The C-caffeine breath test distinguishes significant fibrosis in chronic hepatitis B and reflects response to lamivudine therapy.
BACKGROUND
The 13C-caffeine breath test is a non-invasive, quantitative test of liver function.


OBJECTIVE
To determine the utility of the 13C-caffeine breath test in chronic hepatitis B virus and its ability to monitor response to lamivudine.


METHODS
Forty-eight chronic hepatitis B virus patients and 24 controls underwent the 13C-caffeine breath test. In 28 patients commenced on lamivudine, 13C-caffeine breath tests were performed at 1 week (n = 12) and after 1 year of therapy.


RESULTS
Patients with Metavir F0-1 fibrosis (2.30 +/- 1.02 Delta per thousand per 100 mg caffeine) had a 13C-caffeine breath test similar to controls (2.31 +/- 0.85, P = 0.96). However, patients with F2-3 fibrosis (1.59 +/- 0.78, P = 0.047) and cirrhotic patients (0.99 +/- 0.33, P = 0.001) had a decreased 13C-caffeine breath test. Fibrosis correlated best with the 13C-caffeine breath test (r(s) = -0.62, P < 0.001). The 13C-caffeine breath test independently predicted significant (F > or = 2) and advanced (F > or = 3) fibrosis and yielded the greatest area under the receiver operating characteristic curve (0.91 +/- 0.04) for predicting advanced fibrosis. The 13C-caffeine breath test was unaltered by 1 week of lamivudine but improved by 61% (P < 0.001) in responders to long-term lamivudine, whereas in those with viraemia and elevated alanine aminotransferase, values remained stable or deteriorated.


CONCLUSIONS
The 13C-caffeine breath test distinguishes chronic hepatitis B virus-related fibrosis and detects improvement in liver function in response to long-term lamivudine.
Park
G J-H
GJ
Department of Gastroenterology and Hepatology, The University of Sydney, Concord Hospital, Concord, NSW, Australia. gpark@med.usyd.edu.au
Katelaris
P H
PH
Jones
D B
DB
Seow
F
F
Lin
B P C
BP
Le Couteur
D G
DG
Ngu
M C
MC
D000328:Adult; D001944:Breath Tests / Q000379:methods*; D002110:Caffeine / Q000032:analysis*; D005260:Female; D019694:Hepatitis B, Chronic / Q000188:drug therapy* / Q000473:pathology; D006801:Humans; D019259:Lamivudine / Q000627:therapeutic use*; D008103:Liver Cirrhosis / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D018894:Reverse Transcriptase Inhibitors / Q000627:therapeutic use*; D016896:Treatment Outcome
D018894:Reverse Transcriptase Inhibitors; D019259:Lamivudine; D002110:Caffeine