Bone Anchor Fixation in the Repair of Blunt Traumatic Abdominal Wall Hernias: A Western Trauma Association Multicenter Study.

BACKGROUND: Blunt traumatic abdominal wall hernias (TAWHs) are rare but require a variety of operative techniques to repair including bone anchor fixation (BAF) when tissue tears off bony structures. This study aimed to provide a descriptive analysis of BAF technique for blunt TAWH repair. Bone anchor fixation and no BAF repairs were compared, hypothesizing increased hernia recurrence with BAF repair. METHODS: A secondary analysis of the WTA blunt TAWH multicenter study was performed including all patients who underwent repair of their TAWH. Patients with BAF were compared to those with no BAF with bivariate analyses. RESULTS: 176 patients underwent repair of their TAWH with 41 (23.3%) undergoing BAF. 26 (63.4%) patients had tissue fixed to bone, with 7 of those reinforced with mesh. The remaining 15 (36.6%) patients had bridging mesh anchored to bone. The BAF group had a similar age, sex, body mass index, and injury severity score compared to the no BAF group. The time to repair (1 vs 1 days, P = .158), rate of hernia recurrence (9.8% vs 12.7%, P = .786), and surgical site infection (SSI) (12.5% vs 15.6%, P = .823) were all similar between cohorts. CONCLUSIONS: This largest series to date found nearly one-quarter of TAWH repairs required BAF. Bone anchor fixation repairs had a similar rate of hernia recurrence and SSI compared to no BAF repairs, suggesting this is a reasonable option for repair of TAWH. However, future prospective studies are needed to compare specific BAF techniques and evaluate long-term outcomes including patient-centered outcomes such as pain and quality of life.

Increasing the Rate of Venous Thromboembolism Chemoprophylaxis Administration Using the Electronic Medical Record.

Introduction: Venous thromboembolism (VTE) remains a leading cause of preventable harm among hospitalized patients. Pharmacologic VTE prophylaxis reduces the rate of in-hospital VTE by 60%, but medication administration is often missed for various reasons. Electronic medical record (EMR) prompts may be a useful tool to decrease withholding of critical VTE chemoprophylaxis medications. Methods: In August 2021, an EMR prompt was implemented at a tertiary referral academic medical center mandating nursing staff to contact a provider for approval before withholding VTE chemoprophylaxis. A pre-intervention group from August 2020 to August 2021 was compared to a post-intervention group from August 2021 to August 2022. Rates of VTE chemoprophylaxis withholding were compared between the groups with a P < .01 considered significant. Results: A total of 16,395 patients prescribed VTE chemoprophylaxis were reviewed, with 13,395 (81.7%) receiving low molecular weight heparin. Of the 16,395 patients included, 10,701 (65.3%) were medical and 5694 (34.7%) were surgical. Patients in the pre-intervention cohort (n = 8803) and post-intervention cohort (n = 7592) were similar in hospital length of stay and duration of DVT prophylaxis. In the post-intervention group, the frequency of surgical patients with at least one missed dose had increased by 4.2% (P = .002), with the trauma and acute care surgery (TACS) show an increase of 6.6% (P < .001). However, the frequency of medical patients and non-TACS patients with missed doses decreased by 3.1% (P = .002) and 1.0% (<.001), respectively. Conclusions: EMR prompts appear to be a low-cost intervention that increases the rate of VTE prophylaxis administration among medical and elective surgery patients.

Breast Cancer Method of Detection: 5-Year Outcomes Across a Multisite Health Care Enterprise.

