Biliary secretion of moxifloxacin in obstructive cholangitis and the non-obstructed biliary tract.

BACKGROUND

Biliary secretion of antibiotic agents into the bile is considerably compromised by biliary obstruction, a precondition of bacterial cholangitis. Moxifloxacin may be advantageous according to secretion and antimicrobial spectrum.

AIM

To establish the secretion of moxifloxacin into obstructed and non-obstructed bile.

METHODS

Biliary excretion of moxifloxacin was determined in plasma and bile of 10 patients with biliary obstruction and cholangitis and 10 patients without biliary obstruction 30 min after administration of 400 mg of moxifloxacin intravenously.

RESULTS

The plasma concentration of moxifloxacin was similar in both groups (4.45 +/- 1.58 microg/mL; 4.33 +/- 1.23 microg/mL). The concentration of moxifloxacin in the bile was significantly lower in patients with biliary obstruction than without (4.63 +/- 3.94 microg/mL; range 0.71-14.40; vs. 16.90 +/- 13.77 microg/mL; range 1.79-42.50; P = 0.043). Although significantly different, the penetration index was extensively high in those without biliary obstruction (4.41 +/- 4.40; range 0.35-14.45) but still sufficient in those patients with obstructive cholangitis (1.02 +/- 0.74; range 0.29-2.83; P = 0.035).

CONCLUSION

These findings are suggestive of an active secretion mechanism for moxifloxacin into the obstructed bile, producing a biliary concentration sufficiently above the minimal inhibitory concentrations for most of the expected bacteria.