Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0024523 (malabsorption)
 7,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Small bowel enteroscopy in 1991 is now feasible in two clinical situations: in the case of malabsorption or diffuse intestinal disease, it is easier to visualise the small bowel with the "push enteroscopy methods". The most proximal and distal ends of the small intestine can be viewed through standard instruments or better with videocoloscope beyond the ligament of Treitz. The ileocecal valve can be intubated after total colonoscopy for the evaluation of Crohn's disease, tuberculosis and small bowel lymphoma. In the case of occult gastrointestinal hemorrhage small bowel enteroscopy now permits visualization of large amounts of small intestinal. When the gastrointestinal bleeding is severe, we recommend intraoperative enteroscopy. When the bleeding is not severe and chronic, it is possible to perform a non surgical total small bowel enteroscopy with an enteroscope or videoenteroscopoe. Prototypes are under development. The procedure is safe an can be performed on an outpatient basis. The limitations of the procedure are the impossibility of intervention and inability to inspect the total mucosal surface. It is not a "first line" or "second line" investigation in these situations. It should be considered after previous investigations have been negative. Push enteroscopy should be performed by general endoscopists, non surgical and total enteroscopy should be reserved, for instance for skills and motivated team endoscopists.
 ...
PMID:[Endoscopy of the small intestine in 1991: is it the end of the tunnel?]. 141 52

Serum 25-hydroxyvitamin D declines in elderly subjects. This decrease reflects, in part, a lower vitamin D intake. But changes in serum 25-hydroxyvitamin D are more marked in the northern latitudes of the world because less vitamin D synthesis occurs n the skin as a result of a reduced amount of ultraviolet light. Consequently, vitamin D deficiency leading to osteomalacia is more common in thr northern latitudes, particularly among the elderly. The Recommended Daily Allowance of 200 IU of vitamin D in the elderly may be insufficient, since higher doses of 800 IU/day have been shown to reduce the incidence of osteoporotic fractures. The use of more potent analogues of vitamin D, such as calcitriol (Rocaltrol), should be reserved only for those patients who have established vertebral osteoporosis and who generally have more pronounced malabsorption of calcium.
 ...
PMID:Vitamin D metabolism and therapy in elderly subjects. 150 13

Congenital and acquired diverticula of the jejunum and ileum in the adult are unusual and occur in approximately 1 percent to 2 percent of the population. They are pulsion diverticula thought to be the result of intestinal dyskinesia. These lesions can produce a significant diagnostic and therapeutic dilemma. They are multiple in the jejunum and solitary distally and are characteristically found in 60- or 70-year-old males. The diagnosis may be confirmed with contrast studies of the small intestine, arteriography, or nuclear scan. Consider these disorders in patients with 1) unexplained gastrointestinal bleeding, 2) unexplained intestinal obstruction, 3) an unexpected cause of acute abdomen, 4) chronic abdominal pain, 5) anemia, or 6) malabsorption. Medical therapy is helpful in controlling diarrhea and anemia, while surgical therapy is reserved for hemorrhage, obstruction, perforation, or failure of medical management. Asymptomatic diverticula discovered on routine contrast studies need not be resected. At surgery, incidental diverticula should be removed when evidence of dilated, hypertrophied loops of small bowel with large diverticula is found. Intraoperative air distention will aid in diagnosis. Resection and primary anastomosis is the preferred treatment for non-Meckelian diverticula. Diverticulectomy is reserved for a Meckel's diverticulum without evidence of ulceration. An incidental Meckel's diverticulum should be removed in the presence of mesodiverticular bands or ectopic tissue. Removal of a Meckel's diverticulum is not advised in the patient with Crohn's disease but may be performed in the patient undergoing restorative proctocolectomy for ulcerative colitis.
 ...
PMID:Clinical implications of jejunoileal diverticular disease. 158 62

In this review paper the main properties of elemental, semi-elemental and polymeric diets utilized in enteral nutrition are compared. The theoretical value of elemental diets (they do not require digestion) is upset by their effects on secretion. Semi-elemental diets are not hyperosmolar and are easily absorbed. Polymeric formulas acan be given in almost all indications of enteral nutrition, and in view of the high cost of elemental and semi-elemental diets, the latter should be reserved to elective indications, notably antigenic arrest of the digestive tract and major nitrogen malabsorption.
 ...
PMID:[Elemental, semi-elemental, polymeric diets. Choice, indications, rational use]. 190 76

