Abstract
Background
We aim to investigate the incidence, clinical presentation, management, and outcome of infections due to Actinotignum species observed at Mayo Clinic Rochester over the last 5 years.
Methods
We searched the clinical microbiology laboratory database to identify isolates of Actinotignum spp. from all body sites between January 1, 2014 and December 31, 2018.
Results
Fifty-four patients with positive culture with Actinotignum were identified. Mean age was 67 years and 27 (50%) had an underlying urogenital condition. Actinotignum was isolated in 26 urine cultures, 6 blood cultures, 12 abscess fluid cultures, and 10 bone/joint tissue cultures (Table 1). Fifteen (28%) specimens were monomicrobial while 39 (72%) were polymicrobial. Recovery from urine cultures was interpreted as colonization in 11 (20%) cases. Of the 54 patients with positive cultures, 43 patients had Actinotignum-associated clinical infection; 15 (35%) with urinary tract infections (11 with cystitis and 4 with pyelonephritis), 12 (28%) with abscesses (skin, intraabdominal, and surgical site infections), 10 (23%) with bone/joint infection, and 6 (14%) with bacteremia (Table 2). Most frequently isolated species was A. schaalii (n = 40); followed by 2 cases of A. sanguinis. Susceptibility testing (n = 40) showed that all stains were susceptible to penicillin (MIC< = 0.5), 36% were susceptible to clindamycin (MIC < = 2) and 10% susceptible to metronidazole (MIC < = 8). There was no recurrence of Actinotignum-related infections in any of the treated cases. Two patients with bone/joint infection underwent repeat surgical intervention due to worsening infection while on antibiotic treatment prior to resolution of infection. There was 1 death in a patient with bacteremia (polymicrobial) who had presented with a massive stroke (Table 3).
Conclusion
A. schaalii was most commonly associated with urinary tract infections followed by abscesses and bone/joint infections in elderly population. Majority of the infections were polymicrobial. All tested isolated were susceptible to penicillin; however, resistance was frequent for clindamycin and metronidazole. All appropriately treated patients had resolution of infection without recurrence from Actinotignum, except for one patient with bacteremia who died from massive stroke
Disclosures
All authors: No reported disclosures.
Session: 243. Bacterial Diagnostics
Saturday, October 5, 2019: 12:15 PM



