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Flashcards in Constipation and Diarrhea Deck (40)
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1
Q

What is constipation?

A
  • passage of stool infrequently or with difficulty
  • stool frequency of less than 3 per week due to:
    straining, hard stool or incomplete evacuation
2
Q

Epidemiology of constipation?

A
  • adults: 10%
  • elderly: 20-30%:
    22% in elderly living in community
    50% in hospice
    63% in hospitalized elderly
  • women more than men
3
Q

Etiologies of constipation?

A
  • most common: lifestyle
  • inadequate fiber in diet: fiber promotes normal transit time, frequent stools, and lower use of laxatives
  • inadequate hydration
  • inactivity
4
Q

Meds that cause constipation?

A
  • opiates***/narcotics
  • antidepressants
  • CCBs
  • antipsych
  • antiparkinsonian agents
  • anticholinergics
  • Ca, Fe supplements
  • antispasmodics
  • antacids (Ca and Al)
5
Q

Structural abnormalities that may cause constipation?

A
  • carcinoma
  • ischemia
  • volvulus
  • megacolon
  • anorectal disorders: prolapse, rectocele, pelvic floor dysfxn (nerve disorder, delivery)
6
Q

Metabolic causes of constipation?

A
  • hypokalemia
  • hypomagnesemia
  • hypothyroidism**
  • hyperparathyroidism
  • porphyria: genetic hemoglobin disorder
  • addison’s disease (going to have diarrhea most likely)
  • hypercalcemia
7
Q

Neurologic causes of constipation?

A
  • parkinson’s
  • MS
  • autonomic neuropathy
  • Hirschprung disease
  • chagas disease (protozoan, spread by kissing bugs)
  • spinal cord lesions
  • Cerebrovascular disease
8
Q

Systemic causes of constipation?

A
  • amyloidosis
  • scleroderma
  • polymyositis
  • pregnancy
9
Q

Surgical causes of constipation?

A
  • abdominal
  • pelvic
  • colonic
  • anorectal
10
Q

Psych causes of constipation?

A
  • depression (always ask about bowel changes)

- eating disorders

11
Q

Exam of pt with constipation? Who should be further evaluated and tx?

A
  • full hx
  • full physical exam: DRE: stool for occult blood
  • in pts less than 50 with no alarm sxs: may start empiric tx
  • further tx should be performed on pts with any of following:
    over 50
    severe constipation
    signs of organic disorder
    hematochezia
    wt loss
    positive FOBT
12
Q

Eval of constipation?

A
  • KUB, barium enema or colonoscopy (best bet)
  • blood tests:
    glucose
    CBC: anemia -detect colorectal neoplasm
    thyroid
    Ca2+
    Mg+
    Phosphorous
13
Q

When is a colonic transit study done?

A
  • to observe transit time in pts with refractory constipation not responding to conservative measures
14
Q

Most impt form of management in constipation?

A
  • PREVENTION!!!!
  • pt education:
    1. exercise: key stimulus to colon peristalsis and defectation, encourage and enable pt to be mobile or be in upright position
    2. fluid intake: constipated stools are low in water content
    3. fiber intake: acute constipation low on fiber diet, dont give in chronic constipation- just makes it harder, responds poorly
15
Q

Tx of constipation?

A

stool softeners (surfactants):

  • colace (docusate sodium)
  • docustae calcium

laxatives:

  • bulk laxatives: psyllium, methylcellulose, fibercon (polycarbophil), benefiber (wheat dextran)
  • osmotics**: lactulose, sorbitol, polyethylene glycol, Mg citrate, Mg sulfate (caution in renal impairment)

Stimulant laxatives: bisacody, senna
-bowel becomes dependent on stimulants, don’t use chronically

opioid receptor antagonist: methylnaltrexone: approved for palliative care pts, pts on chronic opiod tx, doesn’t effect central analgesia

digital disimpaction: refer,!! You or the pt shouldn’t be doing this!

16
Q

What is diarrhea?

A
  • increase in daily stool wt above 200-300 g/24 hrs
  • clinically: increase in stool liquidity and/or frequency
  • in developed countries:
    normal stool wt of an adult human is less than 200 g/d
  • stool water accounts for 60-85% of wt
  • normal bowel frequency ranges from 3x a week to 3x a day
  • greater than 3x a day is considered abnormal
17
Q

Osmotic diarrhea PP?

A
  • non-absorbable substance draws out excess water into intestines and increases stool wt and volume
18
Q

Secretory diarrhea PP?

A
  • mucosal secretion of fluid and electrolytes secondary to bacterial enterotoxins, neoplasms, or exotoxins
19
Q

Motility diarrhea PP?

A
  • food isn’t mixed properly, digestion is impaired and motility is increased, secondary to resection of small intestine, surgical bypass of an area of intestine or diabetic neuropathy
20
Q

Diff b/t acute, persistent and chronic diarrhea?

A
  • acute: less than or equal to 14 days
  • persistent: more than 14 days in duration
  • chronic: AGA suggests that chronic diarrhea should be defined as decrease in fecal consistency lasting 30 days or more
21
Q

Acute and chronic diarrhea clinical manifestations?

A
  • acute is usually due to infections with viruses and bacteria and are self limited:
    fever, cramping pain, if severe, can get dehydrated** esp in kids or elderly
  • chronic usually secondary to IBS or IBD, or malabsorption syndromes
22
Q

Causes of acute infectious diarrhea?

A
  • viral:
    norovirus, rotavirus, adenovirus, astrovirus
  • bacterial:
    salmonella, campylobacter (GBS), shigella, enterotoxigenic E coli, C diff
  • protozoa: (use wet mount):
    cryptosporidium: most common parastic cause of acute food borne diarrheain US, giardia, cylcospora, entamoeba
23
Q

Causes of noninfectious acute diarrhea?

