Impact of inborn errors of metabolism on admission and mortality in a pediatric intensive care unit

The authors conducted a retrospective analysis of the patients admitted to a pediatric intensive care unit (PICU) during a five-year period, with specific focus on those with a suspected or confirmed diagnosis of inborn errors of metabolism (IEM), in order to ascertain the resources required to care for these patients. Medical records were reviewed for all admissions between January 1998 and December 2002 in a single metabolic referral center, and a subset of patients were identified with suspected IEM at admission or diagnosed IEM at hospital discharge. These patient charts were then further reviewed and the following information was extracted: IEM diagnosis, demographic data, biochemical characteristics at admission, need for mechanical ventilation, use of extracorporeal removal therapy, and outcome at PICU discharge. The study population comprised 70 patients (2.2% of all admissions during the study period) and included 33 neonates and 37 children aged >28 days. IEM diagnosis was known at the time of admission to the PICU in 9/33 of the neonates and 23/37 of the older children. Forty-three of the patients required invasive mechanical ventilation, while continuous extracorporeal removal therapy was used in 27 children. The median length of PICU stay was 3 days (range, 1 to 13 days) and 20 patients (28.6%) died. In conclusion, these observations show that inherited metabolic disease may be as frequent a primary diagnosis as septic shock in some PICUs. In neonates, these diseases are not usually diagnosed prior to PICU admission. Patients with IEM admitted to a PICU require aggressive support (including mechanical ventilation and extracorporeal removal therapies), and consume significant resources for relatively short PICU stays. These patients constitute a significant diagnostic and therapeutic challenge for pediatric intensivists.