GI other (cancer, nutrition, allergies/sensitivites, etc)

Question 1

Colon Cancer

Answer 1

2nd leading cause of cancer-related. death in the US for both men & women

>½ of cases could be prevented by regular colonoscopy screening

• Age > 50
• Known causes:
  
  • genetic mutations
    
    • lynch syndrome = most common cause of familial colorectal cancer, mostly GI and GU problems associated with this syndrome
    • familial adenomatous polyposis (must get resection due to 100% chance of recurrence)
• Risks:
  
  • diet:
    
    • high in red meats & processed meats
  • Inflammatory bowel Disease (Crohn’s & ulcerative colitis)
  • decreased physical activity
  • obesity, smoking, alcohol use
• Screening:
  
  • At age 45, both men & women should begin regular screening and have on of the screening tests listed:
    
    • tests that find both polyps & cancer:
      
      • colonoscopy q 10 years or double contrast barium enema q 5 years or
      • CT colonography q 5 years
    • tests that find mainly cancer:
      
      • guaiac-based fecal occult blood test (gFOBT) vs
      • FIT stool DNA test q 3 years (cologard)
        
        • checks for blood in stool & variations of DNA in stool

Question 2

When to screen for colon cancer?

Answer 2

• everyone at age 45
• if you have a 1st degree relative with colon cancer →
  
  • you need to have a screening 10 yrs prior to their diagnosis or at age 40, whichever comes first
    
    • so if father diagnosed at 40, son gets colonoscopy at age 30
• Ulcerative colitis?
  
  • annual colonoscopy q year starting 10 years after initial diagnosis

Question 3

Anatomy of the Small & Large Bowel

Answer 3

Question 4

Vitamin B-12 (cobalamin) deficiency

Answer 4

• function: factor in DNA & RBC synthesis
• Sources:
  
  • mainly animal in origin
• Etiology:
  
  • decreased absorption →
    
    • pernicious anemia, Crohn’s disease, metformin
  • Takes 3-5 years to deplete B12 stores
  • decreased intake
    
    • vegans
• Risks:
  
  • liver disease, gastric bypass, long-term care residents
• S/sxs:
  
  • anemia sxs
  • heme: fatigue, exercise intolerance, pallor
  • epithelial: glossitis, diarrhea, malabsorption
  • neurologic: symmetric paresthesia, spinal cord demyelination, loss of vibratory sense
• Dx:
  
  • CBC: Macrocytic anemia
• Tx:
  
  • B12 replacement: oral, SL, IM, SQ
  • pernicious anemia: lifelong monthly IM therapy
    *

Question 5

Fat malabsorption

Answer 5

• S/sxs:
  
  • steatorrhea (oily diarrhea → yellow, floats to the top)
    *

Question 6

Protein & Carbohydrate Malabsorption

Answer 6

• S/sxs:
  
  • edema (due to protein loss)
  • weight loss & muscle wasting (due to decreased carbs)

Question 7

Tropical Sprue

Answer 7

occurs almost exclusively in the tropics & the cause is unknown

• Pathophys:
  
  • structural damage to the small intestine after bacterial overgrowth
    
    • (Most common = klebsiella, E.coli, Enterobacter) → Chronic diarrhea → malabsorption of B12 & folate
• S/sxs:
  
  • diarrhea/steatorrhea
  • abd cramping, gas
  • hyperactive bowel sounds + sxs of malabsorption
• Dx:
  
  • folate deficiency → megaloblastic anemia, pancytopenia
  • Dx of exclusion:
    
    • r/o other dz with stool cx, O&P (ova & parasites), endoscopy
• Tx:
  
  • Tetracycline + folate +/- vit b12 injections x 3-6 months

Question 8

Hiatal Hernia Type 1 vs Type II

Answer 8

• Most common cause of HERD
  
  • most are asymptomatic and tx isnt necessary
    
    • symptomatic should be treated for GERD
• Dx (for both):
  
  • barium swallow, endoscopy, manometry
• Type I “Sliding Hernia” = most common
  
  • GE junction slides above the diaphragm
    
    • stomach remains below
• Type II “Paraesophageal hernia”:
  
  • as the hernia grows the GEJ stays in place while the greater curvature of the stomach rolls up into the thorax through the diaphragm
    
    • often require surgery:
      
      • due to complications such as volvulus

Question 9

BMI ranges

Answer 9

• <18.5: underweight
• 18.5-25: normal
• 25-29.9: overweight
• 30-39.9: obese
• 40+: morbidly obese

Question 10

Types of hernias in the abdomen

Answer 10

Question 11

Indirect Inguinal Hernia

Answer 11

• Most Common): Passage of intestine through the internal inguinal ring down the inguinal canal, may pass into the scrotum. Often congenital and will present before age one.
• Remember: Indirect goes through the Internal Inguinal Ring (an “I” for an “I”)

Question 12

Direct Inguinal Hernia

Answer 12

Passage of intestine through the external inguinal ring at Hesselbach triangle, rarely enters the scrotum

Question 13

Ventral Hernia

Answer 13

Often from previous abdominal surgery, obesity. Abdominal mass noted at site of previous incision

Question 14

Umbilical Hernia

Answer 14

Very common, generally is congenital and appears at birth. Many umbilical hernias resolve on their own and rarely require intervention. Refer to surgery if an umbilical hernia persists >2 years of life.