The utility of sepsis scores for predicting blood stream infections in extracorporeal membrane oxygenation.

INTRODUCTION: Extracorporeal membrane oxygenation (ECMO) is an increasingly used modality of life support with high risk for nosocomial infections. The accuracy of sepsis prediction tools in identifying blood stream infections (BSI) in this population is unknown as measurement of multiple variables commonly associated with infection are altered by the circuit. METHODS: This study compares all blood stream infections for patients receiving ECMO between January 2012 and December 2020 to timepoints when blood cultures were negative using the Sequential Organ Failure Assessment (SOFA), Logistic Organ Dysfunction Score (LODS), American Burn Association Sepsis Criteria (ABA), Systemic Inflammatory Response Syndrome (SIRS) scores. RESULTS: Of the 220 patients who received ECMO during the study period, 40 (18%) had 51 blood stream infections and were included in this study. Gram-positive infections composed 57% (n = 29) of infections with E. faecalis (n = 12, 24%) being the most common organism isolated. There were no significant differences in sepsis prediction scores at the time of infection compared to infection-free time points for SOFA (median (IQR) 7 (5-9) vs. 6 (5-8), p = 0.22), LODS (median (IQR) 12 (10-14) vs. 12 (10-13), p = 0.28), ABA (median (IQR) 2 (1-3) vs. 2 (1-3) p = 0.75), or SIRS (median (IQR) 3 (2-3) vs. 3 (2-3), p = 0.20). CONCLUSIONS: Our data shows that previously published sepsis scores are elevated throughout a patient's ECMO course, and do not correlate with bacteremia. Better predictive tools are needed to determine the appropriate timing for blood cultures in this population.

Evaluation of the Infectious Diseases Society of America's Core Antimicrobial Stewardship Curriculum for Infectious Diseases Fellows.

BACKGROUND: Antimicrobial stewardship (AS) programs are required by Centers for Medicare and Medicaid Services and should ideally have infectious diseases (ID) physician involvement; however, only 50% of ID fellowship programs have formal AS curricula. The Infectious Diseases Society of America (IDSA) formed a workgroup to develop a core AS curriculum for ID fellows. Here we study its impact. METHODS: ID program directors and fellows in 56 fellowship programs were surveyed regarding the content and effectiveness of their AS training before and after implementation of the IDSA curriculum. Fellows' knowledge was assessed using multiple-choice questions. Fellows completing their first year of fellowship were surveyed before curriculum implementation ("pre-curriculum") and compared to first-year fellows who complete the curriculum the following year ("post-curriculum"). RESULTS: Forty-nine (88%) program directors and 105 (67%) fellows completed the pre-curriculum surveys; 35 (64%) program directors and 79 (50%) fellows completed the post-curriculum surveys. Prior to IDSA curriculum implementation, only 51% of programs had a "formal" curriculum. After implementation, satisfaction with AS training increased among program directors (16% to 68%) and fellows (51% to 68%). Fellows' confidence increased in 7/10 AS content areas. Knowledge scores improved from a mean of 4.6 to 5.1 correct answers of 9 questions (P = .028). The major hurdle to curriculum implementation was time, both for formal teaching and for e-learning. CONCLUSIONS: Effective AS training is a critical component of ID fellowship training. The IDSA Core AS Curriculum can enhance AS training, increase fellow confidence, and improve overall satisfaction of fellows and program directors.

Investing in the Future: A Role for Professional Societies to Prepare the Next Generation of Healthcare Leaders Through Curriculum Development and Dissemination.

Professional societies serve many functions that benefit constituents; however, few professional societies have undertaken the development and dissemination of formal, national curricula to train the future workforce while simultaneously addressing significant healthcare needs. The Infectious Diseases Society of America (IDSA) has developed 2 curricula for the specific purpose of training the next generation of clinicians to ensure the future infectious diseases (ID) workforce is optimally trained to lead antimicrobial stewardship programs and equipped to meet the challenges of multidrug resistance, patient safety, and healthcare quality improvement. A core curriculum was developed to provide a foundation in antimicrobial stewardship for all ID fellows, regardless of career path. An advanced curriculum was developed for ID fellows specifically pursuing a career in antimicrobial stewardship. Both curricula will be broadly available in the summer of 2021 through the IDSA website.

Improvement in adherence to antibiotic duration of therapy recommendations for uncomplicated cystitis: a quasi-experimental study.