PURPOSE: To investigate the feasibility and accuracy of radiologists categorizing the method of detection (MOD) when performing image-guided breast biopsies. METHODS: This retrospective, observational study was conducted across a health care enterprise that provides breast imaging services at 18 imaging sites across four US states. Radiologists used standardized templates to categorize the MOD, defined as the first test, sign, or symptom that triggered the subsequent workup and recommendation for biopsy. All image-guided breast biopsies since the implementation of the MOD-inclusive standardized template-from October 31, 2017 to July 6, 2023-were extracted. A random sample of biopsy reports was manually reviewed to evaluate the accuracy of MOD categorization. RESULTS: A total of 29,999 biopsies were analyzed. MOD was reported in 29,423 biopsies (98.1%) at a sustained rate that improved over time. The 10 MOD categories in this study included the following: 15,184 mammograms (51.6%); 4,561 MRIs (15.5%); 3,473 ultrasounds (11.8%); 2,382 self-examinations (8.1%); 2,073 tomosynthesis studies (7.0%); 432 clinical examinations (1.5%); 421 molecular breast imaging studies (1.4%); 357 other studies (1.2%); 338 contrast-enhanced digital mammograms (1.1%); and 202 PET studies (0.7%). Original assignments of the MOD agreed with author assignments in 87% of manually reviewed biopsies (n = 100, 95% confidence interval: [80.4%, 93.6%]). CONCLUSIONS: This study demonstrates that US radiologists can consistently and accurately categorize the MOD over an extended time across a health care enterprise.

A western trauma association multicenter comparison of mesh versus non-mesh repair of blunt traumatic abdominal wall hernias.

BACKGROUND: Blunt traumatic abdominal wall hernias (TAWH) occur in <1 % of trauma patients. Optimal repair techniques, such as mesh reinforcement, have not been studied in detail. We hypothesize that mesh use will be associated with increased surgical site infections (SSI) and not improve hernia recurrence. MATERIALS AND METHODS: A secondary analysis of the Western Trauma Association blunt TAWH multicenter study was performed. Patients who underwent TAWH repair during initial hospitalization (1/2012-12/2018) were included. Mesh repair patients were compared to primary repair patients (non-mesh). A logistic regression was conducted to assess risk factors for SSI. RESULTS: 157 patients underwent TAWH repair during index hospitalization with 51 (32.5 %) having mesh repair: 24 (45.3 %) synthetic and 29 (54.7 %) biologic. Mesh patients were more commonly smokers (43.1 % vs. 22.9 %, p = 0.016) and had a larger defect size (10 vs. 6 cm, p = 0.003). Mesh patients had a higher rate of SSI (25.5 % vs. 9.5 %, p = 0.016) compared to non-mesh patients, but a similar rate of recurrence (13.7 % vs. 10.5%, p = 0.742), hospital length of stay (LOS), and mortality. Mesh use (OR 3.66) and higher ISS (OR 1.06) were significant risk factors for SSI in a multivariable model. CONCLUSION: Mesh was used more frequently in flank TAWH and those with a larger defect size. Mesh use was associated with a higher incidence and risk of SSI but did not reduce the risk of hernia recurrence. When repairing TAWH mesh should be employed judiciously, and prospective randomized studies are needed to identify clear indications for mesh use in TAWH.

Panmixia in the American eel extends to its tropical range of distribution: Biological implications and policymaking challenges.

The American eel (Anguilla rostrata) has long been regarded as a panmictic fish and has been confirmed as such in the northern part of its range. In this paper, we tested for the first time whether panmixia extends to the tropical range of the species. To do so, we first assembled a reference genome (975 Mbp, 19 chromosomes) combining long (PacBio and Nanopore and short (Illumina paired-end) reads technologies to support both this study and future research. To test for population structure, we estimated genotype likelihoods from low-coverage whole-genome sequencing of 460 American eels, collected at 21 sampling sites (in seven geographic regions) ranging from Canada to Trinidad and Tobago. We estimated genetic distance between regions, performed ADMIXTURE-like clustering analysis and multivariate analysis, and found no evidence of population structure, thus confirming that panmixia extends to the tropical range of the species. In addition, two genomic regions with putative inversions were observed, both geographically widespread and present at similar frequencies in all regions. We discuss the implications of lack of genetic population structure for the species. Our results are key for the future genomic research in the American eel and the implementation of conservation measures throughout its geographic range. Additionally, our results can be applied to fisheries management and aquaculture of the species.

