DIGESTIVE DISEASES

Main Characteristics

The digestive system is composed of:

Peptic Ulcers

Fig 1. From: http://digestive.niddk.nih.gov/ddiseases/pubs/hpylori/#5

Fig. 1. Fig. 2.

Peptic Ulcers

Ulcer- sore or lesion that forms in the lining of the stomach or duodenum where acid & pepsin are present

Ulcers in the stomach and duodenum are usually classified as peptic ulcers

Peptic Ulcers

Ulcers in the stomach Gastric or stomach ulcers

Ulcers in duodenum Duodenal ulcers

Common Ulcer Symptoms

Most common: gnawing or burning pain in the abdomen between the breastbone and navel

Pain often occurs when stomach is empty: between meals & early morning

May last from a few minutes to a few hours

May be briefly relieved by eating or by taking antacids

Other less common: nausea & vomiting, loss of appetite, weight loss, bloating and burping

Other Ulcer Symptoms

Emergency symptoms:

Bleeding in stomach & duodenum If bleeding is heavy, blood will appear in vomit

or stool

Sharp, sudden, persistent, stomach pain

May feel tired & week

Peptic Ulcer Epidemiology

Before 20th century, peptic ulcers were rare1

About 20 million Americans develop at least one ulcer during their lifetime

Peptic ulcer disease (PUD) is a common illness that affects >6 million persons in the United States each year2

A total of 1,453,892 first-listed PUD hospitalizations were estimated for 1998–2005

1. Majumdar D, Bebb J, Atherton J. Helicobacter infection and peptic ulcers. Medicine. 2010;30:3. 2. Sandler RS, Everhart JE, Donowitz M, Adams E, Cronin K, Goodman C, The burden of selected digestive diseases in the United States. Gastroenterology. 2002;122:1500–11. DOIPubMed

Peptic Ulcer Epidemiology

Hospitalization rates were higher for adults ≥ 65 years of age and decreased with decreasing age group

Ulcers are rare in teenagers, more uncommon in children

Duodenal ulcers usually first occur between ages of 30-50 yrs. of age

Also occur more frequently in men than women

Peptic Ulcer Theories

For almost a century: believed that ulcers were caused by lifestyle factors (e.g. stress, diet)

Later, discovered that ulcers were caused by imbalance between digestive fluids (HCl & pepsin) & stomach’s ability to defend itself against these

Current: Helicobacter pylori infection as the causative agent, non-steroidal anti-inflammatory drugs (NSAIDs), including aspirin and Ibuprofen

Lifestyle, acid & pepsin production play some role but not primary cause of most ulcers.

Helicobacter pylori Infections Spiral shaped stomach bacterium Bacteria + acid secretion damages

stomach, duodenal tissue Causes inflammation (gastritis) & ulcers

H. Pylori can survive in acidic stomach because it produces urease enzyme Urease generates substances that

neutralize the stomach’s acid

Helicobacter pylori Infection

H. pylori H. Pylori in stomach

1. How H. pylori produces ulcers

Bacteria can penetrate stomach’s protective mucous lining because of shape & way they move

They produce substances the weaken stomach’s protective mucus & make the stomach cells more susceptible to the damage of acid & pepsin

2. How H. pylori produces ulcers

Bacteria can also attach to stomach cells further weakening the stomach’s defensive mechanisms & producing local inflammation

H. pylori can also stimulate the stomach to produce more acid (not understood why)

3. How H. pylori produces ulcers

Excess stomach acid & other irritating factors can cause inflammation of the duodenal bulb

In summary H. pylori induces gastritis through production of a variety of antigens, virulence factors, & soluble mediators

The bacterium deregulates, disarms & evades host immune responses to maintain chronic colonization of the gastric mucose

H. Pylori infection

Within weeks of infection with H. pylori, many develop gastritis (inflammation of stomach lining)

However, most will never experience severe symptoms or problem related to the infection

Unclear why some people do and others do not develop H. pylori related symptoms or ulcers

Lifestyle Factors Implicated in Ulcers

Cigarettes Increase ulcer risk, slow rate of ulcer healing

Caffeine Foods Can stimulate stomach acid secretion & aggravate

ulcer pain

Alcohol Consumption Ulcers more common in people with cirrhosis of liver

Emotional Stress No longer thought to be cause of peptic ulcers, but

emotional stress reported to increase ulcer pain

Nonsteroidal anti-inflammatory drugs (NSAIDs)

Prescription of NSAID’s (arthritis treatment)

Non-prescription NSAID- aspirin, ibuprofen & naproxen

Interfere with stomach’s ability to produce mucus & bicarbonate

Affect blood flow to the stomach & cell repair

Ulcers usually disappear once person stops taking drug

Diagnosis

Endoscopic Exams X-ray examinations Testing for H. pylori in blood, breath, &

tissue samples

Treatment

With medicines H-2 blockers Acid pump inhibitors Mucosal protective agents In H. pylori, these meds used in combination with

antibiotics Lifestyle changes

MDs used to advise avoidance of spicy, fatty, or acidic foods

Surgery Usually last result if people don’t respond to meds or

develop complications