<p><strong>BACKGROUND: </strong>Fasting hypoglycemia is a recognized occurrence among pediatric patients with acute lymphoblastic leukemia (ALL) during maintenance therapy. Existing publications describing this finding are limited to small studies and case reports. Our objective was to determine the incidence of hypoglycemia during maintenance chemotherapy and to investigate the association of age, as well as other potential risk factors, with this outcome in pediatric patients with ALL.</p>

<p><strong>PROCEDURE: </strong>This retrospective cohort study included individuals 1 to 21 years of age with ALL treated with antimetabolite-containing maintenance chemotherapy at a large children's hospital between January 2011 and December 2014. The primary endpoint was time to first documented episode of hypoglycemia during maintenance therapy, defined as single measurement of plasma glucose&nbsp;&lt;60&nbsp;mg/dL. Cox regression was used to evaluate the association with age and identify other potential risk factors.</p>

<p><strong>RESULTS: </strong>We identified 126 eligible patients, of whom 63% were documented as White, non-Hispanic, 28% as non-White, non-Hispanic, and 9% as Hispanic. Twenty-eight children (22%) had documented hypoglycemia during maintenance therapy. Younger age at the start of maintenance and hepatotoxicity documented during chemotherapy prior to maintenance initiation were associated with hypoglycemia (adjusted HR age&nbsp;=&nbsp;0.88; 95% CI, 0.78-0.99; adjusted HR prior hepatotoxicity&nbsp;=&nbsp;3.50; 95% CI, 1.47-8.36).</p>

<p><strong>CONCLUSIONS: </strong>Nearly one quarter of children in our cohort had hypoglycemia documented during maintenance chemotherapy. Younger age at maintenance initiation and hepatotoxicity during chemotherapy prior to maintenance initiation emerged as risk factors. These findings highlight the importance of counseling about the risk of, and monitoring for, hypoglycemia, particularly in young children.</p>

<p><strong>OBJECTIVES: </strong>A method to identify pediatric sepsis episodes that is not affected by changing diagnosis and claims-based coding practices does not exist. We derived and validated a surveillance algorithm to identify pediatric sepsis using routine clinical data and applied the algorithm to study longitudinal trends in sepsis epidemiology.</p>

<p><strong>DESIGN: </strong>Retrospective observational study.</p>

<p><strong>SETTING: </strong>Single academic children's hospital.</p>

<p><strong>PATIENTS: </strong>All emergency and hospital encounters from January 2011 to January 2019, excluding neonatal ICU and cardiac center.</p>

<p><strong>EXPOSURE: </strong>Sepsis episodes identified by a surveillance algorithm using clinical data to identify infection and concurrent organ dysfunction.</p>

<p><strong>INTERVENTIONS: </strong>None.</p>

<p><strong>MEASUREMENTS AND MAIN RESULTS: </strong>A surveillance algorithm was derived and validated in separate cohorts with suspected sepsis after clinician-adjudication of final sepsis diagnosis. We then applied the surveillance algorithm to determine longitudinal trends in incidence and mortality of pediatric sepsis over 8 years. Among 93,987 hospital encounters and 1,065 episodes of suspected sepsis in the derivation period, the surveillance algorithm yielded sensitivity 78% (95% CI, 72-84%), specificity 76% (95% CI, 74-79%), positive predictive value 41% (95% CI, 36-46%), and negative predictive value 94% (95% CI, 92-96%). In the validation period, the surveillance algorithm yielded sensitivity 84% (95% CI, 77-92%), specificity of 65% (95% CI, 59-70%), positive predictive value 43% (95% CI, 35-50%), and negative predictive value 93% (95% CI, 90-97%). Notably, most "false-positives" were deemed clinically relevant sepsis cases after manual review. The hospital-wide incidence of sepsis was 0.69% (95% CI, 0.67-0.71%), and the inpatient incidence was 2.8% (95% CI, 2.7-2.9%). Risk-adjusted sepsis incidence, without bias from changing diagnosis or coding practices, increased over time (adjusted incidence rate ratio per year 1.07; 95% CI, 1.06-1.08; p &lt; 0.001). Mortality was 6.7% and did not change over time (adjusted odds ratio per year 0.98; 95% CI, 0.93-1.03; p = 0.38).</p>

<p><strong>CONCLUSIONS: </strong>An algorithm using routine clinical data provided an objective, efficient, and reliable method for pediatric sepsis surveillance. An increased sepsis incidence and stable mortality, free from influence of changes in diagnosis or billing practices, were evident.</p>