Reduction in acid secretion in atrophic gastritis allows bacterial colonization of the stomach, most extremely in achlorhydric patients with pernicious anaemia, in whom overgrowth may cause nitrate reduction and formation of potentially carcinogenic N-nitroso compounds. Subsequent bacterial contamination of the upper small intestine can induce mucosal damage and malabsorption. The situation is similar after gastrectomy. In achlorhydria and after gastrectomy, the risk of gastric cancer is increased. There is controversy as to the risks of long-term treatment with H2-receptor antagonists. Increase in nitrate-reducing bacteria, nitrite and N-nitrosamine have been observed in patients by some investigators but not in volunteers and patients by others. Bacterial concentrations after cimetidine are inversely related to pretreatment acid secretory capacity. Demonstration of increased mutagenicity of gastric juice after H2-receptor antagonists gives grounds for caution. Drastic acid reduction may in future be reserved for short-term and intermittent treatment and mild or moderate reduction for long-term treatment of peptic ulcer and ulcer prevention.
 ...
PMID:Bacterial overgrowth as a consequence of reduced gastric acidity. 286 52

Elucidation of the vitamin D endocrine system and the availability of potent metabolites have led to new approaches to vitamin D therapy. The traditional management of exogenous (sunlight) or endogenous (malabsorption) vitamin D deficiency without evidence of disordered vitamin D metabolism has not changed, since it consists of treatment with vitamin D itself--a therapy which preserves the normal intrinsic mechanisms for regulating the rate of production of 1,25-dihydroxycholecalciferol. 1,25-DHCC and the analogue compound 1 alpha-CC should be reserved for treatment of hypocalcemia consequent on chronic renal failure or hypoparathyroidism, where 1-hydroxylation is lacking or impaired. Hypophosphatemic rickets has been treated with 1-hydroxylated compounds, with promising results; this use of the latter metabolites warrants further investigation. The use of vitamin D metabolites and of pharmacological doses of vitamin D itself must be regarded as substitution of a hormone or hormone precursors. Therefore, careful monitoring of serum and urine calcium is required in every patient receiving these compounds, in order to avoid excessive dosage. Special attention must be paid to patients with sarcoidosis since they often develop hypercalcemia after vitamin D or UV-light exposure, as a result of an intrinsic regulation defect in 1,25-DHCC synthesis.
 ...
PMID:[Therapy with vitamin D and D-metabolites]. 626 26

Patients with jejunal diverticula usually are asymptomatic unless bacterial overgrowth within the diverticula is sufficient to cause vitamin B12 deficiency, by direct uptake of the vitamin by the bacteria, or malabsorption resulting from bacterial deconjugation of bile salts and impaired lipid digestion. The administration of broad-spectrum antibiotics usually constitutes effective treatment that suppresses bacterial flora, with surgery reserved for complications such as hemorrhage, perforation, and abscess formation, and acute or chronic intestinal obstruction. Our patient had many diverticula, and two courses of antibiotics failed to provide prolonged relief of symptoms. After surgical exploration to exclude the presence of partial intestinal obstruction or infiltrating disease of the terminal ileum, the segment of jejunum bearing diverticula was resected. Since operation the patient has remained asymptomatic, which suggests that in certain patients, even with many diverticula, surgical exploration and excision of the diverticula may be curative.
 ...
PMID:Malabsorption in jejunal diverticulosis treated with resection of the diverticula. 677 18

Short bowel syndrome is the clinical manifestation of a fundamental reduction in the functional intestinal absorptive surface area and malabsorption. The development of total parenteral nutrition has improved the natural course of this disease. Home parenteral nutrition-related complications continue to generate significant morbidity and mortality for these patients. Small-bowel transplantation is an alternative to home parenteral nutrition. There are significant risks of graft rejection and the potential complications of long-term immunosuppression. Small-bowel transplantation is an option, but it should be reserved for patients no longer considered candidates for continued home parenteral nutrition.
 ...
PMID:The current role of small-bowel transplantation in intestinal failure. 845 29

