Acute Kidney Injury and Hemolytic Uremic Syndrome in Severe Pneumococcal Pneumonia – A Retrospective Analysis in Pediatric Intensive Care Unit

Objectives: This study aimed to evaluate the prevalence of acute kidney injury (AKI) and hemolytic uremic syndrome (HUS) in severe pediatric pneumonia due to Streptococcus pneumoniae and to identify factors associated with AKI and HUS in these patients. Methods: We retrospectively analyzed pediatric patients who were admitted to our pediatric intensive care unit due to severe pneumococcal pneumonia between 2013 and 2019. Results: Forty-two patients with a median age of 4.3 years were included. Among these patients, 14 (33.3%) developed AKI, including seven (16.7%) stage 1, two (4.8%) stage 2, and five (11.9%) stage 3 AKI. Features of HUS were present in all of the patients with stage 3 AKI, and four required renal replacement therapy, with median duration of 10.5 days (range 3-16 days). All patients with HUS required mechanical ventilation and inotropic support. Patients with lower leukocyte and platelet counts, serum sodium and bicarbonate levels, positive urine dipstick (heme or protein ≥ 2+) and presence of bacteremia were associated with stage 2-3 AKI. Conclusions: Pediatricians should be aware of relatively high prevalence of kidney involvement in severe pneumococcal pneumonia, with one-third having AKI, and 11.9% developing HUS. Majority (80%) of HUS patients required renal replacement therapy. Positive urine dipstick, serum sodium and bicarbonate at presentation, which can be measured in point-of-care tests, may potentially be useful as quick tests to stratify the risks of moderate to severe AKI.