Disorders of the Small Bowel and Colon Flashcards
(90 cards)
1
Q
If there’s Chronic Diarrhea, is it likely to be infectious?
A
no
-it’s gonna be something like IBD or something like that
2
Q
What are the most common infectious causes of bloody diarrhea?
A
- salmonella
- shigella
- E. coli (0157 H7)
- Campylobacter
- Yersinia enterocolitica (sometimes)… that one is psuedo appendicits
3
Q
Salmonella Typhi
A
- Gram - enteric bacillus
- fever
- Endotoxin like the rest of gram negative things AND Vi antigen
- Relative bradycardia
- Rose spots
4
Q
What can be a chronic reservoir for Salmonella Typhi?
A
Gallbladder
-healthy asymptomatic carrier
5
Q
What does MEN1 have?
A
- pituitary adenoma*
- parathyroid hyperplasia
- pancreatic tumors
6
Q
What does MEN2a have?
A
- parathyroid hyperplasia
- Medullary thyroid carcinoma
- Pheochromocytoma
7
Q
What doe MEN2b have ?
A
- mucosal neuromas*
- MArfanoid body habitus*
- Medullary thyroid carcinoma
- Pheochromocytoma
8
Q
If the diarrhea is osmotic, what will decrease the stool volume?
A
fasting
-there will be a high osmotic gap
9
Q
If the diarrhea is secretory, what will it be like?
A
- large volume (>1L a day)
- normal osmotic gap
- stool sodium will be high
- little change with fasting
- hyponatremia and nonanion gap metabolic acidosis
- Villous adneoma
- Bile salt malabsorption
10
Q
What should we think if we see fecal calprotectin?
A
IBD
11
Q
What are the most common causes of Chronic diarrhea?
A
- meds
- IBS
- Lactose intolerance
12
Q
What is the stool osmotic gap?
A
difference between measured osmolality of the stool and the estimated stool osmolality
-Normal is <50 mOsm/kg
13
Q
if chromogranin A is positive, what is it?
A
VIPoma
14
Q
If calcitonin is high, what’s up?
A
Medullary thyroid cancer
15
Q
If gastrin is high, what’s up?
A
ZE syndrome
16
Q
If we see fecal calprotectin, what’s up?
A
IBD
17
Q
What do we think of if we see 5-HIAA in the urine?
A
Carcinoid tumor
18
Q
What is IBS?
A
- chronic functional disorder
- Not expleained by the presence of structural or biochemical abnormalities
- Dx: based on the presence of a compatible profile (ROME III)
- it’s idiopathic
19
Q
What is the ROME II criteria for IBS Dx?
A
-abdominal discomfort or pain at least 3 days/month for the past 3 months, with symptom onset>6 months before diagnosis and at least 2/3: relieved with defecation, onset associated with a change in frequency of stool, onset associated with a change in form of stool
20
Q
What is FODMAPS?
A
Fermentable monosaccharides and short chain carbohydrates
-exacerbate bloating, flatulence, and diarrhea in some patients
21
Q
Is high fiber a good thing in IBS patients?
A
“appears to be of little value in helping IBS patients”
22
Q
What do we use to treat C diff?
A
Metronidazole
-harry potter and voldemort
23
Q
What is colitis from antibiotics caused by?
A
C diff
24
Q
What are most cases of antibiotic associated diarrhea from?
A
adverse effects of antibiotics
- NOT c diff
- mild and self limited
25
What two toxins does C diff form?
TcdA (enterotoxin)
| TcdB (cytotoxin)
26
So, what do we need to check if we suspect C diff?
check stool for toxin assay
- flex sig used if atypical symptoms and positive toxins
- CT or Abd Xray if severe or fulminant symptoms to look for megacolon or perforation
27
What antibiotics will we usually see used in a question stem if C diff is cookin?
ampicillin
clindamycin
3rd gen cephalosporins and fluoroquinolones
-hospitalizations
28
What's a weird thing that can happen with fecal impaction?
paradoxical or "overflow" diarrhea
| -the only thing that can get past is liquid
29
How do you treat constipation/fecal impaction?
enemas
digital disruption
-long term- good bowel regimen
30
What is Microscopic colitis?
- idiopathic
- sometimes medications can cause it
- R/o celiac
- chronic or intermittent watery diarrhea
- *normal mucosa on endoscopy
31
How do you treat microscopic colitis?
stop offending medication
| -loperamide, budesonide, bile-slat binding agents, or 5-ASA's
32
What are some risk factors for diverticular disease of the colon?
- old
| - CT disease: Ehlers-Danlos, Marfan syndrome, Scleroderma
33
What is diverticulosis?
