84 (0.02–76.0) to 0.01 mmol/l (0.0–0.71, P < 0.001). Mean acidity described the effect of omeprazole significantly better than percentage reflux time. Conclusions: In the diagnosis of gastro-oesophageal reflux disease, percentage reflux time is superior to mean acidity. Mean acidity, however, seems to be the better parameter to describe the reduction in acid gastro-oesophageal reflux afforded by potent antisecretory drugs.

The influence of a manometric tube on radionuclide transit of liquid and semi-solid boluses

Abstract Twenty‐nine patients referred for oesophageal diagnostic work up prospectively divided into patients with normal (‘controls’) and abnormal motility on the basis of manometric findings underwent oesophageal scintigraphy with and without simultaneous manometry. All patients with abnormal peristalsis had a mean pressure amplitude of less than 30 mmHg andlor simultaneous contractions in the proximal andlor distal half of the oesophagus. For manometry a low compliance perfusion system was used (external diameter of the manometric tube 0.5 cm). Radionuclide oesophageal emptying (%) was measured 12 sec after the beginning of each swallow. Values of >8O% were considered normal. Oesophageal emptying for liquid and semi‐solid test‐boluses during manometry was compared t o the corresponding values obtained without the manometric tube in place. Oesophageal emptying was reduced during studies with the manometric tube in situ in controls from 97.6 ± 1.2% to 85.9 ± 5.3%, P = 0.018 forliquid boluses, and from 95.3 ± 1.2% to 84.4 ± 4.3%, P = 0.01 for semi‐solid boluses. A trend was also seen in patients with abnormal contractility which was not statistically significant (65.6 ± 9.0% vs 56.6 ± 8.5% P = 0.1, 62.4 ± 9.1% vs 56.7 ± 7.6%, p=0.4). Three controls duringliquid studies and four controls during semi‐solid studies were falsely classified as pathological by scintigraphy with the tube in situ whereas only one patient with abnormal contractility was classified normal in each of the liquid and semi‐solid studies. In conclusion, subjects with normal contractility patterns may show pathological emptying in radionuclide studies if simultaneous manometry is performed. Patients who have reduced oesophageal emptying may be less often falsely classified as normal.