Prevalence and risk factors for trimethoprim-sulfamethoxazole-resistant Escherichia coli among women with acute uncomplicated urinary tract infection in a developing country.
BACKGROUND
Prospective studies from developing countries that have investigated risk factors for trimethoprim-sulfamethoxazole (TMP-SMX)-resistant Escherichia coli in women with uncomplicated urinary tract infection (UTI) remain scarce.


METHODS
Women with acute uncomplicated UTI were enrolled prospectively. Urine was sent for antimicrobial susceptibility testing. Logistic regression analysis was used to identify risk factors for TMP-SMX resistance.


RESULTS
Of 405 participants, 229 (56.5%) had bacteriuria (mean age 31.9 ± 9.5 years). In the previous 12 months, 77 (33.6%) had experienced at least one UTI episode and 106 (46.3%) reported antimicrobial use. The most common uropathogens were E. coli (75.8%) and Staphylococcus saprophyticus (8.9%). For the 179 E. coli, resistance rates were highest for ampicillin (64.3%) and TMP-SMX (41.3%). Resistance to cephalosporins, nitrofurantoin, and fluoroquinolones was much lower compared with the hospital laboratory-based surveillance data. Risk factors for TMP-SMX resistance were UTI in the last 6 months (odds ratio 2.22; p = 0.04) and the number of UTI episodes in the past year (odds ratio 2.06; p = 0.004). The number of UTI episodes (adjusted odds ratio 2.21; p = 0.02) remained significant on multivariate analysis.


CONCLUSIONS
TMP-SMX resistance was high. Number of previous UTI episodes was associated with increased risk of resistance; prior antimicrobial use was not. Hospital antibiograms should be used with caution when treating uncomplicated UTI.
Department of Medicine, The Medical City, Pasig, Metro Manila, Philippines; Infectious Disease Practice and Innovations, The Medical City, Ortigas Ave., Pasig, Metro Manila, Philippines. Electronic address: louiemarMD@gmail.com.
Louie Mar
LM
Gangcuangco
Department of Medicine, The Medical City, Pasig, Metro Manila, Philippines; Infectious Disease Practice and Innovations, The Medical City, Ortigas Ave., Pasig, Metro Manila, Philippines; Section of Infectious Diseases, Department of Medicine, University of the Philippines College of Medicine, Pedro Gil, Manila, Philippines.
Marissa
M
Alejandria
Department of Medicine, The Medical City, Pasig, Metro Manila, Philippines; Section of Infectious Diseases, Department of Medicine, University of the Philippines College of Medicine, Pedro Gil, Manila, Philippines.
Karl Evans
KE
Henson
Department of Medicine, The Medical City, Pasig, Metro Manila, Philippines.
Liezel
L
Alfaraz
Department of Medicine, The Medical City, Pasig, Metro Manila, Philippines.
Rona Marie
RM
Ata
Department of Medicine, The Medical City, Pasig, Metro Manila, Philippines.
Maritess
M
Lopez
Department of Medicine, The Medical City, Pasig, Metro Manila, Philippines; Infectious Disease Practice and Innovations, The Medical City, Ortigas Ave., Pasig, Metro Manila, Philippines; Section of Infectious Diseases, Department of Medicine, University of the Philippines College of Medicine, Pedro Gil, Manila, Philippines.
Mediadora
M
Saniel
D000208:Acute Disease; D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use; D003906:Developing Countries; D024881:Drug Resistance, Bacterial; D004927:Escherichia coli Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D005260:Female; D024841:Fluoroquinolones / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D008826:Microbial Sensitivity Tests; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000453:epidemiology; D057790:Staphylococcus saprophyticus / Q000187:drug effects; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000494:pharmacology* / Q000627:therapeutic use; D014552:Urinary Tract Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D056689:Uropathogenic Escherichia coli / Q000187:drug effects*; D055815:Young Adult
D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D015662:Trimethoprim, Sulfamethoxazole Drug Combination
Acute uncomplicated UTI; Escherichia coli; Philippines; TMP–SMX resistance