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Biomedical subjects

Y K Chen

Publications and source records attributed to Y K Chen.

At least 73 records · Page 4Linked to original sources
PubMed1995

Torulopsis glabrata-infected pancreatic pseudocysts. Diagnosis and treatment.

Torulopsis glabrata, a fungus commensal with the human gastrointestinal tract, so far has not been recognized as a cause of pancreatic sepsis. We report the cases of two patients with pancreatic pseudocysts that became infected with T. glabrata. A 20-year-old woman 6 weeks postpartum had acute gallstone pancreatitis complicated by pseudocyst formation and pancreatic sepsis. Pseudocyst fluid obtained at cystogastrostomy showed a pure culture of T. glabrata. A 52-year-old man with multiple medical problems showed signs of an infected pseudocyst 9 days after he was hospitalized for alcoholic pancreatitis. Computed tomography (CT)-guided aspiration of the the pseudocyst fluid confirmed T.glabrata as the infecting organism. Neither patient had a history of endoscopic or surgical manipulation. Prolonged therapy with broad-spectrum antibiotics and parenteral hyperalimentation were implicated as risk factors, and other possible pathogenic mechanisms were considered. Both patients were treated successfully with a combination of percutaneous or surgical drainage and amphotericin B, which appears to be the most active drug in vitro. The efficacy of other antifungal agents is discussed. In the context of pancreatitis and/or pseudocysts, empiric therapy with broad-spectrum antibiotics should be minimized because it predisposes patients to superinfection by opportunistic pathogens.

Adult↗
PubMed1995

Hypertrophic pulmonary osteoarthropathy in nasopharyngeal carcinoma: an early sign of pulmonary metastasis.

The aims of this study were to determine the incidence of hypertrophic pulmonary osteoarthropathy (HPO) in nasopharyngeal carcinoma (NPC) and assess its clinical significance. Altogether, 407 NPC patients were reviewed retrospectively. HPO was identified by 99Tcm-methylene diphosphonate bone scans and related clinical and radiographic evidence. Pulmonary metastases, bony metastases and titre of anti-Epstein Barr virus (EBV) immunoglobulin were assessed in patients with and without HPO. The patients had a mean (+/- S.D.) age of 50.4 +/- 12.4 (range 17-73) years. HPO was found in 27 of the 407 (6.6%) NPC patients, among whom 13 (48%) had pulmonary metastases. HPO preceded lung metastases by 7-22 months (14.4 +/- 6 months) in 7 (52%) patients. Six patients had overt lung metastases at the time of the bone scan. No significant difference was found in anti-EBV immunoglobulins between the patients with or without HPO, nor in the incidence of bony metastases between these two groups of patients. HPO should be regarded as an early sign of pulmonary metastases.

Adolescent↗
PubMed1995

Immunohistochemical demonstration of epithelial glutathione S-transferase isoenzymes in normal, benign, premalignant and malignant human oral mucosa.

The expression and localization of glutathione S-transferase (GST) isoenzymes in the epithelium of normal oral mucosa (n = 9), overlying reactive fibrous hyperplasia (n = 9), and of potentially malignant [leukoplakia (n = 25), submucous fibrosis (n = 12), verrucous hyperplasia (n = 16)] and malignant [squamous cell carcinoma (n = 36), verrucous carcinoma (n = 13)] oral lesions were examined immunohistochemically using polyclonal antibodies raised against GST isoenzymes (alpha, mu and pi) with the standard avidin-biotin-peroxidase complex (ABC) method. GST alpha, mu and pi were almost completely absent in the epithelium of normal oral mucosa and overlying benign fibrous tissues. GST alpha staining was cytoplasmic and focally positive, while GST mu staining was similar to but weaker than that seen for GST alpha. GST pi showed both cytoplasmic and nuclear staining and was expressed in 60% of leukoplakias with mild dysplasia (n = 15), 80% of leukoplakias with moderate to severe dysplasia (n = 10). 75% of submucous fibrosis samples (n = 12), 75% of verrucous hyperplasias (n = 16), 77% of verrucous carcinomas (n = 13), 81% of well-differentiated squamous cell carcinomas (n = 26) and 70% of moderate- to poorly-differentiated squamous cell carcinomas (n = 10). In addition, GST pi expression was independent of the state of differentiation of oral cancers. Since GST pi was significantly over-expressed in the oral premalignant and malignant lesions, the kinetics of GST pi-positive cells and the value of GST pi as a tumor marker in oral carcinogenesis need further investigation.

