The authors reply.

Pediatric Critical Care Medicine www.pccmjournal. org 391 The authors reply: We thank the authors for their interest in our study and for their appreciation of the effort to better describe the current prevalence of sepsis in American PICUs. Souza et al (1) rightly point out that a paucity of data exists regarding the epidemiologic characteristics of global pediatric severe sepsis and note the variability of prevalence in these three recently published studies (2–4). In the United States, we are fortunate to have access to large pediatric administrative and clinical databases that allow analysis of multiple centers. However, Souza et al (1) appropriately characterize the dilemma of depending on subjective International Classification of Diseases, 9th Edition (ICD-9) codingbased data for sepsis definition. Wang et al (4) prospectively collected data using the more clinically driven 2005 International Pediatric Sepsis Consensus Conference criteria. Meanwhile, the two American studies used ICD-9 and coding data for retrospective analysis of the Pediatric Health Information Systems (PHIS) database. We need to point out that differences in pediatric population chosen for study can account for variability in reported prevalence. In our study (2), we chose to focus on incidence of sepsis (whether using ICD-9 sepsis codes or infection plus organ dysfunction criteria) specifically in pediatric ICU patients, excluding neonates. In contrast, Balamuth et al (3). evaluated sepsis in both neonates and children, likely including both PICU and neonatal ICU patients from the PHIS database. Regardless of differences in design of these studies, we agree that increased attempts to use global sepsis criteria would allow an “apples to apples” comparison within institutions and also across international boundaries. A recent editorial by Kissoon (6) similarly highlighted the need of a consistent global definition. Coupling of administrative databases such as PHIS with clinical databases such as VPS offers one opportunity for enhanced consistency, but likely does not allow for international comparison. A simple bedside checklist consisting of objective clinical variables would be an alternative tool that could be easy to use internationally and in both resource-rich and resource-poor settings. For any such effort, however, ongoing United States by Balamuth et al (3) and Ruth et al (1) showed prevalence of sepsis ranging from 0.7% to 7.7%, with mortality rates varying from 8.2% to 14.4%. Interestingly, significant differences in prevalence and mortality were also observed by the authors with the use of two sepsis coding strategies. Although the International Classification of Diseases combination code (infection plus organ dysfunction) resulted in higher prevalence and lower mortality rates, the use of the Clinical Modification code for sepsis and septic shock showed lower prevalence and higher mortality rates for pediatric sepsis, with only a minority of patients being diagnosed by both methods. In the study conducted by Wang et al (2) in China, the reported prevalence and mortality rates of pediatric sepsis were 5.5% and 3.5%, respectively. The Latin American Pediatric Sepsis Study study, conducted by our group, whose results are still unpublished, used the same diagnostic criteria applied by Wang et al and observed a 42.6% prevalence and a 14.2% mortality rate for sepsis in children from 21 PICUs in five countries of Latin America. As many authors have pointed out, several factors, such as the definition criteria, population, study design, geographic region, and timing of data collection, may influence the observed prevalence of sepsis, which may result in up to 3.5-fold difference in rates according to the methods used (7). The high variability in the data presented in these studies, including ours, suggests that the lack of a unique definition is an important obstacle for a more comprehensive understanding of the differences in epidemiology and outcome patterns of pediatric sepsis in different regions and populations over the world. Global initiatives have proven effective in reducing the morbidity and mortality of severe adult diseases, such as sepsis, stroke, and ischemic heart diseases. We believe that it is time to do the same with pediatric sepsis. Nevertheless, global attention of pediatric sepsis can only be achieved with the standardization of definitions and diagnostic criteria, in order to incorporate the regional aspects and necessities among different populations. The search for diagnostic criteria that can be easily applied at the bedside, regardless of the differences in medical practices or economic development, may represent the first step to reduce the unquestionable burden of pediatric sepsis worldwide. This study was performed at the Hospital Universitário da Universidade de São Paulo, Sao Paulo, SP, Brazil. The authors have disclosed that they do not have any potential conflicts of interest.