Direct Antibiogram Susceptibility Testing vs Isolation Followed by Subculture in Gram Negative Urine Tract Infections

Background: Urine tract infections (UTIs) are the main drivers of antimicrobial resistance, especially in gram-negative bacteria. In low-income countries where automized antibiogram determination is not available, there is a need to speed up the identification of resistance profiles of bacteria, which would serve to decrease the days of exposure to broad-spectrum empiric antibiotics. Methods: We conducted a study to evaluate the feasibility and efficacy of direct identification and antimicrobial susceptibility testing on 50 gram-negative bacterial UTI specimens. We then compared these findings to the standard manual method traditionally used in low-resource settings. Results: The findings of our study suggest that direct antimicrobial susceptibility testing on urine samples with isolated gram-negative bacilli on gram stain is a reliable tool for rapid susceptibility determination in the vast majority of UTIs. It allowed for determination of an accurate antibiogram within 24 hours of sample collection, which is 24 to 48 hours faster than the standard method. Conclusion: This approach offers an alternative method of UTI sample handling that can significantly reduce the time to targeted therapy, thereby promoting antimicrobial stewardship and mitigating the growing threat of antibiotic resistance.