Carbapenems are active
beta-lactam antibiotics versus most of the gram positive and gram negative microorganisms and anaerobes although their activity is lacking in the case of Staphylococcus sp. resistant to
methicillin, Enterococcus faecium and Streptococcus pneumoniae with high resistance to
penicillin and some gram negative bacilli which naturally produce an methaloenzyme able to hydrolyze them such as Stenotrophomonas maltophilia.
Imipenem, the first synthetized
carbapenem requires administration with
cilastatin to avoid inactivation by renal dehydropeptidase 1.
Meropenem does not require being taken with the renal
enzyme inhibitor, with its activity being similar to that of
imipenem. In abdominal
infection the
carbapenems have shown to be the authentic monotherapy in this type of
infections being as effective as the different schedules of
antibiotic associations normally used. Treatment with
carbapenems in
bacterial meningitis should be currently limited to the cases produced by gram negative bacilli producers of wide spectrum
beta-lactamases (WSBL), cases of
meningitis by Pseudomonas aeruginosa or gram negative bacilli producers of inducible
cephalosporinase.
Meropenem is the
carbapenem of choice probably in these cases because the
carbapenems are often the only active
antibiotics and
meropenem, specifically, does not have the risk of convulsions observed with
imipenem-cilastatin. The
carbapenems have shown to be useful in skin and
soft tissue infections as well as in obstetric and gynecologic
infections as monotherapy similar to the schedules of the currently used
antibiotic associations. In the case of
nosocomial pneumonias, all the studies have evaluated the
carbapenems in monotherapy as useful and effective, specially in the case of
pneumonia by gram negative bacilli. Finally, in non filiated nosocomial
sepsis and specially in the case of neutropenic patients, the use of
carbapenems is particularly attractive in gram negative
sepsis in intensive care units. The appearance in the last few years of strains of gram negative bacilli, producers of wide spectrum
beta-lactamase or stable repressed hyperproducers of class I chromosomic
cephalosporinase, as well as other multiresistant gram negative bacilli, such as Acinetobacter baumanii make the
carbapenems, in many cases, the only effective
antibiotic in this type of
infections.