Dear Sir: We read with great interest the study by Vandijck et al., which demonstrated promising survival rates in adult cancer patients referred to the ICU with severe sepsis and septic shock [1]. Interestingly, in their study the administration of recent chemotherapy was not associated with an increased risk of death. This is contrast to ours and previous studies in pediatric oncology patients who required admission to a PICU [2, 3]. The most common indications for intensive care treatment in pediatric oncology patients are severe sepsis, septic shock, respiratory and cardiocirculatory failure, and neurologic complications [2, 4]. In our study in children with malignancies admitted to our PICU, six risk factors were significantly associated with non-survival: non-solid tumours (leukemia/lymphoma), failure of three or more organ systems, neutropenia, septic shock, mechanical ventilation, and inotropic medication [2]. The occurrence of neutropenia in our study was related to recent administration of chemotherapy. In contrast to the study by Vandijck et al. these data point to an increased susceptibility to severe complications in children with hematologic malignancies secondary to chemotherapyrelated toxicity. So, where do the differences between adult and pediatric oncology populations come from? Notwithstanding many differences between the two cohorts (age, physiology, variations in chemotherapeutic regimens, pharmacokinetics, tumor biology etc.), the results presented by Vandijck et al. are quite surprising, and are difficult to interpret from a pediatric oncology perspective. It is our understanding that hematologic malignancies are treated with highdose frontline chemotherapies, resulting in profound bone marrow suppression, rendering the individual child highly susceptible to invasive, systemic infections (bacterial, fungal, viral, etc.). This cascade may result in severe sepsis, septic shock, and catecholamine-refractory shock which in turn are associated with multiple organ dysfunctions. It has been demonstrated in numerous studies that the number of organ dysfunctions is directly related to outcome in children with cancer [2–5]. This finding seems applicable to adult cohorts as well, and it is reflected by a significant correlation between the SOFA score and 28-day mortality in the study by Vandijck et al. [1]. One possible factor contributing to differences between pediatric and adult cancer patients may be related to the use of high doses of corticosteroids for induction therapy in children with leukemia and lymphoma. However, irrespective of the differences between children and adults, the data presented in their study should encourage us to offer intensive care treatment to these high-risk patients based upon individual clinical assessment. To initiate effective treatment strategies, early consultation with the intensivist and prompt referral to the ICU/PICU if indicated is of paramount importance.
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