AKI in Severe Legionnaires' Disease in Intensive Care Unit

Legionnaires' disease (LD) can cause severe pneumonia, requiring intensive care and frequently associated with multiorgan failure. The mechanisms and prognosis of kidney complications in LD remain poorly characterized. We aimed to describe the incidence, clinical characteristics, and prognosis of acute kidney injury (AKI) in patients who are critically ill with LD and identify factors associated with AKI in a multicenter cohort.

This multicenter retrospective cohort study was conducted in 39 intensive care units (ICUs) in France between 2012 and 2024. Inclusion criteria were a diagnosis of LD requiring invasive mechanical ventilation.

A total of 561 patients were included. Patients exhibited high severity, with a mean sequential organ failure assessment score on D1 of 7.9; 69% had severe acute respiratory distress syndrome (ARDS) and 81% with septic shock. The incidence of AKI was 74% in ICU, with 44% requiring renal replacement therapy (RRT). Rhabdomyolysis (16%), hematuria (52%), and proteinuria (mean 1.49 g/l) were commonly observed. Rhabdomyolysis was an independent risk factor for AKI and RRT requiremen-adjusted odds ratio [aOR], 3.99 [1.59-10.00]; P = 0.003 and aOR, 4.07 [2.17-7.63]; P < 0.001, respectively. RRT requirement was associated with significantly increased mortality-aOR, 2.49 [1.27-4.87]; P = 0.008 at D28, pLog-rank < 0.001. In an exploratory analysis, dual anti-Legionella antibiotic therapy, administered in 87% of cases, was independently associated with lower day-28 mortality (aOR, 0.27; [95% CI, 0.13-0.58]; P = 0.001).

AKI appears to be highly prevalent in patients with severe LD, with a high frequency of rhabdomyolysis and proteinuria, suggesting marked kidney involvement. Rhabdomyolysis was independently associated with AKI onset and RRT requirement. AKI was associated with significantly increased mortality, whereas dual anti-Legionella therapy was protective.