Impact Of Antibiotic Resistance Research Articles

Management of Antimicrobials in Infectious Diseases: Impact of Antibiotic Resistance

Management of Antimicrobials in Infectious Diseases: Impact of Antibiotic Resistance

Management of Antimicrobials in Infectious Diseases: Impact of Antibiotic Resistance

Management of Antimicrobials in Infectious Diseases: Impact of Antibiotic Resistance

Impact of antibiotic resistance on clinical outcomes and the cost of care.

Antibiotic-resistant organisms are common in intensive care unit infection and can be either Gram-positive or Gram-negative. A number of studies have evaluated whether these organisms can lead to excess morbidity, mortality, or cost. In general, the studies are confounded by a number of methodologic issues, including the selection of an appropriate control population. Cases and controls must be appropriately matched for the presence of infection, the presence of infection with similar organisms (but ones that are either antibiotic-sensitive or -resistant), and severity of illness. In addition, studies must account for the therapies given to patients who are infected with resistant organisms because resistance is an important risk factor for inadequate empirical therapy, and such therapy is itself a potent determinant of a number of adverse outcomes, including mortality. To date, the data with methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococcus are inconsistent with regard to the effect on mortality rates, although infection with both organisms can lead to excess length of stay and increased cost of care. When studies have been adequately controlled and powered, infection with vancomycin-resistant enterococcus has had more of an effect on the mortality rate than infection with antibiotic-sensitive enterococci. Infection with resistant Gram-negatives also has adverse impact on outcome, with excess mortality being seen in patient groups infected with Acinetobacter and Pseudomonas aeruginosa. If we are to minimize the effect of resistance on medical outcomes and cost, it will be necessary to have a current knowledge of each intensive care unit's pathogens and susceptibility patterns, so that empirical therapy will have a good likelihood of being effective. In addition, new therapeutic agents may improve on the efficacy of older agents and could reduce cost if they allow for some patients to leave the hospital and to finish therapy with an oral formulation of a highly bioavailable agent.

Management of Antimicrobials in Infectious Diseases: The Impact of Antibiotic Resistance Edited by Arch G. Mainous III, PhD and Claire Pomeroy, MD. Totowa, NJ: Humana Press, 2001. 368 pp., illustrated. $99.50

Management of Antimicrobials in Infectious Diseases: The Impact of Antibiotic Resistance Edited by Arch G. Mainous III, PhD and Claire Pomeroy, MD. Totowa, NJ: Humana Press, 2001. 368 pp., illustrated. $99.50

Impact of Antibiotic Resistance on the Treatment of Gram-negative Sepsis.

Resistance among gram-negative organisms has greatly complicated the care of the septic patient. An understanding of the likely source of infection, the epidemiologic risk of the patient being exposed to an antibiotic-resistant organism, and the specific vulnerabilities of the host are essential to the proper selection of empiric antimicrobial therapy. In this report, we discuss the epidemiology, antibiotic resistance mechanisms, microbiology, treatment strategies, and diagnostic and therapeutic innovations in the approach to the septic patient.

Pneumococcal mastoiditis in children.

To determine the impact of antibiotic resistance on the frequency, clinical features, and management/outcome of mastoiditis attributable to Streptococcus pneumoniae. Retrospective review of the medical records of children with mastoiditis caused by S pneumoniae from September 1993 through December 1998. Infants and children with pneumococcal mastoiditis cared for at 8 children's hospitals in the United States. Thirty-four children with pneumococcal mastoiditis were identified. The median age of the children was 12 months (range: 2 months-12.5 years); 28 (82%) were </=2 years old. Six children had recurrent otitis media. A subperiosteal abscess was noted in 13 children (37%). The mastoids were abnormal in all 25 patients on whom computed tomography was performed. There was no trend toward increasing numbers of cases per year despite increasing proportions of pneumococcal isolates, which were nonsusceptible to penicillin. Serogroup 19 accounted for 57% of isolates, serogroup 23 for 14.3% of isolates, and serotype 3 for 10. 7% of isolates. Except for receipt of less antibiotic therapy in the previous 30 days, children with penicillin-susceptible isolates had similar demographic features and clinical findings and surgical treatment as did children whose isolates were nonsusceptible to penicillin. Pneumococcal mastoiditis occurs primarily in children <2 years of age and usually is not associated with a history of recurrent otitis media. The number of cases of mastoiditis caused by S pneumoniae occurring among 8 children's hospitals has remained stable despite increasing rates of antibiotic-resistant S pneumoniae. Serogroup 19 is the leading serogroup associated with pneumococcal mastoiditis. Streptococcus pneumoniae, mastoiditis, serotypes, resistance.

