A multicenter study on the epidemiology of complicated parapneumonic effusion in the era of currently available pneumococcal conjugate vaccines.

BACKGROUND: Parapneumonic effusion (PPE) is a common complication of pneumonia. Streptococcus pneumoniae is the most common cause of bacterial pneumonia. A reduction in pneumonia hospitalizations has been observed since the introduction of the 7-valent pneumococcal conjugate vaccine (PCV7). Despite this apparent benefit, an increase in the incidence of PPE was recorded in some countries following PCV7 implementation. As the 13-valent pneumococcal conjugate vaccine (PCV13) was expected to provide a wider protection against PPE, the aim of the present study was to evaluate the impact of PCV13 introduction on the epidemiology of complicated parapneumonic effusion (c-PPE) among children in the Athens greater area. METHODS: All cases of community-acquired pneumonia (CAP) with PPE requiring chest tube insertion (complicated PPE, c-PPE) hospitalized in the 3 public Children's hospitals in Athens between 01/01/2004 and 31/12/2019 were included in the study. RESULTS: A total of 426 cases of c-PPE associated with pneumonia were recorded of which 198 were admitted during 2004-2010 (period A, prePCV13/PCV -7 introduction period) and 228 during 2011-2018 (period B, post - PCV13 period). A definite bacterial etiology was established in 44.4 % of all cases and of those 25.4 % were caused by S. pneumoniae. An increasing trend in c-PPE incidence was observed during period A; although, a significant decrease on c-PPE annual rates was observed during the period B (p = 0.011), a remarkable increase in serotype 3 cases was recorded. CONCLUSION: A decreasing time trend in c-PPE cases among children was shown after the introduction of PCV13 in our area. However, serotype 3 is nowadays a common cause of PPE. Hence, continuous surveillance is imperative in order to follow c-PPE epidemiology over time.

Predictive Factors for Gram-negative Versus Gram-positive Bloodstream Infections in Children With Cancer.

BACKGROUND: Identifying potential predictive factors for the type of bacteremia (Gram-negative vs. Gram-positive) in children with cancer would be crucial for the timely selection of the appropriate empiric antibiotic treatment. MATERIALS AND METHODS: Demographic, clinical, and laboratory characteristics of children with cancer and a bacterial bloodstream infection (BSI) (February 1, 2011 to February 28, 2018) in a tertiary pediatric oncology department were retrospectively examined and were correlated with the type of isolated bacteria. RESULTS: Among 224 monomicrobial bacterial BSI episodes, Gram-negative and Gram-positive bacteria were isolated in 110 and 114 episodes, respectively. Gram-negative bacteria were isolated significantly more frequently in girls (Gram-negative/Gram-positive ratio 1.7:1) versus boys (Gram-negative/Gram-positive ratio 0.72:1), P=0.002, in patients with previous BSI episodes (1.4:1) versus those without (0.8:1), P=0.042, and in children with hematologic malignancy (1.3:1) versus those who suffered from solid tumors (0.52:1), P=0.003. Gram-negative BSI episodes were more frequently correlated with a lower count of leukocytes, P=0.009, neutrophils, P=0.009 and platelets, P=0.002, but with significantly higher C-reactive protein (CRP) levels, P=0.049. Female sex, hematologic malignancy, and higher CRP levels remained independent risk factors for Gram-negative BSI in the multivariate analysis. Among neutropenic patients, boys with solid tumors and a recent central venous catheter placement appear to be at increased risk for Gram-positive BSI in the multivariate analysis. CONCLUSIONS: Although Gram-negative and Gram-positive BSIs are close to balance in children with cancer, Gram-negative bacteria are more likely to be isolated in girls, children with hematologic malignancies and those with higher CRP level at admission. In contrast, neutropenic boys with solid tumors and a recently placed central venous catheter may be at increased risk for Gram-positive BSI indicating probably the need for initially adding antibiotics targeting Gram-positive bacteria.