Assessment 2 Flashcards
Intestinal reserve: enzymes
Brush border AND pancreatic oligosaccharides/proteinases
Intestinal reserve: pancreas
Pancreas secretes and excess of enzymes
Intestinal reserve malabsorbed nutrients
Transit slowed if malabsorbed nutrients reach distal portion of GI tract
Colon scavenges malabsorbed carbs as SCFA
Malabsorption clinical presentation
Weight loss/fatigue
Excess calorie intake with no weight gain
Excess flatulence/distension
Diarrhea: oily or liquid
Vit/mineral deficiency
Watery diarrhea comes from
Carbohydrate osmotic effect
Oily diarrhea comes from
Fat malabsorption
Diarrhea can come from
Osmotically active molecules reach colon
Malabsorbed molecules stimulate colon/ion secretion –> osmotic gradient
Diagnostic confirmation of malabsorption
Low beta carotene, cholesterol, TG, Ca
Elevated PT
Evidence of mucosal disease
Low albumin, folate, B12, iron
Malabsorption stool tests
Quantitative fecal collection
Steatocrit: >31% = abnormal
72 hr fecal fat test
100g input, measure output
> 7 = malabsroption
Lactase deficiency
Lactase enzyme not in brush border, lactase buildup in lumen –> osmotic diarrhea
Lactose malabsorption and symptoms
6-20g malabsorbed = flatus
> 20g malabsorbed = flatus+diarrhea
Cystic Fibrosis and pancreas
75% of CF patients have pancreatic exocrine insufficiency by 6 months
60% of remaining patients develop PEI by young adulthood
10% retain pancreatic sufficiency
Chronic pancreatitis
Long term alcohol abuse
Destruction of ducts/acini
Reduction of digestive enzymes
ERCP
Detect ductal abnormalities
MRCP
Detect ductal/parenchymal abnormalities
EUS
Detect ductal/parenchymal abnormalities
Tissue sampling
D-xylose test
Old test - directly asses mucosal function of sugar absorption
Celiac sprue
Immune mediated destruction of enterocytes in response to gluten
Small intestinal villi destroyed
Mature digesting/transporting enterocytes absent
Digestion AND absorption imapired
Celiac sprue antibody
IgA to transglutaminase, endomysium, gliadin
Deaminated gliadin petides
Celiac visual presentation
Decreased folds, scalloping mosaic pattern
Celiac histology stages
Stage 1: inflammation
Stage 2: Deep crypts
Stage 3: Villi/enterocytes destroyed
Clinical manifestation of celiac
Weight loss Bulky/oily stools Flatus/frothy stools Anemia Bone disease Edema/hypoproteinemia Vit B deficiency
Bacterial overgrowth
Deconjugation of bile acids by bacterial enzymes
Consumption of nutrients by bacteria
Damage to enterocytes
Bacterial overgrowth diagnosis
Small bowel culture
Lactulose/glucose hydrogen breath test
Anitbiotic response
Terminal ileum resection and malabsorption
Less than 100cm gone: Excess bile salts in colon = watery diarrhea
100cm gone: Liver cant keep up with bile salt loss = steatorrhea
Fat soluble vitamin absorption
Bile salt defecits > mucosal/pancreatic disease
Folate deficiency
Proximal small bowel disease, alcohol, drugs, congenital effect
Protective mechanisms in pancreas
Synthesis of enzymes as inactive zymogens
Trypsin inhibitor in zymogen granule
Segregation of enzymes
Enterokinase restricted to SI
Acute pancreatitis
Acute inflammatroy condition w/ abdominal pain and increase in pancreatic enzymes
Interstitial (mild): Complete recovery
Necrotizing (severe): Permanent damage
Major etiologies of acute pancreatitis
Alcoholism
Biliary
Idiopathic
Other
Pancreatic divisum
Failure of dorsal and ventral pancreas to fuse
Time course of enzyme elevation - acute pancreatitis
Enzymes 3x UL
Lipase increases faster and to higher degree than amylase, takes longer to decrease
Risk factors of severity
Age Obesity 1st or 2nd episode Organ failure at admission Short interval to admission Pleural effusion CT scan-grade D/E
Diagnostic indicators of acute pancreatitis
Tachycardia/hypotension Tachypnea, hypoxemis Hemoconcentration Oliguria Encephalopathy
Local complications of acute pancreatitis
Fluid collection Necrosis Ascites Erosion into adjacent structures GI obstruction Hemorrhage
Systemic complications of acute pancreatitis
Pulmonary
Renal
CNS
Multiorgan failure
Metabolic complications of acute pancreatitis
Hypocalcemia
Hyperglycemia
Chronic pancreatitis
Pain
Calcification
Pancreatic insufficiency
Etiologies of chronic pancreatits
Alcoholism
Idiopathy
Other - CF, hereditary pancreatitis, hypertriglyceridemia, autoimmune, fibrocalcific
Treatment of chronic pancreatitis
Medical therapy: low fat diet, pain control, pancreatic enzyme supplementation
Surgical therapy
-ERCP, Decompression surgery, resective surgery
Pancreatic cancer and pancreatitis
Increase risk of neoplasm in chronic pancreatitis
May present as acute pancreatitis
