GI Disorders

Question 1

2-5 yo patient, with early morning onset of vomiting attacks >4x in an hour for several hours, preceded by nausea, pallor, noise and light hypersensitivity, lethargy and headache. Attacks have occured more than 5 times in the past 6 mos, precipitated by infection, psychological or physical stress. Careful investigation in the past months ruled out any other cause of vomiting. Px appears well and asymptomatic in between attacks.

What is the probable diagnosis? What is the treatment for this condition?

Answer 1

cyclic vomiting

• Rome III criteria for fcnl GI disorders (FGID) (both must be present)
  1. 2 or more periods of intense nausea and unremitting vomiting or retching lasting hours to days
  2. return to usual state of health lasting weeks to months

Consensus definition:
• At least 5 attacks in any interval, or a minimum of 3 attacks during a 6-month period
• Episodic attacks of intense nausea and vomiting lasting 1hr to 10 days and occurring at least 1wk apart
• Stereotypical pattern and symptoms in the individual patient
• Vomiting during attacks occurs ≥4 times/hr for ≥1hr
• Return to baseline health between episodes
• Not attributed to another disorder

• tx: hydration and antiemetics, address complications of vomiting

Question 2

What is the definition of acute and chronic diarrhea?

Answer 2

Acute: sudden onset of excessively loose stools of >10 ml/kg/day in infants or >200 g/day in older children, which lasts < 14 days
Chronic: >14 days

• Disorders that interfere with absorption in the small bowel tend to produce voluminous diarrhea, whereas disorders compromising colonic absorption produce lower-volume diarrhea

Question 3

What are the more probable causes of true constipation in infancy?

Answer 3

Hirschsprung disease
intestinal pseudo-obstruction
hypothyroidism

Question 4

Two types of nerve fibers transmit painful stimuli in the abdomen. Which pain fibers mediate the following:

1. sharp, localized pain
2. poorly localized, dull pain

Answer 4

1. in skin and muscle - A fibers

2. from viscera, peritoneum, and muscle - C fibers

Question 5

Acute epigastric and left upper quadrant pain radiating to the back, characterized as constant, sharp, and boring, accompanied by nausea, emesis, tenderness

probable diagnosis?

Answer 5

acute pancreatitis

Question 6

Acute or gradual periumbilical to lower abdominal pain referred to the back, colicky in character (alternating cramping and painless periods), associated with distention, obstipation, emesis, and increased bowel sounds.

Probable diagnosis?

Answer 6

intestinal obstruction

Question 7

Acute, sharp and steady periumbilical abdominal pain which localizes to lower right quadrant with generalized peritonitis, which may radiate to back or pelvis, accompanied by anorexia, nausea, emesis, local tenderness, and fever if with peritonitis.

probable diagnosis?

Answer 7

acute appendicitis

Question 8

Acute periumbilical to lower abdominal pain, characterized as cramping with painless periods, associated with hematochezia, knees usually in pulled-up position

Answer 8

intussusception

Question 9

Acute and sudden unilateral back pain with referral to the groin, characterized as sharp, intermittent and cramping, associated with hematuria

Probable diagnosis?

Answer 9

urolithiasis

Question 10

Acute dull to sharp back pain with referral to the bladder associated with fever, CVA tenderness, dysuria and urinary frequency

probable diagnosis?

Answer 10

urinary tract infection

Question 11

Red or maroon blood in stools, signifies either a distal bleeding site or massive hemorrhage above the distal ileum

a. hematemesis
b. hematochezia
c. melena

Answer 11

b. hematochezia

Question 12

Moderate to mild bleeding from sites above the distal ileum or major hemorrhages in the duodenum and above tend to cause blackened stools of tarry consistency

a. hematemesis
b. hematochezia
c. melena

Answer 12

c. melena

Question 13

What is the most common cause of bleeding in the GI tract?

Answer 13

Erosive damage to the mucosa

• variceal bleeding secondary to portal hypertension occurs often enough to require consideration

Question 14

What are the specific diagnostic modalities utilized in the following cases:

a. UGIB
b. LGIB
c. small intestines
d. occult blood in stool
e. brisk intestinal bleeding of unknown location

Answer 14

a. UGIB - esophagogastroduodenoscooy (EGD)
b. LGIB - colonoscopy
c. small intestines - capsule endoscopy
d. occult blood in stool - guaiac test
e. unknown location of bleed - RBC scan

Question 15

Prolonged elevation of the serum levels of conjugated bilirubin beyond the 1st 14 days of life

Answer 15

neonatal cholestasis

• Jaundice that appears after 2wk of age, progresses after this time, or does not resolve at this time should be evaluated and a conjugated bilirubin level determined
• mechanical obstruction of bile flow or functional impairment of hepatic excretory function and bile secretion

