Bezoars

Basics

Description

  • Accumulation of foreign material in the gastrointestinal (GI) tract
  • Commonly divided into three categories based on the substances from which the bezoar is derived:
    • Phytobezoar (from vegetables/fruits)
    • Trichobezoar (hair)
    • Lactobezoar (milk/formula)
  • Documented to occur in humans for >2 millennia, suggesting formation of bezoars may have been/still be culturally important for certain societies

Epidemiology

  • Phytobezoars occur almost exclusively in adults.
  • 90% of trichobezoars occur in female patients <20 years of age.
  • Lactobezoars occur mostly in premature, low-birth-weight infants.

Pathophysiology

  • Trichobezoars
    • Associated with developmental delay, pica, trichotillomania, and trichophagia; may ingest own hair but also rugs and animal or doll hair
    • Most cases of trichophagia do not result in bezoar formation (~1%).
    • History of trichophagia is obtained in only 50% of cases.
    • Retention and accumulation of hair strands in the gastric folds
    • Trichobezoars may become large and form a cast in the stomach leading to abdominal mass.
    • Bezoar may extend through the pylorus into the small bowel. This phenomenon is commonly referred to as Rapunzel syndrome. The “tail” may obstruct the ampulla of Vater, leading to jaundice and pancreatitis.
  • Phytobezoars
    • Most common form among adults, rare in children
    • Associated with gastric dysmotility and poor gastric emptying (either primary or following gastric surgery) and hypochlorhydria
    • Composed primarily of cellulose, hemicellulose, lignins, and tannins
  • Lactobezoars (milk)
    • Most often reported in premature, low-birth-weight infants being fed high-calorie premature formula (although there are reports in full-term infants and exclusively breastfed infants)
    • Factors contributing to lactobezoar formation include the following:
      • Formulas with high casein content
      • Early and rapid feeding advancement in small infants
      • High-caloric-density formulas
      • Formulas with high calcium/phosphate content
      • Continuous tube feedings
      • Altered gastric motility in low-birth-weight infants

Etiology

Classification of bezoars is dependent on the most prominent substance from which they are formed, including:

  • Trichobezoars: hair, carpet
  • Phytobezoars: indigestible fruit and vegetable matter
  • Lactobezoars: milk
  • Less common materials include the following:
    • Foreign bodies
    • Gallstones
    • Medications, including vitamins, antacids, psyllium, sucralfate, cimetidine, and nifedipine
  • Can occur in cystic fibrosis (CF) patients after lung transplantation
  • Colonic and rectal bezoars
    • Due to indigestible sunflower seeds, popcorn, and chewing gum have been reported in children and adults
    • These usually present with obstruction, although encopresis and colitis-type symptoms have been described.

Commonly Associated Conditions

  • Iron deficiency anemia
  • Steatorrhea
  • Protein-losing enteropathy

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