Definition
• Damage to mucosal lining of upper GI tract 2/2 imbalance btw protective fxn of mucus and bicarb secretion and damage from gastric acid and pepsin, +/− external factors (NSAIDs, EtOH, other mucotoxic agents) or H. pyloriinfection
Pathology (Pediatr Rev 2001;22:349)
• Acid secretion is mediated by stimulation of parietal cells by acetylcholine (vagal), histamine, and gastrin (Zollinger–Ellison syndrome)
• H. pylori (gram-neg spiral rod) adapted to mucous layer; infxn possibly resulting in damage of intestinal mucosa 2/2 urease secretion (hydrolyzes urea to ammonia and bicarbonate) disrupts epithelial cell fxn; +/− vacuolating cytotoxin
• Non-H. pylori–related PUD on the rise, though ulcer disease in childhood still rare
Epidemiology (J Pediatr 2005;146:S21)
• H. pylori w/ ∼50% prevalence worldwide (from 10% [US avg] to 80% w/ higher rates in lower socioeconomic groups); only 10–15% infected develop PUD
• Evidence suggests acquisition of H. pylori infection occurs in childhood (by 5–10 yo)
• Often FHx of PUD w/ evidence of vertical transmission; (Helicobacter. 2011;Supp 1:59)
• Other etiologies less common overall (can be more prevalent in inpts); stress related (severe illness, burn), 2/2 ↑ ICP (Cushing ulcer) or 2/2 NSAID and other drugs
Clinical Manifestations (Pediatr Rev 2001;22:349)
• Generally p/w recurrent epigastric pain and can be assoc w/ postprandial or nocturnal abd pain, vomiting or food regurgitation
• In severe cases can present with failure to thrive, upper GI bleed, or chronic anemia
• Controversial whether H. pylori infxn can cause acute abd pain; NSAID- and drug-induced gastritis and ulcer formation can (Pediatrics 1999;103:192)
Diagnostics (J Pediatr 2005;146:S21; Helicobacter 2011;Supp 1:59)
• Initial eval w/ CBC diff (assess for anemia), ESR (IBD), LFTs, electrolytes (if recurrent vomiting), and stool evaluation for O and P (if exposure/diarrhea)
• If PUD suspected, send H. pyloriIgG; cannot distinguish btw current & prior infxn.
• Sens 54–94%, spec 59–97% (assay dependent); neither sens nor spec in children 2/2 lower titer cutoffs, shorter durations of infection
• Stool antigen testing is highly sensitive (98–100%) and specific (99–100%) when using locally validated cutoff points for a given population
• Urea breath testing (UBT): Radio-labeled urea ingested, then CO2 exhalation measured; good functional test and can be used to assess for cure. Sens 83.4%, Spec 99%
• Less widely used in children 2/2 concerns about radiation
• Can see false +, especially <3 yo, 2/2 discoordinated swallow (oral bacteria w/ urease too) Can see false neg if patient is already on Rx (acid suppression)
• Gold standard: Upper GI endoscopy and bx, radiographic UGI studies less sensitive
Treatment (J Pediatr Gastroenterol Nutr 2000;31:490)
• If H. pylori +; rx w/ PPI (1–2 mg/kg/d) w/ any 2 of the following: Amoxicillin 50 mg/kg/d, clarithromycin 15 mg/kg/d, and/or metronidazole 20 mg/kg/d
• Studies show 75–80% cure rate w/ 7 d of triple therapy, suggesting rx for 14 d
• Rx failure likely 2/2 abx resistance: Clarithro (18–35%), metro (15–20%)
Complications (J Pediatr 2005;146:S21)
• Atrophic gastritis +/− metaplasia; high risk if PPI use w/o eradication; gastric CA risk
• Gastric CA: 1% of H. pylori infected in adults; not reported in childhood
• Gastric mucosa-associated lymphoid tissue lymphoma (MALT): Rarer, only 0.1%