Gastric Amyloidosis

  • Gastric amyloidosis is an abnormal protein folding and deposition disorder that has multiple etiologies and varied clinical manifestations.
  • It represents a significant diagnostic and treatment challenge.
  • Abdominal pain,  upper gastrointestinal bleeding, and symptoms related to altered motility are the common presentations.
  • Rarely, local amyloid tumor (gastric amyloidoma) can mimic malignancy endoscopically.
  • The diagnosis of amyloidosis requires a high index of suspicion, particularly in the elderly population, patients with chronic inflammatory diseases, hemodialysis patients, and patients with multiple myeloma.
  • In a study by Said et al. of 79 patients with biopsy-proven gastric amyloidosis, AL is by far the most common amyloid type affecting almost two-thirds of cases.
  • The gold standard for diagnosing amyloidosis is biopsy that shows deposition of pale eosinophilic acellular amorphous material involving the blood vessels and interstitium. These deposits are Congo red positive, produce apple green birefringence under polarized light and exhibit a bright red fluorescence under UV light illumination using Texas red filter.
  • Prognosis and treatment: The cornerstone of treatment and prognosis of amyloidosis is the treatment of the underlying disorder causing elevated amyloid precursors.

References

  • Said SM, Grogg KL, Smyrk TC. Gastric amyloidosis: clinicopathological correlations in 79 cases from a single institution. Hum Pathol. 2015;46:491-8.
  • Franck C, Venerito M, Weigt J, et al. Recurrent diffuse gastric bleeding as a leading symptom of gastrointestinal AL amyloidosis. Z Gastroenterol. 2017;55:1318-1322.