PubMed Health⌕ Search

Biomedical subjects

W C Wu

Publications and source records attributed to W C Wu.

At least 127 records · Page 7Linked to original sources

Ambulatory 24-hour esophageal pH monitoring. Reproducibility and variability of pH parameters.

If 24-hour esophageal pH monitoring is to be a useful diagnostic tool, it must reliably discriminate gastroesophageal reflux patients despite daily variations in distal esophageal acid exposure. To address this issue, we studied 53 subjects (14 healthy normals, 14 esophagitis patients, and 25 patients with atypical symptoms) with two ambulatory pH tests performed within 10 days of each other. Intrasubject reproducibility of 12 pH parameters to discriminate the presence of abnormal acid reflux was determined. As a group, the parameters of percent time with pH less than 4 (total, upright, recumbent) were most reproducible (80%). Therefore, a subject was defined as having gastroesophageal reflux disease if at least one of these three values were abnormal. Intrasubject reproducibility for the diagnosis of reflux disease was 89% for the entire sample. Among subsets, the reproducibility was 93% for the normals and esophagitis patients and 84% for the atypical symptom patients. Total percent time with pH less than 4 was the single most discriminate pH parameter (85%) and nearly equaled that of the three combined parameters (89%). The intrasubject variability of this parameter was determined by the mean +/- 2 SD of the relative differences between the two test results for all 53 subjects. Total percent time with pH less than 4 may vary between tests by a factor of 3.2-fold or less (218% higher to 69% lower). We conclude: (1) ambulatory 24-hr esophageal monitoring is a reproducible test for the diagnosis of gastroesophageal reflux disease; and (2) the large intrastudy variability in 24-hr total acid exposure may limit this test's usefulness as a measurement of therapeutic improvement.

Adult↗

The symptom index: a clinically important parameter of ambulatory 24-hour esophageal pH monitoring.

Ambulatory 24-h esophageal pH monitoring is an accurate quantitative test of gastroesophageal reflux (GER). However, it does not answer the question: are the patients' symptoms due to GER? We developed a numerical scale to quantify the percent association between symptoms and pH less than 4--the symptom index (SI). In 100 consecutive patients with heartburn or chest pain, the SI for the chief complaint was either high (greater than 75%) or low (less than 25%) in 77% of cases. A similar bimodal distribution was seen when heartburn or chest pain symptoms were individually evaluated. There was a good association between high SI and the presence of GER (97.5%), as well as low SI and a normal 24-h pH study (81.1%). Endoscopy was normal in 89.5% of patients with low SI, but patients with high SI had esophagitis in only 69.7% of cases. The Bernstein test showed a poor association with the SI. Therefore, the SI gives clinically relevant information regarding the role of acid reflux and patient's symptoms. We believe this simple calculated index should be included in the analysis of 24-h esophageal pH studies.

Chest Pain↗

Comparison of potential cytoprotective action of sucralfate and cimetidine. Studies with experimental feline esophagitis.

The potential mucosal protective effects of a liquid sucralfate preparation and the histamine (H2)-antagonist cimetidine on acid-induced esophagitis were studied. Esophagitis was induced in adult cats using a constant infusion of 0.1 N hydrochloric acid at 1 ml/minute for 20 minutes. Mucosal lesions were evaluated by blinded investigators using both fiber-optic endoscopy and light microscopy. Histology was scored for basal cell hyperplasia, intraepithelial leukocytosis, and subepithelial leukocytosis. Liquid sucralfate given prior to acid infusion consistently prevented acid-induced lesions, demonstrated by quantitative histologic scoring. Although cimetidine did not show the same degree of protection as sucralfate, the results did show a trend towards a cytoprotective effect.

Animals↗

Sucralfate treatment of nonsteroidal anti-inflammatory drug-induced gastrointestinal symptoms and mucosal damage.

In a randomized, double-blind trial, sucralfate therapy, 1 g four times daily, was compared with placebo in 143 symptomatic patients to assess the treatment of gastrointestinal symptoms and gastric mucosal damage associated with nonsteroidal anti-inflammatory drugs (NSAIDs). All patients followed a fixed regimen of NSAIDs, were assigned to one of two groups based on the presence or absence of gastric erosions at baseline endoscopy, and were then assigned randomly to receive sucralfate or placebo for four weeks. Patients were then followed for up to six months while receiving open-label sucralfate 1 g twice daily to up to 1 g four times daily. After four weeks of double-blind therapy, patients taking either nonsalicylate NSAIDs or long half-life NSAIDs and who were treated with sucralfate experienced a significant reduction in both peptic symptom frequency and intensity (p less than 0.03) as compared with patients receiving placebo. Sucralfate-treated patients with baseline endoscopic lesions showed a significant reduction in lesion scores (p less than 0.005) at four weeks as compared with baseline, whereas no improvement was observed in gastric mucosal lesions of patients given placebo. Long-term sucralfate therapy resulted in continued improvement in gastrointestinal symptoms and gastric lesion scores in patients receiving all types of NSAIDs. The results indicate that sucralfate used in conjunction with NSAIDs may allow patients to continue therapy by relieving gastrointestinal symptoms and mucosal damage associated with NSAID therapy.