Cholesterol granuloma of the breast: A case report.

Cholesterol granuloma of the breast is a rare entity that can be indistinguishable from cancer on physical exam and imaging. We present the case of a 58-year-old woman who developed a new enhancing mass on high-risk screening magnetic resonance imaging (MRI). Interestingly, this mass developed in the same area as a previously noted benign-appearing inflammatory cyst that had been decreasing in size on MRI and mammogram over many years. Ultrasound-guided biopsy was performed which revealed cholesterol granuloma. We will discuss the nonspecific imaging findings and the characteristic histopathological features that confirm diagnosis.

Hypofibrinogenemic Massive Transfusion Trauma Patients Experience Worse Outcomes.

INTRODUCTION: Uncontrolled hemorrhage accounts for up to 40% of trauma-related mortality. Previous reports demonstrate that decreased fibrinogen levels during traumatic hemorrhage are associated with worse outcomes. Cryoprecipitate is used to replace fibrinogen for patients in hemorrhagic shock undergoing massive transfusion (MT), though the optimal ratio of cryoprecipitate to fresh frozen plasma (FFP), packed red blood cells (PRBCs), and platelets remains undefined. The purpose of this study is to investigate the effect of admission fibrinogen level and the use of cryoprecipitate on outcomes in trauma patients undergoing MT. METHODS: A prospective practice management guideline was established to obtain fibrinogen levels on adult trauma patients undergoing MT at a level I trauma center from December 2019 to December 2021. Ten units of cryoprecipitate were administered every other round of MT. Thromboelastography (TEG) was also obtained at the initiation and completion of MT. Patient demographic, injury, transfusion, and outcome data were collected. Hypofibrinogenemic (<200 mg/dL) patients at initiation of MT were compared to patients with a level of 200 mg/dL or greater. RESULTS: A total of 96 out of 130 patients met criteria and underwent MT with a median admission fibrinogen of 170.5 mg/dL. Hypofibrinogenemia was associated with elevated INR (1.26 vs 1.13, P < .001) and abnormal TEG including decreased alpha angle (68.1 vs 73.3, P < .001), increased K time (1.7 vs 1.1, P < .001), and decreased max amplitude (58 vs 66, P < .001). Patients with hypofibrinogenemia received more PRBC (10 vs 7 U, P = .002), FFP (9 vs 6 U, P = .003), and platelets (2 vs 1 U, P = .004) during MT. Hypofibrinogenemic patients demonstrated greater mortality than patients with normal levels (50% vs 23.5%, P = .021). Older age, decreased GCS, and elevated injury severity score (ISS) were risk factors for mortality. Increased fibrinogen was associated with lower odds of mortality (P = .001). Age, ISS, and fibrinogen level remained significantly associated with mortality in a multivariable analysis. Overall, fibrinogen in post-MT survivors showed an increase in median level compared to admission (231 vs 177.5 mg/dL, P < .001). CONCLUSION: Trauma patients undergoing MT with decreased admission fibrinogen demonstrate increased mortality. Other mortality risk factors include older age, decreased GCS, and higher ISS. Patients with increased fibrinogen levels had lower odds of mortality in a multivariable model. Post-MT survivors demonstrated significantly higher fibrinogen levels than pre-MT patients. Hypofibrinogenemic patients also had worse TEG parameters and required more PRBCs, FFP, and platelets during MT. Further studies are needed to assess the optimal volume of fibrinogen replacement with cryoprecipitate during MT to improve trauma patient mortality.

Methicillin-Resistant Staphylococcus aureus Nasal Swab Is Insufficient to Withhold Empiric Methicillin-Resistant Staphylococcus aureus Pneumonia Coverage in a Trauma Population.

