UMEM Educational Pearls

Category: Toxicology

Title: Scombroid

Keywords: scombroid, seafood (PubMed Search)

Posted: 5/27/2010 by Fermin Barrueto, MD (Updated: 3/26/2023)
Click here to contact Fermin Barrueto, MD

Scombroid is caused by ingestion of preformed histamine on skin of fish.

  • Naturally occurring histidine on scaly fish converted to histamine by surface bacteria - often fish left out too long, refrigeration will prevent the conversion.
  • Bacteria responsible are Morganelli morganii and K. pneumoniae
  • Fish: tuna, mahi mahi, amberjack, bonito, mackerel, albacore
  • Fish usually appears normal though meat may tast peppery
  • Patient presents minutes/hrs flushed, urticaria, HA, N/V
  • Self-limited and improve within hrs even without treatment
  • Antihistamines and rarley epinephrine will be needed