Schilling's test is false + ve in (PGI June 2008)

Ans. B (Renal insufficiency) D-Xylose TestPositive TestDecreased D-Xylose excretion in urine due to malabsorption from gastrointestinal mucosal diseaseCauses IncludeCeliac diseaseTropical sprueWhipple's diseaseAnother mucosal diseaseFalse Positive TestDecreased D-Xylose excretion in urine due to causes other than malabsorption from small bowel mucosal diseaseCauses Include# Bacterial overgrowth# Renal insufficiency# Delay gastric emptying# Rapid intestinal transit# Vomiting# Ascites / Pleural effusion (Third space collections) o causes other than malabsorption from small bowel mucosal diseaseTable (Harrison) : Results of Diagnostic Studies in Different Causes of Steatorrhoea. D-XyloseTestSchilling TestDuodenalMucosalBiopsyChronic pancreatitisnormal50% abnormal; if abnormal, normal with pancreatic enzymes1NormalQBacterial overgrowth syndromeNormal or only modestly abnormalQOften abnormal; if abnormal, normal after antibioticsUsuallynormalIleal diseasenormalAbnormal5NormalCeliac sprueDecreasedNormalAbnormal: probably 'flat"QIntestinal lymphangiectasiaNormalNormalAbnormal:"dilatedlymphaticsSchilling Test Resultsnormal.Patient ConditionStage I WaterStage II Intrinsic FactorStage III AntibioticStage IV Pancreatic ExtractHealthynormal.mmPerniciousanemiaLowNormaQ- Bacterial overgrowthLowLowNormal-Pancreatic insufficiencyQ LowLowLowQNormalDefect in ileumQLowLowLowLow