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Effects of Deficiency of Exocrine Pancreatic
Secretion
Sajaratul Syifaa’ Binti IbrahimBatch 6
0313887Physiology Seminar ( 16th April 2015)
Products Exocrine Part by of Pancreas
Provide Digestive Enzymes
1. Proteolytic enzymes- Trypsin- Chymotrypsin- Carboxypeptidase
2. Lipid digesting enzymes- Pancreatic lipase- Phospholipase- Cholesterol esterase
3. Pancreatic Amylase
4. Ribonucleases & deoxyribonucleases
Provide Electrolytes
1. Cl- secreted by acinar cells—with small volume of water
2. HCO3- is secreted by ductular
cells–with larger volume of water
Functions of Pancreatic Enzymes• Pancreatic Amylase- The chyme empties from the stomach
- Chyme mixes with the pancreatic amylase
- Carbohydrates → maltose or glucose before passing beyond the duodenum
• Pancreatic Protease‐ The pancreas secretes several proteases (trypsinogen,
chymotrypsinogen and procarboxypeptidase)
‐ Trypsin and chymotrypsin will break down protein → peptides
‐ Carboxypeptidase will split off individual amino acids of peptides
• Lipid Digesting Enzyme‐ Most of triglycerides → monoglycerides & fatty acids by pancreatic
lipase
‐ Cholesterol esterase & phospholipase hydrolyse phospholipids & cholesterol esters → free fatty acids
What is Pancreatic Insufficiency ?
Exocrine Pancreatic Insufficiency (EPI)
Characterized by deficiency of the exocrine pancreatic
enzymes, resulting in the inability to digest and absorb
nutrients from the diet
•MaldigestionImpaired breakdown of nutrients (carbohydrates, protein, fat) to absorbable split-products
•MalabsorptionDefective mucosal uptake and transport of adequately digested nutrients including vitamins and trace elements.
Etiology of Pancreatic Insufficiency
Pancreatitis
- Alcohol drinking- Cystic fibrosis- Gallstones
Pancreatectomy
- Due to pancreatic cancer
- Severe pancreatitis
Overview of Exocrine Pancreatic Insufficiency Symptoms
Exocrine Pancreatic Insufficiency
Steatorrhea
Abdominal Distension
Weight loss
Oedema
Exacerbate motility disorders
Deficiency of vitamin B12
Malabsorption of lipid-soluble vitamins
Diarrhea
Clinical Features of Exocrine Pancreatic Insufficiency
1. Diarrhea - Results from undigested contents settling inside the intestines.- Excessive amounts of solutes tend to retain water inside the intestines
causing diarrhea ( Osmotic Diarrhea )
2. Steatorrhea- Hallmark of malabsorption- Due to excess presence of fat in stools - As a results of deficient amount of pancreatic lipase
3. Malabsorption of lipid-soluble vitaminVitamin Functions DeficiencyA • Components of the visual pigments -
Rhodopsin• Acts as antioxidant to prevent injury to
cellular membrane
• Visions problems• Xeropthalmia - a pathologic
dryness of conjunctiva and cornea
• Skin problems ( scaling skin’ psoriasis and acne)
D • Aids in absorption of calcium and phosphate for bone growth
• Rickets and osteomalacia• Malabsorption lead to secondary
hyperthyroidism
E • Acts as antioxidant which prevents the injury to cellular membrane
• Rarely occur as large amount stored in the adipose tissues
• Neurological disorder may occur
K • Required in the formation of hepatic synthesized blood clotting factors ( II, VII, IX and X) and prothrombin
• Bleeding disorders
4. Abdominal distension‐ Deficiency in pancreatic enzyme secretions lead to poor digestion and
absorption of foods in the duodenum ‐ More undigested food reach the bacteria in the colon‐ The bacteria will react with the undigested contents inside the colons and
cause production of gas
5. Weight loss - Malabsorption cause deficiencies of sugar, fats, proteins and selective
vitamins and minerals. - Lack of nutrients provided to meet the requirements
6. Oedema
Chronic protein malabsorption due
to pancreatic enzyme insufficiency
Decrease the serum albumin
level- Hypoalbuminemia
Loss of protein into the intestinal
lumen
Reduced plasma protein (albumin) in the blood
thus reducing the osmotic pressure- reduces pulling
of fluid into vessels
Enhances retention of fluid in the tissue
space OEDEMA
7. Exacerbate motility disorders
- Exocrine pancreatic insufficiency itself can cause motility disorders. -Maldigestion and malabsorption of lipid and protein may
lead to inability to stimulate the secretion cholecystokinin (CCK) by the I cells of duodenum and jejunum- CCK act as inhibitor of gastric emptying -With the absence of CCK, gastric emptying will be rapid
8 . Deficiency of vitamin B12
‐ When vitamin B12 enters stomach, it binds to Haptocorrin ‐ Haptocorrin and vitamin B12 complex can’t be broken down by
pancreatic enzyme in exocrine pancreatic insufficiency ‐ Vitamin B12 will be unable to bind with intrinsic factors
Megaloblastic Anaemia
- Most pronounced in rapidly dividing cells such as erythropoietic tissue of bone marrow
- Leads to insufficient DNA synthesis in the red blood cell synthesis—vitamin B12
Neurological Manifestations
- Abnormal fatty acids will accumulate and become incorporated into cell membrane including those of the nervous system
Test Confirming Exocrine Pancreatic Insufficiency
1. 72 Hour Fecal Fat Test - Consume diet containing 100 g of fat- For 3-5 days and collect all stool for 72 hours during this period. - Presence of an amount of fat in the stool greater than 7% of the total
amount of fat consumed in the diet during this period is indicative of fat malabsorption
2. 13C-Labelled Mixed Triglyceride Breath Test ( 13C MTG-BT)
• A labelled substrate is given orally together with test meal• After intraduodenal hydrolysis of the substrate by specific pancreatic enzymes, 13C-
marked metabolites are released, absorbed from the gut and metabolized within the liver.
• As a consequence of the hepatic metabolism, 13CO2 is released and thereafter eliminated with the expired air
The amount of 13CO2 expired, which indirectlyreflects the exocrine pancreatic function, can be measured by means of mass spectrometry or infrared analysis
References• Textbook of Medical Physiology, Guyton and Hall ( 11th Edition) Page : 799-802• Textbook of gastroenterology, Tadataka Yamada ( 5th Edition) Page : • Journal of Gastroenterology and Hepatology : Pancreatic exocrine
insufficiency: Diagnosis and Treatment by Enrique Domínguez-Muñoz• http://www.merckmanuals.com/professional/gastrointestinal-disorders/mala
bsorption-syndromes/overview-of-malabsorption• http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3132852/pdf/ceg-4-055.pdf• http://www.everydayhealth.com/health-report/exocrine-pancreatic-insufficie
ncy/know-the-symptoms-of-epi.aspx• http://emedicine.medscape.com/article/2121028-clinical
Questions • What kind of diet that should be taken for pancreatic insufficient patient
1. Low fat diet as fat is more complex to be digested and it can’t be compensated if there is insufficiency. With taking low fat diet, steatorrhea incidence can be reduced.
2. Include whole grains in your diet as it can bulk up the fatty stool which is the results of malabsorption of fat
3. Milk or any sources of calcium as in exocrine pancreatic insufficiency, patients are not able to absorb calcium due to deficient vitamin D absorption.