Trimethylaminuria, fish odour syndrome: a new method of detection and response to treatment with metronidazole.

Trimethylaminuria is an autosomal recessive disorder involving deficient N-oxidation of the dietary-derived amine trimethylamine (TMA). TMA, a volatile tertiary amine, accumulates and is excreted in urine of patients with deficient TMA oxidase activity. Treatment strategies for this condition are limited. We report a new stable-isotope dilution method for rapid sequential analysis of TMA concentrations and the clinical and biochemical response to treatment with metronidazole.