Prophylactic Antibiotics and Multi-Drug-Resistant Organism Infections in Older Patients with Intracranial Hemorrhage

Authors:
Henry Olivera Perez, Anna Huang Perez, Andrea Gochi, Rachel Borthwell, Jackelyn Moya, Emily Quinn, Annie Wong-on-Wing, Vivian Ng, Savinnie Ho, Isaac Mora, Saffanat Sumra, Adam Gutierrez, Genna Beattie, Naveen Balan, Lucas Thornblade, Gregory Victorino, April Mendoza

Body of Abstract:
Background

The prevalence of older patients with traumatic intracranial hemorrhage (tICH) is increasing. Multidrug-resistant organism (MDRO) infections can contribute to the morbidity and mortality these patients face. Current literature on rates and risk factors for MDRO infections in this population is limited. We hypothesize that among older patients with tICH who developed in-hospital infections, the use of prophylactic antibiotics for associated injuries will be associated with higher rates of MDRO speciation.

Methods

A retrospective review was conducted of patients 65 years and older at a Level 1 trauma center from 2017-2025 who presented with tICH and developed an in-hospital infection requiring treatment with antibiotics. Patients with contaminated cultures and/or no documented clinical evidence of infection were excluded. Demographics, antibiotic regimens, and culture data was collected for all patients. χ2 and Fisher’s exact tests were used for categorical variables and Wilcoxon rank-sum tests were used for continuous variables.

Results

Sixty-seven patients met inclusion criteria. These patients were predominantly male (67%) with a median age of 74. Median Injury Severity Score was 26. Fifty-four patients (81%) developed pneumonia, 22 (33%) developed a urinary tract infection, and 12 (18%) developed bacteremia. One (1%) developed a craniectomy site infection. Twenty-three (34%) developed multiple infections. Fourteen patients (21%) received prophylactic antibiotics for meningitis and/or osteomyelitis prevention in the setting of orthopedic or neurosurgical injuries for a median duration of 1.5 days. Fourteen patients (21%) developed an MDRO infection. Median time to culture-proven infection was 6 days for both MDRO and non-MDRO patients (p = 0.9). The most common MDRO in respiratory cultures was methicillin-resistant Staphylococcus aureus (MRSA) (n=6, 50%). Only 2 patients (22%) developed MDRO from a urinary source. Patients who received prophylactic antibiotics trended towards higher rates of MDRO speciation (39% vs 17% p = 0.09). Patients who underwent craniectomy/craniotomy were more likely to develop MDRO infections than non-surgical patients (64% vs 31% p = 0.02).

Conclusion

Older patients with tICH who received prophylactic antibiotics trended toward higher rates of MDRO infections. Prophylactic antibiotics and its effect on MDRO infection rate in this patient population should be further investigated.