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