Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017536 (giardiasis)
 1,714 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Infection with Giardia lamblia often causes only minor mucosal changes to the small intestine yet frank fat malabsorption may still occur. Some evidence suggests abnormal pancreatic exocrine function in subjects with giardiasis although the mechanism and significance of this is unclear. Studies were conducted in vitro to determine the effect of G. lamblia trophozoites or culture filtrates from the organism on lipolysis of triglyceride by porcine pancreatic lipase. Live trophozoites significantly inhibited lipolysis. The degree of inhibition increased with longer duration of lipase exposure to trophozoites. Total amounts of enzyme inhibited were proportional to enzyme concentration, while the percentage inhibition was greatest at lowest concentration. At a lipase concentration of 1.7 i.u./ml, enzyme activity was reduced by 89.7% compared to controls after incubation for 4 h with trophozoites. The effect was abolished using killed, intact trophozoites. Culture filtrates of G. lamblia did not inhibit lipolysis. Specificity of the effect was suggested by the failure of another flagellate protozoan, Trichomonas vaginalis, to inhibit lipase. In this assay system the inhibition of lipolysis was not dependent on the bile salt concentration present. The impact of this effect in vivo remains to be determined but it may contribute to fat malabsorption in giardiasis.
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PMID:The effect of Giardia lamblia trophozoites on lipolysis in vitro. 194 23

The clinical course of giardiasis is variable, and serum antibodies do not appear to be protective. We propose that natural factors either produced by intestinal tissue, transported into the intestine, or ingested (ie, by breast-fed babies) might promote resistance to this disease. Human milk is very rich in secretory IgA (S-IgA) antibodies, as well as nonspecific antibacterial factors (eg, lactoferrin, lysozyme). Previous studies showed that Giardia lamblia trophozoites were killed by nonimmune human milk (NHM) in a time- and concentration-dependent manner. Removal of greater than 99% of the S-IgA from NHM did not decrease its Giardia-cidal activity. Thus, the killing was not antibody dependent. This is the first demonstration of nonimmune antiparasitic defenses in human milk. The present studies show that in the presence of NHM, trophozoites lost motility, swelled, and lysed. The Giardia-cidal activity (GCA) may be specific to human milk, since unheated cow's and goat's milk were virtually devoid of activity. Much, but not all, of the GCA was lost when NHM was heated or reacted with diisopropylfluorophosphate (DIFP), a specific esterase inhibitor. Activity of the major human milk lipase (BSL, bile salt-stimulated lipase, a fatty acid esterase) was lost after heat or DIFP treatment and was absent from cow's or goat's milk. The parasites were also killed by pure BSL. These studies suggest that BSL may be a heat-labile Giardia-cidal component of NHM.
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PMID:Killing of Giardia lamblia trophozoites by normal human milk. 667 55

We studied six patients with giardiasis (five males, one female), median age 3.5 yr (range 1-11) and 12 healthy control subjects (10 males, 2 females), median age 3.5 yr (range 1-10). Intestinal biopsy and a contemporaneous secretin-cerulein test were performed in all patients, and fecal chymotrypsin was also assayed. Intestinal biopsy was normal in five of the six patients with giardiasis, whereas one of the six presented a partial atrophy of the intestinal villi. The secretin-cerulein test (1 CU/kg of secretin + 75 ng/kg of cerulein) did not show any significant difference between values in the outputs of chymotrypsin, lipase, phospholipase, and bicarbonate obtained in patients and in controls; however, in the one patient with partial intestinal mucosal atrophy, all enzymatic activity levels were below the normal limit for our laboratory. Furthermore, the mean values of fecal chymotrypsin concentration did not differ between the two groups. Fecal chymotrypsin was also reduced in the patient with an abnormal secretin-cerulein test; a second assay performed 3 mo after the suspension of treatment (Metronidazole), however, showed a normal chymotrypsin concentration.
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PMID:Secretin-cerulein test and fecal chymotrypsin concentration in children with intestinal giardiasis. 828 80

Effective treatment of malabsorption due to severe pancreatic exocrine insufficiency requires delivery of sufficient enzymatic activity into the duodenal lumen simultaneously with meal nutrients. To achieve this, modern therapeutic concepts recommend administration of 25,000 to 40,000 units of lipase per meal using pH-sensitive pancreatin microspheres. In case of treatment failure, dosage should be increased two to three times. If this still is not successful, compliance may be checked by measurement of fecal chymotrypsin, although this is not a standardized procedure. In the compliant patient, diagnosis of pancreatic exocrine insufficiency needs to be reviewed, particularly cases of celiac disease, (concomitant) bacterial overgrowth, and blind loop syndrome, as well as giardiasis, which need to be excluded or otherwise be treated specifically. Finally, additional acid suppression with application of unprotected pancreatin and/or reduced fat intake may help to control malabsorption. Still, in most patients, lipid digestion cannot be completely normalized by current standard therapy. On the one hand, this leads to loss of energy that may only partly be compensated for by increased nutrient intake. On the other hand, increased nutrient exposition of distal intestinal sites may release excessive amounts of mostly inhibitory distal intestinal neurohumoral mediators, and thereby disturb gastrointestinal secretory and motor functions. Consequently, future developments are needed for optimizing treatment.
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PMID:Pancreatic Enzyme Supplementation Therapy. 1295 43

The study of the effect of Giardia lamblia and Helicobacter pylori organisms coexistence on the activities of urease and lipase enzymes was the aim of this work which was done through choosing 50 cases of giardiasis in addition to 10 normal individuals chosen as a control group (free from giardiasis). It is well known that H. pylori is considered one of the most important causes of gastric and duodenal inflammations which could predispose to ulcers and hypochlorhydria leading to increased susceptibility to giardiasis as it is known that HCl acts as a chemical barrier to microbes. The biochemical tests were done to investigate the activity of both urease and lipase enzymes extracted from the gastric juice of patients and controls. A significant increase in urease activity in the group having combined infection (giardiasis and H.pylori) than the group infected with G.lamblia alone and the control group was found. The same findings were obtained regarding the lipase activity. In the present work, both infections H. pylori and G. lamblia coexisted in 75% of epigastric pain cases which could be explained on the basis that both organisms predispose to each other.
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PMID:Impact of helicobacter pylori infection on the activities of urease and lipase enzymes in patients with giardiasis. 1841 Jul 12