WRITER: AMY LILLARD
CONTACT: DAVE PEDERSEN
2130 Medical Laboratories
Iowa City IA 52242
(319) 335-8032; fax (319) 335-8034
Release: Feb. 1, 2000
UI College of Pharmacy researcher offers guidelines
on new antibiotics
IOWA CITY, Iowa -- A new class of antibiotics known
as fluoroquinolones can counter infections such as pneumonia, caused by penicillin-resistant
strains of a common pathogen. However, caution is necessary for doctors and
patients, according to a University of Iowa College of Pharmacy researcher.
Fluoroquinolones are a group of antibiotics increasingly
recognized for their ability to treat infections associated with the pathogen
Streptococcus pneumoniae. Michael Klepser, Pharm.D., assistant professor in
the UI College of Pharmacy, said treatments like fluoroquinolones are expanding
in importance as infections from Streptococcus pneumoniae become more resistant
to normal antibiotic treatment.
"The issue of resistance to penicillin is more and
more problematic," he said. "Streptococcus pneumoniae accounts for a variety
of infections affecting lots of people. If these strains are resistant to
penicillin, which they are at growing rates, they are often resistant to other
In an article published last November in the journal
Infectious Diseases in Clinical Practice, Klepser notes that penicillin became
the drug of choice to treat pneumonia and other infections caused by the pathogen
in the 1940s. Resistance to penicillin among all bacteria began to occur in
small numbers soon after its introduction, but increased to 22 percent of
all infections from streptococcus pneumoniae in the United States in the years
The infections associated with this pathogen, including
sinusitis and ear infections commonly contracted by children, are frequently
encountered, Klepser said. The growing prevalence of penicillin-resistant
infections is prompting clinicians and researchers to find other methods of
treatment like fluoroquinolones, which originated in the 1960s and were developed
into usable medications in the 1980s. Many clinicians are aware of these antibiotics
and treatment guidelines exist for their use, Klepser said, but some doctors
may not be fully aware of the amounts of resistance to penicillin that exist.
"Doctors probably need to be aware of the susceptibility-to-penicillin
patterns in the hospitals they work in and the community around them," he
said. "Prior to the 1990s, doctors could assume that penicillin would work
for patients. Now they need to know that high-level resistance can be up to
20 percent in some areas, so penicillin and related compounds will not work
The use of these fluoroquinolones, or other antibiotics
that can be substituted for penicillin, come at no small cost to the patient.
"Patients will probably have to pay for more expensive
antibiotics as resistance increases," Klepser said. "Clinicians try to start
treatment with the most narrow antibiotic activity, like penicillin. If this
fails, the patient goes back and gets another. If this fails, they need to
return again. The patient will need to pay for these return trips to the doctor,
and for more and more expensive treatments."
Fluoroquinolones show signs of working more effectively
in overcoming various degrees of antibiotic resistance in the infections.
Klepser stresses, however, that they should not be used as a first line of
treatment unless in situations of penicillin allergy, high likelihood of penicillin
resistance or deteriorating patient condition.
This caution is necessary because of side effects
and some tendency to interact badly with specific medications. In addition,
physicians should approach this treatment responsibly and realize the possibility
"It would be irresponsible to use these potent antibiotics
and not take into account the fact that some reports of resistance to the
fluoroquinolones has emerged," he said. "The useful life of an antibiotic
is not infinite and is often dictated by how frequently the drug is used.
It appears that resistance may occur more rapidly if an antibiotic is used