Evaluation of Actinomyces Species Infection in a Surgical Population

Sunday, March 22, 2026

9:45 AM - 10:45 AM Central Time

Location: Connections Central - RST 05

Ann Margaret Routon, PharmD

University of Kentucky HealthCare, Kentucky

Disclosure(s): No relevant financial relationship(s) to disclose.
MM

Morgan Michas, PharmD, BCCCP

Emergency Medicine Pharmacist
University of Kentucky HealthCare

Disclosure information not submitted.
KR

Kathryn Ruf, PharmD

Director of the Office of Pharmacy Value and Analytics
University of Kentucky HealthCare

Disclosure information not submitted.
JB

Jacqueline Bishop, PharmD

Trauma/ Emergency General Surgery Pharmacist
University of Kentucky HealthCare

Disclosure information not submitted.
AW

Ali Wiegand, BCCCP, PharmD

Trauma/ Emergency General Surgery Pharmacist
University of Kentucky College of Medicine

Disclosure information not submitted.
RM

Ryan Mynatt, PharmD

Infectious Diseases & Outpatient Parenteral Antimicrobial Therapy Clinical Pharmacist
University of Kentucky HealthCare

Disclosure information not submitted.
DA

Dina Ali, PharmD

Epic Pharmacist Program Coordinator
University of Kentucky HealthCare

Disclosure information not submitted.

Introduction: Actinomyces species are anaerobic, Gram positive bacteria that typically colonize the human mucosa and can cause rare but serious infections. Due to high culture failure rate, diagnosis and appropriate treatment duration are imperative but remain uncertain. A recent quality improvement study at the University of Kentucky HealthCare revealed an increase in Actinomyces species infections within the surgical population.

Methods: This retrospective, single-center study evaluated adult surgical patients with interventional cultures positive for Actinomyces species between June 2021 and April 2024. Data collection included demographics, surgical services, antimicrobial treatment, and infectious diseases (ID) consultations.

Results: Of 184 patients identified and screened, 84 were included for analysis. The median age was 55 years [IQR 43–64], and median length of stay was 11 days [IQR 5–22.5]. Readmissions within 90 days occurred in 18% of patients. During the index encounter, 80 patients (95.2%) had antibiotic orders active against Actinomyces species with a median duration of 6.7 days [IQR 4-13], however, only 68 patients (80.95%) were discharged on appropriate therapy with a median duration of 20 days [IQR 10-86]. ID follow up was scheduled for 33% of patients, but only 48% attended their appointments. Patients without a gap in therapy had a longer median duration of 14 days [IQR 7-60] vs 62 days [IQR 10.75-187] for patients with gaps in therapy. At discharge, the most common antibiotics prescribed were aminopenicillins (54.2%). Gaps in antibiotic therapy were reported in 30 patients (35.7%). Among these, the median duration of the gap in therapy at the time of discharge was 35 days [IQR, 19.3–52.8].

Conclusions: Although 80% of patients were treated with appropriate antimicrobial therapy during index encounter, most patients did not receive appropriate antimicrobial therapy at discharge. This inappropriate therapy and duration lead to the need for institutional protocols and improved outpatient follow up in managing Actinomyces infections.