Small Bowel

Question 0

Most common cause of pediatric diarrhea

Answer 0

Rotavirus

Question 1

Types of diarrhea

Answer 1

Infectious, malabsorption, osmotic, increased motility, secretory

Question 2

Ddx of chronic diarrhea

Answer 2

Secretory: carcinoid tumor or VIPoma
Malabsorption/maldigestive/osmotic: bacterial overgrowth, pancreatic insufficiency, mucosal damage, lactose intolerance, celiac dz, laxative abuse, short bowel syndrome
Inflammatory: IBD
Increased motility: IBS

Question 3

When to workup acute diarrhea

Answer 3

Further workup if patient has a high fever, bloody diarrhea, or diarrhea > 4-5 days

Question 4

Watery vs. bloody diarrhea organisms

Answer 4

Watery: Vibrio cholera, ETEC, Giardia, C diff, rotavirus, Cryptosporidium

Bloody: EHEC, Salmonella, Shigella, Campylobacter

Question 5

Campylobacter:

-Hx, Exam, Tx

Answer 5

Hx: most common etiology of bacterial diarrhea; ingestion of contaminated food/water; affects young children and young adults

Exam: Fecal RBCs and WBCs; p/w bloody diarrhea, fever, and no abdominal pain

Tx: erythromycin

Question 6

C diff

-hx, exam, tx

Answer 6

Hx: a/w recent antibiotic use (especially clinda) and recent hospitalization
-be careful about toxic megacolon

Exam: p/w fever, abdominal pain, systemic toxicity; fecal RBCs and WBCs
-causes colitis; dx w/ toxin in stool; sigmoidoscopy shows pseudomembranes

Tx: PO metronidazole or PO vanc; IV metronidazole if pt can’t tolerate PO

Question 7

Entamoeba histolytica

-hx, exam, tx

Answer 7

Hx: 2/2 ingestion of contaminated food or water (Trave)

Exam: severe abdominal pain and fever; fecal RBCs and WBCs; endoscopy shows flask-shaped ulcers”
-mimics IBD if chronic

Tx: steroids can cause fatal perforation. DON’T USE STEROIDS; tx w/ metronidazole

Question 8

E. coli 0157:H7

-Hx, exam, tx

Answer 8

Hx: bloody diarrhea, ingestion of raw meat; lasts 5-10 days

Exam: p/w severe abdominal pain, low-grade fever, vomiting, and bloody diarrhea; fecal RBCs and WBCs
-rule out GI bleed and ischemic colitis; HUR is a potential complication (thrombocytopenia and renal failure)

Tx: avoid antibiotics or antidiarrhea therapy because they increase HUS risk

Question 9

Salmonella

-hx, exam, tx

Answer 9

Hx: 2/2 ingestion of contaminated poultry or eggs

Exam: p/w prodromal HA, fever, myalgia, and abdominal pain

• Fecal WBCs
• sepsis is a concern as 5-10% of pts become bacteremic; sickle cell pts are prone to osteomyelitis

Tx: oral quinolone or TMP-SM if pts are bacteremic or have sickle cell

Question 10

Shigella

-Hx, exam, tx

Answer 10

Hx: very contagious, transmitted fecal-oral

Exam: fecal RBCs and WBCs; bloody diarrhea
-can cause severe dehydration and febrile seizures

Tx: TMP-SMX to prevent spread

Question 11

Intestinal villous atrophy

Answer 11

a/w Celiac disease

Question 12

Dermatitis herpetiformis

Answer 12

a/w celiac dz
grouped, papulovesicular pruritic skin lesions
symmetrically located on extensor surfaces of elbows, knees, buttocks, and posterior scalp

Question 13

Frequent, loose, watery stools which are pale, foul-smelling, bukly
a/w abdominal pain, flatus, bloating, weight loss, nutritional deficiencies, and fatigue

Answer 13

Malabsorptive diarrhea
ddx: mucosal (Celiac, Whipples dz, tropical sprue), bile salt deficiency (bacterial overgrowth), pancreatic insufficiency, or short bowel syndrome

Question 14

Pellagra

Answer 14

Sx: Diarrhea, dementia, dermatitis, death
-high sensitivity to sunlight; ataxia, confusion, insomnia; beefy, red glossitis; dilated cardiomyopathy;

