Multidrug resistant and extensively drug resistant Acinetobacter baumannii hospital infection associated with high mortality: a retrospective study in the pediatric intensive care unit

Background: Multidrug resistant (MDR) and extensively drug resistant (XDR)Acinetobacter baumanniipresents challenges for clinical treatment and causes high mortality in children. We aimed to assess the risk factors and overall mortality for MDR/XDRAcinetobacter baumanniiinfected pediatric patients. Methods: This retrospective study included 102 pediatric patients who developed MDR/XDRAcinetobacter baumanniiinfection in the pediatric intensive care unit (PICU) of Shanghai Children's Hospital in China from December 2014 to May 2018. Acinetobacter baumanniiclinical isolates were recovered from different specimens including blood, sputum, bronchoalveolar lavage fluid, cerebrospinal fluid, ascites, hydrothorax, and urine. Antibiotic susceptibility test was determined according to the Clinical and Laboratory Standards Institute interpretive criteria. Clinical and biological data were obtained from the patients' medical records. Results: 102 patients withAcinetobacter baumanniiinfection were enrolled. The median age was 36 (9.6, 98.8) months, and there were 63 male in the case group. The overall mortality rate was 29.4%, while theAcinetobacter baumannii-associated mortality rate was 16.7% (17/102, 12 bloodstream infections, 4 meningitis and 1 intra-abdominal infection). Bloodstream infections occurred in 28 patients (27.5%), and 10 patients (9.8%) among them had central line-associated bloodstream infections (6 central venous catheters, 2 PICCs, 1 venous infusion port and 1 arterial catheter). Cerebrospinal fluid (CSF) cultures were positive in 4(3.9%) patients. 14(13.7%) patients got positive cultures in ascites and hydrothorax. Lower respiratory isolates (56/102) accounted for 54.9% of all patients. Non-survival patients appeared to have a lower NK cell activity (6.2% +/- 3.61% vs. 9.15% +/- 6.21%,P = 0.029), higher CD4+ T cell ratio (39.67% +/- 12.18% vs. 32.66% +/- 11.44%,P = 0.039),and a higher serum level of interlukin-8 (IL-8, 15.25 (1.62, 47.22)pg/mL vs. 0.1 (0.1, 22.99)pg/mL,P = 0.01) whenAcinetobacter baumanniiinfection developed. Multivariate logistic analysis indicated that high serum level of Cr (RR, 0.934, 95%CI, 0.890-0.981;P = 0.007) and high BUN/ALB level (RR, 107.893, 95%CI, 1.425-870.574;p = 0.005) were associated with high risk of mortality in MDR/XDRAcinetobacter baumanniiinfected patients. Conclusion: MDR/XDRAcinetobacter baumanniiinfection is a serious concern in pediatric patients with high mortality. Bloodstream and central nervous system infection accounted for high risk of death. Acute kidney injury is associated with high risk of mortality.