Biomarkers, Tumor↗
PubMed1995

Gastroesophageal reflux disease in the elderly: more severe disease that requires aggressive therapy.

OBJECTIVE: To evaluate gastroesophageal reflux disease in the elderly (people > or = 60 yr). METHODS: Basal gastric acid secretion was prospectively determined in 228 consecutive patients with symptomatic gastroesophageal reflux disease who had upper gastrointestinal endoscopy and were diagnosed with either pyrosis alone (n = 98), erosive esophagitis (n = 87), or Barrett's esophagus (n = 43). RESULTS: Patients > or = 60 yr (n = 66) had significantly more esophageal mucosal disease (erosive esophagitis, Barrett's esophagus) than patients < 60 yr (n = 162)--81% versus 47% (p = 0.000002, Fisher's exact test). Furthermore, 87% of patients > or = 70 yr had esophageal mucosal disease. For each decade from < 30 yr to > or = 70 yr, there was a significant increase in esophageal mucosal disease (p = 0.002; chi 2 test, 23.96); however, there were no significant differences in severity of pyrosis symptoms or in mean basal acid output for each decade. When 146 of the 228 patients with gastroesophageal reflux disease were given enough ranitidine (mean, 630 mg/d; range, 300-3000 mg/d) for the relief of all pyrosis symptoms and healing of all esophageal mucosal disease, there were no significant differences in ranitidine therapy between each decade. CONCLUSIONS: Elderly patients with pyrosis symptoms severe enough to require upper gastrointestinal endoscopy have gastroesophageal reflux disease with more esophageal mucosal disease (erosive esophagitis, Barrett's esophagus) than patients < 60 yr, and like younger patients, may require markedly increased doses of ranitidine as large as 2400 mg/d for effective therapy.

Adult↗
PubMed1995

Clinical outcome of post-ERCP pancreatitis: relationship to history of previous pancreatitis.

OBJECTIVE: The aim of this prospective study was to evaluate the relationship between clinical outcome of post-ERCP pancreatitis and history of previous pancreatitis. METHODS: Fifty patients (3.5%) developed procedure-related pancreatitis during the study period. Twenty-one patients had a history of previous pancreatitis (group I), and 29 patients had no history of previous pancreatitis (group II). There were no significant differences between the two groups with regard to age, gender, pancreatic duct injection, acinarization, or type of ERCP procedure. Grading of clinical severity was based on length of hospitalization, presence of pancreatic complications, and need for intervention: mild 28%, moderate 54%, and severe 18%. Four patients (8.0%) had pancreatic complications, but only one patient required surgery. There were no associated mortalities. RESULTS: Patients in group I had a shorter median hospital stay and were less likely to develop severe pancreatitis than patients in group II: 4.0 versus 7.0 days, p = 0.001 and 4.8 versus 27.6%, p = 0.038, respectively. CONCLUSIONS: Intralobular and/or periductal fibrosis secondary to prior pancreatitis may limit the degree of ERCP-induced pancreatic acinar damage.

Adolescent↗
PubMed1995

Colocare self-test versus Hemoccult II Sensa for fecal occult blood testing.