BACKGROUND: Acute uncomplicated cystitis is one of the most common diagnoses for which antibiotic treatment is prescribed in the outpatient setting. Despite the availability of national guidelines, there remains a wide pattern in prescriber choices for therapy. Recent data portray a picture of consistently longer durations than recommended prescribed in outpatient settings. OBJECTIVE: The objective was to evaluate the effect of a system-based intervention on adherence to guideline-recommended durations of therapy for uncomplicated cystitis in the outpatient setting. METHODS: This quasi-experimental study included women aged 18-64 years who were seen at five family medicine clinics at an academic medical centre and were prescribed targeted antibiotics for uncomplicated cystitis (nitrofurantoin monohydrate/macrocrystals 100 mg, trimethoprim-sulfamethoxazole 160/800 mg or ciprofloxacin 250 mg). The intervention involved revising or adding pre-filled, but modifiable, default prescribing instructions in the electronic health record (EHR) for the targeted antibiotics. We evaluated adherence to guideline-recommended duration of therapy as well as days of therapy (DOT) before and after the intervention. RESULTS: A total of 787 pre-intervention and 862 post-intervention cases were included. Adherence to recommended duration of therapy increased from 29.4% to 76.3% (P < 0.01). The average DOT decreased by 23% from 6.6 to 5.1 (P < 0.01). CONCLUSION: A stewardship intervention consisting of revising/adding default prescribing instructions to targeted antimicrobials in an EHR was associated with increased adherence to recommended durations of therapy for uncomplicated cystitis and reduction of unnecessary antibiotic exposure. More studies are needed to confirm effectiveness across multiple medical record platforms.

Evaluation of the trends and appropriateness of fluoroquinolone use in the outpatient treatment of acute uncomplicated cystitis at five family practice clinics.

WHAT IS KNOWN AND OBJECTIVE: Despite recommendations to avoid fluoroquinolones (FQs) as a first-line treatment for uncomplicated cystitis, recent data suggest that FQs remain widely prescribed. Therefore, the objectives of this study were to evaluate the appropriateness of empiric FQ use compared to nitrofurantoin for uncomplicated cystitis and to determine whether there are any trends or predictors of empiric FQ versus nitrofurantoin use for uncomplicated cystitis. METHODS: This retrospective study included women ages 19-64 years who were seen at five family medicine clinics and were prescribed targeted antibiotics (nitrofurantoin, ciprofloxacin or levofloxacin) for uncomplicated cystitis. Charts were reviewed to collect data, including symptoms, comorbidities, allergies, creatinine clearance, recent antibiotic use and urine culture data. Appropriateness of empiric selection was determined based on national guidelines and local susceptibility data. RESULTS AND DISCUSSION: A total of 677 patient encounters were screened for inclusion. Of those, 567 met the inclusion criteria: 395 nitrofurantoin and 172 FQs. Treatment was considered appropriate in 86.8% and 10.5% of cases that were prescribed nitrofurantoin and FQs, respectively (P < .01). There were four independent predictors of FQ use identified by multivariate logistical regression: clinic at which the patient was treated, age, nitrofurantoin use within 90 days prior to encounter and previous urine culture within one year with an organism non-susceptible to nitrofurantoin. WHAT IS NEW AND CONCLUSION: Despite recommendations against FQs for uncomplicated cystitis, they continue to be widely prescribed, and their use for this indication is often inappropriate. This highlights the need for additional interventions and education to improve use and preserve the utility of FQs.

Factors Influencing Selection of Infectious Diseases Training for Military Internal Medicine Residents.

Background: Applications to infectious diseases fellowships have declined nationally; however, the military has not experienced this trend. In the past 6 years, 3 US military programs had 58 applicants for 52 positions. This study examines military resident perceptions to identify potential differences in factors influencing career choice, compared with published data from a nationwide cohort. Methods: An existing survey tool was adapted to include questions unique to the training and practice of military medicine. Program directors from 11 military internal medicine residencies were asked to distribute survey links to their graduating residents from December 2016 to January 2017. Data were categorized by ID interest. Result: The response rate was 51% (n = 68). Of respondents, 7% were ID applicants, 40% considered ID but reconsidered, and 53% were uninterested. Of those who considered ID, 73% changed their mind in their second and third postgraduate years and cited salary (22%), lack of procedures (18%), and training length (18%) as primary deterrents to choosing ID. Active learning styles were used more frequently by ID applicants to learn ID concepts than by those who considered or were uninterested in ID (P = .02). Conclusions: Despite differences in the context of training and practice among military trainees compared with civilian colleagues, residents cited similar factors affecting career choice. Interest in global health was higher in this cohort. Salary continues to be identified as a deterrent to choosing ID. Differences between military and civilian residents' desire to pursue ID fellowship are likely explained by additional unmeasured factors deserving further study.

