DIGESTIVE DISEASES. Main Characteristics The digestive system is composed of:
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Transcript of DIGESTIVE DISEASES. Main Characteristics The digestive system is composed of:
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