Introduction
Cystic fibrosis (CF) is the most common life-limiting autosomal
recessive disease in Caucasian populations. Thickened mucous secretion
caused by the mutations on the CFTR gene leads to obstruction in the
bronchioles secondary to mucus plugging. This causes an optimal
environment for bacterial growth and infection1. Chronic pulmonary
infection damaging the lung parenchyma and decreasing the pulmonary
function is the leading cause of mortality and morbidity in individuals
with CF 2-4. The most
common microorganisms isolated from respiratory secretions in CF areStaphylococcus aureus (S. aureus) and Pseudomonas
aeruginosa (P. aeruginosa)4.
Chronic infection of P. aeruginosa is associated with more
parenchymal damage, a more rapid decline in lung function, and earlier
mortality 2;
5. The acquisition ofMethicillin-resistant S. aureus (MRSA), even though that is not
seen as much as P. aeruginosa , causes a decline in forced
expiratory volume in 1-second percent predicted (FEV1pp)
and associated with worse survival6;
7. Current guidelines recommend
antibiotic eradication treatment for MRSA and P. aeruginosa to
prevent lung damage and chronic infections8;
9.
The antibiotic eradication treatment for P. aeruginosa and MRSA
is an established standard of care worldwide9-13. However, the most
effective route of administration of antibiotics (oral, inhalation or
intravenous (IV)) and choice of antibiotic regimen are not clear. The
two Cochrane reviews on this matter state that there is still
insufficient data to decide on which antibiotic strategy should be used
for the eradication of early P. aeruginosa or MRSA in CF14;
15.
There are numerous randomized controlled trials (RCT) on comparing
different oral antibiotic regimens, oral vs. inhalation regimens and
oral/inhalation combination regimens for P. aeruginosaeradication 14. While
there are many retrospective studies comparing inhalation and oral
antibiotic regimens, there are only two RCTs for MRSA eradication15. On the other hand,
there are few studies comparing IV vs. oral/inhalation antibiotic
regimens. To date, there is only one RCT comparing IV and non-parenteral
antibiotics for the eradication of P. aeruginosa and there have
been no published data that investigate the efficacy of IV compared to
non-parenteral antibiotics to eradicate MRSA16.
Today, many CF clinics use IV antibiotics as antibiotic eradication
treatment. IV eradication regimen requires hospital admission, IV access
which might be traumatic and may worsen patient’s health-related quality
of life (HRQoL) 17.
Additionally, IV eradication regimens increase health-care costs
significantly 16. In
this study, we investigate the efficacy of IV vs. non-IV (oral and/or
inhalation) antibiotic eradication treatments for the eradication of the
first isolation of P. aeruginosa and MRSA in individuals with CF.
Additionally, we aim to determine clinical variables associated with
chronic infection of P. aeruginosa and MRSA.