Question 16

Idiopathic familial intrahepatic cholestasis associated with lymphedema of the lower extremities

Answer 16

Aagenaes syndrome

• relationship between liver disease and lymphedema is not understood
• Affected patients usually present with episodic cholestasis

Question 17

Rare autosomal recessive genetic disorder marked by progressive degeneration of the liver and kidneys

Answer 17

Zellweger (cerebrohepatorenal) syndrome

• Affected infants have severe, generalized hypotonia and markedly impaired neurologic function with psychomotor retardation.
• fatal in 6-12 mos

Question 18

the most common syndrome with intrahepatic bile duct paucity, marked reduction in the number of interlobular bile ducts in the portal triads, with normal-sized branches of portal vein and hepatic arteriole

Answer 18

Alagille syndrome (arteriohepatic dysplasia)

Question 19

The most common form of biliary atresia, accounting for ∼85% of the cases

Answer 19

obliteration of the entire extrahepatic biliary tree at or above the porta hepatis

Question 20

Ultrasonographic triangular cord (TC) sign, which represents a cone-shaped fibrotic mass cranial to the bifurcation of the portal vein, may be seen in patients with this condition

Answer 20

biliary atresia

Question 21

The most valuable procedure in the evaluation of neonatal hepatobiliary diseases and provides the most reliable discriminatory evidence

Answer 21

Percutaneous liver biopsy

• Biliary atresia is characterized by bile ductular proliferation, the presence of bile plugs, and portal or perilobular edema and fibrosis, with the basic hepatic lobular architecture intact.
• In neonatal hepatitis, there is severe, diffuse hepatocellular disease, with distortion of lobular architecture, marked infiltration with inflammatory cells, and focal hepatocellular necrosis; the bile ductules show little alteration

Question 22

A highly coordinated reflex process that may be preceded by increased salivation and begins with involuntary retching.

Answer 22

vomiting

• process is coordinated in the medullary vomiting center

Question 44

What is the underlying mechanism in diarrhea caused by the ff agents: cholera toxin, ETEC, carcinoid, C. difficile

a. mucosal invasion
b. decreased surface area
c. decreased motility
d. increased motility
e. osmotic
f. secretory

Answer 44

f. secretory

• increased secretion, decreased absorption
• watery and large volume
• PERSISTS with fasting

Question 45

What is the underlying mechanism in diarrhea caused by the ff agents: Salmonella, Shigella, amebiasis, Yersinia

a. mucosal invasion
b. decreased surface area
c. decreased motility
d. increased motility
e. osmotic
f. secretory

Answer 45

a. mucosal invasion

- organisms cause inflammation, decreases colonic reabsorption, increases motility

Question 46

What is the underlying mechanism in diarrhea caused by the ff agents: lactase deficiency, lactulose, laxative overdose

a. mucosal invasion
b. decreased surface area
c. decreased motility
d. increased motility
e. osmotic
f. secretory

Answer 46

e. osmotic

• due to maldigestion, usually low in volume
• STOPS with fasting

Question 47

What is the underlying mechanism in diarrhea caused by the ff agents: short bowel, celiac disease, rotavirus

a. mucosal invasion
b. decreased surface area
c. decreased motility
d. increased motility
e. osmotic
f. secretory

Answer 47

b.decreased surface area

• decreased functional capacity
• watery

Question 48

What is the underlying mechanism in diarrhea caused by the ff agents: irritable bowel syndrome, thyrotoxicosis

a. mucosal invasion
b. decreased surface area
c. decreased motility
d. increased motility
e. osmotic
f. secretory

Answer 48

d. increased motility

• decreased transit time
• loose to normal stools

Question 49

Among disk button batteries, coins, or small plastic toys, which should be removed expediently because they can induce mucosal injury in as little as 1hr of contact time and involve all esophageal layers within 4hr?

Answer 49

disk button batteries

• Asymptomatic blunt objects and coins lodged in the esophagus can be observed for up to 24hr in anticipation of passage into the stomach

Question 50

Between acidic and alkali caustic ingestions, which is ingested in greater volume because it is tasteless and not bitter?

Answer 50

liquid alkali substances produce severe, deep liquefaction necrosis; drain decloggers are most common, and because they are tasteless, more is ingested

alkali - liquefaction necrosis
acid - coagulation necrosis

Question 51

What is the recommended acute treatment for caustic ingestion?

a. dilution by milk or water
b. neutralization
c. induced emesis
d. gastric lavage

Answer 51

a. dilution with milk or water

- all other choices are contraindicated

Question 52

What is the most common type of esophageal atresia?