Acute otitis media in the 1990s: the impact of antibiotic resistance.

Acute otitis media in the 1990s: the impact of antibiotic resistance.

Impact of antibiotic resistance on chemotherapy for pneumococcal infections.

Over the past three decades, penicillin-resistant pneumococci have emerged worldwide. In addition, penicillin-resistant strains have also decreased susceptibility to other beta-lactams (including cephalosporins) and these strains are often resistant to other antibiotic groups, making the treatment options much more difficult. Nevertheless, the present in vitro definitions of resistance to penicillin and cephalosporins in pneumococci could not be appropriated for all types of pneumococcal infections. Thus, current levels of resistance to penicillin and cephalosporin seem to have little, if any, clinical relevance in nonmeningeal infections (e.g., pneumonia or bacteremia). On the contrary, numerous clinical failures have been reported in patients with pneumococcal meningitis caused by strains with MICs > or = 0.12 microg/ml, and penicillin should never be used in pneumococcal meningitis except when the strain is known to be fully susceptible to this drug. Today, therapy for pneumococcal meningitis should mainly be selected on the basis of susceptibility to cephalosporins, and most patients may currently be treated with high-dose cefotaxime (+/-) vancomycin, depending on the levels of resistance in the patient's geographic area. In this review, we present a practical approach, based on current levels of antibiotic resistance, for treating the most prevalent pneumococcal infections. However, it should be emphasized that the most appropriate antibiotic therapy for infections caused by resistant pneumococci remains controversial, and comparative, randomized studies are urgently needed to clarify the best antibiotic therapy for these infections.

Pneumonia: the impact of antibiotic resistance on its management.

Pneumonia in the community affects between 1 and 5 per 1000 per year. The microbial aetiology is diverse and influenced by preexisting disease, seasonality, as well as animate and inanimate environmental sources; pneumococci, Legionella spp., Mycoplasma pneumoniae, and more recently Chlamydia pneumoniae are the predominant bacterial pathogens. Gram-negative enteric bacteria although less common are particularly virulent. Antibiotic resistance is well established for Haemophilus influenzae and Gram-negative bacillary infections, but has been a recent phenomenon in the case of Streptococcus pneumoniae, which is numerically the leading pathogen. Despite the concerns raised by this reduced susceptibility to penicillin, evidence that this has been translated into increased clinical failures is currently difficult to establish. Macrolide and tetracycline resistance among pneumococci is more common. beta-Lactamase production by H. influenzae has now reached levels where, in those with severe pneumonia, beta-lactamase stable agents are preferred. Consensus Guidelines on the treatment of community acquired pneumonia have been published by the British Thoracic Society, the American Thoracic Society, and from Expert Panels in Canada and France. These emphasize severity assessment and differentiate management in the community or hospital setting. The recommended regimens are compared and contrasted. In conclusion, mild/moderate pneumonia, when pneumococcal in nature, is likely to still respond to amoxycillin or penicillin G, but in higher dosages where pneumococcal resistance is documented. However, in severe infection where pneumococcal resistance, other beta-lactamase-producing pathogens, or an atypical infection could be operating, it is important that initial empirical therapy be broad spectrum and promptly administered. Treating multiresistant pneumococcal disease in those allergic to beta-lactams presents a particular dilemma. Glycopeptides are currently preferred.

The clinical impact of antibiotic resistance.

The clinical impact of antibiotic resistance.