Aged↗

Esophageal manometry in 95 healthy adult volunteers. Variability of pressures with age and frequency of "abnormal" contractions.

UNLABELLED: Although esophageal manometry is widely used in clinical practice, the normal range of esophageal contraction parameters is poorly defined. Therefore, 95 healthy volunteers (mean age: 43 years; range 22-79 years) were studied with a low-compliance infusion system and 4.5-mm-diameter catheter. All subjects were given 10 wet swallows (5 cc H2O) and 38 subjects also were given 10 dry swallows. RESULTS: Amplitude, but not duration, was greater (P less than 0.05) after wet compared to dry swallows. Both distal mean contractile amplitude and duration of wet swallows significantly increased with age and peaked in the fifties. Double-peaked waves frequently occurred after both wet (11.3%) and dry (18.1%) swallows, but triple-peaked waves were rare (less than 1%). Nonperistaltic contractions were more common (P less than 0.001) after dry compared to wet swallows (18.1% vs 4.1%). This difference resulted from frequent simultaneous contractions after dry swallows (12.6% vs 0.4%). CONCLUSIONS: Distal esophageal contractile amplitude and duration after wet swallows increases with age. Triple-peaked waves and wet-swallow-induced simultaneous contractions should suggest an esophageal motility disorder. Double-peaked waves are a common variant of normal. Dry swallows have little use in the current evaluation of esophageal peristalsis.

Adult↗

Radiographic evaluation of esophagus immediately after pneumatic dilatation for achalasia.

Forty-one (98%) of 42 patients with achalasia of the esophagus had pneumatic dilatation performed successfully using the Brown-McHardy dilator. One to four dilatations (mean, 1.9) were done on each patient with inflation pressures of 8-15 psi (mean, 11.1 psi). Immediately after the procedure, all patients were examined radiographically by injection of contrast material into the lower esophagus through a nasoesophageal tube. Two immediate and two delayed perforations occurred. Six intramural hematomas were noted, five of which resolved spontaneously. The luminal diameter at the esophagogastric junction increased from a mean of 4.2 mm before dilatation to 7.5 mm following treatment. Four patients with previous Heller myotomy were dilated without complications. Perforation was more common in patients with a minimal change in the esophagogastric diameter. Thirty-five patients (85%) improved symptomatically within several days following pneumatic dilatation. Excluding patients with perforation, the postdilatation appearance of the lower esophagus poorly correlated with clinical response.

Adolescent↗

Cowden's disease: a case report and literature review.

Cowden's disease, or multiple hamartoma syndrome, is an uncommon condition with characteristic mucocutaneous lesions associated with abnormalities of the breast, thyroid, and gastrointestinal tract. We describe a 51-year-old man with hyperplastic polyposis of the entire alimentary tract as the most prominent feature of this disease. We also present a review of 85 cases of this entity as reported in the English medical literature, and summarize the pertinent findings.

Adenomatous Polyposis Coli↗

Esophageal radiography and manometry: correlation in 172 patients with dysphagia.

Radiographic and manometric examinations of the esophagus were correlated in 172 patients with dysphagia. Esophageal manometry was abnormal in 66 (38%), with diagnoses of nonspecific esophageal motor disorder (26), achalasia (19), nutcracker esophagus (12), diffuse esophageal spasm (seven), and scleroderma (two). Compared with manometry, radiographic sensitivities were 95% (18 of 19) for achalasia, 71% (five of seven) for diffuse esophageal spasm, and 46% (12 of 26) for nonspecific esophageal motor disorder. Nutcracker esophagus was not diagnosed specifically on the radiographic examination. Overall radiographic sensitivity was 56% (37 of 66) but increased to 89% by excluding nutcracker esophagus and nonspecific esophageal motor disorders. In 106 manometrically normal patients, radiographic specificity was 91% with 10 false-positive diagnoses of nonspecific motor disorder. We conclude that radiographic examination of the esophagus is useful in patients with dysphagia for evaluating functional esophageal abnormalities, although detection rates vary widely with the type of motor disorder.