A
  • drugs
  • food allergies
  • disease states such as thyrotoxicosis and carcinoid syndrome
24
Q

Indications for dx eval of acute diarrhea?

A
  • profuse watery diarrhea with signs of hypovolemia
  • passage of many small volume stools containing blood and mucus
  • bloody diarrhea
  • temp at or greater than 101.3 (38.5 C)
  • passage of 6 or more unformed stools per 24 hours or a duration of illness of more than 48 hrs
  • severe abdominal pain
  • hospitalized pts or recent use of abx
  • diarrhea in elderly (older than 70) or immunocompromised
  • systemic illness with diarrhea, esp in pregnant women (listeriosis should be suspected)
25
Q

Etiologies of chronic diarrhea?

A
  • meds: SSRIs, ARBs, PPIs
  • osmotic: increased osmotic gap - laxative abuse
  • secretory
  • inflammatory: crohns, UC
  • malabsorptive: steatorrhea
  • motility disorders: exercise or stress induced
  • chronic infections
26
Q

Clues that cause of chronic diarrhea is osmotic? Meds?

A
  • stool vol decreases with fasting, increased stool osmotic gap
  • meds: antacids, lactulose, sorbitol
  • disaccharidase deficiency: lactose intolerance
  • facticious diarrhea: Mg (antacids, laxative)
27
Q

Clues that cause of chronic diarrhea is secretory? Causes?

A
  • clues: large vol - over 1 L/day, little change with fasting, normal stool osmotic gap
  • hormonally mediated: carcinoid, medullary carcinoma of thyroid (calcitonin), zollinger-ellison syndrome (gastrin)
  • factitious diarrhea: laxative abuse
  • villous adenoma: secretes K+ rich fluid
  • bile salt malabsorption: ileal resection, crohn ileitis, postcholecystectomy
  • meds
28
Q

Clues of inflammatory causes of diarrhea? Causes?

A
  • clues: fever, hematochezia, abdominal pain
  • IBD: UC or crohns
  • malignancy: lymphoma, adenocarcinoma (w/ obstruction and pseudodiarrhea)
  • radiation enteritis
29
Q

Clues of malasbsorption cause of diarrhea? Causes?

A
  • wt loss, abnorm lab values, fecal fat greater than 10 g/24 hrs
  • small bowel mucosal disorders: celiac sprue, tropical sprue, whipple disease, eosinophilic gastroenteritis, small bowel resection, crowns
  • lymphatic obstruction: lymphoma, carcinonid, infectious (TB, MAI), kaposi sarcoma, sarcoidosis, retroperitoneal fibrosis
  • pancreatic disease: chronic pancreatitis, pancreatic carcinoma
  • bacterial overgrowth: motility disorders - diabetes, vagotomy, scleroderma, fistulas, small intestinal diverticula
30
Q

Motility disorders - that cause chronic diarrhea? Clues?

A
  • clues: systemic disease or prior abdominal surgery
  • postsurgical: vagotomy, partial gastrectomy, blind loop with bacterial overgrowth
  • systemic disorders: scleroderma, DM, hyperthyroidism
  • IBS
31
Q

Chronic infections - can cause chronic diarrhea?

A
  • AIDs related, CMV, HIV
  • bacterial: C diff, mycobacterium avium complex
  • protozoal: Giardia, entamoeba histolytica, microsporida, cryptosporidium
32
Q

Workup of diarrhea? fecal analysis?

A
  • hx: travel, longevity of sxs, family hx, food intake and relationship to onset
  • fecal analysis:
    fecal leukocytes
    fecal occult blood
    fecal fats
    enteric pathogen cultures
    C diff toxin
    ova and parasites
  • other labs: TSH, CBC, CMP with LFTs, ESR, CRP
33
Q

Fecal analysis: fecal leuks finding?

A
  • presence indicated bowel mucosal inflammation, which occurs in invasive bacterial enteritis and UC
34
Q

Fecal occult blood test findings?

A
  • immunochemical tests for fecal blood (FIC or iFOBT) for hemoglobin are more specific than guaiac tests b/c they respond only to human globin and don’t detect upper GI bleeding
  • hemoccult: + result obtained on multiple specimens performed on excessive days
35
Q

Stool for culture and sensitivity - findings?

A
  • enterococcus
  • e-coli
  • clostridium
  • tx with cipro
36
Q

Stool for ova and parasites - findings?

A
  • salmonella
  • shigella
  • giardia
37
Q

C-diff toxin assay findings?

A
  • c-diff multiplies and releases toxin that causes necrosis of colonic epithelium which causes diarrhea
38
Q

Fecal fat findings - etiologies?

A
- quantitative stool fat:
confirms steatorrhea
sprue
crohn's
whipples dz
39
Q

When should an endoscopic exam and bx be done? What other studies are done?

A
  • colonoscopy with mucosal bx to exclude IBD, microscopic colitis, and colonic neoplasia
  • upper endoscopy when small intestine disorder is suspected such as celiac sprue or whipple disease
  • other studies:
    24 hr stool collection (IBS, malabsorption)
    other imaging
40
Q

Tx of diarrhea?

A
  • fluid replacement
  • avoid fatty foods
  • abx therapy: shigelosis, traveler’s diarrhea, pseudomembranous enterocolitis, cholera, parasitic diseases (tx of choice: cipro, or TMP SMX)
  • bismuth subsalicylate (pepto : don’t give to kids)
  • opiate antidiarrheal agents: diphenoxylate (lomotil) and loperamide (immodium): for mid to mod secretory diarrhea
  • cholestyramine (questran): diarrhea caused by ileal bile salt malabsorption