What is the prevalence of multidrug‑resistant (MDR) and extensively drug‑resistant (XDR) uropathogenic Escherichia coli, including regional variations?

Prevalence of MDR and XDR Uropathogenic E. coli

The prevalence of multidrug-resistant (MDR) uropathogenic E. coli ranges from 57% to 78% across different regions, with particularly high rates in the Middle East, while XDR strains remain less well-defined but carbapenem resistance is emerging as a critical concern.

Global and Regional MDR Prevalence

Middle Eastern Regions Show Highest Rates

• Jordan demonstrates 57.3% MDR prevalence among uropathogenic E. coli isolates, with hospitalized patients showing significantly higher rates than outpatients 1

• Iran reports 61-68% MDR prevalence, with inpatients at 68% and outpatients at 61%, representing resistance to at least three drug classes including aminoglycosides, fluoroquinolones, penicillins, cephalosporins, or carbapenems 2

• Southern Iran shows even higher rates at 93.6% MDR among all E. coli isolates, with 96.3% of ESBL-producing strains being multidrug-resistant 3

• Uganda reports 78% MDR prevalence among uropathogenic E. coli clinical isolates, with high association to biofilm formation 4

ESBL-Producing Strains Drive Resistance

• ESBL-positive strains account for 34.6% of uropathogenic E. coli in southern Iran, with nearly all (96.3%) being MDR 3

• Among ESBL-producers, 100% harbor blaCTX-M genes, 63% carry blaSHV, and 11.1% possess blaTEM genes 3

• Jordan shows 78% positivity for CTX-M-15 genes and 76% for CTX-M-1 among MDR isolates, with 100% carrying the high-risk ST131 clone 1

Emerging XDR and Carbapenem Resistance

Carbapenemase Genes Signal XDR Emergence

• Saudi Arabia reports presence of NDM-1, NDM-5, and OXA-181 carbapenemases in uropathogenic E. coli from community-acquired UTIs, representing extensively drug-resistant phenotypes 5

• These carbapenem-resistant strains include globally predominant MDR clones ST131 and ST69, as well as ST410 and ST448 carrying multiple β-lactamase genes 5

• Jordan shows minimal carbapenemase presence with all 50 tested MDR isolates negative for blaIMP, blaVIM, blaNDM-1, and blaOXA-48, except one isolate positive for blaKPC-2 1

• Iran reports zero resistance to meropenem in both outpatient and inpatient populations, suggesting carbapenem resistance remains uncommon in that region 2

Resistance Patterns by Antibiotic Class

First-Line Antibiotics Show Alarming Failure Rates

• Ampicillin, ceftazidime, nalidixic acid, and trimethoprim-sulfamethoxazole exceed 50% resistance in Iranian isolates 2

• Trimethoprim-sulfamethoxazole and amoxicillin show 93% resistance in Ugandan isolates, followed by gentamicin at 87% 4

• All isolates in southern Iran were resistant to tested penicillins, with resistance to two-thirds of tested antibiotics exceeding 50% 3

Remaining Effective Agents

• Nitrofurantoin maintains <20% resistance and remains the most appropriate empiric option for ESBL-producing uropathogenic E. coli 3

• Amikacin (89.1% sensitivity), nitrofurantoin (85.9%), and gentamicin (82.4%) show markedly greater activity than other antimicrobials in Iran 2

• Imipenem shows only 0.5% resistance in Ugandan isolates 4

Clinical Implications and Risk Factors

Hospital vs. Community Settings

• Hospitalized patients demonstrate significantly higher MDR rates compared to outpatients across multiple studies 1, 2

• Community-acquired UTIs in Saudi Arabia harbor carbapenem-resistant clones, indicating spread beyond healthcare settings 5

Virulence Gene Co-occurrence

• 100% of MDR isolates in Jordan carry mutated parC and gyrA genes conferring fluoroquinolone resistance, along with ST131 clone positivity 1

• Biofilm formation occurs in 62.5% of uropathogenic E. coli, with strong association to MDR phenotype (78% of biofilm formers are MDR) 4