Finding Virtual Colonoscopy's Role
Colonoscopy is the most sensitive screening test for colon cancer and polyps, reported Don C. Rockey, M.D., of Duke University Medical Center, Durham, N.C., and his colleagues.
But variability in the results of studies comparing virtual colonoscopy with conventional colonoscopy suggest that it's too soon to dismiss virtual colonoscopy, Steve Halligan, M.D., and Wendy Atkin, M.D., of St. Mark's Hospital, Northwick Park, England, said in an editorial.
In Dr. Rockey's prospective, multicenter study, 614 patients with a high likelihood of having colon abnormalities underwent air contrast barium enema, computed tomographic colonography (CTC—also known as virtual colonoscopy), and conventional colonoscopy.
Conventional colonoscopy consistently had a sensitivity of about 99% per patient for lesions 10 mm or larger, 6-9 mm, and 5 mm or smaller, whereas CTC had lower sensitivity for lesions of 10 mm or larger (59%), 6-9 mm (51%), and 5 mm or smaller (45%). Barium enema fared even worse, with sensitivity in each patient of 48% for lesions 10 mm or larger, 35% for 6-9 mm, and 32% for 5 mm or smaller. The reference standard used in the study was the combined data set for all three procedures (Lancet [online] Dec. 17, 2004;www.thelancet.com
The investigators also found that experienced radiologist observers (more than 50 CTC cases) did not detect lesions any better than did those with less experience who completed a CTC training module, although other studies have reported dissimilar findings, according to Dr. Halligan and Dr. Atkin (Lancet [online] Dec. 17, 2004;www.thelancet.com
HCV Therapy During HIV Coinfection
Pegylated interferon alfa-2b plus ribavirin is more effective than standard interferon alfa-2b plus ribavirin in treating patients with hepatitis C viral infections of genotype 1 or 4 who are coinfected with HIV, reported Fabrice Carrat, M.D., of Université Paris 6, and associates.
Significantly more patients infected with genotype 1 or 4 hepatitis C virus (HCV) developed a sustained virologic response (SVR) with peginterferon alfa-2b (Peg-Intron) plus ribavirin (Rebetol) than with interferon alfa-2b (Intron A) plus ribavirin (17% of 125 patients vs. 6% of 129 patients) at the end of 72 weeks of treatment. The SVR rate did not differ between the two groups among patients infected with HCV of genotype 2, 3, or 5 in the randomized, open-label study. An SVR in patients with HCV genotype 1 or 4 infection was associated independently with peginterferon treatment and an HCV viral load of 5.7 log10 IU × 103/L or less (JAMA 2004;292:2839-48).
Dr. Carrat and some of the other investigators reported receiving research grants or travel grants from and/or serving as a consultant to Schering-Plough, which markets Peg-Intron, Intron A, and Rebetol.
Fat and Fiber in Risk for GERD
A diet high in fat may be associated with an increased risk of gastroesophageal reflux disease and erosive esophagitis, reported Hashem B. El-Serag, M.D., of the Houston Veterans Affairs Medical Center, and his colleagues (Gut 2005;54:11-7).
A total of 371 employees from the Houston VA Medical Center fully answered questions to a cross-sectional survey. A high fat intake was associated significantly with GERD symptoms in overweight individuals, although it was not associated with an increased risk of esophageal erosions. Fiber intake was inversely associated with the risk of GERD symptoms after adjustment for body mass index, total energy intake, and demographic variables. The researchers cautioned that body mass index might have had modifying effects on the associations between fat and fiber intake and GERD symptoms. Avoidance or increased intake of certain foods as well as the level of physical activity might have affeccted the development of GERD in the survey respondents.
Mexican Genetic Link to Gallstones
Mexicans with gallstone disease appear to have a genetic predisposition to develop the condition, according to the results of a prospective, case-control study.
A significantly higher percentage of 146 patients with gallstone disease (GD) had a family history of the disease (48%), compared with 28% of 955 control patients without the disease, said Nahum Méndez-Sánchez, M.D., and colleagues at the Medica Sur Clinic and Foundation, Mexico City (Am. J. Gastroenterol. 2004;99:2166-70).
Patients with a history of GD were significantly more likely to have the HLA antigen allele B39 than were control patients (16% vs. 6%). Control patients were significantly younger on average than the GD patients (45 years vs. 54 years) and had a significantly lower average body mass index (26.4 kg/m2 vs. 27.4 kg/m2).