INTRODUCTION: Methicillin-resistant staphylococcus aureus (MRSA) nasal colonization is a predictor of MRSA pneumonia in intensive care unit (ICU) patients. Negative nasal swabs have shown up to a 97% negative predictive value for MRSA pneumonia in nontrauma populations, though little investigation has been pursued in trauma patients. MATERIALS AND METHODS: All trauma patients admitted to the ICU from April 2018 to February 2019 were screened for MRSA colonization by nasal swab. Patients with suspicion for pneumonia underwent bronchoalveolar lavage or quantitative sputum culture and were started on empiric antibiotic therapy based on the swab result. Swab-positive patients were started on empiric MRSA coverage and swab-negative patients were not. RESULTS: MRSA nasal swab screening was performed in 601 trauma ICU patients. Ninety-six patients subsequently underwent pneumonia workup and were started on an empiric antibiotic regimen based on nasal swab results. Seventeen (17.7%) patients were MRSA nasal swab positive on screening, and 22 (22.9%) patients subsequently had significant growth of MRSA on quantitative respiratory culture. The sensitivity of nasal swab was 50.0% and the specificity was 91.9%. Eleven patients had a negative MRSA nasal swab but a positive MRSA pneumonia (11.5%). Patients with inadequate antibiotic coverage had statistically longer hospital length of stay, ICU length of stay, ventilator days, and rates of unplanned intubation compared to patients with adequate antibiotic coverage. CONCLUSIONS: Nasal swab screening was not sensitive enough in a trauma population with a high endemic incidence of MRSA colonization to warrant withholding empiric antibiotic MRSA coverage in patients with suspected pneumonia.

Risk factors for recurrence in blunt traumatic abdominal wall hernias: A secondary analysis of a Western Trauma association multicenter study.

BACKGROUND: Few studies have investigated risk factors for recurrence of blunt traumatic abdominal wall hernias (TAWH). METHODS: Twenty trauma centers identified repaired TAWH from January 2012 to December 2018. Logistic regression was used to investigate risk factors for recurrence. RESULTS: TAWH were repaired in 175 patients with 21 (12.0%) known recurrences. No difference was found in location, defect size, or median time to repair between the recurrence and non-recurrence groups. Mesh use was not protective of recurrence. Female sex, injury severity score (ISS), emergency laparotomy (EL), and bowel resection were associated with hernia recurrence. Bowel resection remained significant in a multivariable model. CONCLUSION: Female sex, ISS, EL, and bowel resection were identified as risk factors for hernia recurrence. Mesh use and time to repair were not associated with recurrence. Surgeons should be mindful of these risk factors but could attempt acute repair in the setting of appropriate physiologic parameters.

Early pneumonia diagnosis decreases ventilator-associated pneumonia rates in trauma population.

BACKGROUND: Ventilator-associated pneumonia (VAP) is a source of morbidity and mortality for trauma patients. Aspiration events are also common because of traumatic brain injury, altered mental status, or facial trauma. In patients requiring mechanical ventilation, early pneumonias (EPs) may be erroneously classified as ventilator associated. METHODS: A prospective early bronchoscopy protocol was implemented from January 2020 to January 2022. Trauma patients intubated before arrival or within 48 hours of admission underwent bronchoalveolar lavage (BAL) within 24 hours of intubation. Patients with more than 100,000 colony-forming units on BAL were considered to have EP. RESULTS: A total of 117 patients underwent early BAL. Ninety-three (79.5%) had some growth on BAL with 36 (30.8%) meeting criteria for EP. For the total study population, 29 patients (24.8%) were diagnosed with VAP later in their hospital course, 12 of which had previously been diagnosed with EP. Of EP patients (n = 36), 21 (58.3%) were treated with antibiotics based on clinical signs of infection. Of EP patients who had a later pneumonia diagnosed by BAL (n = 12), seven (58.3%) grew the same organism from their initial BAL. When these patients were excluded from VAP calculation, the rate was reduced by 27.6%. Patients with EP had a higher rate of smoking history (41.7% vs. 19.8%, p < 0.001) compared with patients without EP. There was no difference in median hospital length of stay, intensive care unit length of stay, ventilator days, or mortality between the two cohorts. CONCLUSION: Early pneumonia is common in trauma patients intubated within the first 48 hours of admission and screening with early BAL identifies patients with aspiration or pretraumatic indicators of pneumonia. Accounting for these patients with early BAL significantly reduces reported VAP rates. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.

