Multidrug-Resistant Urinary Tract Isolates of Escherichia coli: Prevalence and Patient Demographics in the United States in 2000

Abstract

Concurrent resistance to antimicrobials of different structural classes has arisen in a multitude of bacterial species and may complicate the therapeutic management of infections, including those of the urinary tract. To assess the current breadth of multidrug resistance among urinary isolates of Escherichia coli, the most prevalent pathogen contributing to these infections, all pertinent results in The Surveillance Network Database-USA from 1 January to 30 September 2000 were analyzed. Results were available for 38,835 urinary isolates of E. coli that had been tested against ampicillin, cephalothin, ciprofloxacin, nitrofurantoin, and trimethoprim-sulfamethoxazole. Of these isolates, 7.1% (2,763 of 38,835) were resistant to three or more agents and considered multidrug resistant. Among the multidrug-resistant isolates, 97.8% were resistant to ampicillin, 92.8% were resistant to trimethoprim-sulfamethoxazole, 86.6% were resistant to cephalothin, 38.8% were resistant to ciprofloxacin, and 7.7% were resistant to nitrofurantoin. The predominant phenotype among multidrug-resistant isolates (57.9%; 1,600 of 2,793) included resistance to ampicillin, cephalothin, and trimethoprim-sulfamethoxazole. This was the most common phenotype regardless of patient age, gender, or inpatient-outpatient status and in eight of the nine U.S. Bureau of the Census regions. Rates of multidrug resistance were demonstrated to be higher among males (10.4%) than females (6.6%), among patients >65 years of age (8.7%) than patients <17 (6.8%) and 18 to 65 (6.1%) years of age, and among inpatients (7.6%) than outpatients (6.9%). Regionally, the rates ranged from 4.3% in the West North Central region to 9.2% in the West South Central region. Given the current prevalence of multidrug resistance among urinary tract isolates of E. coli in the United States (7.1%), continued local, regional, and national surveillance is warranted.

Prevalence of class 1 and 2 integrons among the multidrug resistant uropathogenic strains of Escherichia coli

“…Multidrug resistance in the United States was 7.1% in 2000 [16] and in Spain it was 17.1% and increased by 50% between 2001 and 2003 [13]. The rate of MDR in the study of Mansouri et al for enteric bacteria in the pediatric wards of regional hospitals was 23.4% (16). Japoni et al have reported that 82.5% of their E. coli isolates showed a MDR phenotype [1].…”

Asymptomatic bacteriuria and symptomatic urinary tract infections in pregnancy

“…One meta-analysis of four trials reported a non significant pooled odds ratio of any fetal malformation with nitrofurantoin of 1·29 (95% CI 0·25-6·57), although the number and quality of the studies included are limited [80]. There is a low level of resistance to nitrofurantoin among uropathogens with NCCLS data from 2000 reporting only a rate of 1% [81].…”

Urinary Tract Infections During Pregnancy

“…Nitrofurantoin only achieves therapeutic levels in the urine, so it cannot be used to treat pyelonephritis. This drug is not active against Proteus spp (Christensen, 2000;Sahm et al, 2001). There is a theoretical risk of nitrofurantoin-induced hemolytic anemia in the fetusor newborn, particularly in those with glucose-6-phosphate dehydrogenase (G6PD) deficiency (Smaill & Vazquez, 2007;Guinto et al, 2010).…”