Brief Article
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World J Gastroenterol. Dec 7, 2011; 17(45): 4979-4986
Published online Dec 7, 2011. doi: 10.3748/wjg.v17.i45.4979
13C-methacetin breath test reproducibility study reveals persistent CYP1A2 stimulation on repeat examinations
Anna Kasicka-Jonderko, Anna Nita, Krzysztof Jonderko, Magdalena Kamińska, Barbara Błońska-Fajfrowska
Anna Kasicka-Jonderko, Anna Nita, Krzysztof Jonderko, Magdalena Kamińska, Barbara Błońska-Fajfrowska, Department of Basic Biomedical Science, School of Pharmacy, Medical University of Silesia, PL-41-205 Sosnowiec, Poland
Author contributions: Kasicka-Jonderko A and Jonderko K designed the research, analysed the data and wrote the paper; Nita A and Kamińska M performed the research, collected and analysed the data; Błońska-Fajfrowska B was involved in providing financial support for this work and approved the final version.
Supported by The Medical University of Silesia, contracts No. NN-1-106-06, KNW-1-043/08 and KNW-1-154/09
Correspondence to: Dr. Anna Kasicka-Jonderko, Department of Basic Biomedical Science, School of Pharmacy, Medical University of Silesia, Kasztanowa street 3, PL-41-205 Sosnowiec, Poland. akj@sum.edu.pl
Telephone: +48-32-2699830 Fax: +48-32-2699833
Received: January 12, 2011
Revised: February 15, 2011
Accepted: February 22, 2011
Published online: December 7, 2011
Abstract

AIM: To find the most reproducible quantitative parameter of a standard 13C-methacetin breath test (13C-MBT).

METHODS: Twenty healthy volunteers (10 female, 10 male) underwent the 13C-MBT after intake of 75 mg 13C-methacetin p.o. on three occasions. Short- and medium-term reproducibility was assessed with paired examinations taken at an interval of 2 and 18 d (medians), respectively.

RESULTS: The reproducibility of the 1-h cumulative 13C recovery (AUC0-60), characterized by a coefficient of variation of 10%, appeared to be considerably better than the reproducibility of the maximum momentary 13C recovery or the time of reaching it. Remarkably, as opposed to the short gap between consecutive examinations, the capacity of the liver to handle 13C-methacetin increased slightly but statistically significantly when a repeat dose was administered after two to three weeks. Regarding the AUC0-60, the magnitude of this fixed bias amounted to 7.5%. Neither the time gap between the repeat examinations nor the gender of the subjects affected the 13C-MBT reproducibility.

CONCLUSION: 13C-MBT is most reproducibly quantified by the cumulative 13C recovery, but the exactitude thereof may be modestly affected by persistent stimulation of CYP1A2 on repeat examinations.

Keywords: 13C-Methacetin, Breath test, Isotope application in medicine, Liver, Reproducibility