Hyperkalemia must be avoided if possible and treated promptly if present (see HYPERKALEMIA in Ch. 3). Gastrointestinal bleeding, which is often aggravated by azotemia, is a common cause of hyperkalemia because potassium is absorbed from lysed red cells in the gut. Acidosis progresses with the duration and degree of renal failure, and sodium bicarbonate should [...]
In clinical medicine, attempting !o separate the effects of aging from those of disease is a recurring challenge. The elderly who have no significant disease but whose biologic age appears greater than (heir chronologic age (as determined largely by functional assessment) are described as “frail.” Understanding the role of such frailty in liver aging isjust [...]
. Pancreatic exocrine or endocrine insufficiency develops without pain in some patients, especially elderly patients, many of whom have associated pancreatic calcification. Etiology In the elderly, the most common forms of chronic pancreatitis with pancreatic insufficiency result from heavy alcohol intake for more than 15 yr, trauma, vascular disease, abdominal radiation therapy, and pancreatic carcinoma. [...]
In healthy adults, the proximal lumen of the small intestine contains 0 to 104 microorganisms per milliliter, consisting of aerobes and facultative anaerobes, which are largely oral flora. This relative sterility is maintained by normal gastric acid secretion, normal peristalsis of the proximal small intestine, and luminal immunoglobulins. In persons age 70 and older, however, [...]
With fat malabsorption, microscopic examination of a stool specimen stained with Sudan III reveals increased tat droplets. A 24-h stool specimen usually weighs more than the normal 200 gm. Chemical fat determination of a 3- to 6-day stool specimen obtained while the patient ingests a 100-gtn fat diet shows fat excretion of IOlo40gm/24 h (normal [...]
A genetic disease involving malabsorption of many nutrients, resulting from characteristic, if not specific, pathologic changes in the small intestinal mucosa induced by ingestion of the giiadin fraction of gluten. Giiadin is a mixture of high-molccular-weight cereal proteins found in wheat, rye, oats, and barley. In mosl patients, prompt clinical, biochemical, and histologic improvement follows [...]
The nutritional status of elderly persons is influenced by (he effects of age on nutrient digestion and absorption. Aging does not significantly affect the structure and function of the exocrine pancreas, nor does it impair digestive capacity. Maldigestion and malabsorption occur only when more than 90% of pancreatic function is lost. Similarly, the small intestine [...]
The principal pathogens include Shigella, Salmonella, Campylobacter, and Yersinia. The latter two are seen predominantly in children and young adults. These four invasive pathogens involve the distal ileum and colon, producing mucosal ulceration. SH?GELLOS?S Shigellae are a group of gram-negalive enteric organisms. Four major subgroups exist: group A-serotypcs of Shigella dysenteriae, group B-serotypes of Shigella [...]
At least five types of Escherichia coli can cause GI infections, including enterotoxigenic, enteropathogenic, enteroinvasive. enterohemorrhagic, and enteroadhercnt E. colt. Enterotoxigenic E. colt comes from contaminated waler and causes a subacute illness with a 24- Lo 72-h incubation period. This illness is associated wilh diffuse, mild abdominal pain; foul-smelling, profuse watery diarrhea; and occasional vomiting. [...]
Vitamin B]2 deficiency accounts for up to 9% of all anemias in elderly people. Potentially more important. 3% to 12% of all elderly people have low serum vitamin B12 levels. Because neurologic damage and dementia may occur before anemia or any hematologic changes are found, early detection of vitamin B12 deficiency is important. Etiology In [...]
