Lower GI

Question 1

Irritable Bowel Syndrome

Answer 1

Question 2

Red Flags

Answer 2

– Unintentional and unexplained weight loss

– Rectal bleeding

– Family history of bowel or ovarian cancer

– Change in bowel habits persisting MORE than 6 weeks in a person > 60

Question 3

Irritable Bowel Syndrome Treatment

Answer 3

• Fiber is ineffective in the treatment of adult IBS
• Lubiprostone (Amitiza) and Linaclotide (Linzess) are effective for constipation-predominant IBS.

– Works by increasing the amount of fluid in intestine, making it easier for stool to pass

• Antispasmodics – Dicyclomine, tincture of belladonna, hyoscyamine
• Antidepressants (Citalopram, Fluoxetine, Paroxetine; tricyclic antidepressants have been studied)

– Low dose: Analgesia, mood, colonic transit slowing

• Antidiarrheal agents – Diphenoxylate, loperamide; no help with pain

Question 4

Celiac Disease Diagnosis

Answer 4

• Several serologic tests are readily available for diagnosis.

– IgA anti-tissue transglutaminase antibody*§ (sensitivity 79%-90%, specificity 98%, most senstive)

If positive confirm with biopsy.

• Test while consuming a diet of gluten-containing foods.
• Gold standard: Endoscopy biopsy of proximal small intestinal mucosa – villous atrophy

Question 5

A 19-year-old patient presents to your office for follow-up. She reports continued intermittent abdominal cramping and bloating, diarrhea, fatigue, and a 4.5-kg weight loss. She initially was diagnosed with irritable bowel syndrome, but you suspect celiac disease. What should be used to establish the diagnosis?

Answer 5

Serologic testing initially, followed by endoscopy if test results are positive

Question 6

Ulcerative Colitis Pathology

Answer 6

– CONFINED TO MUCOSA – Starts in rectum, moves proximally WITHOUT skips

Question 7

What is UC linked to?

Answer 7

Ulcerative Colitis Link With Colon Cancer

• 2.8-15x as likely to develop colon cancer if there is history of moderate or extensive involvement of the colon

• Colonoscopy q 2-5 years

– Initiated 10 years after UC is diagnosed

– Interval based on findings

Crohn’s has similar cancer risk as UC after long-standing disease – similar screening recommendation and controversy

Question 8

Crohn’s Disease Pathology

Answer 8

– FULL WALL THICKNESS

– Any part of GI tract may be affected.

– Terminal ileum most common site

– SKIPS

Question 9

UC versus Crohn’s

Answer 9

Question 10

Treatment for UC

Answer 10

Question 11

Treatment for chronh’s

Answer 11

Question 12

In considering the treatment of a patient with Crohn’s Disease, which of the following statements is true?

A. Budesonide is not effective in inducing remission

B. Azathioprine is effective for maintenance of remission

C. Methotrexate is effective in inducing but not maintaining remission

D. Sulfasalazine and 5-aminosalicylic acid are first line agents in the treatment of severe disease activity

Answer 12

B. Azathioprine is effective for maintenance of remission

Question 13

Summary of Serological tests

Answer 13

Question 14

(Viral) Gastroenteritis

Answer 14

Majority of Gastroenteritis Is Viral

• Rotavirus is the most common cause in children and produces similar incidence rates in both the developed and developing world.
• Norovirus is the leading cause of gastroenteritis among adults in America, causing greater than 90% of outbreaks.

Question 15

Complications of Rotavirus

Answer 15

Complications: Necrotizing enteritis, biliary atresia, intussusception, chronic diarrhea

Question 16

Rotavirus vaccination

Answer 16

• 2 months – First dose minimum 6 weeks, maximum < 15 weeks
• 4 months
• 6 months – Must complete by 8 months

Question 17

A 52-year-old female with hypertension presents with a 2-day history of profuse bloody diarrhea, moderate to sever abdominal cramping, and fever. She has recently returned from a week-long trip to Singapore. Her stool culture is positive for Campylobacter. What is the treatment of choice?

Answer 17

Azithromycin (Zithromax)

Question 18

Bacterial Gastroenteritis in children and adults

Answer 18

Question 19

Campylobacter

Answer 19

• Animal reservoir – Most human cases are contaminated poultry (~50%)

Severe cramps, bloody diarrhea, anorexia, malaise; rarely, Guillain-Barre, reactive arthritis

• Diagnosis: Culture
• Treatment

– Spontaneous clearing without antibiotics or

– Azithromycin, Erythromycin if culture proven

Question 20

Shigella treatment

Answer 20

• Bloody diarrhea • Fecal oral spread – Highly contagious • Principal effect on colon mucosa – Low-volume diarrhea – Blood – Mucus – Fever – Tenesmus • Diagnosis – Culture

– TMP-SMX (children)

– Quinolone adults

Question 21

Salmonellosis

Answer 21

• Sources – Eggs and poultry – Pet reptiles

– Self-limited

• Typhoid via fecal-oral contamination, rare in US – Constipation and rash early, then diarrhea and pain – Diagnosis • Culture from blood or stool

– Treat • Fluoroquinolone • Vaccine available

Question 22

E. coli 0157:H7 (EHEC)

Answer 22

• Complication – Hemolytic uremic syndrome
• Source – Contaminated meat
• Treatment – Supportive – Antibiotic NOT indicated

Question 23

Amebiasis

Answer 23

• E. histolytica mostly – Fecal-oral spread – Abdominal cramps – Chills, fever – Liquid BMs with bloody mucus
• Diagnosis – Sigmoidoscopy – O&P – Stool/serum antigen – Serology
• Treatment – Metronidazole etc.

