Villous atrophy

The small intestine has tiny, finger-like projections called villi that help absorb nutrients from food. Villous atrophy refers to the flattening or shrinking of these villi. When the villi are damaged and shrink, they can no longer effectively absorb nutrients, leading to various health problems.

What causes villous atrophy?

Villous atrophy can be caused by several conditions, including:

1. Celiac disease: This is the most common cause of villous atrophy. Celiac disease is an autoimmune disorder where the body’s immune system attacks the small intestine when gluten (a protein found in wheat, barley, and rye) is consumed.
2. Infections: Certain infections, such as bacteria, viruses, or parasites, can damage the villi and lead to villous atrophy.
   • Bacterial infections: Bacteria such as Salmonella, Campylobacter, and Clostridium difficile can infect the intestines and cause inflammation and damage to the villi.
   • Viral infections: Viruses like rotavirus and norovirus can infect the gastrointestinal tract, leading to inflammation and villous atrophy.
   • Parasitic infections: Parasites like Giardia lamblia and Cryptosporidium can infect the intestines and cause significant damage to the villi.
   • Parasites: Organisms that live on or in a host and get their food from or at the expense of their host.
3. Inflammatory conditions: Conditions that cause inflammation in the small intestine, such as Crohn’s disease, can lead to villous atrophy.
4. Medications: Some medications, including certain nonsteroidal anti-inflammatory drugs (NSAIDs) and chemotherapy agents, can cause villous atrophy as a side effect.

How is villous atrophy different from villous blunting?

While villous atrophy and villous blunting both involve damage to the villi in the small intestine, they differ in the extent and severity of this damage:

• Villous atrophy: Refers to the more severe flattening or complete loss of the villi. The villi may be significantly reduced in size or entirely absent, resulting in a drastically reduced surface area for nutrient absorption. This can lead to more pronounced nutritional deficiencies and related health problems.
• Villous blunting: Refers to the shortening or flattening of the villi. The villi become shorter and lose their elongated shape but are still present. This can reduce the surface area available for nutrient absorption, leading to less efficient nutrient uptake.