Failure of oral antibiotic therapy after bariatric surgery
Roy et al. investigated the association between the history of RYGB and
increased treatment failure in patients who received oral antibiotics53. Treatment failure was defined as any prescription
change that resulted in an increased daily dose, frequency or duration
of current oral antibiotics, substitution or addition of another oral,
intramuscular, or intravenous antibiotic for the same indication, any
surgical intervention for current infection, emergency room or
outpatient visit for current infection and hospitalization for current
infection. In their study, 186 patients were included (58 RYGB patients
and 128 controls). There was no significant difference in composite
therapeutic failure rates by time since RYGB surgery (24.1%, n=14)
compared to the control group (15.6% n=20). However, in the subgroup
treated with fluoroquinolones (31.6 vs. 7.1 %, n= 6 and 2 respectively)
and with sulfamethoxazole/trimethoprim (40 vs. 7.1%, n=4 and 2
respectively) more therapeutic failure rates were reported compared to
controls.
Summarizing, for beta-lactam antibiotics, similar, increased or
decreased exposure can be anticipated after surgery, however as
concentrations seem overall high enough, these antibiotics can generally
be applied. For macrolide antibiotics, a reduced exposure up to 30-40%
after surgery has been reported and therefore the use of these
antibiotics should be discouraged. While fluoroquinolones did show some
reduction in exposure after surgery, the overall bioavailability seems
adequate. In general, it seems that bariatric surgery patients treated
with oral antibiotics should be monitored closely for therapy failure
and side effects. When prescribing antibiotics to bariatric surgery
patients, several factors should be considered including , the site and
severity of infection, route of administration and potential toxicity.