Assessment of the impact of Hydration on the Incidence of Acute Kidney Injury (AKI) with Intravenous Acyclovir: A retrospective observation study

Background Intravenous (IV) acyclovir use is associated with adverse events, including acute kidney injury (AKI). Hydration to increase the urine flow to prevent crystal precipitation is a strategy to prevent acyclovir-induced nephrotoxicity. To our knowledge, no study has compared the incidence of AKI among patients receiving IV acyclovir with proper hydration. We aimed to compare the incidence of AKI in patients who received IV acyclovir with or without hydration. Methods This was a retrospective, observational study at King Abdulaziz Medical City, Jeddah. Adult patients who received IV acyclovir from 2019–2022 were included. We compared the incidence of AKI between hydrated and nonhydrated patients and between patients who received adequate hydration and those who received inadequate hydration. Adequate hydration is defined as at least 1500 mL of IV fluid daily during the whole course of acyclovir. For descriptive univariate analysis, Fisher’s exact test and a t test were used. For potential differences in AKI status, we used multiple binary logistic and multiple logistic regression models through SAS 9.4. The two-sided statistical significance level was set at P < 0.05. Results A list of 281 patients was generated. Two hundred and one patients were eligible, 33 of whom had repeated courses. Two hundred sixty-six treatment courses were included in the final analysis. The baseline characteristics were similar between the two groups. The estimated incidence of AKI was 11.6% in the hydrated group vs. 18.8% in the nonhydrated group, with no statistically significant difference between the two groups (P = 0.39). According to the multiple logistic regression model, there was no statistically significant difference in the odds of AKI between patients who received adequate hydration and those who received inadequate hydration (OR = 0.81, 95% CI (0.31–2.17)). There was a statistically significant increase in the odds of anuria (OR = 3.64, 95% CI (1.02–13.01)) and the serum creatinine level (OR = 1.06, 95% CI (1.001, 1.12)). Conclusions Fewer AKIs trend among hydrated patients than among nonhydrated patients was detected. Additionally, inadequate hydration with IV acyclovir resulted in an increase in serum creatinine and anuria. Maintaining continuous daily hydration could be the key to preventing acyclovir-induced nephrotoxicity.