Oh Poop

Question 1

Hirshsprung

Answer 1

symptoms: very constipated, normal bowel sounds,
cause: neural crest cells fail to migrate to the distal colon -> internal anal sphincter fails to relax to allow defecation
dx: absense of Ach ganglion cells in rectum

Question 2

inflammatory bowel disease

Answer 2

tx: sulfasalazine (most side effects)

Question 3

hepatic encephalopathy

Answer 3

symptoms: irritability, vomiting, cerebral edema and finally coma which leads to death
cause: increase in blood ammonia, Colonic bacteria generate ammonia from fecal urea, which is quickly absorbed into the portal circulation, taken to the liver, where it is detoxified. In patients with liver dysfunction (e.g. alcoholic cirrhosis), the ammonia cannot be detoxified in the liver and instead enters the systemic circulation to cause hyperammonemia

Gastrointestinal bleeding is the single most important precipitating event of hepatic encephalopathy. The proteins in the blood are converted to urea, and intestinal bacteria generate ammonia from the urea.

tx: lactulose, patients with severe liver disease cannot detoxify ammonia coming from the colon, where it is produced by bacterial metabolism of fecal urea; the drop in pH caused by lactulose “traps” ammonia by converting it to NH4+. The effect of lactulose and sorbitol may take 1-2 days.

Question 4

Ulcerative colitis

Answer 4

symptoms: characteristic ulcers, chronic diarrhea mixed with blood. The disease starts at the rectum and progresses proximally. Inflammation is contiguous
cause: inflammatory bowel disease which affects the colon
dx: the inflammation is superficial and does not involve the entire thickness of the colon wall. Autoreactive T lymphocytes are implicated in the disease

Question 5

Crohn’s disease

Answer 5

symptoms: skip lesions throughout the small bowel and colon (patches of inflammation separated by normal mucosa), nausea and vomiting, secondary to obstruction due to fibrosing disease, stricture, or abscess
dx: Inflammation extends through all the layers of the GI tract

Question 6

lactase deficiency

Answer 6

symptoms: osmotic diarrhea
cause: lactose is poorly absorbed, draws water into the colon and causes osmotic diarrhea.The stool osmotic gap will be increased.

Question 7

Irritable bowel syndrome

Answer 7

symptoms: abdominal pain associated with change in bowel habits and relieved by defecation, or accompanied by abdominal distention or bloating, without organic cause