Symptomatic Urinary Tract Infections in Pregnancy: Microbiological Analysis and Susceptibility Profile in Community Infections Seen in the Emergency Department of a Tertiary Hospital in São Paulo

Urinary tract infections (UTIs) are the most prevalent bacterial infections in pregnancy and represent an important cause of maternal and perinatal morbidity. Proper clinical management requires up-to-date knowledge of local epidemiology and antimicrobial susceptibility patterns, especially in initial care settings. This study aimed to describe the agents isolated from urine cultures of pregnant women with community-acquired UTI and to analyze the associated antimicrobial resistance profile. Retrospective observational study of pregnant women seen in the emergency department of a tertiary hospital in São Paulo between February and June 2025, with urinary symptoms and positive urine culture. Fifty-nine patients were included; eight were excluded due to growth of contaminants (coagulase-negative staphylococci), resulting in 51 samples analyzed. Variables assessed included age group, distribution of isolated pathogens, extended-spectrum β-lactamase (ESBL) production and antimicrobial susceptibility profile. Most pregnant women were between 21 and 30 years of age (59.3%), followed by 31 to 40 years (27.1%). Escherichia coli was the most prevalent pathogen (66.7%), followed by Staphylococcus saprophyticus (9.8%), Klebsiella pneumoniae (7.8%), Streptococcus agalactiae (5.9%), Proteus mirabilis, Klebsiella aerogenes, Staphylococcus aureus and Morganella morganii (each 3.9% or less). Among the 43 enterobacteria isolated, 12 were resistant to quinolones (27.9%) and 2 were ESBL producers (4.7%). All S. agalactiae isolates were susceptible to ampicillin and amoxicillin-clavulanate. S. saprophyticus showed intermediate profile for quinolones, with preserved susceptibility to nitrofurantoin and sulfamethoxazole-trimethoprim. The epidemiological profile of symptomatic community UTIs in pregnant women demonstrated a predominance of enteric Gram-negative bacilli and an overall susceptibility pattern favorable to antimicrobial options considered safe in pregnancy. The high rate of quinolone resistance, even in community infections, reinforces the importance of continuous microbiological surveillance to guide empirical regimens and ensure maternal-fetal safety.