Acute pyelonephritis in the emergency department: Comparing clinical and prognostic outcomes for community and long-term care

Acute pyelonephritis in older adults is associated with high morbidity, but clinical characteristics and outcomes in long-term care facility (LTCF) residents-a particularly vulnerable population-remain poorly defined. This study compared clinical features and mortality outcomes of acute pyelonephritis between LTCF residents and community-dwelling older patients (≥65 years) presenting to the emergency department.

We conducted a retrospective analysis of patients aged ≥65 years diagnosed with acute pyelonephritis between January 2018 and December 2023. Patients were classified as LTCF-acquired or community-acquired acute pyelonephritis. Clinical presentations, laboratory values, and in-hospital mortality were compared. Logistic regression analyses identified independent predictors of in-hospital mortality.

Among 831 participants, 187 (22.5%) were LTCF residents. Compared with community-dwelling patients (median age, 78.0 years), the LTCF group was significantly older (median age, 83.0 years). They also showed significantly higher rates of cerebrovascular disease (53.5% vs. 27.9%) and long-term catheter use (37.4% vs. 6.1%), and more frequently presented with altered mental status (42.8% vs. 19.3%), but exhibited fewer urinary tract symptoms (28.3% vs. 73.0%). Overall in-hospital mortality was 4.0% (n = 33). Multivariable analysis identified LTCF residence (OR, 3.73; 95% CI, 1.54-9.04; p = 0.004) and lactate-to-albumin ratio (OR, 2.48; 95% CI, 1.46-4.21; p = 0.001) as independent predictors of mortality.

LTCF residents with acute pyelonephritis exhibit atypical clinical presentations, with more frequent altered mental status and fewer urinary symptoms than community-dwelling patients. Both LTCF residency and elevated lactate-to-albumin ratio independently predict mortality, supporting the need for heightened clinical vigilance and tailored management in this vulnerable population.