NOE Cohort and antibiotic therapy
Our results have shown that in our cohort of 63 patients, they have
received, on average, two different intravenous antibiotic regimes
(mean=2.1 courses). Over one third of patients (35%) receive three or
more intravenous courses. 63% of these changes are attributed to
significant adverse effects from high-dose intravenous antibiotics. This
does not include milder reactions or blood derangements that also
occurred but did not necessitate a change in antibiotic. There were 10
hospital admissions directly related to adverse effects from treatment.
4 due to severe acute kidney infection (AKI), 2 due to deranged LFTs, 2
due to progression of NOE, and 1 for adverse reaction and clostridium
difficile infection.
Recognised risk factors were prevalent in our cohort; with a mean age of
77, predominantly male (44 male, 19 female). 70% had diabetes with half
of this group taking insulin. These characteristics are similar to other
population studies (1)(13)(14). A Charlson Comorbidity Index score of 5
is significantly higher than the average population (15) and reflects
the general susceptibility this typical patient cohort has to developing
NOE.
The intravenous antibiotics used most were tazocin (45%) and
ceftazidime (25%). This is in line with other UK trusts; a survey on
NOE antibiotic selection showed comparable figures, where Tazocin was
used first-line in 41% of cases and ceftazidime in 7% (8). Similarly,
treatment duration was 80.1 days on average, or a median of 65 days
which better accounts for outliers. Although there is no agreed exact
duration within the literature, this length of treatment appears
consistent with other centres (9)(16). Therefore, both our cohort
attributes and antimicrobial management appear representative of the UK
NOE population.
We know that more medically complicated, multimorbid patients are likely
to require longer treatment (13). 6 of the 8 patients requiring 4 or 5
intravenous antibiotic regimes were admitted as an inpatient and/or were
treated with meropenem. The duration of treatment for those requiring
multiple different antibiotic regimes (mean= 97.7 days) was
significantly longer (p=0.024) than those treated successfully with one
course (61.1 days). Diabetes was statistically more prevalent in those
requiring multiple regimes. This may suggest that adverse effects of
treatment may more frequently affect those with comorbidities and
contribute to prolonged duration of treatment.