OBJECTIVES: To compare the efficacy of ColoCARE Self-Test pads against Hemooccult II SENSA, a traditional guaiac-based card test, in the screening for colorectal neoplasia. METHODS: Prospective crossover analysis of 102 high-risk patients for screening of colorectal neoplasia with fecal occult blood testing, using ColoCARE Self-Test pads and Hemoccult II SENSA cards. RESULTS: Sixty-eight of the 102 patients (67%) had colorectal lesions diagnosed at colonoscopy. Of this group, 55 patients (81%) had either a polyp or cancer diagnosed at colonoscopy, with 13 of these 55 patients having polyps > or = 1 cm. ColoCARE detected 21% of all lesions, compared with 72% for Hemoccult II SENSA. ColoCARE detected only 16% of cases involving either a cancer or a polyp, and 24% of cases involving either a cancer or polyp > or = 1 cm in size. This compares with 75% and 95%, respectively, for Hemoccult II SENSA. Significantly more patients preferred ColoCARE (84%) to Hemoccult II SENSA (5%) (p < 0.00001), and patients found it easier to use ColoCARE (p < 0.01). However, 33% of patients did not feel comfortable interpreting the ColoCARE results, and 29% found it difficult to interpret the color change. CONCLUSION: These results indicate that patients may prefer the simplicity and convenience of ColoCARE; however, the test is not sensitive for the detection of colorectal neoplasia. Furthermore, patients do not feel comfortable interpreting ColoCARE results and prefer to have fecal occult blood testing interpreted by medical personnel.

Adult↗
PubMed1994

Giant duodenal ulcer. Evaluation of basal acid output, nonsteroidal antiinflammatory drug use, and ulcer complications.

Patients with giant duodenal ulcer (> 2 cm) have more ulcer complications (ie, bleeding) than patients with duodenal ulcer in the standard range (0.5-1.5 cm). To evaluate possible differences between patients with giant duodenal ulcer and those with duodenal ulcer in the standard range, we determined basal acid outputs by nasogastric suction, percentage of patients with daily nonsteroidal antiinflammatory drug (NSAID) use, and percentage of ulcer complications in 184 patients with endoscopically documented active duodenal ulcer. Seventeen patients had giant duodenal ulcer, and 167 patients had duodenal ulcer in the standard range. The mean basal acid outputs for the 17 patients with giant duodenal ulcer was 7.9 meq/hr (range 0.0-27.8 meq/hr) and for the 167 patients with duodenal ulcer in the standard range was 9.0 meq/hr (range 0.0-49.1 meq/hr), which were not significantly different. There was a significant difference in the percentages of ulcer complications between the 17 patients with giant duodenal ulcer and the 167 patients with duodenal ulcer in the standard range: 65% compared to 25% (P = 0.001), and in the percentages of patients with regular daily NSAID use, during the one month preceding the upper gastrointestinal endoscopy: 53% compared to 8% (P = 0.00001). However, a significant association between NSAID use and duodenal ulcer complication was not apparent. These results suggest that the development of giant duodenal ulcer and the significant increase in complications associated with giant duodenal ulcer are not attributable to increased basal acid output, however, they may be attributable to increased NSAID use.

Adolescent↗
PubMed1994

Reappraisal of scrotal scintigraphy in evaluation of varicocoeles.

Varicocoeles could be classified into stop-type and shunt-type. In stop-type varicocoeles, only the internal spermatic (testicular) vein is dilated and needs to be ligated. In shunt-type, both internal spermatic vein and external spermatic (cremasteric) vein are dilated due to incompetence of the cremasteric system and both venous systems require ligation. Two-phase (flow and static) scrotal scintigraphy was performed on 92 patients preoperatively. Forty-three patients in whom the testicular and cremasteric veins could be verified during operation were included in this study. All 43 patients had unilateral varicocoeles and had abnormal blood pooling in the affected spermatic cord and hemiscrotum. In the blood flow study, 22 of 27 shunt-type varicocoeles had abnormal flow in the spermatic cord whereas only one out of 16 stop-type varicocoeles had increased blood flow. No difference in the results of semen analysis was found between the two groups of patients. Two-phase scrotal scintigraphy provides a noninvasive evaluation of shunting of the retrograde venous flow from the internal spermatic to the external spermatic vein. Understanding this pathophysiological change would be of benefit in the decision making about a surgical approach to varicocoeles.