Antimicrobial Stewardship Training for Infectious Diseases Fellows: Program Directors Identify a Curriculum Need.

A needs assessment survey of infectious diseases (ID) training program directors identified gaps in educational resources for training and evaluating ID fellows in antimicrobial stewardship. An Infectious Diseases Society of America-sponsored core curriculum was developed to address that need.

Clinical infectious outcomes associated with biofilm-related bacterial infections: a retrospective chart review.

BACKGROUND: Biofilms are associated with persistent infection. Reports characterizing clinical infectious outcomes and patient risk factors for colonization or infection with biofilm forming isolates are scarce. Our institution recently published a study examining the biofilm forming ability of 205 randomly selected clinical isolates. This present study aims to identify potential risk factors associated with these isolates and assess clinical infectious outcomes. METHODS: 221 clinical isolates collected from 2005 to 2012 and previously characterized for biofilm formation were studied. Clinical information from the associated patients, including demographics, comorbidities, antibiotic usage, laboratory values, and clinical infectious outcomes, was determined retrospectively through chart review. Duplicate isolates and non-clinical isolates were excluded from analysis. Associations with biofilm forming isolates were determined by univariate analysis and multivariate analysis. RESULTS: 187 isolates in 144 patients were identified for analysis; 113 were biofilm producers and 74 were not biofilm producers. Patients were primarily male (78 %) military members (61 %) with combat trauma (52 %). On multivariate analysis, the presence of methicillin-resistant Staphylococcus aureus (p < 0.01, OR 5.09, 95 % CI 1.12, 23.1) and Pseudomonas aeruginosa (p = 0.02, OR 3.73, 95 % CI 1.46, 9.53) were the only characteristics more likely to be present in the biofilm producing isolate group. Infectious outcomes of patients with non-biofilm forming isolates, including cure, relapse/reinfection, and chronic infection, were similar to infectious outcomes of patients with biofilm-forming isolates. Mortality with initial infection was higher in the biofilm producing isolate group (16 % vs 5 %, p = 0.01) but attributable mortality was low (1 of 14). No characteristics examined in this study were found to be associated with relapse/reinfection or chronic infection on multivariate analysis. CONCLUSIONS: Bacteria species, but not clinical characteristics, were associated with biofilm formation on multivariate analysis. Biofilm forming isolates and non-biofilm forming isolates had similar infectious outcomes in this study.

Dirofilaria presenting as orbital mass.

Dirofilaria is a common roundworm infection of dogs, cats, raccoons, and other animals that is commonly referred to as "heartworm." The genus Dirofilaria includes D. immitis, which is a common cause of animal disease in the western hemisphere and primarily manifests as pulmonary lesions in humans, and D. repens, which is the more common causative agent of animal disease in Eurasia and primarily results in subcutaneous and ocular lesions in humans. Humans are accidental end hosts, with infection resulting from bites by mosquitoes of the Culicidae family in which ingested microfilaria have matured to infectious larvae.

Variations of CHROMagar Acinetobacter to detect imipenem-resistant Acinetobacter baumannii-calcoaceticus complex.

BACKGROUND: Acinetobacter baumannii-calcoaceticus complex (ABC) isolates are often multidrug-resistant, including to carbapenems. Chromogenic media can facilitate the rapid detection of Gram-negative bacteria, often with the addition of supplements to a base chromogenic medium to detect resistance. We examined various combinations of available media to detect imipenem resistance among 107 ABC clinical isolates. METHODS: CHROMagar Orientation, CHROMagar KPC, and CHROMagar Acinetobacter, by itself, with Acinetobacter supplement, with KPC supplement, or CHROMagar Acinetobacter with increasing concentrations (1, 2.5, and 5 ml/l) of a new CR102 supplement, were examined. RESULTS: Sensitivity for the detection of isolates was high (> 98%) for all formulations. Specificity was high for CHROMagar Acinetobacter with 2.5 ml/l and 5 ml/l of the CR102 supplement, at 95.3% and 97.7%, respectively, with positive predictive values of 97% and 98.5%. Negative predictive values of these 2 formulations were 100%. CONCLUSIONS: CHROMagar Acinetobacter with the addition of the CR102 supplement at 2.5 ml/l and 5ml/l is highly sensitive and specific for the detection of imipenem-resistant ABC, and may be useful for the rapid detection of imipenem-resistant ABC in clinical samples.

