GATEOENTEROLOGY 1.2 (AB) Flashcards
What is the gold standard diagnostic test for Hirschsprung Disease (Congenital Aganglionic Megacolon)?
Rectal suction biopsy
What developmental disorder is characterized by absence of ganglion cells in the submucosal and myenteric plexus?
Hirschsprung Disease (Congenital Aganglionic Megacolon)
What is the most common cause of lower intestinal obstruction in neonates?
Hirschsprung Disease
What is the incidence of Hirschsprung Disease?
1 in 5,000 live births
What is the male-to-female ratio in short-segment Hirschsprung Disease?
0.16736111111111107
What is the male-to-female ratio in total colonic aganglionosis?
~2:1
What is the pathophysiology of Hirschsprung Disease?
Arrested migration of neuroblasts causing absence of myenteric and submucosal plexus, leading to inadequate bowel relaxation and obstruction
What are the classic neonatal clinical manifestations of Hirschsprung Disease?
Distended abdomen, failure to pass meconium, bilious emesis, feeding intolerance
What neonatal conditions should Hirschsprung Disease be differentiated from?
Meconium plug syndrome, meconium ileus, intestinal atresia
What is the Currarino triad associated with older patients with Hirschsprung Disease?
Anorectal malformations, sacral bone anomalies, presacral anomaly
What are examples of anorectal malformations in Currarino triad?
Ectopic anus, anal stenosis, imperforate anus
What are examples of sacral bone anomalies in Currarino triad?
Hypoplasia, poor segmentation
What are examples of presacral anomalies in Currarino triad?
Anterior meningoceles, teratoma, cyst
What is intussusception?
Telescoping of one part of the intestine into an adjacent segment
What is the segment that invaginates called in intussusception?
Intussusceptum
What is the receiving segment called in intussusception?
Intussuscipiens
What is the most common cause of intestinal obstruction between 5 months and 3 years?
Intussusception
What is the most common abdominal emergency in children younger than 2 years?
Intussusception
What stool characteristic is pathognomonic for intussusception?
Currant jelly stool
What physical exam finding is characteristic of intussusception?
Sausage-like mass
What ultrasound finding is characteristic of intussusception?
Target sign
What is the treatment for intussusception?
Surgery
What is peptic ulcer disease (PUD)?
Inflammatory condition caused by imbalance between cytoprotective and cytotoxic factors in stomach and duodenum
What are the key factors in peptic ulcer disease pathogenesis?
Acid and pepsin (damage), mucosal defense failure
What are the two types of peptic ulcers?
Primary (chronic, duodenal), Secondary (acute, stress-related)
Where are gastric ulcers usually located?
Lesser curvature of the stomach
Where do 90% of duodenal ulcers occur?
Duodenal bulb
What is the main causative factor for mucosal injury in PUD?
Acid-pepsin activity
What are examples of mucosal defense defects in PUD?
Impaired mucus-bicarbonate barrier, reduced prostaglandin synthesis, decreased mucosal blood flow
What bacterial infection is a contributing factor for peptic ulcer disease?
Helicobacter pylori infection
What medication class contributes to peptic ulcer disease by inhibiting prostaglandin synthesis?
NSAIDs
What symptoms are associated with peptic ulcer disease?
Epigastric pain, nausea, vomiting, hematemesis, melena
What are severe complications of peptic ulcer disease?
Perforation, obstruction
What is the causative agent of Helicobacter pylori gastritis?
Helicobacter pylori (Gram-negative, S-shaped rod)
How is Helicobacter pylori transmitted?
Fecal-oral or oral-oral (e.g., kissing)
What are key enzymes produced by Helicobacter pylori?
Urease, catalase, oxidase
What gastric condition is commonly associated with H. pylori but often asymptomatic?
Chronic active gastritis
What extragastric conditions can H. pylori infection cause?
Iron deficiency anemia, idiopathic thrombocytopenic purpura (ITP), short stature
What malignancies are linked to H. pylori infection?
Gastric adenocarcinoma, MALT lymphoma
What is the gold standard diagnostic method for H. pylori?
Endoscopy with biopsy
What non-invasive test for H. pylori detects urease activity?
13C-Urea breath test
What stool-based test is highly sensitive and specific for H. pylori, especially in children?
Stool antigen test
What is the first-line eradication therapy for H. pylori?
Triple therapy: PPI + Amoxicillin + Clarithromycin for 14 days
What is the recommended treatment for resistant H. pylori infection?
Quadruple therapy: PPI + Bismuth + Metronidazole + Tetracycline
What medication should be discontinued 2 weeks before H. pylori testing to avoid false negatives?
PPI
What classification does WHO assign to Helicobacter pylori?
Group I carcinogen
What is the relative risk increase for gastric cancer in H. pylori-infected adults?
2.3 to 8.7 times higher
How does urease contribute to H. pylori pathogenesis?
Converts urea to ammonia, neutralizing acid but damaging mucosa
What are the invasive methods to diagnose H. pylori?
Endoscopy with biopsy, histologic exam with Giemsa stain
What are the non-invasive methods to diagnose H. pylori?
13C-Urea breath test, stool antigen test
