It's All About the Bowels

One more week of classes, then a week off for studying, and then it's our big exam for the semester. I don't know what's worse, having to write 5 exams in potentially completely unrelated subject areas you've covered during the semester or having one exam on everything you've done in the semester. I guess with one exam you get it all done and over with, but what if you have a bad day?

This accumulation of knowledge is really starting to get to me. New information is getting processed but at the same time, older information is being wiped away to make room for the more recent stuff. I'm at that point where I feel like I'm getting this error saying, "Disk full. Please insert a new disk."

I'm all about the mnemonics to remember stuff. Here are few more that I've come across or made up myself during the last few weeks of GI:

SECS causes bloody diarrhea (invasive bacteria)

Salmonella typhi - fecal-oral transmission
Enteroinvasive Escherichia coli - uncooked hamburger and swimming water
Campylobacter (eg. C. jejuni) - uncooked meat, esp poultry
Shigella dysenteriae - fecal-oral transmission


In a severe attack of ulcerative colitis, you get...HEAPS oF feces

Hb < 10 g/dL
ESR > 30 mm/hr
Albumin < 30 g/L
Pulse > 90 bpm
Stools > 6/day with blood
o
Fever > 37.5ºC


DOMES for diarrhea

Dysmotility

• eg. Thyrotoxicosis, IBS
  

Osmotic

• Food ingestion --> increased solute drag --> greater than 500 mL stool/day
• Disappears with fasting
• eg. lactose intolerance, magnesium antacids, gastric surgery

Malabsorption

• Voluminous, bulky, fatty, pale, smelly, floating, difficult to flush stools --> steatorrhea (more than 7 g fat in a 24 hr stool collection)
• eg. Coeliac disease, chronic pancreatitis, previous gastrectomy
  

1. Lipolytic phase defects (eg. pancreatic enzyme deficiency)
   
2. Micellar phase defects (eg. bile salt deficiency)
   
3. Mucosal defects (eg. diseased epithelial lining)
   
4. Delivery phase defects (eg. inability to transport fat from cells to lymphatics)
   

Exudative

• Inflammation of colon --> small volume, frequent, bloody and/or purulent stools
• eg. IBD, colon cancer

Secretory

• High volume, no pus/blood, not excessively fatty, diarrhea that persists when fasting.
• Net secretion > net absorption
• Causes
• Infection (eg. E. coli, S. aureus, Vibrio cholerae)
  
• Hormonal conditions (eg. vasoactive intestinal polypeptide-secreting tumor, Zollinger-Ellison syndrome, carcinoid syndrome)
  
• Villous adenoma
  

Potent Quotables

Pam: "Are you really in charge of picking the health care plan?"
Dwight: "Yes, and my decision is final."
Pam: "This is a ridiculously awful plan because you cut everything."
Dwight: "Awwwwwwww, times are tough Pam. Deal with it."
Jim: "You cut more than you had to didn't you."
Dwight: "Sure"
Jim: "Why did you do that? You work here, don't you want good insurance?"
Dwight: "Don't need it. Never been sick. Perfect immune system."
Jim: "K, well, if you've never been sick, then you don't have any antibodies..."
Dwight: "I don't need them. Superior genes. I'm a Schrute. And superior brain power. Through concentration I can raise and lower my cholesterol at will."
Pam: "Why would you want to raise your cholesterol?"
Dwight: "So I can lower it."

Clubbing Mnemonic

So I think you pretty much look for finger/toe clubbing on examination of any system. Today I was going over some past exams and were we trying to remember some of the causes of clubbing (since there's a ton of them and the mechanisms behind clubbing are not all known). For anyone out there who is looking for a clubbing mnemonic, this one's gold! Got this from a our super awesome 3rd year tutors =) =)

CLUBBING (with ABCDEF for lung diseases)

• C yanotic heart disease
  
• L ung diseases
• A bscess
• B ronchiectasis
• C ystic fibrosis
• D on't say COPD!!!
• E mpyema
• F ibrosis
  
• U lcerative colitis + Crohn's (Inflammatory Bowel Diseases)
• B iliary cirrhosis
  
• B irth defect
  
• I nfective endocarditis
  
• N eoplasm (lung cancer, mesothelioma)
  
• G I malabsorption syndromes (Coeliac disease)