Use of an ammonia electrode for rapid quantification of Helicobacter pylori urease: its use in the endoscopy room and in the assessment of urease inhibition by bismuth subsalicylate.

The use of an ammonia electrode to quantify ammonia liberated by urease from Helicobacter pylori was assessed in an in vitro study. It was found to be highly sensitive (down to 0.7 ppm NH3) and highly reproducible (coefficient of variation 6.0%). Inhibition of urease by bismuth subsalicylate was evaluated as urease testing is often used to assess clearance of H. pylori in patients treated with bismuth. Concentrations of bismuth subsalicylate up to 5 mg/ml had no inhibitory effect but bismuth subsalicylate at 50 mg/ml resulted in 21% inhibition of the urease activity of an ultrasonicated H. pylori suspension. As a preliminary study, the ammonia electrode was assessed in the endoscopy room in comparison with conventional techniques for H. pylori diagnosis. Antral biopsies from 39 patients attending for routine diagnostic endoscopy were subjected to culture, histology, detection of urease activity with a commercially available slide test (CLO) and with the ammonia electrode to detect ammonia liberated from samples placed in urea solution. 21 patients were positive after 1 h with the ammonia electrode, compared to only 17 with the commercially available slide test. 20 were positive on histology and 19 by culture. All samples positive with the ammonia electrode were either positive by culture or by histology. The ammonia electrode offers a quick, sensitive, quantitative and cheap method for the detection and quantification of H. pylori.     

Immediate and six-month results of the profile of the Amplatzer septal occluder as assessed by transesophageal echocardiography

Catheter closure of secundum atrial septal defect (ASD) using the Amplatzer septal occluder (ASO) is a potential alternative for open surgical repair. However, the large profile of the device obtained immediately after closure continues to raise some concerns regarding its long-term safety. To evaluate the changes in the profile of the device after being deployed, transesophageal echocardiography was performed in 70 patients (17 men and 53 women) who underwent catheter closure of ASDs immediately after and at 6-month follow-up. The median age at closure was 16 years (range 1.9 to 75) and the median size of the ASD as assessed by transesophageal echocardiography was 14 mm (range 3 to 25). The thickness (profile) of the device was assessed in the 4-chamber, short- and long-axis views of the interatrial septum, and measured at its middle and at the junction of the waist with the disc at its 2 ends. Seventy-three devices were deployed in the 70 patients. The median size of the device was 19 mm (range 8 to 34). Complete closure was achieved in 81.4% and 91.4% immediately after and at 6-months follow-up, respectively. The thickness of the device at its middle decreased from 12.2 +/- 4.3, 12.2 +/- 3.7, and 12.5 +/- 4.3 mm in the 4-chamber, short- and long-axis views to 6.5 +/- 2.0, 6.3 +/- 1.9, and 6.5 +/- 2.2 mm, respectively. The thickness of the device at its superior, inferior, anterior, and posterior edges also decreased by 41.8% +/- 14.0% to 43.7% +/- 9.8%. The changes in the thickness were related to device size. Larger devices were thicker after being deployed. We conclude that the thickness of the ASO decreases by 42% to 48% within 6 months after deployment, resulting in a lower profile.     

Allescheria boydii infections in the immunosuppressed host.

Allescheria boydii, a true fungus frequently isolated from soil, is best known as a causative agent of maduromycosis of the foot. In our report we describe two patients under treatment for acute leukemia who died from rapidly progressive A. boydii infections. One patient had signs of central nervous system infection and was found at autopsy to have had a large brain abscess. The second patient had a cavitary necrotizing pneumonia with thoracic inlet obstruction (Pancoast's syndrome) and failed to show improvement despite treatment with amphotericin B. The clinical spectrum of allescheriasis is reviewed with particular emphasis on its role as a pathogen in the compromised host. Since A. boydii may resemble other fungi morphologically in tissue sections and may produce infections clinically similar to other mycoses, culture of the organism is required for definitive diagnosis. Based on recently reported in vitro susceptibility studies, miconazole may have a future role in the therapy of A. boydii infections which are resistant to presently available antifungal agents.     

International comparison of mortality from inflammatory bowel disease in the Latin-speaking countries Venezuela, Italy, and France

Mortality data for ulcerative colitis, Crohn's disease, and unspecified inflammatory bowel disease were examined for the countries Venezuela, Italy, and France during the decade 1969-1978. These figures were compared with similar data from England and Wales obtained from 1965 to 1975. In Italy and France deaths from Crohn's disease and ulcerative colitis were low and showed little change during the period of observation. Figures for inflammatory bowel disease from Venezuela were high and appeared to show a marked fall which may simply reflect a change in diagnostic criteria.