A Multidisciplinary Approach to Improvements in Perioperative Antibiotic Prophylaxis at a Military Treatment Facility.

INTRODUCTION: Surgical site infections complicate 2%-5% of surgeries. According to the Centers for Disease Control and Prevention, half of all surgical site infections are preventable. Adherence to published recommendations regarding perioperative antibiotic administration decreases the incidence of surgical site infections. Members of the Department of Anesthesia noticed casual observations of inaccurate prescribing of antibiotics at our institution, Brooke Army Medical Center, and approached the Antimicrobial Stewardship Program to collaborate on this issue. MATERIALS AND METHODS: A team of anesthesiologists, clinical pharmacists, and infectious disease specialists collaborated with the Department of Surgery to improve this effort as part of a multiyear project from 2018 to 2021. We first assessed adherence to recommended perioperative antibiotic use to establish a baseline and next, noticing gaps, created a project with the goal to improve compliance to >90% across surveyed measures. Our key interventions included educational initiatives, creation of facility-specific guidelines, peer benchmarking, updating order sets, interdisciplinary collaboration, creation of intraoperative reminders and visual aids, and tailored presentations to selected services. RESULTS: Of 292 charts (2.3% of cases from January to October 2018) reviewed pre-intervention, compliance rates were 84% for antibiotic choice, 92% for dose, 65% for redosing, and 71% for postoperative administration. Of doses, 100% were timed correctly, and thus, this variable was not targeted. Post-intervention, our review of 387 charts (10% of cases from May to November 2020) showed no change in correct antibiotic choice (84%) and statistical improvement to 96% for correct dose, 95% for correct redosing, and 85% for correct postoperative administration (P < .05 for all). CONCLUSIONS: Our multidisciplinary approach of collaboration with multiple departments, creating guidelines and providing feedback, improved compliance with perioperative antibiotic administration recommendations.

Prolonged Survival Following Intra-abdominal Mycobacterium abscessus Infection Without Antimicrobial Therapy or Surgical Intervention.

Management of Mycobacterium abscessus infection involves prolonged multidrug antibiotic therapy with surgical resection indicated in extensive disease and abscesses. We report a case of post-surgical intra-abdominal M. abscessus infection with prolonged survival and radiographic resolution without intervention. A 51-year-old female who had a prolonged hospital stay with multiple surgeries following a complicated laparoscopic sleeve gastrectomy developed multiple M. abscessus intra-abdominal and abdominal wall abscesses with cutaneous fistulae. She was started on a multidrug antibiotic regimen. However, the patient terminated the regimen after 4 weeks due to intolerable side effects and was transitioned to hospice care. She showed steady clinical improvement with radiographic resolution of the abscesses over the next year. In the context of the limited understanding of these infections, our finding is notable, given that in this period, she avoided potential hospitalizations, life altering side effects of prolonged antimicrobial therapy, and complications from more surgeries.

Evaluation of a two step testing algorithm to improve diagnostic accuracy and stewardship of Clostridioides difficile infections.

In response to national guidelines, we implemented a two-step testing algorithm for Clostridioides difficile in an effort to improve diagnostic accuracy. Following implementation, we analyzed treatment frequency between discordant and concordant patients. We found that the majority of discordant cases were treated with no significant differences in patient characteristics or outcomes between the concordant and discordant groups. Additionally, there were no differences in outcomes when discordant patients were further stratified by treatment status. Given little added diagnostic accuracy with the addition of EIA toxin testing, our facility resumed diagnosis by PCR testing alone. Further studies are needed to investigate alternative processes for improvement in diagnostic accuracy aside from toxin EIA testing including stool submission criteria and educational programs.

Treatment and outcome of gram-positive bacteremia in patients receiving extracorporeal membrane oxygenation.

