- Last Update On : 2013-11-25
Trimethylaminuria is an syndrome characterized by excretion of excessive amounts of unoxidized trimethylamine in the urine, breath, sweat, and reproductive fluids. Trimethylamine is extremely volatile and has a pungent ammonia-like odor resembling rotten fish. For this reason, trimethylaminuria is commonly referred to as Fish Odor Syndrome. No other physical symptoms are associated with trimethylaminuria.
Trimethylamine is a volatile, malodorous chemical derived from dietary substances such as choline by bacteria in the GI tract. Trimethylamine is normally metabolized to the nonvolatile chemical , trimethylamine-N oxide, by the liver enzyme flavin-containing monooxygenase 3 (FMO3).
Trimethylaminuria can be caused by either a congenital deficiency of FMO3 or excess production of TMA in the GI tract. Acquired trimethylaminuria may occur de novo during adulthood in patients with liver disease. Impaired hepatocellular function or portosystemic shunts are believed t