Final answer:
Villous atrophy in the small intestine leads to malabsorption of nutrients, causing symptoms such as diarrhea, weight loss, anemia, and fatigue in patients with celiac disease.
Step-by-step explanation:
The signs and symptoms experienced by patients with celiac disease are a result of villous atrophy in the small intestine. The villi are finger-like projections that line the small intestine and increase its surface area for absorption of nutrients. When the villi in the small intestine atrophy due to the autoimmune reaction caused by celiac disease, the surface area available for nutrient absorption is significantly reduced. This leads to malabsorption and deficiencies in essential nutrients, such as carbohydrates, fats, proteins, vitamins, and minerals.
The lack of nutrient absorption can result in diarrhea, weight loss, anemia, and fatigue. Diarrhea occurs because the undigested nutrients and excess water pass through the intestine quickly. Weight loss is a consequence of the body not receiving enough nutrients. Anemia may develop due to the insufficient absorption of iron, which is necessary for the production of red blood cells. Fatigue can be attributed to the overall imbalance and deficiency of essential nutrients in the body.