Prevalence of Multidrug-Resistant UPEC in India
Multidrug resistance (MDR) in uropathogenic E. coli is alarmingly high in India, affecting 52.8% to over 75% of community-acquired isolates, with significant regional variation and concerning rates of ESBL production (44.8-54%) and emerging carbapenem resistance (4.3-5.1%).1, 2
National MDR Burden
The prevalence of multidrug-resistant UPEC in India represents a critical public health challenge:
Community-acquired infections show MDR rates exceeding 75% in recent molecular studies from suburban areas, with multiple-antibiotic resistance (MAR) index >0.2 in the majority of isolates 2
ESBL production is documented in 44.8-54% of community-acquired UPEC isolates nationally, with the highest rates (52.8%) specifically among E. coli 3, 1
Carbapenem resistance has emerged at 4.3-5.1% of community isolates, including NDM-5-producing strains and OXA-48 co-harboring isolates, representing a concerning trend 1, 2
Regional Variations
Geographic disparities in resistance patterns are substantial across India:
The heavily populated Gangetic plains (north and northwest India) demonstrate significantly higher resistance rates compared to other regions 3
South, West, and Northeast India maintain relatively better susceptibility profiles, though still concerning 3
One Delhi center recorded only 42% meropenem susceptibility, highlighting extreme regional variation even for last-line agents 3
Resistance Patterns to Common Antibiotics
The antibiotic susceptibility landscape reveals severe limitations for empiric therapy:
Fluoroquinolones retain only 31% susceptibility nationally, with >80% of isolates showing resistance in some studies 3, 2
Oral cephalosporins show only 26% susceptibility, with third-generation cephalosporins at 46% and fourth-generation at 52% 3
Co-trimoxazole demonstrates 49% susceptibility nationally, though some regions report >50% effectiveness 3, 1
Beta-lactams, first- and second-generation cephalosporins show the highest resistance rates, making them unsuitable for empiric use 1
Preserved Treatment Options
Despite widespread resistance, certain agents maintain clinical utility:
Fosfomycin retains 94-100% susceptibility (inter-center range 83-97%), representing the most reliable oral option 3, 1, 2
Nitrofurantoin shows 85% susceptibility nationally (range 61-97%), though 14% resistance among UPEC isolates is concerning in some areas 3, 1
Parenteral agents maintain better activity: piperacillin-tazobactam (81%), amikacin (88%), and meropenem (88%) nationally, though regional variation exists 3
Molecular Epidemiology
The genetic landscape reveals concerning clonal spread:
The epidemic ST131 clone carrying CTX-M-15 is prevalent, particularly in phylogroup B2 (>35% of isolates), with >80% of ESBL-producing isolates belonging to this clone 2
IncF plasmids are present in >85% of isolates, with >90% having MAR index >0.2, facilitating horizontal resistance gene transfer 2
Novel TEM alleles (TEM-253 and TEM-254) have been identified, indicating ongoing evolution of resistance mechanisms 2
Clinical Implications
This high MDR prevalence necessitates specific management approaches:
Empiric fluoroquinolone and third-generation cephalosporin use should be discouraged given resistance rates of 69% and 54% respectively 3
Local antibiograms are essential for guiding therapy, as inter-center susceptibility ranges vary dramatically (e.g., nitrofurantoin 61-97%) 3
Piperacillin/tazobactam and aminoglycosides serve as carbapenem-sparing parenteral options when oral therapy fails, though monitoring for resistance is critical 3