1142. A multicenter cohort study to identify differences between methicillin-susceptible and methicillin-resistant Staphylococcus aureus infections in pediatrics in Bogotá, Colombia, 2014-2018
Authors: Camacho Jhon , Tobar Ivan Felipe Gutiérrez , Brand Katherine , Sosa Yeni , Vásquez Pablo , Gómez Leidy , Romero Laura , Rojas Diana , Ortiz Cesar , Camacho German , Wilches María , Hernandez Juan , Velandia Jessica , Mancera Luz , Palacios María , Beltran Sandra 
Published: December 2021

Abstract

Background
The epidemiology of methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) S. aureus in pediatrics has changed in recent years. MRSA infections have been reported to be more severe than MSSA.

Methods
Multicenter retrospective cohort, in 6 pediatric hospitals in Bogotá, Colombia, between January 1, 2014, and December 31, 2018, 1 isolate was included for patient from the same origin. Infections were classified into: SSTI, osteoarticular, bacteremia, or pneumonia.The objective is to establish differences between clinical, laboratory, and outcomes of MSSA and MRSA infections, according to origin of the infection in a pediatric population from Bogotá, Colombia.

Results
551 patients were included; 211 (38%) MRSA and 340 (62%) MSSA, in total 703 cultures. Figure 1. Some risk factors were statistically associated with MSSA: Heart disease (3.3% Vs. 0.5%) neurologic disease (5.9% vs. 2.4%),
surgery in last 6 months (11% vs. 5%), use of vascular or external devices (3% vs 11%) and previous hospitalization &gt;3 days (11% vs 17%) Table 2. In 84/159 (52%) cases, bacteremia was associated with osteoarticular infection (OI), 19/159 (13%) with pneumonia, 21/159 (13%) with SSTI, 14/159 (9%) with other foci, 21/159 (13%) were primary. Independently of the origin, PICU admittance was more frequent in MRSA (52% vs. 28), as well as mechanical ventilation (MV) (30% vs. 13%) and inotropic support (IS )(38% vs 17%). Of 136 osteoarticular infections, 59 (43,4%) were MRSA and 77 (56,6%) MSSA. MRSA isolates required more than 3 surgical procedures (45% vs 24%), more PICU admittance (36% vs. 12%) and IS (27% vs. 5%). Complicated pneumonia was more frequently associated to MRSA in comparison with MSSA (57% vs. 23%). In pneumonia, MRSA also was significantly associated with PICU. (74%vs 50%), MS (61%vs 32%), and VS (52% vs 27%). SSTI was not associated with greater severity or worse outcome (PICU, MV, IS) according to S. aureus susceptibility.

Table 3b. Infection groups depending on the presence or not of resistance

Conclusion
MRSA was associated with more severe course in bacteremia, OI and pneumonia. It is interesting that some classically risk factors associated with MRSA infections were found to be related to MSSA. In general, with SSTI exception, MRSA increase risk of PICU, mechanical support and inotropic support in a pediatric population in Bogotá, Colombia.

Disclosures
Ivan Felipe Gutiérrez Tobar, n/a, Pfizer and MSD (Advisor or Review Panel member, Research Grant or Support, Speaker’s Bureau, Has received support from Pfizer and MSD for participation in congresses and has received conference payments from Pfizer)Pfizer and MSD (Speaker’s Bureau, Other Financial or Material Support, Has received support from Pfizer for participation in congresses) Sandra Beltran, n/a, Pfizer (Other Financial or Material Support, Has received support from Pfizer for participation in congresses)