Answer 52

type A: the upper esophagus ends in a blind pouch and the TEF is connected to the distal esophagus

• Esophageal atresia (EA) is the most common congenital anomaly of the esophagus; of these, >90% have an associated tracheoesophageal fistula (TEF).

Question 53

Newborn was noted to be frothing and bubbling at the mouth and nose after birth as well as episodes of coughing, cyanosis, and respiratory distress. Feeding exacerbates these symptoms, causes regurgitation, and can precipitate aspiration. At the NICU,there was an inability to pass a nasogastric or orogastric tube.

What is your probable diagnosis?

Answer 53

EA with TEF
(esophageal atresia with tracheoesophageal fistula)

• H type fistula (TEF without EA) is usually later in life with chronic respiratory problems, including refractory bronchospasm and recurrent pneumonias

Question 54

What is the underlying mechanism in diarrhea caused by the ff agents: pseudoobstruction, blind loop

a. mucosal invasion
b. decreased surface area
c. decreased motility
d. increased motility
e. osmotic
f. secretory

Answer 54

c. decreased motility

• defect in neuromuscular unit
• bacterial overgrowth

Question 55

What is the management of patients with suspected biliary atresia?

Answer 55

All patients with suspected biliary atresia should undergo exploratory laparotomy and direct cholangiography to determine the presence and site of obstruction

For patients in whom no correctable lesion is found, the hepatoportoenterostomy (Kasai) procedure should be performed

• *transection of the porta hepatis with anastomosis of bowel to the proximal surface of the transection might allow bile drainage
• *success rate of Kasai is greater (90%) if performed before 8wks of life
• *short-term benefit - decompression and drainage sufficient to forestall onset of cirrhosis, until liver transplant can be done

Question 56

To prevent malnutrition, patients with persistent cholestasis may benefit from replacement of dietary formula and supplements containing

a. long chain triglycerides
b. medium chain triglycerides

Answer 56

b. medium chain triglycerides

• Decreased delivery of bile acids to the proximal intestine leads to inadequate digestion and absorption of dietary long-chain triglycerides and fat-soluble vitamins.
• Malnutrition may result from malabsorption of dietary long-chain triglycerides. Replace with dietary formula or supplements containing medium-chain triglycerides

Question 57

What are the concomitant clinical impairments to be expected in a patient with persistent cholestasis?

Answer 57

fat soluble vitamin malabsorption (vit A,D,E,K)
micronutrient deficiency (Ca, phosphate, Zn)
deficiency of water soluble vitamins
Retention of biliary constituents such as cholesterol (itch or xanthomas)
Progressive liver disease; portal hypertension (variceal bleeding, ascites, hypersplenism)
End stage liver disease

Question 58

What is the most common cause of cholestasis with onset after the neonatal period?

Answer 58

acute viral hepatitis or exposure to hepatotoxic drugs

Question 59

Identify which serologic marker for HBV infection is being described:

the first serologic marker of infection to appear and is found in almost all infected persons; its rise closely coincides with the onset of symptoms

Answer 59

HBsAg

Question 60

Identify which serologic marker for HBV infection is being described:
During recovery from acute infection, because HBsAg levels fall before symptoms wane, this might be the only marker of acute infection; rises early after the infection and remains positive for many months, a valuable serologic marker of acute HBV infection

Answer 60

anti-HBc IgM

• remains positive for many months before being replaced by anti-HBc IgG, which then persists for years

Question 61

Identify which serologic marker for HBV infection is being described:
marks serologic recovery and protection

Answer 61

anti-HBs

Question 62

Identify which serologic marker for HBV infection is being described:
the only marker present in persons immunized with hepatitis B vaccine

Answer 62

anti-HBs

Question 63

Identify which serologic marker for HBV infection is being described:
detected in persons with resolved infection (2)

Answer 63

anti-HBs and anti-HBc

Question 64

Identify which serologic marker for HBV infection is being described:
present in active acute or chronic infection and is a marker of infectivity

Answer 64

HBeAg

Question 65

Identify which serologic marker for HBV infection is being described:
marks improvement and is a goal of therapy in chronically infected patients

Answer 65

anti-HBe

Question 66

If treatment for HBV infection is largely supportive, what would be the goals of treatment?

Answer 66

goal of treatment is to reduce viral replication as defined by

1. undetectable HBV DNA in the serum
2. development of anti-HBe

Question 67

The most likely hepatotropic virus to cause chronic infection

Answer 67

Hepatitis C virus (C=chronic)

Question 68

What is the initial symptom of pyloric stenosis?