Humans↗
PubMed1994

Hemoptysis secondary to bronchial varices associated with alcoholic liver cirrhosis and portal hypertension.

End-stage liver disease is associated with systemic changes involving many organs. Several pulmonary, tracheal, bronchial, and pleural abnormalities have been described. In this report we describe the first case of hemoptysis secondary to bronchial and lower tracheal varices in a patient with end-stage alcoholic liver disease and portal hypertension, and explore the relationship between tracheobronchial varices and portal hypertension.

Bronchi↗
PubMed1994

Endoscopic sphincterotomy-induced pancreatitis: increased risk associated with nondilated bile ducts and sphincter of Oddi dysfunction.

OBJECTIVE: to evaluate the relationship between common bile duct diameter and the risk of sphincterotomy-induced pancreatitis. METHODS: Two hundred and ten consecutive patients were prospectively investigated. Patients were divided into three groups according to the indication for sphincterotomy: Group I had common bile duct stones (n = 108), group II had sphincter of Oddi dysfunction (n = 48), and group III had sphincterotomy for other indications (n = 54) (i.e., stent, dilation). RESULTS: There were 62 males and 148 females with a mean age of 60 yr (range 15-93 yr). Eleven of the 210 patients (5.2%) developed pancreatitis. Other sphincterotomy-induced complications were bleeding (n = 2), cholangitis (n = 2), retroperitoneal duodenal perforation (n = 1), and bile duct leakage (n = 1). The percentages of pancreatitis in groups I (3.7%), II (12.5%), and III (1.9%) were significantly different (p = 0.03). Patients with nondilated common bile ducts (< or = 10 mm) had more pancreatitis than patients with dilated common bile ducts (8.8% vs. 2.8%), but the difference was not significant (p = 0.07). However, when group III was excluded from the analysis, there was a significant difference in the percentage of pancreatitis between the patients with nondilated bile ducts and those patients with dilated bile ducts (13.1% vs. 2.2%, respectively; p < 0.01). Analysis for trend did not show a significant inverse relationship between bile duct diameter and the rate of sphincterotomy-induced pancreatitis. However, for all complications combined, the inverse relationship between bile duct diameter and rate of sphincterotomy-induced complications was significant: < or = 5 mm (23.1%), > 5-10 mm (13.8%), > 10-15 mm (3.2%), > 15 mm (2.4%) (p = 0.002). CONCLUSIONS: Endoscopic sphincterotomy is more hazardous in patients with nondilated bile ducts and sphincter of Oddi dysfunction. Further studies are needed to determine whether pancreatic stenting reduces the risk of sphincterotomy-induced pancreatitis in those clinical settings.

Common Bile Duct↗
PubMed1994

Age does not affect basal gastric acid secretion in normal subjects or in patients with acid-peptic disease.

OBJECTIVES: To determine whether basal acid output was affected by patient age. METHODS: Basal acid output determined by nasogastric suction was prospectively evaluated in normal subjects (n = 65) and patients with gastroesophageal reflux disease (n = 228), gastric ulcer (n = 81), duodenal ulcer (n = 184), and nonulcer dyspepsia (n = 105). RESULTS: There was no correlation between basal acid output and age for the normal subjects and the patients with gastroesophageal reflux disease, gastric ulcer, duodenal ulcer, and nonulcer dyspepsia. However, there was a significant inverse correlation between age and basal acid output for the 33 male patients with gastric ulcer (r = -0.41, p < 0.05) and the 130 male patients with duodenal ulcer (r = -0.18, p = 0.05). Furthermore, mean basal acid outputs were significantly higher for male patients than for female patients with gastroesophageal reflux disease (p < 0.001), gastric ulcer (p < 0.05), and duodenal ulcer (p < 0.001). Mean basal acid output for the 184 patients with duodenal ulcer was significantly higher than the mean basal acid output for the 228 patients with gastroesophageal reflux disease (p < 0.001), and both were significantly higher than mean basal acid outputs for the normal subjects and the patients with gastric ulcer and nonulcer dyspepsia (p < 0.0005). CONCLUSIONS: Basal acid output can vary with gender and acid-peptic disease process; however, basal acid output does not vary with regard to age of subject.

