A 70 kg adult develops watery diarrhea and loses approximately 2.0 liters of fluid stool over 24 hours. Estimate the percent of total body water lost and categorize the likely severity of dehydration using total body water = 60% of body weight and clinical thresholds: <5% mild, 5–10% moderate, >10% severe.

Which rationale best explains how colonoscopy with polypectomy reduces colorectal cancer incidence and mortality?

A patient reports recurrent abdominal cramping, bloating, and alternating diarrhea and constipation for 8 months; stool studies are normal and colonoscopy 2 years ago was unremarkable. Which analytic conclusion best supports an IBS diagnosis and which feature argues against it?

Which statement best defines the clinical distinction between occasional heartburn and gastroesophageal reflux disease (GERD)?

Which sequence best summarizes the pathogenic mechanism by which celiac disease causes malabsorption after gluten exposure?

A patient with nightly reflux asks which nonpharmacologic strategy is mechanistically most likely to reduce nocturnal GERD episodes. Which option best explains the mechanism?

Which physiologic change in the large intestine primarily explains constipation?

Which symptom should prompt immediate clinical evaluation for possible colorectal pathology rather than routine reassurance?

Design a one-day meal plan outline targeted to increase soluble and insoluble fiber intake for a patient aiming to go from 10 g/day to ~30 g/day, listing specific foods and approximate fiber contributions that demonstrate application of fiber mechanisms.

A child presents with chronic failure to thrive and steatorrhea. Biopsy of the proximal small intestine shows flattened villi and crypt hyperplasia. Using anatomical and physiological knowledge, which diagnosis and primary consequence best explain these findings?