Steatorrhea

STEATORRHEA, fatty stool, fatty evacuations, "oily stool." It is observed predominantly in diseases of the pancreas, in the blockage of the pancreatic duct (duct of Wirsung), and sometimes also in Basedow's and Addison's diseases. Steatorrhea may also occur as a result of ingesting excessively large amounts of fat with food. Macroscopically, the fecal masses in steatorrhea acquire a characteristic grayish-clayish hue and, upon standing, form a coating on the surface resembling congealed tallow. In cases of severe impairment of fat cleavage and utilization processes (e.g., in severe lesions of the pancreas), the dry residue of the feces may contain up to 50–80% fat. In patients with impaired pancreatic function, after the administration of 250 g of oil, the excreta acquire a macroscopically easily determinable, characteristic appearance of a "fatty stool." Insufficient fat utilization, respectively steatorrhea, can however also occur with a relatively good and, in a number of cases, even unchanged process of fat splitting. Thus, in chronic pancreatitis, normal fat splitting may be observed with a loss of fat in the feces amounting to 70–80% (Gross). In the clinical evaluation of the symptom of steatorrhea, one should take into account the possibility of the appearance of a "fatty stool" due to obstruction of the common bile duct. The presence of a significant percentage of unassimilated fat in the intestine in the absence of jaundice can serve as one of the reference points for diagnosing a disease of the pancreas. In phenomena of bile duct obstruction, the excreta, which acquire an acholic, clay-like appearance, contain a large amount of fatty acids. The absence of neutral fat in the feces in these cases is explained by the possibility of its cleavage by pancreatic juice in the absence of bile. The presence of a significant amount of neutral fat in the feces is at the same time a characteristic sign indicating a lesion of the pancreas. Fatty stool in diseases of the pancreas, while containing significant amounts of fatty acids, does not usually contain fatty acid crystals (Gross), whereas in bile duct obstruction, the finding of needle-shaped fatty acid crystals is characteristic. This sign is explained by the property of bile to dissolve fatty acids, preventing the precipitation of crystals (Kruspe, Ehrmann). In diseases of the pancreas, an increased excretion of lecithin with the feces may also take place. While normally the dry residue of feces contains about 1% (0.5–1 g) of lecithin, upon pancreatic lesion its amount in the feces increases to 1.97% (3.61 g). Significant amounts of fatty acid crystals and soaps can be found in the feces during catarrhal processes in the small intestines. These data of fecal microscopy, found in parallel with diarrhea, a number of dyspeptic phenomena and abdominal pain sensations arising shortly after eating, as well as simultaneously with zones of hyperesthesia in the region of segments corresponding to the small intestines, and radiological data indicating accelerated passage of the contrast mass, can serve as reference points for the diagnosis of enteritis (Porges, Essen). Literature—see literature to the article Feces.