[Clinical relevance of N-acetyltransferase type 2 (NAT2) genetic polymorphism].

Polymorphic N-acetyltransferase (NAT2) is involved in the metabolism of several compounds relevant in pharmacology or toxicology, with diverse clinical consequences. Inter-ethnic variations in distribution of the acetylation phenotype are significant. The caffeine test is most often used to assess the acetylation phenotype and to identify rapid and slow acetylators.

[The acetylator polymorphism in a Khmer population: clinical consequences].

The great variability of slow acetylator (SA) and/or rapid acetylator (RA) frequency is mainly due to ethnic-racial origin. Using the urinary elimination ratio of three metabolites of caffeine--acetylamino formylamino methyluracil (AFMU) to AFMU + 1-methyl urate (1U) + 1-methyl xanthine (1X)--we settled the acetylation phenotype in 54 independent subjects of Khmer and 70 independent subjects of Caucasian origin. Using DNA from peripheral leucocytes, we determined by PCR, in 32 Khmer and 122 Caucasian subjects, the frequencies of wild-type alleles (NAT-2 *4) and of mutated alleles (NAT-2 *5A, *6A, *7A).

Caffeine metabolism before and after liver transplantation.

Aim: To study drug metabolism in patients before and after liver transplantation using caffeine as a probe drug. Forty-five patients undergoing liver transplantation for various liver diseases and who had well documented dossiers were selected for the study. Before the liver transplantation and 1 month, 1 year, and 6 years after liver transplantation, they were given 200 mg of caffeine by the oral route in the morning after voiding their bladder.

Caffeine metabolism in a group of 67 patients with primary biliary cirrhosis.

Objective: To evaluate the polygenic regulated caffeine metabolism in a group of 67 patients with a documented primary biliary cirrhosis (PBC) classified according to the histologic stage proposed by Scheuer.

Methods: Over a 14-year period, drug liver metabolism, using caffeine as a probe drug, has been systematically carried out in addition to the usual clinical, histological and biochemical investigations performed in patients with PBC. The "Caffeine test" consisted of a 200 mg caffeine oral intake.

Caffeine metabolism differences in acute hepatitis of viral and drug origin.

The 24-h urinary excretion rate of caffeine metabolites following 200 mg caffeine intake has been proved to be a valuable safe quantitative test of liver function. The pathological mechanism of acute hepatitis of viral and drug origin is different. In both diseases, the patient's caffeine metabolic capacity during the acute and the recovery period was compared.