Answer 68

nonbilious vomiting

• vomiting may or may not be projectile initially but is usually progressive, occurring immediately after a feeding
• starts after 3wk of age
• As vomiting continues, a progressive loss of fluid, hydrogen ion, and chloride leads to hypochloremic metabolic alkalosis

Question 69

What is the most common clinical association of pyloric stenosis?

Answer 69

Hyperbilirubinemia

• also known as icteropyloric syndrome
• Unconjugated hyperbilirubinemia is more common
• usually resolves with surgical correction

Question 70

Patient presents with nonbilious vomiting, usually postprandial, nonprojectile, but progressive. Vomiting started at 3 wks of age. Parents noted an abdominal mass which, upon palpation by the pediatrician, was firm, movable, ∼2cm in length, olive shaped, hard, best palpated from the left side, and located above and to the right of the umbilicus in the mid-epigastrium beneath the liver’s edge.

What will you recommend as ancillary procedure to confirm the diagnosis?

Answer 70

1. This is a classic description of hypertrophic pyloric stenosis.
2. Ultrasound examination confirms the diagnosis in the majority of cases. Criteria for diagnosis include pyloric thickness 3-4mm, an overall pyloric length 15-19mm, and pyloric diameter of 10-14mm

Question 71

On barium contrast studies, what are the classic signs noted in pyloric stenosis?

Answer 71

• elongated pyloric channel (string sign)
• bulge of the pyloric muscle into the antrum (shoulder sign)
• parallel streaks of barium seen in the narrowed channel (“double tract sign”)

Question 72

What metabolic disturbance is expected in children with pyloric stenosis?

Answer 72

hypochloremic metabolic alkalosis

-chronic vomiting will induce loss of fluid, H+, and chloride

Question 73

What is the surgical procedure of choice in correcting pyloric stenosis?

Answer 73

surgical procedure of choice is pyloromyotomy

Question 74

What should be first suspected in an infant or child presents with painless rectal bleeding?

Answer 74

Meckel diverticulum

• because Meckel dicerticulum accounts for 50% of all lower GI bleeds in children <2 y/o

Question 75

What is the most sensitive diagnostic procedure that could confirm a diagnosis of Meckel diverticulum?

Answer 75

Meckel radionuclide scan, which is performed after intravenous infusion of technetium-99m pertechnetate

• treatment is surgical excision

Question 76

Deep mucosal lesions that disrupt the muscularis mucosa of the gastric or duodenal wall are called

Answer 76

peptic ulcers

Question 77

Where is the most common location of gastric ulcers and duodenal ulcers?

Answer 77

Gastric ulcers are generally located on the lesser curvature of the stomach, and 90% of duodenal ulcers are found in the duodenal bulb

primary peptic ulcers - chronic, duodenal. (p-d imagine an inverted p in d of ‘duodenal’), associated with H. pylori
secondary peptic ulcers - acute, often gastric (S-gaStric)

Question 78

What are the secretagogues that promote gastric acid production?

Answer 78

acetylcholine, histamine and gastrin

Ach - vagus nerve
histamine - enterochromaffin cells
gastrin - G cells of the antrum

prostaglandins - enhance protective mucin production, decrease gastric acid secretion

Question 79

The classic symptom of peptic ulceration, epigastric pain alleviated by the ingestion of food, is present only in a minority of children. What are the common symptoms in the ff age groups?

1. newborn
2. infants and younger children
3. older children
4. school-aged children and adolescents

Answer 79

1. newborn - gastric perforation
2. infants and younger children - feeding difficulty, vomiting, crying episodes, hematemesis, or melena
3. older children - Dyspepsia, epigastric abdominal pain or fullness
4. school aged children and adolescents - epigastric pain and nausea

• Hematemesis or melena is reported in up to half of the patients with peptic ulcer disease.

Question 80

What is the recommended regimen for H. pylori eradication?

Answer 80

amoxicillin 14d + clarithromycin 14d + PPI 1 mo
amoxicillin + metronidazole + PPI
clarithromycin + metronidazole + PPI

• The first-line drugs for the treatment of gastritis and peptic ulcer disease in children are H2 receptor antagonists and PPIs
• Antibiotics + PPI must be used for the treatment of H. pylori-associated ulcers
• Triple therapy yields a higher cure rate than dual therapy

Question 81

A rare syndrome characterized by refractory, severe peptic ulcer disease caused by gastric hypersecretion due to the autonomous secretion of gastrin by a neuroendocrine tumor, a gastrinoma

Answer 81

Zollinger-Ellison Syndrome

• common in patients with multiple endocrine neoplasia (MEN1) and rare with neurofibromatosis and tuberous sclerosis
• diagnosis is suspected by the presence of recurrent, multiple, or atypically located ulcers