Fecal fat excretion

Fig. 9. Effect of short-term rifaximin administration (400 mg t.i.d. for 7 days) on diarrhea (a) and fecal fat excretion (b) in patients with chronic pancreatitis with and without SIBO (from Trespi and Fer-rieri [201]).

In addition to ANP where it is associated with GI dys-motility [198, 199], SIBO is present in a significant proportion of patients with chronic pancreatitis [200, 201], Short-term rifaximin therapy was able to normalize the hydrogen breath test and improve symptoms (i.e. diarrhea and fecal fat excretion) in all patients studied (fig. 9) [201]. Bowel decontamination via administration of this topical antibiotic could, therefore, be beneficial in both acute and chronic pancreatitis. Double-blind, placebo-controlled studies are to be performed to explore the rifaximin potential in this indication. 

All. Asenjo, C. F., Rodriguez-Molina, R., Cancio, M., and Bemabe, R. A., Influence of very low fat diets, with and without gluten, on the endogenous fecal-fat excretion of patients with tropical sprue. Am. J. Trop. Med. Hyg. 7, 347-352 (1958). 

Octreotide 100 pg given subcutaneously to five healthy subjects 30 minutes before meals for 7 days increased fecal fat excretion however, steatorrhea occurred in only two cases fecal bile acid excretion fell to about 25% (35)... 

Jacobsen, R., Lorenzen, J. K., Toubro, S., Krog-Mikkelsen, I., and Astrup, A. (2005). Effect of short-term high dietary calcium intake on 24-h energy expenditure, fat oxidation, and fecal fat excretion. Int. J. Obes. (Lond.) 29, 292-301. 

Gades, Matthew D., and Judith S. Stern. "Chitosan Supplementation and Fecal Fat Excretion in Men." Obesity Research 11 (2003) 683-688. Available online. URL www. obesityresearch. org/cgi/content/abstract/11/5/683. Accessed November 13, 2007. 

Quantitative fecal fat excretion was markedly increased (28 g/day normal is <7 g/day), and fecal elastase 1 concentration was reduced to 24 pg/g (lower level of normal is 200 pg/g).The patient was diagnosed with severe pancreatic exocrine (but not endocrine) insufficiency due to alcoholic chronic calcifying pancreatitis and advised to stop alcohol and cigarette consumption. 

The coefficient of fat absorption is defined as the amount of fat absorbed as a percentage of the ingested amount. This coefficient normally exceeds 93% and is used (rather than crude fecal fat excretion) to indicate efficacy of luminal fat digestion following different dietary lipid intakes. By contrast, fecal carbohydrate measurements do not fully reflect the extent of starch malabsorption because carbohydrates are metabolized by the intracolonic microbial flora. Since intracolonic metabolism of carbohydrates... 

Measurement of stool weight and quantitative fecal fat excretion on three consecutive days during a balanced diet are common screening tests for both pancreatic insufficiency and other pathologies that result in malabsorption. However, these tests are insensitive and nonspecific for pancreatic malfunction Steatorrhea occurs only after loss of more than 90% of exocrine parenchyma, and other causes of malabsorption (e.g., celiac sprue or Crohn s disease) may also induce abnormal fecal fat excretion of more than 7 g/day or more than 5 g/100 g. 

No significant differences were found in mean fecal fat excretions (Table VIII). Failure to detect differences in fecal fat may indicate that the increase in total fat content of the usual versus the modified fat diet is compensated for by an increase in absorption of fat. Increased absorption of fat, then, could account for the higher serum HDL-cholesterol and triglycerides levels caused by the two higher fat treatments. 

In conclusion, serum, liver and brain lipid concentrations, body weight change and fecal fat excretions were greater in rats fed a diet with 25% fat than in rats fed a lower fat diet. Within each level of fat, total liver lipids decreased and liver cholesterol concentration increased as level of dietary manganese increased. However, in 14 adult, human subjects fed two levels of dietary fat, dietary manganese had no effect on serum lipid parameters or fecal fat excretion. 

Table VIII. Mean Fecal Fat Excretions (g/day) of Humans Fed Varying Levels of Manganese and Fat...

It is also often forgotten that diarrhea increases fecal fat excretion. In 58% of subjects with normal fat excretion, experimental induction of severe diarrhea (fecal weight >800g/day) led to increased fecal fat (values of up to 49mmol/day). A borderline increase in fecal fat (i.e., 2 to 3 times the upper limit of normal, which is 18mmol/day) is therefore not specific for a primary defect in fat digestion or absorption. 

Fine KD, Fordtran JS. The effect of diarrhea on fecal fat excretion. Gastroenterology 1992 102 1936-9. 

Similar experiments were performed without gastric and duodenal tubes, and fat absorption was indirectly measured from fecal fat excretion. As predicted from... 

Chung, )., Kinberg, J., Hauptman, J.B. and Patel, LH. (1994) Retrospective population-based analysis of the dose-response (fecal fat excretion) relationship of orlistat in normal and obese volunteers. Clin. Pharmacol. Ther. 56, 82-85. 

Increased excretion of cholesterol is thought to be the mechanism for reducing serum cholesterol. Several investigators have reported increased fecal fat (7,19), sterols (7,9,19.26) or bile acids (7,9, 29,30). Kay and Truswell T) reported significant increases in fecal fat excretion, averaging 44% fecal cholesterol. 

When fecal fat excretion (Fig. 2) was determined over the 24-h period following the ingestion of butter, safflower oil or fish oil before and after the 4-week period of fish oil capsule treatment, there were clear indications that the ingestion of large quantities of fish oil in form of a fat load caused severe steatorrhea. This was particularly evident after the treatment period with fish oil capsules. 

Fig. 2. Fecal fat excretion over a 24-h period following the ingestion of butter, safflower oil or fish oil before and after a 4-week period of fish,oil capsule treatment...

The effect of low fat intakes and of crude fiber has been studied by Walker by means of balance studies on a healthy European male. When a large increase was made in the crude fiber content of equal fat diets, the amount of fecal fat excreted detectably increased. This was considered not to have been derived directly from the food. The possibility was raised by Walker that it might be of microbial origin. 

The role of undigested nutrients has been postulated, following the observation that, when pancreatic enzyme supplementation was withdrawn, CF patients showed a fecal BA output which was comparable to that observed in children with ileal resection[5]. Substitutive therapy was followed by a partial but consistent amelioration in BA loss. In basal conditions, a positive and significant correlation between fecal BA and fecal fat excretion was found and unhydrolyzed triglycerides and/or free fatty acids have been considered as the most responsible factors inhibiting BA absorption in CF. 

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