567 - Molecular Diagnostic Testing Variation and Outcomes in Pediatric Complicated Community-Acquired Pneumonia

Publication Number: 2552.567

Marina Dantas, Children's Mercy Hospitals and Clinics, Kansas City, MO, United States; Matt hall, Children's Hospital Association, Lenexa, KS, United States; Sian Best, Children's Mercy Hospitals and Clinics, Kansas City, MO, United States; Jessica Bettenhausen, Children’s Mercy, Prairie Village, KS, United States; Shelby Chesbro, Children’s Mercy Kansas City, Kansas City, MO, United States; Kathryn E.. Kyler, Children's Mercy Hospitals and Clinics, Kansas City, MO, United States; Kyle Langford, Children's Mercy Hospitals and Clinics, Leawood, KS, United States; Maria Newmaster, Children's Mercy Hospitals and Clinics, Kansas City, MO, United States; Laura Plencner, Children's Mercy Kansas City, Prairie Village, KS, United States; Hank Puls, Children's Mercy Kansas City, Kansas City, KS, United States; Smit Shah, Children's Mercy Hospitals and Clinics, kansas city, MO, United States; Amanda Sirotzki, Children's Mercy Hospitals and Clinics, Pleasant Valley, MO, United States; Makenna Steger, Children's Mercy Hospitals and Clinics, Kansas City, MO, United States; Jacqueline M.. Walker, Children's Mercy Hospitals and Clinics, Overland Park, KS, United States; Jessica Markham, Children's Mercy Hospitals and Clinics, Kansas City, MO, United States

Background: Staphylococcus aureus is estimated to cause < 10% of complicated community-acquired pneumonia (cCAP) cases, but >70% of U.S. children’s hospitals use empiric Methicillin resistant S. aureus (MRSA) antibiotic coverage for this condition. Despite molecular diagnostic testing’s (MDT) superior pathogen detection over culture methods, how hospitals use MDT and its impact on antibiotic stewardship and clinical outcomes for cCAP are unknown.

Objective: Our objectives were to examine national variation in MDT use for pediatric patients hospitalized with cCAP and to compare MRSA antibiotic coverage, length of stay, and cost according to testing modality.

Design/Methods: We performed a retrospective study of children 60 days to 18 years old hospitalized with cCAP between 2021-2024 using the Pediatric Health Systems Information System database. Exclusion criteria included complex chronic conditions, receipt of antifungals/antivirals, transfers to other hospitals, death, and hospitals with incomplete annual data. We examined the proportion of children receiving bacterial cultures (blood or pleural fluid), broad-spectrum MDT (plasma cell-free DNA metagenomic next-generation sequencing, also known as Karius, and 16s ribosomal RNA PCR), and targeted MDT (S. aureus and Streptococcus pneumoniae PCR). We used K-means clustering to group hospitals into 4 clusters based on the proportion of broad-spectrum and target MDT use: 1) low broad-spectrum and low targeted, 2) low broad-spectrum and high targeted, 3) high broad-spectrum and low targeted and 4) high broad-spectrum and high targeted MDT. Generalized estimating equations determined associations between testing group and outcomes adjusting for payor, intensive care unit admission, and severity.

Results: There were 2994 hospitalizations across 43 hospitals: 98.5% had a culture, 26.2% broad-spectrum, and 44.2% targeted MDT ordered. Broad-spectrum MDT use ranged from 9.2% to 90.7% and targeted MDT use from 12.7% to 80.2% across the 4 groups (Figure 1). MRSA antibiotic use ranged from 67% to 93% (Table 1). In adjusted models, there was no difference in cost or length of stay among the 4 groups. The group with low broad-spectrum and high targeted MDT use had lower MRSA antibiotic use when compared to the group with low broad-spectrum and low targeted MDT (RR 0.34 [95% CI] 0.17-0.67, p=0.002; Figure 2).

Conclusion(s): Hospitals with low broad-spectrum and high targeted MDT use had lower MRSA antibiotic use with no increase in costs or length of stay. Targeted MDT may be a useful tool in cCAP antibiotic stewardship.

Table 1. Characteristics of included encounters.
Table 1 - Characteristics of included encounters.pdfH-RISK: Hospitalization Resource Intensity Scores for Kids1, ICU: intensive care unit, IQR: inter-quartile range, MDT: molecular diagnostic testing, MRSA: Methicillin resistant Staphylococcus aureus, y: years; 1Richardson T, Rodean J, Harris M, Berry J, Gay JC, Hall M. Development of Hospitalization Resource Intensity Scores for Kids (H-RISK) and Comparison across Pediatric Populations. J Hosp Med. 2018;13(9):602-608. doi:10.12788/jhm.2948

Figure 1. Clustering of hospitals based on the proportion of broad-spectrum and targeted molecular diagnostic testing (MDT)
Figure 1 - Hospital clusters based on MDT.pdf

Figure 2. Clinical and utilization outcomes by hospital cluster of molecular diagnostic testing (MDT) patterns.
Figure 2 - OR outcomes by cluster.pdf