Inappropriate Empirical Therapy in Urinary Tract Infections and Potential Consequences 

Speaker: Emmanouela Maltezaki, Greece

Background:

• Urinary tract infections (UTIs) are among the most common serious bacterial infections in children.
• Empirical treatment is often initiated before culture results, based on local resistance patterns.
• Inappropriate empirical therapy (IET) can lead to complications such as treatment failure, sepsis, prolonged hospital stay, and antimicrobial resistance.

Study Aim:

To evaluate the consequences of inappropriate empirical antibiotic treatment in pediatric UTI cases, including its impact on clinical outcomes.

Study Design:

1. Retrospective cohort study (2007–2023) at a single centre in Greece.
2. Included: 778 children aged 30 days to 15.9 years hospitalized with UTIs.
3. Two groups:
   1. Group 1: Received appropriate empirical therapy (based on antibiogram).
   2. Group 2: Received inappropriate empirical therapy.
4. Excluded: Incomplete records and unclear prior antibiotic exposure.
5. Variables Compared Between Groups: Using Fisher’s exact test and Mann–Whitney test, the following parameters were compared:
   1. Duration of hospitalization
   2. Bacteraemia rate
   3. Positive repeat culture
   4. Renal scarring on DMSA scan
   5. Recurrent infections
   6. Prior antibiotic exposure
   7. Type of uropathogens (E. coli vs. non-E. coli)
   8. Abnormal imaging findings

Pathogen Distribution and Resistance Patterns:

• ESBL production was the main reason for inappropriate therapy.
• Third-generation cephalosporins were used throughout the study, but showed reduced efficacy in resistant cases.

Clinical Outcomes:

UTIs treated with IET were linked to:

• Higher rates of bacteraemia
• Longer hospital stays
• Recurrent infections
• Renal scarring on DMSA scans

Outcome Statistics:

• 50% of cases had renal scarring
• 10% had prolonged hospitalization
• 6% had new UTI episodes within a month
• 4 patients had persistent positive cultures post-antibiotic
• 6 cases developed bacteraemia

Key Recommendations:

1. Change antibiotics based on antibiogram results, even if the child is clinically improving.
2. Reduce inappropriate therapy by:
3. Faster pathogen identification
4. Early risk stratification for resistant pathogens

Limitations:

• Single-centre data from a high-resistance region.
• Few similar pediatric studies exist, emphasizing the value of this research.

Conclusion:

While most children with inappropriate empirical therapy recovered without serious complications, these cases had higher risks of adverse outcomes such as recurrent infection, renal damage, and longer hospitalization. Strict adherence to antibiogram results is essential to minimize long-term risks.

ESPID 2025, 26-30 May, Bucharest