<p><strong>BACKGROUND: </strong>Pneumonia is the leading cause of death in children under age of 5 years worldwide. The role of vitamin D in respiratory infections including pneumonia is unclear; therefore, we aimed to determine if children with lower respiratory tract infections had low serum 25-hydroxyvitamin D3 .</p>

<p><strong>METHODS: </strong>We performed a case-control study of children ages 3-60 months from the Guatemala City metropolitan area, hospitalized with community-acquired pneumonia between September and December 2012. Controls were selected from the well-baby/care immunization clinics serving the population from which cases emerged. We analyzed serum 25-hydroxyvitamin D3 levels and conducted parental interviews to assess subject age, sex, race, feeding type, vitamin D supplementation, frequency of sun exposure, and maternal education. Height and weight were ascertained from medical records. Complete information was available for 70 (83%) of 84 eligible cases and 68 (60%) of 113 eligible controls.</p>

<p><strong>RESULTS: </strong>The median (IQR) serum 25-hydroxyvitamin D3 concentration for cases was 23.2 ng/ml (14.4-29.9) compared to 27.5 ng/ml (21.4-32.3) in controls (P = 0.006). Multiple regression analysis using an a priori cut-point for vitamin D of &lt;20 ng/ml showed that children with lower respiratory tract infections were more likely to have low 25-hydroxyvitamin D3 levels than controls (adjusted odds ratio 2.4, 95% confidence interval 1.1-5.2, P = 0.02).</p>

<p><strong>CONCLUSIONS: </strong>Children with lower respiratory tract infections in Guatemala had low 25-hydroxyvitamin D3 levels. Pediatr Pulmonol. © 2016 Wiley Periodicals, Inc.</p>

<p><strong>OBJECTIVES: </strong>To describe the prevalence of and identify risk factors for acute occlusive arterial injury (AOAI) in a large volume pediatric cardiac catheterization laboratory.</p>

<p><strong>BACKGROUND: </strong>AOAI is a known complication after pediatric cardiac catheterization. Prevalence and risk factors in the modern era are incompletely described.</p>

<p><strong>METHODS: </strong>A retrospective cohort study including all cardiac catheterization procedures performed between January 1, 2005 and June 30, 2010 was performed. Case status was defined by ≥1 of the following: exam consistent with occlusive arterial injury, use of an anticoagulant within 48 hr of catheterization to restore or maintain patency of the artery, or documented occlusive arterial injury by radiologic study.</p>

<p><strong>RESULTS: </strong>3,254 patients had 5,715 catheterization procedures, which included 3,859 arterial access events. 167 cases of AOAI were identified for an overall prevalence of 4.3% among arterial access events. Multiple logistic regression identified independent risk factors: weight category [&lt;4 kg: odds ratio (OR) 4.5 (95% CI: 2.6-7.7), P &lt; 0.001; 4-6 kg: OR 2.1 (1.3-3.5), P = 0.002, compared to 6-8 kg referent group]; largest catheter outer diameter French size [OR 1.6 (1.3-1.9), P &lt; 0.001]; final activated clotting time (ACT) &lt;250 sec [OR 1.9 (1.4-2.7), P &lt; 0.001]; and need for arterial catheter exchange [OR 1.8 (1.02-3.2), P = 0.04].</p>

<p><strong>CONCLUSIONS: </strong>AOAI occurred in 4.3% of pediatric cardiac catheterizations, and was most likely in smaller children and those with larger arterial catheters. Risk was also independently increased by arterial catheter exchange and having a final ACT &lt;250 sec. These data act as an important benchmark and identify areas for intervention for future studies.</p>