BACKGROUND: While guidance exists for management of blood stream infections with various invasive devices, there are currently limited data to guide antibiotic selection and duration for bacteremia in patients receiving extracorporeal membrane oxygenation (ECMO). OBJECTIVE: To evaluate the treatment and outcomes of thirty-six patients with Staphylococcus aureus and Enterococcus bacteremia on ECMO support. METHODS: Blood culture data was retrospectively analyzed from patients with Staphylococcus aureus bacteremia (SAB) or Enterococcus bacteremia who underwent ECMO support between March 2012 and September 2021 at Brooke Army Medical Center. RESULTS: Of the 282 patients who received ECMO during this study period, there 25 (9%) patients developed Enterococcus bacteremia and 16 (6%) developed SAB. SAB occurred earlier in ECMO as compared to Enterococcus (median day 2 IQR (1-5) vs. 22 (12-51), p = 0.01). The most common duration of antibiotics was 28 days after clearance for SAB and 14 days after clearance for Enterococcus. 2 (5%) patients underwent cannula exchange with primary bacteremia, and 7 (17%) underwent circuit exchange. 1/3 (33%) patients with SAB and 3/10 (30%) patients with Enterococcus bacteremia who remained cannulated after completion of antibiotics had a second episode of SAB or Enterococcus bacteremia. CONCLUSION: This single center case series is the first to describe the specific treatment and outcomes of patients receiving ECMO complicated by SAB and Enterococcus bacteremia. For patients who remain on ECMO after completion of antibiotics, there is a risk of a second episode of Enterococcus bacteremia or SAB.

Inclusion, Diversity, Access, and Equity in Infectious Diseases Fellowship Training: Tools for Program Directors.

The Infectious Diseases Society of America (IDSA) has set clear priorities in recent years to promote inclusion, diversity, access, and equity (IDA&E) in infectious disease (ID) clinical practice, medical education, and research. The IDSA IDA&E Task Force was launched in 2018 to ensure implementation of these principles. The IDSA Training Program Directors Committee met in 2021 and discussed IDA&E best practices as they pertain to the education of ID fellows. Committee members sought to develop specific goals and strategies related to recruitment, clinical training, didactics, and faculty development. This article represents a presentation of ideas brought forth at the meeting in those spheres and is meant to serve as a reference document for ID training program directors seeking guidance in this area.

Infectious Disease Teleconsultation to the Deployed U.S. Military From 2017-2022.

INTRODUCTION: The ADvanced VIrtual Support for OpeRational Forces (ADVISOR) program is a synchronous telemedicine system developed in 2017 to provide 24/7 remote expert support to U.S. Military and NATO clinicians engaged in medical care in austere locations. Infectious disease (ID) remains the highest consulted service since 2018 and is currently staffed by 10 adult and pediatric ID physicians within the Military Health System. We conducted a retrospective review of the ID ADVISOR calls between 2017 and 2022 to identify trends and better prepare military ID physicians to address urgent ID consultations in overseas settings. METHODS: Health records of the ID consultations between July 2017 and January 2022 were reviewed for local caregiver and patient demographics, case descriptions, consultant recommendations, and outcomes. A "not research" determination was made by the Brooke Army Medical Center Human Research Protections Office. RESULTS: ID physicians received 57 calls for 60 urgent patient consultations. Most calls were from countries in the Middle East or in Southwest Asia (United States Central Command (USCENTCOM)), followed by countries in Africa (United States Africa Command (USAFRICOM)). The majority of patients were active duty U.S. Military and were generally male with median age of 25 years. All consults involved an initial phone consultation and 30% continued over email. Ninety percent of the calls were initiated by physicians, and the median time from injury or illness-onset to consult was 3 days. Seventy percent of the consult questions involved treatment and further diagnostics, but one-third of cases required assistance with management of disease prevention. Multidrug-resistant or nosocomial infections, animal or bite exposure, malaria and malaria prevention, febrile illness, and blood-borne pathogen exposure accounted for 63% of the consults. Collaboration with other specialties took place in a minority of cases, and follow-up contact was recommended 20% of the time. Most recommendations involved adjusting drug regimens or further testing. Medical evacuation was only recommended in five of the cases. Although there was limited ability for follow-up, no known deaths occurred. CONCLUSIONS: A high proportion of calls to the ID ADVISOR line are relevant to the overlapping content areas of infection prevention, force protection, and outbreak response. Most patients requiring urgent ID consultation were managed successfully without evacuation. The current military-unique ID fellowship curriculum is consistent with the encountered diagnoses per the ID ADVISOR line, and high-yield individual topics have been identified.

Rates of nosocomial infection associated with interhospital transfer of patients receiving extracorporeal membrane oxygenation.

