retinol-palmitate and Malabsorption-Syndromes

Malabsorptive etiologies of chronic diarrhea are important to identify. The 72-h stool for fecal fat test (FFT), the gold standard for diagnosing fat malabsorption, is fraught with limitations that impact its reliability. Vitamin A, a fat-soluble vitamin, parallels the absorption of lipids. We assessed the feasibility and validate a novel clinical test, retinyl palmitate (RP), for the diagnosis of fat malabsorption, and to compare the results to the FFT.. Using a case-control study design, patients with chronic diarrhea secondary to suspected malabsorption, and healthy control subjects were identified. A Dietitian taught subjects to consume a 100g fat diet for the FFT with measurements of stool fat after 72-h. Serum levels of Vitamin A (retinol) and RP were measured by reversed-phase high pressure liquid chomatography. Two-way comparisons were made between the groups using 2 sample Wilcoxon rank-sum tests.. Sixteen patients completed this study (8 cases and 8 control subjects). Fecal fat results were available for 15/16 patients. The sensitivity of the FFT was 100% (identified all cases), but the FFT specificity was 42%, as 4/7 control patients were identified as malabsorbers. Cases with short bowel syndrome had the lowest RP levels but this did not meet statistical significance. There was no significant difference for serum RP levels when comparing cases and control patients' AUC.. Serum RP is useful to identify malabsorption, albeit in severe cases. Furthermore, we have shown that the 72-hour FFT has poor performance characteristics, highlighting the need for more useful diagnostics in identifying malabsorption.

Topics: Adult; Case-Control Studies; Chromatography, High Pressure Liquid; Diarrhea; Dietary Fats; Diterpenes; Female; Humans; Malabsorption Syndromes; Male; Middle Aged; Retinyl Esters; Vitamin A

Topics: Alcoholism; Conjunctival Diseases; Corneal Diseases; Diterpenes; Humans; Injections, Intramuscular; Liver Function Tests; Malabsorption Syndromes; Male; Middle Aged; Retinyl Esters; Tomography, X-Ray Computed; Vitamin A; Vitamin A Deficiency

Cryptosporidium parvum is recognized as one of the most important pathogens causing enteritis and severe diarrhoea in calves up to 1 month of age. Although the infection may be responsible for some mortality, its impact is mainly associated with the impairment of intestinal functions and lower performance of animals. The aim of this study was to determine the effect of cryptosporidiosis on the intestinal functions in neonatal experimentally infected Holstein calves. Absorption tests with d-xylose and retinyl-palmitate, and the lactulose/mannitol test of intestinal permeability were simultaneously performed in 1-week intervals from challenge to full recovery. In infected animals, reduced intestinal absorptive capacity for both D-xylose and retinyl-palmitate was observed on day 7 post-infection (p.i.). At the same time, a more than 100% elevation of intestinal permeability was observed in the infected calves. All intestinal functions, except absorption of retinyl-palmitate, were significantly affected and changes were detected up to day 14 p.i. In contrast, results of all tests obtained on day 21 p.i. suggest full recovery of the infected intestine. Significantly, growth of the calves which had recovered from cryptosporidiosis was still affected between days 14 and 21 p.i.

Topics: Animals; Animals, Newborn; Area Under Curve; Cattle; Cattle Diseases; Cryptosporidiosis; Cryptosporidium parvum; Diterpenes; Intestinal Absorption; Intestine, Small; Malabsorption Syndromes; Male; Permeability; Retinyl Esters; Time Factors; Vitamin A; Xylose

Essential fatty acid (EFA) deficiency induces fat malabsorption, but the pathophysiological mechanism is unknown. Bile salts (BS) and EFA-rich biliary phospholipids affect dietary fat solubilization and chylomicron formation, respectively. We investigated whether altered biliary BS and/or phospholipid secretion mediate EFA deficiency-induced fat malabsorption in mice. Free virus breed (FVB) mice received EFA-containing (EFA(+)) or EFA-deficient (EFA(-)) chow for 8 wk. Subsequently, fat absorption, bile flow, and bile composition were determined. Identical dietary experiments were performed in multidrug resistance gene-2-deficient [Mdr2((-/-))] mice, secreting phospholipid-free bile. After 8 wk, EFA(-)-fed wild-type [Mdr2((+/+))] and Mdr2((-/-)) mice were markedly EFA deficient [plasma triene (20:3n-9)-to-tetraene (20:4n-6) ratio >0.2]. Fat absorption decreased (70.1 +/- 4.2 vs. 99.1 +/- 0.3%, P < 0.001), but bile flow and biliary BS secretion increased in EFA(-) mice compared with EFA(+) controls (4.87 +/- 0.36 vs. 2.87 +/- 0.29 microl x min(-1) x 100 g body wt(-1), P < 0.001, and 252 +/- 30 vs. 145 +/- 20 nmol x min(-1) x 100 g body wt(-1), P < 0.001, respectively). BS composition was similar in EFA(+)- and EFA(-)-fed mice. Similar to EFA(-) Mdr2((+/+)) mice, EFA(-) Mdr2((-/-)) mice developed fat malabsorption associated with twofold increase in bile flow and BS secretion. Fat malabsorption in EFA(-) mice is not due to impaired biliary BS or phospholipid secretion. We hypothesize that EFA deficiency affects intracellular processing of dietary fat by enterocytes.

Topics: Animals; ATP Binding Cassette Transporter, Subfamily B; ATP-Binding Cassette Transporters; Bile; Bile Acids and Salts; Body Weight; Carbon Radioisotopes; Cholestanetriol 26-Monooxygenase; Cholesterol 7-alpha-Hydroxylase; Cytochrome P-450 Enzyme System; Dietary Fats; Diterpenes; Enterocytes; Fatty Acids; Fatty Acids, Essential; Homozygote; Kinetics; Liver; Malabsorption Syndromes; Mice; Mice, Knockout; Oleic Acid; Phospholipids; Polyethylene Glycols; Retinyl Esters; RNA, Messenger; Steroid Hydroxylases; Triolein; Tritium; Vitamin A

We treated two infants with failure to thrive who presented with clinical evidence of conjunctival and corneal xerosis. One patient was referred with possible infectious corneal ulcer thought to exist because there were deep peripheral ulcerations of the cornea and associated hypopyon. The other patient was initially thought to have a nasolacrimal duct obstruction because of excessive tearing. Xerophthalmia secondary to vitamin A deficiency was suspected and led to the diagnosis and treatment of cystic fibrosis in each case. Therapy with vitamin A promptly resolved the xerosis, but it also caused a transient rise in intracerebral pressure. Xerophthalmia can still be a problem in developed countries when underlying disorders, such as cystic fibrosis, lead to vitamin A malabsorption.

Topics: Cystic Fibrosis; Diterpenes; Female; Humans; Infant; Malabsorption Syndromes; Male; Retinyl Esters; Vitamin A; Vitamin A Deficiency; Xerophthalmia