Resistance to many commonly used an...

Resistance to many commonly used antibiotics has been steadily increasing for years. The Tracking Resistance in the United States Today (TRUST) surveillance program has been tracking this puzzle annually since 1998. Karlowsky and colleagues not away the results of the 2001-2002 TRUST review and delineate clinical factors associated with pneumococcal antibiotic resistance.

This contemplate obtained 7,671 isolates of Streptococcus pneumoniae from 239 participating hospital laboratories quite through the United States. Antibiotic resistance was defined according to the minimum inhibitory concentrations (MICs) settle for the medications by the National Committee for Clinical Laboratory Standards.

Comparing the 1998-99 respiratory infection season with the 2001-02 season, pneumococcal isolates resistant to penicillin increased from 147 to 184 percent The greatest overall increase in MIC for an antibiotic occurr with azithromycin, which increased in the overall prevalence of resistance from 227 to 275 percent Pneumococcal susceptibility to trimethoprim-sulfamethoxazole (TMP-SMX) improved slightly, with a pendant in the resistance rate from 273 to 260 percent soft resistance rates were still reported for ceftriaxone (range: 16 to 25 percent athwart the four years of data) and levofloxacin (slowly rising from 05 to 09 percent)

Resistance rates in isolates from patients younger than 18 years were consistently higher for all antibiotics excluding levofloxacin, which is typically not used in children. Isolates obtained from lower respiratory tract sites were more likely to demonstrate resistance than descendants culture samples. Co-resistance to other antibiotics was associated eagerly with penicillin resistance, especially for azithromycin (763 percent of penicillin-resistant isolates also were resistant to this macrolide) and TMP-SMX (873 percent co-resistance). Ceftriaxone co-resistance was 91 percent and a hardly any isolates were resistant to as well-as; not only-but also; not only-but; not alone-but penicillin and levofloxacin (1.3 percent)

Antibiotic resistance varied somewhat by dint of region. Isolates from the West southern Central census region (Texas, Oklahoma, Arkansas, Louisiana) were the chiefly likely to demonstrate resistance, while those from the strange England area had the lowest rates of resistance. The variation in resistance rates across regions was widest for TMP-SMX (differences as great as 219 percent among areas during the four years of surveillance). The least variation was noted with levofloxacin (only 05 to 19 percent differences during the four years of surveillance).

The authors end that pneumococcal antibiotic resistance rates across the nation have steadily climbed, from 1998 to 2002 for penicillin and azithromycin. in the greatest degree isolates remain sensitive to ceftriaxone and levofloxacin. Younger patients and those with penicillin-resistant isolates are more likely to have pneumococcal infections caused according to multi--drug-resistant organisms.

Bill Zepf MD

Karlowsky JA, et al. Factors associated with relative rates of antimicrobial resistance among Streptococcus pneumoniae in the United States: accrues from the TRUST surveillance program (1998-2002) Clin Infect Dis April 15 2003;36:963-70

COPYRIGHT 2003 American Academy of Family Physicians

COPYRIGHT 2003 Gale Group