OBJECTIVES: Critically ill patients requiring extracorporeal membrane oxygenation (ECMO) frequently require interhospital transfer to a center that has ECMO capabilities. Patients receiving ECMO were evaluated to determine whether interhospital transfer was a risk factor for subsequent development of a nosocomial infection. DESIGN: Retrospective cohort study. SETTING: A 425-bed academic tertiary-care hospital. PATIENTS: All adult patients who received ECMO for >48 hours between May 2012 and May 2020. METHODS: The rate of nosocomial infections for patients receiving ECMO was compared between patients who were cannulated at the ECMO center and patients who were cannulated at a hospital without ECMO capabilities and transported to the ECMO center for further care. Additionally, time to infection, organisms responsible for infection, and site of infection were compared. RESULTS: In total, 123 patients were included in analysis. For the primary outcome of nosocomial infection, there was no difference in number of infections per 1,000 ECMO days (25.4 vs 29.4; P = .03) by univariate analysis. By Cox proportional hazard analysis, transport was not significantly associated with increased infections (hazard ratio, 1.7; 95% confidence interval, 0.8-4.2; P = .20). CONCLUSION: In this study, we did not identify an increased risk of nosocomial infection during subsequent hospitalization. Further studies are needed to identify sources of nosocomial infection in this high-risk population.

Aminoglycoside resistance and susceptibility testing errors in Acinetobacter baumannii-calcoaceticus complex.

Antimicrobial resistance is depleting the pharmacopeia of agents clinically useful against Gram-negative bacilli. As the number of active agents diminishes, accurate susceptibility testing becomes critical. We studied the susceptibilities of 107 isolates of the Acinetobacter baumannii-calcoaceticus complex to amikacin, gentamicin, and tobramycin using disk diffusion, Etest, as well as the Phoenix, Vitek 2, and MicroScan automated systems, and compared the results to those obtained by broth microdilution. Genes encoding aminoglycoside-modifying enzymes (AMEs) were detected by multiplex PCR, and clonal relationships were determined by pulsed-field gel electrophoresis. Tobramycin was the most active aminoglycoside (27.1% of isolates were susceptible). Disk diffusion and Etest tended to be more accurate than the Vitek 2, Phoenix, and MicroScan automated systems; but errors were noted with all methods. The Vitek 2 instrument incorrectly reported that more than one-third of the isolates were susceptible to amikacin (a very major error). Isolates were polyclonal, with 26 distinct strains, and carried multiple AME genes unrelated to the strain type. The presence of the ant(2")-Ia gene was statistically associated with resistance to each aminoglycoside. The AME genotype accounted for the resistance profile observed in a minority of isolates, suggesting the involvement of multiple resistance mechanisms. Hospital pharmacy records indicated the preferential use of amikacin over other aminoglycosides in the burn intensive care unit, where aminoglycoside resistance is prevalent. The resistance in that unit did not correlate with a predominant strain, AME genotype, or total annual aminoglycoside consumption. Susceptibility to tobramycin increased, even though susceptible isolates carried AME genotypes predicting the inactivation of tobramycin. Determination of the relative contribution of multiple concurrent resistance mechanisms may improve our understanding of aminoglycoside resistance in the Acinetobacter baumannii-calcoaceticus complex.

Antimicrobial Stewardship Challenges in the Deployed Setting.

INTRODUCTION: Up to 34% of combat trauma injuries are complicated by infection with multidrug-resistant organisms. Overutilization of antibiotics has been linked to increased multidrug-resistant organisms in combat-injured patients. Antimicrobial stewardship efforts at deployed medical treatment facilities have been intermittently reported; however; a comprehensive assessment of antimicrobial stewardship practices has not been performed. MATERIALS AND METHODS: A survey tool was modified to include detailed questions on antimicrobial stewardship practices at medical treatment facilities. A Joint Service, multidisciplinary team conducted on-site assessments and interviews to assess the status of antimicrobial stewardship best practices, with particular emphasis on antibiotic prophylaxis in combat injured, in the U.S. Central Command operational theaters. Limitations to implementing stewardship to the national standards were explored thematically. RESULTS: Nine Role 1, 2, and 3 medical facilities representing the range of care were assessed on-site. A total of 67% of the sites reported a formal antimicrobial stewardship program and 56% of the sites had an assigned head of antimicrobial stewardship. No military personnel in theater received training on antimicrobial stewardship and laboratory assets were limited. Personnel at these sites largely had access to Joint Trauma System guidelines describing antimicrobial prophylaxis for combat injured (89%), yet infrequently received feedback on their implementation and adherence to these guidelines (11%). CONCLUSIONS: Antimicrobial stewardship programs in theater are in the early stages of development in theater. Areas identified for improvement are access to expertise, development of a focus on high-impact lines of effort, laboratory support, and the culture of antimicrobial prescribing. Risks can be mitigated through theater level formalization of efforts, expert mentoring through telehealth, and a focus on implementation and adherence and feedback to national guidelines.