David J. Hentges

Bacteremia during colonoscopy

Bacteremia, including potentially pathogenic species of the fecal flora, was detected during colonoscopy in 6 of 22 patients when blood cultures were taken at frequent intervals during the first 15 minutes of the procedure. While transient bacteremia during colonoscopy may be insignificant for most patients, the implications are potentially more grave for those with valvular heart disease or compromised host defenses.

Gas-liquid chromatography of fecal neutral steroids☆

Abstract A method is described for the analysis of fecal neutral steroids with a dual-column gas-liquid chromatography (GLC) system. After saponification of the fecal slurry, the neutral steroids were extracted with hexane. The GLC separation of the compounds and quantitation were achieved by simultaneous injection of the derivatized and underivatized aliquots of the extract onto dual columns under identical conditions. The neutral steroids of interest were then identified by matching the retention times with those of known standards, and identification was confirmed by use of an interfaced GLC high-resolution mass spectrometry system. The detection limit was 0.003 mg of steroid/g of fecal slurry. The precision of the method is illustrated by a relative standard deviation of 2–10% and a recovery of neutral steroids from 73–96%. The method was applied to the determination of fecal neutral steroids in a “High protein diet in colon cancer study”. A considerably larger level of coprostanone than of coprostanol was observed. Data on neutral steroids in fecal samples from subjects on different diets are the subject of a separate publication.

Fecal flora of volunteers on controlled diets

Ten volunteers completed a 4-month diet series consisting of a control diet, a meatless diet, a high-beef diet, and the same control diet, each lasting 1 month. Fat and fiber contents were essentially the same in all four diets, but protein content was doubled during the high-beef diet. High-beef protein consumption had little effect on the composition of the intestinal flora of the volunteers. There were no significant differences detween the high-beef and meatless diets in total numbers of anaerobic, facultative, or aerobic organisms isolated, nor were there major differences in the counts of the individual genera and species of bacteria encountered. The data indicate that animal protein consumption has little effect on the fecal bacterial profile in humans. The possible influence of animal fat consumption on the metabolic activities of intestinal bacteria is discussed.

Excretion of creatine and creatinine in feces of man.

Summary To examine the effects of a high beef diet on the bacterial flora and chemical composition of feces, 10 healthy human adults were fed four diets in succession for 1 month each: a control diet, meatless diet, high beef diet, and a repeat control diet. As a part of the larger study, creatine and creatinine were measured in the food consumed and in the feces excreted. Food creatine concentration was 5- to 12 -fold greater than creatinine; food creatine and creatinine were increased 4- and 10-fold, respectively, in the high beef diet compared with the control diets. Fecal creatine concentration was significantly elevated during the high beef diet (1.3-fold) over that in the control diets, whereas fecal creatinine excretion was elevated with only the meatless diet. Thus, creatinine and creatinine are present in human feces, and dietary creatine has an incomplete absorption during consumption of high beef diets.