Adult↗
PubMed1993

Free and conjugated catecholamines and serotonin in canine thoracic duct lymph: effects of feeding.

The source and fate of sulfoconjugated catecholamines present in plasma are not known. Sulfated norepinephrine has been shown to overflow together with free norepinephrine from a typical peripheral neuroeffector junction. Some released free norepinephrine is removed via the lymphatic system, but it is not known whether sulfated catecholamines are removed similarly. Serotonin, another biogenic amine, is released from the enterochromaffin cells into portal blood. The aims of the present study were to determine whether conjugated catecholamines and serotonin could be detected in thoracic duct lymph of dogs and to compare concentrations in lymph with those in samples of portal blood collected before and after the dogs were fed. A method is described for the extraction and purification of free and conjugated catecholamines and serotonin from lymph. In lymph and in plasma, there were similar concentrations of free (0.2-0.4 ng/ml) and conjugated (0.1-0.2 ng/ml) norepinephrine and of conjugated dopamine (0.2-1.0 ng/ml). The concentrations of free serotonin were much lower in lymph (0.1-0.2 ng/ml) than in portal blood (100-200 ng/ml). Small amounts of conjugated serotonin (0.1-0.4 ng/ml) were detected in lymph but were not detected in plasma. Feeding caused increases in concentration of conjugated dopamine in lymph and in plasma and small increases in the output of free norepinephrine and free and conjugated serotonin in lymph.

Amines↗
PubMed1993

Dieulafoy-like lesion of the rectum presenting with exsanguinating hemorrhage: successful endoscopic sclerotherapy.

The classic Dieulafoy lesion is a minute gastric mucosal defect that bleeds massively from an exposed artery. Similar lesions have been identified in the small intestine, colon, and rectum. In this report, we describe a patient who presented with an exsanguinating hemorrhage from a small rectal ulcer with a visible vessel. Control of the bleeding was achieved with endoscopic sclerotherapy using absolute alcohol and 1.5% sodium tetradocyl sulfate, with eventual complete healing of the site.

Adult↗
PubMed1993

Is there a role for upper gastrointestinal endoscopy in the evaluation of patients with occult blood-positive stool and negative colonoscopy?

OBJECTIVE: To determine the role of upper gastrointestinal endoscopy in the clinical investigation of patients with occult blood-positive and negative colonoscopy. METHODS: This is a retrospective study of 211 consecutive patients who were investigated by upper gastrointestinal endoscopy for occult blood-positive stool and negative colonoscopy. Patients were categorized into four groups: asymptomatic (n = 117), symptomatic (n = 37), severe anemia (hemoglobin < 10 g/dl) (n = 33), and incomplete (CBC not obtained or insufficient documentation regarding the presence or absence of symptoms) (n = 24). RESULTS: Eighty-eight of the 211 patients (42%) had abnormal upper gastrointestinal endoscopic findings: 43% of the "asymptomatic" group, 35% of the "symptomatic" group, 45% of the "severe anemia" group, and 42% of the "incomplete" group. The number of patients with abnormal upper gastrointestinal findings increased with age (p = 0.0002). Furthermore, there was a significant difference in upper gastrointestinal lesions between the patients who were 60 yr of age or older, and the patients less than 60 yr of age: 51% compared to 22% (p = 0.00003). All upper gastrointestinal endoscopic findings were benign, with 53 of the 88 patients (60%) having erosive gastritis. However, only 25 of those 88 patients (28%) had a lesion for which a specific treatment was available. CONCLUSIONS: Upper gastrointestinal endoscopy in patients with occult blood-positive stool and negative colonoscopy has a very low yield for significant lesions, not only from a therapeutic standpoint, but also for detection of malignant lesions. Prospective studies are needed to determine which specific groups of patients deserve further investigation.

Aged↗