TOPLINE

A prospective study found that serum levels of most uraemic toxins accumulated significantly in patients with septic shock-associated acute kidney injury (AKI) and correlated with the severity of AKI; however, their early trajectories were not independently associated with 28-day mortality or the time to liberation from organ support.

METHODOLOGY

• Researchers conducted a prospective observational study to assess changes in serum levels of seven uraemic toxins in patients with septic shock-associated AKI and their association with mortality and dependence on organ support.
• They included 114 patients with septic shock-associated AKI (median age, 66 years; 66.7% men), with AKI diagnosed within 72 hours of ICU admission for septic shock, and 15 control individuals with septic shock and without AKI.
• Serum levels of seven uraemic toxins — indoxyl sulphate, indole-3-acetic acid, para-cresyl sulphate, para-cresyl glucuronide, hippuric acid, 3-carboxy-4-methyl-5-propyl-2-furanpropionate (CMPF), and trimethylamine N-oxide — were measured daily from day 0 to day 6.
• The first objective was to evaluate the association between changes in serum levels of these uraemic toxins over the first 6 days and 28-day mortality.
• The second objective was to examine the association between toxin trajectories and the time to successful liberation from organ support — defined as weaning from vasopressors or invasive mechanical ventilation for at least 48 hours.

TAKEAWAY

• Except for CMPF, all evaluated uraemic toxins accumulated significantly more in patients with septic shock-associated AKI than in control individuals and remained significantly higher in those with severe AKI throughout the follow-up period.
• Indoxyl sulphate levels showed the strongest positive correlation with serum creatinine levels (correlation coefficient, 0.67; P < .001).
• Kidney replacement therapy was associated with lower levels of most toxins, except for indoxyl sulphate and hippuric acid.
• Overall, 44 (39%) patients died within 28 days; after adjustment for baseline severity scores, trajectories of uraemic toxins were not significantly associated with 28-day mortality or weaning from organ support.

IN PRACTICE

"Changes in serum UT [uraemic toxin] concentrations over time are significantly associated with the severity and trajectory of AKI during septic shock, but they do not appear to be independent predictors of 28-day mortality or organ support dependence," the authors wrote.

SOURCE

This study was led by Dimitri Titeca-Beauport, MD, PhD, Amiens-Picardie University Medical Centre, Amiens, France. It was published online on July 28, 2026, in Kidney360.

LIMITATIONS

The study had a single-centre design and focused on early sepsis-associated AKI. The exact timing of AKI onset could not be determined. Attrition bias may have occurred as patients discharged early contributed fewer samples over the course of the study.

DISCLOSURES

This study received financial support from a Direction Générale de l'offre de Soins grant. Some authors reported receiving honoraria; serving as employees or consultants; or holding advisory, leadership, or speakers bureau roles in various pharmaceutical companies or organisations.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.