Discrete event simulation of patient admissions to a neurovascular unit.

Evidence exists that clinical outcomes improve for stroke patients admitted to specialized Stroke Units. The Toronto Western Hospital created a Neurovascular Unit (NVU) using beds from general internal medicine, Neurology and Neurosurgery to care for patients with stroke and acute neurovascular conditions. Using patient-level data for NVU-eligible patients, a discrete event simulation was created to study changes in patient flow and length of stay pre- and post-NVU implementation. Varying patient volumes and resources were tested to determine the ideal number of beds under various conditions. In the first year of operation, the NVU admitted 507 patients, over 66% of NVU-eligible patient volumes. With the introduction of the NVU, length of stay decreased by around 8%. Scenario testing showed that the current level of 20 beds is sufficient for accommodating the current demand and would continue to be sufficient with an increase in demand of up to 20%.

Clinical experience of esophageal ulcers and esophagitis in AIDS patients.

In Taiwan, numbers of patients with the acquired immunodeficiency syndrome (AIDS) have been increasing in recent years. We present esophageal disease of different causes in 5(16%) heterosexual men among 31 AIDS patients over a 5-year period. Major symptoms included mild dysphagia in 4 (80%) patients and odynophagia in 3 (60%) patients. The duration of symptoms varied from 3 days to 6 months. The symptoms occurred before the diagnosis of AIDS in 3 patients. At esophagogastroduodenoscopy (endoscopy), all 5 patients had esophagitis and/or esophageal ulcers proved by histopathologic evaluation. Four had Candida esophagitis, 3 had cytomegalovirus esophagitis/ulcers and 2 had idiopathic esophageal ulcerations (IEU). Three patients had different esophagitis/ulcers at the same time or during follow-up. The median CD4 lymphocyte count at the time of diagnosis of esophageal disease was 12.2 cells/mm3 (range, 3 to 35 cells/mm3). The endoscopic pictures of the different causes of esophagitis/ ulcers lack uniformity in number, size and appearance. These observations make a conclusion that all AIDS patients with an esophageal disease should undergo endoscopy with biopsy to obtain a definitive diagnosis.

Polymerase chain reaction diagnosis of Helicobacter pylori in gastroduodenal diseases: comparison with culture and histopathological examinations.

Helicobacter pylori has been associated with a variety of upper gastrointestinal diseases. Histopathological examination and culture are considered to be the more specific tests in the diagnosis of H. pylori infection. In the present study, we evaluated the efficiency of a polymerase chain reaction (PCR) assay of the H. pylori urease A gene as a procedure in the diagnosis of gastric H. pylori infection in various gastroduodenal diseases. Biopsy specimens were obtained from the antral mucosa of 83 patients during endoscopic examination and were submitted to three tests for the detection of H. pylori infection. The detection rates of H. pylori using PCR, histopathological examination and culture were 84, 77 and 63%, respectively. When the infection was defined, by the agreement of culture and histopathological examination or by positive culture, the PCR assay had a sensitivity of 98.1% and a specificity of 84.6%. When the infection was defined by a positive result of either two of the three tests or by positive culture, the PCR assay had a sensitivity of 98.6% and a specificity of 85.7%. We conclude that the PCR assay is a valuable test for the diagnosis of H. pylori infection in gastroduodenal diseases.

Congestive gastropathy in cirrhotic patients: correlation between endoscopic and histological findings.

Congestive gastropathy is a common cause of gastrointestinal bleeding in cirrhotic patients. Forty-six patients with cirrhosis of the liver and 225 control subjects matched in age and sex without cirrhosis of the liver entered the study. We studied the prevalence of congestive gastropathy in cirrhotic patients, and the relationship between endoscopic and histological findings. Congestive gastropathy seen endoscopically was found to be more common in the cirrhotic group than in the control (85% vs. 5%, P < 0.05). The sensitivity, specificity and positive predictive value were 85%, 95% and 76%, respectively. The presence of endoscopic congestive gastropathy was correlated with the severity of liver disease (P < 0.05), but not to the etiology of cirrhosis and the size of esophageal varices with or without red color sign. Endoscopic congestive gastropathy showed no correlation with the histological features including gastritis, interstitial edema, vessel ectasia/congestion and hemosiderin in endoscopic biopsy specimens. In conclusion, congestive gastropathy is a common finding in cirrhotic patients. Its appearance is closely correlated with the severity of liver disease. There is no good correlation between endoscopic congestive gastropathy and mucosal histology.

[Campylobacter pyloridis in active chronic gastritis and peptic ulcer].

From Oct. 1986 to Jan. 1987, a total of 74 patients presenting for endoscopy were studied. These included 30 cases of active chronic gastritis and 44 cases of peptic ulcer. Biopsy specimens were taken during the endoscopy and sent to the laboratory for Campylobacter pyloridis culture within 2 hours. The culture was done by inoculated with chocolate agar, Brucella agar and 0.2% urea broth for urease activity. Results showed that, 53% (16/32) of active chronic gastritis, 77% (10/13) of gastric ulcer and 84% (26/31) of duodenal ulcer were positive for Campylobacter pyloridis. The specificity and sensitivity of urease positive rate are 64% and 90% respectively. It is higher as compared with bacteria culture. In addition, we found that 10 days would be needed for the routine culture and identification of this organism. But it took only 30 minutes to 6 hours for urease activity test. Therefore, we suggested that urease activity test could be a rapid diagnostic method for detecting Campylobacter pyloridis.