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

Cholestyramine, colestipol, clofibrate, gemfibrozil, nicotinic acid (niacin), probucol, neomycin, and dextrothyroxine are the most commonly used drugs in the treatment of hyperlipoproteinaemic disorders. While adverse reaction data are available for all of them, definitive data regarding the frequency and severity of potential adverse effects from well-controlled trials using large numbers of patients (greater than 1000) are available only for cholestyramine, clofibrate, nicotinic acid and dextrothyroxine. In adult patients treated with cholestyramine, gastrointestinal complaints, especially constipation, abdominal pain and unpalatability are most frequently observed. Continued administration along with dietary manipulation (e.g. addition of dietary fibre) and/or stool softeners results in diminished complaints during long term therapy. Large doses of cholestyramine (greater than 32 g/day) may be associated with malabsorption of fat-soluble vitamins. Most significantly, osteomalacia and, on rare occasions, haemorrhagic diathesis are reported with cholestyramine impairment of vitamin D and vitamin K absorption, respectively. Paediatric patients have been reported to experience hyperchloraemic metabolic acidosis or gastrointestinal obstruction. Concurrent administration of acidic drugs may result in their reduced bioavailability. Serious adverse reactions to clofibrate will probably limit its role in the future. Of particular concern are ventricular arrhythmias, induction of cholelithiasis and cholecystitis, and the potential for promoting gastrointestinal malignancy which far outweigh the reported benefits in preventing new or recurrent myocardial infarction, cardiovascular death and overall death. Patients with renal disease are particularly prone to myositis, secondary to alterations in protein binding and impaired renal excretion of clofibrate. Drug interactions with coumarin anticoagulants and sulphonylurea compounds may produce bleeding episodes and hypoglycaemia, respectively. Nicotinic acid produces frequent adverse effects, but they are usually not serious, tend to decrease with time, and can be managed easily. Dermal and gastrointestinal reactions are most common. Truncal and facial flushing are reported in 90 to 100% of treated patients in large clinical trials. Significant elevations of liver enzymes, serum glucose, and serum uric acid are occasionally seen with nicotinic acid therapy. Liver enzyme elevations are more common in patients given large dosage increases over short periods of time, and in patients treated with sustained release formulations.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Adverse effects of hypolipidaemic drugs. 354 4

The results of the measurement of vitamin B(12) absorption by counting the radioactivity of 5 ml. serum obtained eight to 10 hours after the ingestion of an oral dose of 0.5 mug. vitamin B(12) labelled with 0.5 muc. (57)Co are compared with those obtained with the urinary excretion (Schilling) test. Inadequate urine collection and impaired renal function were responsible for low results in the Schilling test in four of the 12 control subjects, and an incomplete urine collection in four patients with pernicious anaemia could have led to doubt about the validity of the low result. The measurement of serum radioactivity for 1,000 seconds gave conclusive results, the range in the patients with malabsorption of vitamin B(12) being between 0 and 24 counts per minute, and in the control subjects and other patients with megaloblastic anaemia between 28 and 64 counts per minute. The highest serum radioactivity level in a patient with pernicious anaemia was 19 counts per minute. Serum counting is simpler than the Schilling test and may be done alone when the patient's renal function is known to be poor, when urine collection is expected to be unreliable, or when the flushing dose of vitamin B(12) should be avoided. Otherwise there is an advantage in doing both tests together for confirmation.
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PMID:Measurement of intestinal absorption of 57-Co vitamin B-12 by serum counting. 592 10

The classical symptoms of malabsorption syndrome are diarrhea, steatorrhea, weight loss, and fatigue. Tetany, ecchymosis, anorexia, bone pain, pallor, muscle wasting, hyperpigmentation, apathy, digital clubbing, abdominal distention which contrasts in view of the reduced common statement are other signs of malabsorption. Long before the onset of these symptoms there may be a disinterest in regular daily activities often associated with the passage of three soft stools per day and with the remarkable sign of difficulties in flushing bulky stools. Anamnesia, clinical examination in connection with common laboratory findings, small intestinal x-rays and endoscopic investigations associated with biopsies of the small (and large) bowel as well as estimation of stool fat excretion, xylose- and Schilling-test allow the diagnosis in most of the cases.
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PMID:[Clinical aspects and differential diagnosis of malabsorption]. 684 29

The carcinoid syndrome, associated with carcinoid tumors of the midgut, consists of symptoms such as diarrhea, flushing, wheezing and cardiovascular symptoms. This review focuses on these symptoms and discusses therapeutic options. The symptoms are caused by the secretion of biogenic amines, polypeptides and other factors of which serotonin is the most prominent. However, diarrhea is also due to factors such as malabsorption. Besides antitumor therapy, more specific interventions such as serotonin receptor blockers can be useful. The carcinoid heart disease involves the tricuspid and pulmonary valve. In the pathogenesis, serotonin plays a central role. The therapeutic approach is mostly symptomatic. Other cardiovascular complications include bowel ischemia and hypertension. Pellagra and psychiatric symptoms are due to a depletion of tryptophan, which is consumed by the carcinoid tumor for serotonin synthesis. Finally, follow-up and clinical practice of patients with carcinoid tumors are discussed.
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PMID:Complications of midgut carcinoid tumors and carcinoid syndrome. 1547 13

Measuring heavy metal levels in the urine is an accepted method for assessing the presence of a heavy metal burden in an individual. Random samples (without a flushing agent) are excellent for showing current exposures, as they reflect the level of heavy metals in the bloodstream during the hours immediately before bladder voiding. Samples taken after using a heavy metal mobilizing agent are a reflection of total body burden. Part 1 reviewed the benefits of doing pre-flush (baseline) testing utilizing the published Centers for Disease Control (CDC) heavy metal normal ranges for interpretation that allow the clinician to identify current exposures to lead and mercury and to identify cadmium toxicity. In part 2 the benefits of doing both pre- and post-challenge testing are reviewed. Information gleaned from performing both tests is unparalleled in allowing the clinician to identify which chelating agent will be most effective for the patient. If oral agents are employed, then possible absorption problems can be identified. Since none of these benefits are realized with only post-flush testing, it is recommended that clinicians do heavy metal testing both before and after a challenge with an effective and proven heavy metal mobilizing agent. The pitfalls of oral chelation in the case of malabsorption syndromes, such as gluten intolerance, are also discussed.
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PMID:The benefit of pre- and post-challenge urine heavy metal testing: part 2. 1959 21

Neuroendocrine tumors (NETs) arise from enterochromaffin cells found in neuroendocrine tissues, with most occurring in the gastrointestinal tract. The global incidence of NETs has increased in the past 15 years, likely due to better diagnostic methods. Small-bowel NETs are frequently associated with carcinoid syndrome (CS). Carcinoid syndrome diarrhea occurs in 80% of CS patients and poses a substantial symptomatic and economic burden. Patients with CS diarrhea frequently suffer from diarrhea and flushing and report corresponding impairment in quality of life, requiring substantial changes in daily activities and lifestyle. Treatment paradigms range from surgical debulking to liver-directed therapies to treatment with somatostatin analogs, nonspecific anti-diarrheal agents, and a tryptophan hydroxylase inhibitor. Other causes of diarrhea, including steatorrhea, short bowel syndrome, and bile acid malabsorption, should be considered in NET patients with refractory diarrhea. More therapeutic options are needed for symptomatic management of patients with NETs, and better understanding of the pathophysiology can empower clinicians with improved patient care.
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PMID:Management of Diarrhea in Patients With Carcinoid Syndrome. 3142 82