- Asymptomatic, Dx on colonoscopy or barium enema
- usually sigmoid and descending colon, can be anywhere in the colon
- symptomatic complications: GI bleed, Diverticulitis
34
What is diverticulitis?
- macroscopic inflammation of diverticulum
- may have microperforation with localized paracolic inflammation
- may have macroperforation with abscess or peritonitis
35
How do you treat Diverticulitis?
- maybe Abx
| - NPO/clear liquid diet
36
What should people with diverticulitis do after symptom resolution?
undergo diagnositc imaging to exclude colonic neoplasms
| -CT with contrast
37
What is the most common type of polyp?
Mucosal adenomatous polyps (70%)
- tubular
- tubulovillous
- villous
38
What do mucosal serrated polyps look like?
- hyperplastic
- sessile serrated polyps
- traditional serrated adenoma
39
What are some mucosal nonneoplastic polyps?
Juvenile
hamartomas
inflammatory
40
What are some submucosal lesions that can happen in the colon?
Lipomas
Lymphoid aggregates
Carcinoids
Pneumatosis cystoides intestinalis
41
What do 95% of cases of Colon adenocarcinoma come from?
Adenomas and serrated polyps
| -high risk of prgressing to malignancy if they are: >1 cm, contain villous features, have high grade dysplasia
42
What will we see in a patient who has asymptomatic colon cancer?
FOBT positive
| Iron deficiency anemia
43
What is the Gold standard for detecting polyps?
Colonoscopy
44
What are potential complications of colonoscopy?
Bleeding and perforation
45
FOBT
```
Fecal occult blood testing
-Guaiac based
-detect pseudoperoxidase activity of heme or hemogloblin
-need predietary restrictions
-
```
46
FIT
```
Fecal immunochemical test
-Tests for hgb
-no predietary restrictions
preferred over FOBT
-more sensitive than Guaiac based tests
-Screening for CRC and advanced adenomas
```
47
Fecal DNA
Tests for stool Hgb
| -measures a variety of mutated genes and methylated gene markers from exfoliated tumor cells
48
Does intussusception happen more in adults or kids?
kids!
| -more common in kids, rare in adults
49
FAP
Familial adenomatous polyposis
- eraly development of a shit ton of polyps and adenocarnicoma
- Extracolonic: dudoenal adenomas, desmoid tumors, osteomas
50
What gene is associates with FAP?
-APC gene (90%) or MUTYH gene mutation
51
Tx of FAP
- prophylactic colectomy (CRC inevitable by age 50)
| - family needs to be testing and genetic counseling
52
Peutz Jeghers Syndrome
- Hamartomatous polyposis syndrom
- auto dominant
- Hamartomatous polyps thorughout GI tract, mostly small intestine
- Mucocutanious pigmented macules on the lips, buccal mucosa, or skin
53
Are Hamartomas malignant?
NO!
54
What kinds of cancer can develop in Peutz Jeghers?
GI malignancy in 40-60%
- Breast CA in 30-50%
- Gonadal or pancreatic CA
55
What gene is there a defect in in Puetz Jeghers?
Threonine kinase II gene
56
Familial Juvenile polyposis
- Hamartomatous polyposis syndrome
- auto dominant
- >10 juvenile hamartomataus polyps (mostly in colon)
57
What genetic defects are in Familial Juvenile polyposis?
Loci on 18q and 10q
| -MADH4 and BMPR I A
58
Cowden disease
- PTEN multiple hamartoma syndrome
- hamartomatous polyps and lipomas throughout the GI tract
- Trichilemmomomas: benign tumor at the root of the hair follicle
- Cerebellar lesions
- Increased rate of malignancy (thyroid, breast, and urogenital tract)
59
Lynch syndrome
- aka: Hereditary nonpolyposis colon cancer (HNPCC)
- autosomal dominant
- Gene mutation: MLH1, MSH2
- increased risk of CRC, endometrial CA, and others at a young age
- Rapid poly transformation benign to malignant in 1-2 years
60
When should we suspect Lynch syndrome?
person early onset CRC
| -FH of CRC, edonmetrial CA, or lynch syndrome
61
Dx of Lynch syndrome?
- Besthesda criteria
- tumor tissue immunohistochemcial staining for mismatch repair proteins
- testing for microsatellite instability
- confirmed by genetic testing
62
Screening for lynch syndrome
- colonoscopy every 1-2 yrs begin age 25, or 5 yrs younger than age of youngest affected family member at diagnosis
- pelvic exam, transvaginal US, and endometrial sampling for Women starting at age 30-35
- upper endoscopy every 2-3 years beginning at age 30-35 to look for gastric cancer
- prophylactic hysterectomy with oophorectomy age 40 or once done childbearing
63
Besthesda Criteria?