Deglutition Disorders↗

Esophageal testing of patients with noncardiac chest pain or dysphagia. Results of three years' experience with 1161 patients.

Records from 910 patients referred to our clinical esophageal manometry laboratory for evaluation of noncardiac chest pain between January 1983 and December 1985 were reviewed and compared with records from 251 patients referred for dysphagia. Evaluation included baseline esophageal manometry, acid perfusion test, and edrophonium provocation. In the chest-pain group, 655 patients (72%) had normal esophageal motility and 255 (28%) had abnormal motility. Nutcracker esophagus was present in 48% of abnormal tracings, suggesting that it is a manometric marker for noncardiac chest pain. Of the total chest-pain group, 243 patients (27%) had their pain reproduced during provocative testing ("definite" esophageal pain); 192 patients (21%) had baseline manometric abnormalities but no pain during provocative testing ("probable" esophageal chest pain). The highest percentage of positive provocative responses (34%) occurred in patients with nutcracker esophagus on baseline manometry. Manometric abnormalities were statistically commoner (p less than 0.001) in patients with dysphagia, occurring in 53%. Achalasia (36%) and nonspecific esophageal motility disorders (38%) were the commonest abnormalities in this group, with nutcracker esophagus being infrequent (10%).

Acids↗

NSAID-induced gastric mucosal damage.

Gastric mucosal damage is a common side effect of nonsteroidal anti-inflammatory drugs (NSAIDs). These drugs may cause gastrointestinal symptoms, gastric erosions, peptic ulcers or upper gastrointestinal bleeding. Therefore, NSAIDs should be used cautiously in patients with a history of gastrointestinal lesions. Drugs that may be useful in preventing or treating NSAID-induced gastric mucosal injury are under intensive clinical investigation.

Adult↗

Clinical and genetic characteristics of upper gastrointestinal disease in rheumatoid arthritis.

Clinical and genetic studies were analyzed in 47 patients with rheumatoid arthritis (RA) who had upper gastrointestinal (GI) endoscopies. Fifty-three percent of patients with RA had peptic ulcers and/or erosions. Sixty percent of patients with ulcers and/or erosions had a history of peptic ulcer disease. Although a greater number of patients with ulcers and/or erosions was taking regular aspirin or indomethacin, comparable numbers of patients with abnormal and normal endoscopies were using nonsteroidal antiinflammatory drugs. Nineteen of the 25 patients (76%) with ulcers and/or erosions had type O blood. Patients with abnormal and normal endoscopies had similar frequencies of GI complaints and fecal blood loss. GI symptoms and occult fecal blood loss, therefore, are not prominent features of upper GI disease in RA. ABO screening may be helpful in determining which patients with RA are at risk for developing peptic ulcers and/or erosions.

ABO Blood-Group System↗

Pneumatic dilatation of the achalasic esophagus requiring the aid of an endoscope.

We describe a 65-yr-old man with achalasia, who had two previous Heller myotomies. He had a markedly dilated, tortuous esophagus, which defeated initial attempts at pneumatic dilatation. A method was improvised in which a Brown-McHardy dilator was attached by a string to a small caliber endoscope and both were successfully passed into the stomach. Pneumatic dilatation was then easily performed. Review of the literature and our experience with four patients suggests that pneumatic dilatation can be performed without substantial risk in patients after a failed Heller myotomy.

Aged↗

Relationship of radionuclide liquid bolus transport and esophageal manometry.

Using simultaneous esophageal manometry and radionuclide transit studies, we compared liquid bolus transport with the various parameters of esophageal contractions. Study subjects included seven normal individuals, six patients with the "nutcracker esophagus" (mean distal peristaltic amplitude greater than 180 mm Hg), and three patients with spastic motility disorders. Manometric studies were performed when the subjects were in the basal state and after intravenous administration of edrophonium and atropine. Simultaneous radionuclide studies were done with subjects in the supine position by swallows of 250 mu Ci technetium Tc 99m sulfur colloid in 10 ml water. We found that normal liquid bolus transport (less than 15 seconds) is primarily dependent on the presence of a peristaltic wave front throughout the esophagus. Above a threshold pressure of 30 mm Hg, liquid transport was not affected by amplitude (33 to 500 mm Hg) or duration (3 to 15 seconds) of esophageal contractions. Repetitive wave forms also gave normal transit times as long as the wave front was peristaltic in onset. There was a significant inverse correlation (-0.65; P less than 0.001) between liquid transit time and peristaltic velocity. Prolonged radionuclide transport (30 to less than 50 seconds) was observed only with nonperistaltic contractions and very low amplitude (15 to 30 mm Hg) peristaltic waves.

Atropine↗