Jejunoileal diverticula are estimated to occur in 1-5% of the population. The incidence increases with age, peaking at the sixth and seventh decades. The pathogenesis is believed to involve an acquired defect of the intestinal smooth muscle or myenteric plexus. Eighty percent of jejunoileal diverticula are localized to the jejunum, 15% to the ileum, and 5% to both. Diverticula in the jejunum tend to be large and multiple, whereas those in the ileum are small and solitary. Symptoms of intermittent abdominal pain, flatulence, diarrhea, and constipation are reported in 10-30% of patients with jejunoileal diverticula. The radiographic diagnosis of these diverticula is difficult to establish. Enteroclysis should be reserved for patients who have persistent abdominal pain despite nonrevealing endoscopic and contrast enhanced studies of the upper and lower gastrointestinal tracts. Asymptomatic jejunoileal diverticula should be managed conservatively. Complications occur in 6-10% of patients and include obstruction, diverticulitis, hemorrhage, perforation, malabsorption, and chronic debilitating abdominal pain. When surgical therapy is indicated, intestinal resection with primary anastomosis is the preferred treatment.
 ...
PMID:Jejunoileal diverticula. 907 21

In the rapidly increasing elderly population, diarrhoea as a result of drug therapy is an important consideration. The elderly consume a disproportionately large number of drugs for multiple acute and chronic diseases. Drugs can compromise both immune and nonimmune responses. Aging decreases the quality and proportion of T cells which in turn reduces the production of secretory IgA, the primary immune response of the gut. Acid production in the stomach decreases with increasing age and this compromise its vital 'self-sterilising' function, thus increasing the risk of diarrhoea due to viral, bacterial and protozoal pathogens. Other nonimmune defence mechanisms include the motility of the small intestine and the host-protective commensal bacteria of the colon. Drug induced hypomotility may result in bacterial overgrowth, deconjugation of bile salts and diarrhoea. Less commonly, diarrhoea may occur due to hypermotility because of a cholinergic-like syndrome. In the colon the host-protective commensal bacteria provide a powerful defence against pathogens. Disruption of this commensal population by antibiotic therapy may result in Clostridium difficile supra-infection which causes diarrhoea through toxin production. This is especially important in the elderly patient on chemotherapy for malignancy and those with multiple diseases. The organism responds to vancomycin, metronidazole and bacitracin. Metronidazole is the suggested drug of choice, with vancomycin reserved for relapses. Drugs also cause diarrhoea by interfering with normal physiological processes. Drugs impair fluid absorption by activating adenylate cyclase within the small intestinal enterocyte which increases the level of cyclic AMP. This causes active secretion of Cl- and HCO3-, passive efflux of Na+, K+ and water and inhibition of Na+ and Cl- into the enterocyte. Examples of these drugs (secretagogues) are bisacodyl, misoprostol and chenodeoxycholic acid (used to dissolve cholesterol gallstones). Drugs may also affect a second mechanism that regulates water and electrolyte transport, the Na+, K+ exchange pump. The energy for this pump is provided by the ATPase mediated breakdown of ATP. ATPase may be inhibited by digoxin, auranofin, colchicine and olsalazine. A number of drugs cause osmotic diarrhoea including antacids containing magnesium trisilicate or hydroxide. Lactulose is being used increasingly in compensated liver disease to increase protein tolerance and prevent hepatic encephalopathy. Sorbitol, an osmotic laxative agent also used in some liquid pharmaceutical preparations, induces diarrhoea by virtue of its osmotic potential. Another mechanism by which drugs cause diarrhoea is by mucosal damage of the small and large bowel. In the small intestine mucosal damage causes diarrhoea and fat malabsorption, as may occur with neomycin and colchicine. In the colon, for example, gold salts and penicillamine cause colitis of varying severity. Though the causes of diarrhoea are diverse, a drug-associated aetiology should always be considered and actively sought and addressed to prevent the complications of dehydration, electrolyte imbalance and undernutrition.
 ...
PMID:Mechanisms of drug-induced diarrhoea in the elderly. 978 28


1 2 3 Next >>