Question 24

Giardiasis

Answer 24

• Common – Mostly from contaminated water
• Symptoms – Abdominal cramps – Malabsorption – Nausea and vomiting – Watery diarrhea
• Diagnosis – O&P – Giardia antigen assay
• Treatment – Metronidazole

Question 25

Pseudomembranous Enterocolitis

Answer 25

* Common in “post-antibiotic” setting * **Etiology** – Toxin from Clostridium difficile * **Diagnosis** – Cytotoxin assays – Immunoassays to toxin **• Treatment** – Stop antibiotic – use metronidazole or vancomycin • No reported resistance – Fluids

Question 26

Traveler's Diarrhea Prophylaxis

Answer 26

• Prophylaxis – NOT recommended by CDC – Routine prophylaxis increases the traveler’s risk for adverse reactions and for infections with resistant organisms.

Question 27

Traveler’s Diarrhea (TD) If Treatment Is Needed …

Answer 27

* Travelers who develop **\> 3 loose stools in an 8-hour period** – especially if associated with nausea, vomiting, abdominal cramps, fever, or blood in stools * Antibiotics\* – **Fluoroquinolones** (cipro) are drugs of choice when needed single dose or 1 day (increasing resistance) – Alternative: Azithromycin (500 mg q day for 1-3 days) * **Bismuth subsalicylate** may also be used for treatment. – One fluid oz or two 262 mg tablets q 30 minutes for up to eight doses in a 24-hour period

Question 28

Vibrio Cholerae

Answer 28

* In US, generally associated with travel • Asia • China • South/Central America – OR consumption of contaminated seafood – OR recent consumption of contaminated imported foods * Treatment – Vigorous rehydration – **Doxycycline**

Question 29

Key Learning Points: Diarrhea

Answer 29

* **Rotavirus** is the leading cause of infectious diarrhea in children in the US. * **Norovirus** is the leading cause of foodborne disease in US and the leading cause of gastroenteritis in US adults. * **Salmonalla** is the most common cause of bacterial diarrhea in adults in the US. * Antibiotics are not indicated for treatment of E. coli 0157:H7. * Amoxicillin is most common offending antibiotic for pseudomembranous enterocolitis. * Prophylaxis for traveler’s diarrhea is NOT recommended.

Question 30

Diverticulosis

Answer 30

Question 31

Diverticulitis Clinical presentation & physical findings

Answer 31

• Clinical presentation – Acute lower abdominal pain – Fever (usually below 102º F) – Tachycardia – Physical findings • Tender lower abdomen, possibly with rebound – Tenderness only in the LLQ significantly increases the likelihood of diagnosis ([+] LR = 10.4). • Acute abdomen is possible

Question 32

Diverticulitis Diagnostic Studies

Answer 32

Question 33

Diverticulitis Treatment

Answer 33

• General – Depends on severity – May require only clear liquids and oral antibiotics * Can be done outpatient with follow-up in 2-3 days * Ciprofloxacin and/or metronidazole – OR MAY NEED (hospitalization) • NPO • NG suction • IV fluids • IV antibiotics – Ampicillin + aminoglycoside + metronidazole OR – Imipenem/cilastatin OR – Piperacillin/tazobactam

Question 34

Second most frequent cause of cancer death AFTER lung cancer

Answer 34

Cancer of Large Intestine

Question 35

Recommendation of the USPSTF on Screening for CRC

Answer 35

The FIT is preferred over the gFOBT because it is better at detecting cancer and it doesn't require dietary restrictions before testing, according to the U.S. Multi-Society Task Force (MSTF) on Colorectal Cancer. A colonoscopy examines the entire colon, while a sigmoidoscopy covers only the lower part of the colon, also known as the rectum and sigmoid colon

Question 36

Guidelines for Follow-up Surveillance Colonoscopy

Answer 36

Question 37

Types of Polyps

Answer 37

Question 38

One week after a complete and adequate baseline screening colonoscopy, a 51-year-old female with no history of previous health problems visits you to review the pathology report on the biopsy specimen obtained from the solitary 8-mm polyp discovered in her sigmoid colon. The report confirms that this was a hyperplastic polyp. Her family history is negative for colon cancer. Which one of the following is the most appropriate interval for follow-up colonoscopy in this patient?

Answer 38

10 years