This book describes Intestinal Diseases, Diagnosis and Treatment and Related Diseases

The intestines consist of:

1.Small intestine - 30 feet, help in digestion of food

2.Large intestine - 6 feet, absorbs nutrients from digested food and fluid involved in digestion

Functions of small intestines:

1. Bile salts-500cc from liver.

They are stored in the gallbladder and passed on to the duodenum

Bile salts neutralize the acid and make fatty acid more soluble.

Bile salts from the liver emulsify fats.

It aids full use of proteins and carbohydrates, stimulates the activity of small intestine, convey waste material for excretion.

Cholesterol is also produced from liver and gallbladder.

2. Pancreatic juices have many enzymes digestion of fats, protein and carbohydrates.

3. Intestinal juice from gland in mucosa – water, salt enzyme and activator of enzymes which transforms protein to amino acid and decompose nucleic acid.

Actions:

Neutralization:

Bicarbonate ions from the pancreas and bile from the liver counteract stomach acid to form a pH environment that is appropriate for pancreatic and intestinal enzymes.

Digestion:

Enzymes from the pancreas and the small intestine lining finish the breakdown of food molecules.

Absorption:

The circular folds, villi, and microvilli raise surface area.

Most nutrients are actively or passively absorbed.

Most of the consumed water or the water in digestive tract secretions is absorbed in the intestines.

Mixing and propulsion:

Segmental contractions combine the chyme, and peristaltic contractions transport the chyme into the large intestine.

Excretion:

Bile from the liver contains bilirubin, cholesterol, fats, and fat-soluble hormones.

Protection:

Mucus supplies lubrication, stops the digestion of the intestinal wall and defends the small intestine from stomach acid.

Peyer’s patches defend against microorganisms.

Functions of Large Intestines

1. It serves as a reservoir for the intestinal contents (cecum, ascending colon, rectum).


2. It absorbs water and electrolytes, so the 500–1500 mL of chyme that reaches the large intestine can be reduced to about 100–200 mL.
   
   The large intestine is not an essential organ.
   
   Large segments of the intestine can be excised e.g., for treatment of cancer.
   
   Actions:
   
   Absorption:
   
   The proximal 50% of the colon absorbs salts (e.g., sodium chloride), water, and the vitamins (e.g. Vitamin K) synthesized by bacteria.
   
   Storage:
   
   The distal half of the colon retains feces until it is removed.
   
   Mixing and propulsion:
   
   Slight segmental mixing happens.
   
   Mass movements pushes feces toward the anus and defecation removes the feces.
   
   Protection:
   
   Mucus supplies lubrication; mucus and bicarbonate ions defend against acids produced by bacteria.

Diseases of Intestines:

Most diseases involved the large intestines than small intestines:

1, Intestinal motility disorder (both small and large intestines)

2. Inflammatory Bowel Disorders such as Crohn disease (small intestine) and ulcerative colitis (large intestine)

3. Irritable Bowel syndrome (large intestine)

4. Colorectal polyps, tumor and cancers (large intestine)

5. Diverticular disease of colon (large intestine)

6. Intussusception and volvulus (both small and large intestines)

7. Intestinal infections (both small and large intestines)

8. Intestinal obstruction (both small and large intestines)

9. Intestinal hernias (both small and large intestines)

TABLE OF CONTENT

Introduction

Chapter 1 Intestinal Diseases

Chapter 2 Intestinal Motility Disorder

Chapter 3 Intussusception

Chapter 4 Crohn’s Disease

Chapter 5 Volvulus

Chapter 6 Diverticular Disease

Chapter 7 Irritable Bowel Syndrome

Chapter 8 Colorectal Cancer

Epilogue