RESUMO
In this study, we evaluated a simplified rapid 14C-urea breath test for the diagnosis of Helicobacter pylori. Fasting patients undergoing initial assessment for H. pylori drank 5 microCi of 14C-urea in 20 ml of water. Breath was collected at intervals for 30 min. Samples were counted in a beta-counter, and the results were expressed as counts per minute (cpm). In the same week, patients underwent endoscopy, and a blinded investigator examined biopsy samples of gastric mucosa by culture and histology for H. pylori. There were 49 H. pylori-negative (HP-) and 104 H. pylori-positive (HP+) patients in the study. HP+ patients expired a mean of 4398 cpm (SD 2468) per mmol CO2 in a sample taken 20 min after ingestion of the isotope. In contrast, HP--patients expired only 340 cpm (SD 196). If the mean +3 SD of HP- patients was used as a cutoff value, the 20-minute sample gave a sensitivity of 97% and a specificity of 100% for detecting H. pylori. The radiation exposure from this test is less than 1% of that received from an upper gastrointestinal series, and the short collection time makes it both convenient and cost effective.
Assuntos
Testes Respiratórios/métodos , Infecções por Helicobacter/diagnóstico , Helicobacter pylori , Biópsia , Superfície Corporal , Radioisótopos de Carbono , Feminino , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Gastroscopia , Meia-Vida , Infecções por Helicobacter/patologia , Humanos , Masculino , Estudos Prospectivos , Sensibilidade e Especificidade , Fatores Sexuais , Fatores de Tempo , UreiaRESUMO
Mature ponies fitted with permanent ileal cannulas were used in a 3 X 3 Latin square experiment to quantify prececal, postileal and total tract digestion of hay protein. Coastal Bermuda grass (CB), containing 11.7% crude protein, and two qualities of alfalfa, containing 15.0% (low-protein alfalfa; LA) and 18.1% (high-protein alfalfa; HA) crude protein, were fed in coarsely chopped form at 2% of body weight daily. Total tract apparent digestibility of the N in HA (73.8%) was higher than that in CB (57.0%; P less than .05) and was slightly higher than that in LA (66.1%; P less than .10). Nitrogen in LA was apparently more digestible than that in CB (P less than .05). Apparent prececal digestibilities of N in LA and CB were 1.3% and 9.6%, respectively, and were lower (P less than .05), or tended to be lower (P less than .10), than the 21.0% observed for HA. In relative terms, an average of 9.4% of the total N digestion occurred in the upper tract when CB and LA were fed, whereas 28.5% of total N digestion occurred in the foregut when HA was fed. There was a slightly higher concentration of total plasma free amino acids (P less than .10) at 1 h postfeeding when horses were fed alfalfa. Also, N retention was higher when ponies were fed HA (P less than .05) than when LA or CB were fed. Apparent postileal N digestibility was 52.5% for CB, 65.7% for LA and 66.9% for HA. Differences were not significant, and the large intestine appeared to compensate for the inefficiency of N digestion in the upper tract.(ABSTRACT TRUNCATED AT 250 WORDS)
