A consensus statement on the use of antibiotics against Pseudomonas aeruginosa
in patients with cystic fibrosis (CF) has been published this month.
The extent to which anti-pseudomonal therapy affects survival is unknown but
therapy is warranted in CF patients, the document says. It does not recommend
preventive antibiotic therapies against P aeruginosa, because of a lack of evidence,
but suggests that early treatment of initial P aeruginosa colonisation could
delay the onset of chronic P aeruginosa infection. The document includes a table
of recommended doses of antibacterial agents for P aeruginosa infection in patients
with CF which, it notes, might differ from regulatory authority approved doses.
Mr Andrew Whitehead (lead adult cystic fibrosis pharmacist, Leeds Teaching Hospitals
NHS trust) told The Journal on October 17 that the consensus was useful. It
had resulted in a summary of current knowledge which, importantly, classified
points as either evidence-based or current best practice. The table of recommended
antibiotic doses was of particular importance for pharmacists, he said, as was
a section on intravenous antipseudomonal antibiotic therapy.
The document says that in general, high doses of antibiotics should be used
to maximise drug concentration in the lungs and to minimise the risk of development
of bacterial resistance. Combination therapy delays resistance compared with
monotherapy, it says. Monotherapy may be as effective as combination therapy
against a susceptible bacterial strain, but, with resistant strains, combination
therapy is more effective, it adds.
In terms of maintenance therapy, patients with chronic P aeruginosa infection
should be treated with antibiotics with specific anti-P aeruginosa activity,
either intravenously three to four times a year or by aerosol administration
(using colistin or tobramycin) throughout the year, the document says.
It recommends the inhalation route for maintenance therapy and intravenous administration
for moderate to severe acute exacerbations. Oral ciprofloxacin might also be
appropriate for exacerbations. Nebulised antibiotic therapy is clinically effective
but its major side effect is bronchospasm, it says. Nebulisation times should
be kept short to encourage compliance.
The consensus was reached following a European consensus conference involving
34 European experts, which took place in Tuscany, Italy, in November, 1999.
It is published in the European Respiratory Journal (2000;16:1).