Background and Importance Vancomycin is used in the treatment of resistant gram-positive microorganism infections. Due to a narrow therapeutic range, its use is limited by its nephrotoxicity, which ranges from 5–43% according to the literature. Therefore, it’s important to identify patients who may benefit from pharmacokinetic monitoring. The duration of treatment and a high minimum concentration of vancomycin are factors associated with nephrotoxicity.

Aim and Objectives To determine the incidence of nephrotoxicity associated with the use of vancomycin in monitored patients and identify factors related to its occurrence.

Material and Methods Retrospective, observational study in patients who underwent pharmacokinetic monitoring between 2022 and January 2023, in a third-level hospital. Demographic data and information related to antibiotic treatment were collected, including duration and indication, initial dose and frequency of administration, minimum steady-state concentration of vancomycin, and renal function data: baseline creatinine, creatinine at the start of antibiotic treatment, and at two days to assess the development of Acute Kidney Injury (AKI), defined by the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines as an increase in creatinine by 0.3mg/dL compared to the initial value after two consecutive days of treatment.

These data were analysed with Jamovi software.

Results 93 patients, 71% men, mean age 62 (18–92).

8.6% of the patients met the criteria for AKI secondary to vancomycin.

Factors associated with nephrotoxicity age equal to or greater than 65 years (p=0,04), being female (p=<0,001) and having a BMI equal to or greater than 30kg/m2 (p=0,03).

There was no observed higher incidence of nephrotoxicity based on the use of high doses or the location of the infection.

Conclusion and Relevance In our study, we observed an advanced age, being female, a BMI over 30kg/m2 and a high minimum concentration of vancomycin as factors associated with nephrotoxicity. Given the incidence of AKI secondary to vancomycin treatment, it’s important to recognise the factors associated with its occurrence in order to identify patients who may benefit from pharmacokinetic monitoring, thus optimising treatment and limiting nephrotoxicity.

References and/or Acknowledgements 1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9549902/pdf/ijgm-15-7685.pdf

2. https://bpspubs.onlinelibrary.wiley.com/doi/epdf/10.1111/bcp.15429

3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10296058/pdf/ofad264.pdf

4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10296058/pdf/ofad264.pdf

5. https://www.ilaphar.org/incidencia-de-nefrotoxicidad-en-pacientes-monitorizados-en-tratamiento-con-vancomicina/

6. https://rdu.unc.edu.ar/bitstream/handle/11086/18090/13904%20tesis%202020%20Suarez%20Alejandra%20TIF%20Farma%20Hospitalaria.pdf?sequence=1

7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8520844/

8. https://bpspubs.onlinelibrary.wiley.com/doi/epdf/10.1111/bcp.14834

9. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9691676/pdf/fphar-13-1041152.pdf

Conflict of Interest No conflict of interest.