Analysis of Admission Thromboelastogram Profiles in 1369 Male and Female Trauma Patients.

INTRODUCTION: Recent studies have demonstrated a hypercoagulable thromboelastrogram (TEG) in female trauma patients compared with males, conferring a possible survival advantage. We hypothesized that TEG profiles would reveal a relative hypercoagulable state in female compared with male trauma patients. METHODS: A prospective review was conducted on all adult trauma patients admitted to the trauma service at an American College of Surgeons-verified level I trauma center from December 2019 to June 2021 who, per our institutional protocol, received a thrombelastotgraphy on their initial arrival to the trauma center if classified as a level I or II trauma activation. The thromboelastography values of male and female trauma patients were compared as the primary outcome variables of interest. The secondary outcomes investigated were hospital length of stay, surgical interventions, and ventilatory requirement. RESULTS: A total of 1369 patients met inclusion criteria, with 878 (64.1%) male and 491 (35.9%) female. Female patients had a higher median alpha angle (74.8 versus 72.6°, P < 0.001), maximum amplitude (69.3 versus 66.2 mm, P < 0.001), and shorter median K time (1.0 versus 1.2 s, P < 0.001). Female patients had a shorter hospital length of stay (4 versus 5 d, P < 0.001), had a lower rate of surgical intervention (14.6% versus 25.5%, P < 0.001), and had lower rates of mechanical ventilation (19.3% versus 39.5%, P < 0.001). CONCLUSIONS: Female trauma patients were found to have hypercoagulable indices on TEG at the time of initial trauma evaluation compared with males. Intrinsic differences in sex coagulation profiles should be further investigated to optimize modern resuscitation strategies.

Muscular variant presenting as an asymmetry on mammogram.

Anatomic variants in chest wall musculature can pose a potential diagnostic dilemma when visible on a mammogram. A few variants have been commonly reported in the literature and can be confidently identified by appearance and location. We present a case of a pectoralis muscle variant, not previously described in radiology literature that presented as a unilateral asymmetry on a screening mammogram. This article reviews common imaging appearances of muscular variants seen mammographically and provides a diagnostic algorithm to avoid unnecessary workup or biopsy.

Routine Lower Extremity Screening Ultrasound Protocols in Trauma Patients Are Not Cost Effective.

BACKGROUND: Despite prophylaxis, deep vein thrombosis (DVT) and pulmonary embolism remain dreaded complications following traumatic injury and are associated with significant morbidity and mortality. Screening ultrasound (US) protocols have been employed in trauma centers for early detection of lower extremity (LE) deep venous thrombosis. We hypothesized that screening lower extremity venous duplex US would not prove cost effective in our trauma population who receives early pharmacologic prophylaxis. METHODS: Data was collected for one year on all adult trauma patients admitted to the trauma service from December 2019 to 2020. DVT screening US was obtained at 3 days after admission for patients with long bone or pelvic fracture, spinal cord injury, immobility, and/or spinal fracture requiring surgery. Screening US was obtained at 7 days for all others and repeated weekly until discharge. Data was retrospectively collected and analyzed. RESULTS: Exactly 1365 patients met inclusion criteria with median ISS 12 (IQR, 9-17), median age 56 (IQR, 36-73 years), and with majority blunt injuries (90.7%). A total of 1369 screening US were performed finding 27 DVTs (2%). The total cost of screening for the year analyzed amounted to over $270,000 with 50.7 screening US needed to detect 1 DVT. This resulted in an average screening cost of over $10,000 for the detection of a single DVT. DISCUSSION: In trauma patients receiving early pharmacologic prophylaxis, routine LE screening US protocols to detect LE DVT are not cost effective.