Poor prognosis
Cystic neoplasm
No prior pancreatitis
Unexplained pancreatitis with cystic lesion
Fluid analysis, endoscopic US, resection
Inflammatory bowel Disease types
Ulcerative Colitis
Crohns
Ulcerative colitis clinical presentation
BLOODY DIARRHEA Fever Cramping/abdominal pain Weight loss Tenesmus General malaise
Ulcerative colitis location
Mainly distal, 95% rectal involvement
15-25% pan colitis - more likely in children
Crohns disease location
Mainly proximal
40% SI
30% Ileocolonic
30% colon only
Endoscopic chrons appearance
Cobblestone mucoas
Inflammatory polyps
Skip lesions
Crohns clinical presentation
Diarrhea Abdominal pain Bleeding Pyrexia Fistulae Perianal disease More mucus than ulcerative colitis
Age and incidence of IBD
Incidence spike in 20s/30s and again in older age for UC
Differences between UC and Crohns
UC: More malaise, diarrhea, and BLOOD
Crohns: More pain, mucus, pus
Etiology of IBD
Genetic ENVIRONMENT Smoking Dietary Infection/bacteria/gut flora
Indications for surgery (IBD)
Perforation Toxic dilation Massive hemorrhage Chronic ill health Cancer risk
Pharmacological treatments
5ASA
Corticosteroids
Immunosuppressants
Anti TNFa
Anti Adhesion molecules
5ASA targets
Leukotrienes and prostaglandins
Corticosteroid immune system target
trafficking, proliferation, t cell regulation
Intestinal complications of Crohnss
Fistulae Abscesses Adhesions Strictures Obstruction
Systemic complications of Crohns
Arthritis
gallstones
Malabsorption: Lactase/B12
Renal stone
Intestinal complications of UC
Fibrosis Shortening of colon Bleeding Stricture Bowel perforation Toxic megacolon
Systemic complications of UC
Arthritis
Uveitis
Classification of laxatives
Hydrophilic
Stimulant
Secretory
Hydrophilic types
Bulk forming
Lubricants
Hyperosmotics
Hydrophilic intervention
Hydrophilic –> increase water content of stool
Increase stool mass = increase peristalsis
Dietary fiber
Pysllium: Metamucil/konsyl
Methylcellulose
Bulk forming drugs
Psyllium: Metamucil/Konsyl
Methylcellulose: Citrucel
Lubricants
Stool softeners
Ducosate Sodium: Colace
Ducosate Calcium: Surfak
Mineral oil - highly effective but incontinence
Osmotic laxatives
Non absorbable hypertonic ions/agents = increase osmotic gradient
Magnesium salts: milk of magnesia, epsom salt, magnesium citrate
Lactulose - Cephulac
Polyethylene glycol: Golytely, Colyte, Miralax
Stimulant laxatives
Stimulate secretion/peristalsis
Rapid onset
Simulant laxative examples
Phenolphthalein
Bisacodyl (Dulcolax)
Sodum phosphate
Neostigmine - stimulates peristalsis
Lubiprostone
Chloride channel activator
Methylnaltrexone
Opioid receptor antagonist
Does not cross BBB
Glycerin suppositories
Hyperosmotic laxative - draws water into lumen at end of intestine
Very quick
Diarrhea drugs - opioid agonist
Decrease peristalsis
Constipation/dependence
Loperamide
Diarrhea drugs - anti muscarinic
Decrease peristalsis
Anti spasmodic
low doses so no atropine like side effects
Diarrhea drugs - aomatostatin analog
Octreotide
Inhibits secretion
Inhibits gastrin release
Decrease SM contraction
Short half life = frequent dosing = impractical for long term use
Diarrhea drugs - bulk forming agents
Psyllium
Methylcellulose
Aminosalicylates
IBD
Administered as pro drugs, digested by gut bacteria to produce active 5ASA
Can result in toxic byproducts: Sulfapyridine
Corticosteroids
Rectal: hydrocortisone - rapid onset
Oral: Prednisone, methylprednisolone - first pass metabolic steroids
Limit long term use
Immunosuppressive drugs
Azathioprine, 6mercaptopurine
Purine biosynthesis inhibitor
Risk of infection
Methotrexate
Immunosuppressive IBD drug
Folate antagonist
Hepatotoxicity, alopecia, myelosuppression, infection
Cyclosporin
Cyclic polypeptide immunosuppressant
Many toxicities, infection
IBD Biologicals
TNF-1 inhibitor: Infliximab, adalimumab
Natalizumab
Humanized MAB that antagonizes integrin heterodimers
Use for UC patients that dont respond ot other treatment
Diverticula
Sac like protrusion of colonic wall
Diverticulosis
Having diverticulum
80% asymptomatic
Diverticluosis epidemiology
Increases with age
Varies geographically
Risk factors
Inverse relation with fiber
High fat/red meat
Pathophysiology of diverticulosis
Erostion of diverticular wall caused by increased intraluminal pressure
Clinical presentation of diverticulitis
LLQ abdominal pain
Change in bowel habits
Urinary symptoms- dysuria/frequency
Diagnostic tests for diverticulitis
Check white count/urinalysis
Ab CT is best/most sensitivity
Complicated diverticulitis (3 types)
Abscess
Fistula
Obstruction
Abscess diverticulitis
Seen on CT
Patients wont be responding to treatment