Vitamin B3 (niacin) deficiency 2/2 decreased niacin or tryptophan intake

Question 15

Lactose intolerance:

-pathophysiology, common populations, hx/PE, Dx, Tx

Answer 15

Pathophysiology: lack of lactose; can occur after gastroenteritis transiently; common in Asian, Native Americans, and Africans

Hx/PE: abdominal bloating, flatulence, cramping, watery diarrhea after milk ingestion
Dx: empiric lactose-free diet that improves symptoms
-Hydrogen breath test reveals increased hydrogen after ingestion of lactose

Tx: avoid dairy products

Question 16

Carcinoid syndrome vs. carcinoid tumor

Answer 16

Syndrome: after tumor mets to liver
Tumor: presence of carcinoid tumor

Question 17

What do carcinoid tumors produce?

Answer 17

Serotonin

Question 18

Why are there no sx before carcinoid tumor metastasizes?

Answer 18

Serotonin undergoes first-pass metabolism in the liver

Question 19

Carcinoid syndrome

-sx, dx, tx

Answer 19

Flushing, diarrhea
Abdominal cramps, wheezing, right-sided cardiac valvular lesions

Dx: high urine levels of 5-HIAA; CT and In-111 octreotide scans can localize the tumor

Tx: octreotide and surgical resection

Question 20

Constipation, abdominal distention, mucous stools and abdominal pain that relieved by bowel movements

Answer 20

Irritable bowel syndrome

Question 21

Partial vs complete SBO

Answer 21

Partial: continued passage of flatus
Complete: no passage of flatus or stool

Question 22

Causes of small bowel obstruction

Answer 22

Most common: adhesions, hernias

Neoplasms, intussusception, gallstone ileus, stricture, volvulus

Question 23

Typical symptoms of an SBO

Answer 23

Crampy abdominal pain at 4-5 minute intervals
Vomiting: proximal = early and bilious; distal = late and feculent
Exam: distention
Bowel sounds: high-pitched tinkles and peristaltic rushes

Question 24

Pt w/ hx of carcinoid tumor (resected) who presents with symmetric, dry, b/l hyperpigmented skin lesions, persistent diarrhea, and complaints that she is not herself anymore (irritable, confused, forgetful). Likely diagnosis?

Answer 24

Pellagra 2/2 carcinoid syndrome recurrence
-Carcinoid tumors produce serotonin which is derived from tryptophan. Tryptophan is also the precursor of niacin, so patients with carcinoid tumors may be using all of their tryptophan for serotonin production and not making enough niacin

Question 25

Dx of small bowel obstruction

Answer 25

Abxominal films stepladder pattern of dilated small-bowel loops, air fluid levels, and paucity of gas in the colon

Question 26

Tx of partial and complete SBO

Answer 26

Partial: NPO, NG tube, IVF, correction of electrolyte abnormalities, and Foley to monitor fluid status
-if sx > 3 days, then do ex-lap
Complete: ex-lap

Question 27

Gallstone ileus

Answer 27

SBO where gallstone erodes through intestinal wall into the lumen of the GI tract and lodges in the ileocecal valve

Question 28

Obstruction vs. ileus

Answer 28

Obstruction: physical obstruction in the bowel causing backup
Ileus: loss of peristalsis without structural obstruction

Obstruction has hyperactive bowel sounds while ileus has none

Question 29

X ray differences between ileus and SBO

Answer 29

SBO has air in small bowel, none in colon (distal to the SBO)
Ileus has diffuse air present throughough the GI tract

Question 30

Tx for ileus

Answer 30

NPO, NG suction, TPN, IVF

Question 31

2 most common causes of mesenteric ischemia

Answer 31

Thrombotic occlusion: acute thrombosis in the SMA. primary risk = atherosclerosis
Embolism: from heart; risks = a-fib and stasis from a decreased ejection fraction

Question 32

Intestinal angina

Answer 32

Episodes of pain after eating related to increased blood needs for the gut and inability to get it due to atherosclerosis

Question 33

Pneumatosis intestinalis

Answer 33

Air within the bowel
In neonates = necrotizing enterocolitis
In adults it can mean mesenteric ischemia

Question 34

Tx of acute bowel ischemia

Answer 34

Volume resuscitation and antibiotics
Acute arterial thrombosis/embolus: anticoagulation and laparotomy
Venous thrombosis: anticoagulation
Surgical resection of infarcted bowel