Traumatic brain injury patients with platelet inhibition receiving platelet transfusion demonstrate decreased need for neurosurgical intervention and decreased mortality.

BACKGROUND: Platelet dysfunction is known to occur in patients with traumatic brain injury (TBI), and the correction of platelet dysfunction may prevent hemorrhagic progression in TBI. Thromboelastography with platelet mapping (TEG-PM; Haemonetics) evaluates the degree of platelet function inhibition through the adenosine diphosphate (ADP) and arachidonic acid (AA) pathways. We hypothesized that ADP and AA inhibition would improve with the transfusion of platelets in patients with TBI. METHODS: A retrospective review was conducted at a Level I trauma center of all patients presenting with TBI from December 2019 to December 2020. Per a practice management guideline, a platelet mapping assay was obtained on all patients with TBI upon admission. If ADP or AA was found to be inhibited (>60%), the patient was transfused 1 unit of platelets and a repeat platelet mapping assay was ordered. Demographic data, laboratory values, and outcomes were analyzed. RESULTS: Over the 13-month study period, 453 patients with TBI underwent TEG-PM with a protocol adherence rate of 66.5% resulting in a total of 147 patients who received platelets for ADP and/or AA inhibition; of those, 107 underwent repeat TEG-PM after platelets were administered. With the administration of platelets, ADP (p < 0.0001), AA (p < 0.0001), and MA (p = 0.0002) all significantly improved. Of 330 patients with TBI not taking antiplatelet medications, 50.9% showed inhibition in ADP and/or AA. If AA or ADP inhibition was noted on admission, mortality was increased (p = 0.0108). If ADP improved with platelet administration, the need for neurosurgical intervention was noted to decrease (p = 0.0182). CONCLUSION: Patients with TBI and platelet inhibition may benefit from the administration of platelets to correct platelet dysfunction. Thromboelastography with platelet mapping may be implemented in the initial workup of patients presenting with TBI to assess platelet dysfunction and provide prognostic information, which may guide treatment. LEVEL OF EVIDENCE: Therapeutic / Care Management, level III.

Abbreviated Molecular Breast Imaging: Feasibility and Future Considerations.

OBJECTIVE: Molecular breast imaging (MBI) is a supplemental screening modality consistently demonstrating incremental cancer detection over mammography alone; however, its lengthy duration may limit widespread utilization. The study purpose was to assess feasibility of an abbreviated MBI protocol, providing readers with mediolateral oblique (MLO) projections only and assessing performance in lesion detection and localization. METHODS: Retrospective IRB-exempt blinded reader study administered to 5 fellowship-trained breast imaging radiologists. Independent reads performed for 124 screening MBI cases, half abnormal and half negative/normal. Readers determined whether an abnormality was present, side of abnormality, and location of abnormality (medial/lateral). Abnormal cases had confirmatory biopsy or surgical pathology; normal cases had imaging follow-up ensuring true negative results. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated to assess performance. A false negative result indicated that a reader failed to detect abnormal uptake; a false positive result indicated a reader incorrectly called an abnormality for a negative case. Tests for association included chi-square, Fisher-exact, and analysis of variance. RESULTS: Mean reader performance for detecting abnormal uptake: sensitivity 96.8%, specificity 98.7%, PPV 98.8%, and NPV 96.9%. Accuracy in localizing lesions to the medial or lateral breast was 100%. There were no associations in reader performance with reader experience, reader technique, lesion morphology, or lesion pathology. Median lesion size was 1.0 cm (range: 0.4-8.0 cm). All readers correctly identified 97.7% (42/43) of lesions with malignant or elevated risk pathology. CONCLUSION: An abbreviated MBI protocol (MLO images only) maintained high accuracy in lesion detection and localization.