- CRC under age 50
- Synchronous CRC or lynch syndrome-associated tumor regardless of age (enometrial, stomach, ovary, pancreas, ureter, renal, biliary, brain)
- CRC with one or more first degree relations with CRC or lynch syndrom erelated cancer with one of the cancers occurring before age 50
- CRC with two or more second degree relative with CRC or LS
- Tumors with infiltrating lymphocytes, mucinous/signet ring differentiation or medullary growth pattern in patients younger than 60 yo
64
Gardner's syndrome
- adenomatous colon polyps
- 95% develop cr polpyps
- Osteomas of mandible, skull and long bones
- supernumerary teeth, epidermoid and sebaceous teeth, thyroid and adrenal tumors. desmoid (fibrous) tumors
- Autosomal dominant
65
Turcot's syndrome
- Adenomatous colon polyps
- brain tumors
- colorectal cancer--100% over 40 years of age
- Auto dominant
66
Pernicious anemia/ Autoimmune Gastritis
- Autoimmune destruction of fundic glands
- loss of them
- achlorhydria... pronounced hypergastrinemia (kinda like ZE)
- induce hyperplasia of gastric enterochromaffin-like cells
- development of small, multicentric carcinoid tumors (5% of patients)
67
in Autoimmune gastritis, what is the result of the loss of fundic glands?
achlorhydria
decreased IF secretion
Vitamin B12 malabsorption
68
Celiac disease
IgA tissue tansglutaminase
- if IgA deficiency, check IgG to deamidated gliadin peptide (anti-DGP)
- Wgt loss, chronic diarrhea, abdominal distention, growth retardation
- Dermatitis herpetiformis, iron deficiency anemia, osteoporosis
69
What part of the GI tract does Celiac disease damage most?
proximal small intestinal mucosa
70
What is the weird gene that is with celiac disease?
HLA-DQ2 or DQ8
71
Whipple disease
- rare multi system disease
- fever, LAD, Arthralgias, Wgt loss, malabsorption, chronic diarrhea
- Encephalitis, ocular abnormalities
72
Dx Whipple disease
Duodenal bx with PAS + periodic acid schiff macrophages with characteristic bacillus
73
What is the characteristic bacillus in Whipple disease?
Tropheryma whippelli
| -gram positive bacilli (not acid fast
74
Tx of whipple disease
Abx
75
Bacterial overgrowth
- distention, flatulence, diarrhea, weight loss
- increased qualitative and quantitative fecal fat
- reduced absorption of B12 and carbs
- need to check serum iron
- osmotic and secretory diarrhea
76
When should we think of bacterial overgrowth?
in the elderly with malabsorption
77
Dx of bacterial overgrowth
Breath tests (hydrogen, methane, glucose, lactulose, or C-xylose)
78
Tx of bacterial overgrowth
Abx duh!
79
Short bowel syndrome
- removal of significant segments of small intestine
| - crohn, volvulus, tumor resection, trauma...
80
Terminal ileum resection
- bile salts and vit B12 malabsorption
- Increased chance of oxylate kidney stones
- Increased chance of cholesterol gallstones
81
how do you treat that B12 malabsorption?
B12 injections, bile salt binding resins, low fat diet, fat soluble vitamin replacements
82
what to do about the oxylate kidney stones in short bowel syndrome?
Give calcium supplementation
83
How much of the proximal jejunum is required to maintain oral nutrition?
at least 200cm
| -if there's no colon and less than 100-200 cm of proximal jejunum, they require parenteral nutrition (TPN)
84
Lacatase deficiency
diarrhea, bloating, flatulence, abdominal pain AFTER ingestion of milk-containing product
- Dx: symptomatic improvement with lactose free diet (confirm by hydrogen breath test)
- Lactase-brush border enzyme hydroyzes disaccharide lactose into glucose and galactose
85
Urea breath test
H. pylori
86
Hydrogen breath test
Lactose intolerance
| -can also do for bacterial overgrowth
87
Glucose, lactulose, or 14C-xylose breath test
-bacterial overgrowth
88
Pernicious anemia
- rare
- AI destruction of gastric fundic glands
- loss of inhibition to gastrin G cells
- may cause hyperplasia of gastric enterochromaffin-like cells (can lead to small carcioid tumors)
- decreased intrinsic factor secretion
- B12 malabsorption
89
What does the histology look like on pernicious anemia?
severe gland atrophy and intestinal metaplasia
90
What is the big risk that was bolded on the pernicious anemia slide?
3 FOLD INCREASED RISK OF GASTRIC ADENOCARCINOMA