Management of blunt traumatic abdominal wall hernias: A Western Trauma Association multicenter study.

BACKGROUND: Blunt traumatic abdominal wall hernias (TAWH) occur in approximately 15,000 patients per year. Limited data are available to guide the timing of surgical intervention or the feasibility of nonoperative management. METHODS: A retrospective study of patients presenting with blunt TAWH from January 2012 through December 2018 was conducted. Patient demographic, surgical, and outcomes data were collected from 20 institutions through the Western Trauma Association Multicenter Trials Committee. RESULTS: Two hundred and eighty-one patients with TAWH were identified. One hundred and seventy-six (62.6%) patients underwent operative hernia repair, and 105 (37.4%) patients underwent nonoperative management. Of those undergoing surgical intervention, 157 (89.3%) were repaired during the index hospitalization, and 19 (10.7%) underwent delayed repair. Bowel injury was identified in 95 (33.8%) patients with the majority occurring with rectus and flank hernias (82.1%) as compared with lumbar hernias (15.8%). Overall hernia recurrence rate was 12.0% (n = 21). Nonoperative patients had a higher Injury Severity Score (24.4 vs. 19.4, p = 0.010), head Abbreviated Injury Scale score (1.1 vs. 0.6, p = 0.006), and mortality rate (11.4% vs. 4.0%, p = 0.031). Patients who underwent late repair had lower rates of primary fascial repair (46.4% vs. 77.1%, p = 0.012) and higher rates of mesh use (78.9% vs. 32.5%, p < 0.001). Recurrence rate was not statistically different between the late and early repair groups (15.8% vs. 11.5%, p = 0.869). CONCLUSION: This report is the largest series and first multicenter study to investigate TAWHs. Bowel injury was identified in over 30% of TAWH cases indicating a significant need for immediate laparotomy. In other cases, operative management may be deferred in specific patients with other life-threatening injuries, or in stable patients with concern for bowel injury. Hernia recurrence was not different between the late and early repair groups. LEVEL OF EVIDENCE: Therapeutic/care management, Level IV.

Characterizing Risk Factors for Clostridioides difficile Infection among Hospitalized Patients with Community-Acquired Pneumonia.

Hospitalized patients with community-acquired pneumonia (CAP) are at risk of developing Clostridioides difficile infection (CDI). We developed and tested clinical decision rules for identifying CDI risk in this patient population. The study was a single-center retrospective, case-control analysis of hospitalized adult patients empirically treated for CAP between 1 January 2014 and 3 March 2018. Differences between cases (CDI diagnosed within 180 days following admission) and controls (no test result indicating CDI during the study period) with respect to prehospitalization variables were modeled to generate propensity scores. Postadmission variables were used to predict case status on each postadmission day where (i) ≥1 additional case was identified and (ii) each model stratum contained ≥15 subjects. Models were developed and tested using optimal discriminant analysis and classification tree analysis. Forty-four cases and 181 controls were included. The median time to diagnosis was 50 days postadmission. After weighting, three models were identified (20, 117, and 165 days postadmission). The day 20 model yielded the greatest (weighted [w]) accuracy (weighted area under the receiver operating characteristic curve [wROC area] = 0.826) and the highest chance-corrected accuracy (weighted effect strength for sensitivity [wESS] = 65.3). Having a positive culture (odds, 1:4; P = 0.001), receipt of ceftriaxone plus azithromycin for a defined infection (odds, 3:5; P = 0.006), and continuation of empirical broad-spectrum antibiotics with activity against P. aeruginosa when no pathogen was identified (odds, 1:8; P = 0.013) were associated with CDI on day 20. Three models were identified that accurately predicted CDI in hospitalized patients treated for CAP. Antibiotic use increased the risk of CDI in all models, underscoring the importance of antibiotic stewardship.