Predictors of irritable bowel syndrome-like symptoms in quiescent inflammatory bowel disease

BACKGROUND

Many patients with quiescent inflammatory bowel disease (IBD) suffer from irritable bowel syndrome (IBS)-like symptoms. Although these symptoms cause significant reductions in quality of life, evidence-based treatments are lacking as risk factors and pathophysiology of these symptoms are not clearly defined. We aimed to identify risk factors for development of IBS-like symptoms in IBD patients with quiescent disease.

METHODS

We performed a single-center retrospective cohort study of adults with IBD from 2015 to 2021. Quiescent IBD was defined by a fecal calprotectin level <250 μg/g of stool or endoscopic evidence of quiescent disease. Cox regression was performed to identify variables that were independently associated with the incident development of IBS-like symptoms in IBD patients.

KEY RESULTS

A total of 368 IBD patients were included for analysis, including 278 patients with UC and 88 with Crohn's disease. 15.5% of quiescent IBD patients developed IBS symptoms, with an incidence rate of (95% CI 48.0-82.0) 63.3 per 1000 person-years. In the multivariate model, mood disorders (including anxiety and depression) and Crohn's disease were associated with increased risk for developing IBS symptoms. Male sex and higher iron levels conferred lower risk for developing IBS symptoms. Results from the multivariable model were similar in sensitivity analysis with quiescent IBD defined by fecal calprotectin level <150 mcg/g.

CONCLUSIONS & INFERENCES

Mood disorder and Crohn's disease were positively associated with IBS-like symptoms in quiescent IBD, whereas male sex and iron levels were protective. Our results were robust to different fecal calprotectin levels, arguing against inflammation as a mechanism for IBS-like symptoms. This data suggests noninflammatory mechanisms may be important in the pathogenesis of IBS-like symptoms in quiescent IBD. Future work may address whether modifying these risk factors may alter disease course.

A quasi-experimental study of a bundled diagnostic stewardship intervention for ventilator-associated pneumonia

OBJECTIVES

Diagnostic error in the use of respiratory cultures for ventilator-associated pneumonia (VAP) fuels misdiagnosis and antibiotic overuse within intensive care units. In this prospective quasi-experimental study (NCT05176353), we aimed to evaluate the safety, feasibility, and efficacy of a novel VAP-specific bundled diagnostic stewardship intervention (VAP-DSI) to mitigate VAP over-diagnosis/overtreatment.

METHODS

We developed and implemented a VAP-DSI using an interruptive clinical decision support tool and modifications to clinical laboratory workflows. Interventions included gatekeeping access to respiratory culture ordering, preferential use of non-bronchoscopic bronchoalveolar lavage for culture collection, and suppression of culture results for samples with minimal alveolar neutrophilia. Rates of adverse safety outcomes, positive respiratory cultures, and antimicrobial utilization were compared between mechanically ventilated patients (MVPs) in the 1-year post-intervention study cohort (2022-2023) and 5-year pre-intervention MVP controls (2017-2022).

RESULTS

VAP-DSI implementation did not associate with increases in adverse safety outcomes but did associate with a 20% rate reduction in positive respiratory cultures per 1000 MVP days (pre-intervention rate 127 [95% CI: 122-131], post-intervention rate 102 [95% CI: 92-112], p < 0.01). Significant reductions in broad-spectrum antibiotic days of therapy per 1000 MVP days were noted after VAP-DSI implementation (pre-intervention rate 1199 [95% CI: 1177-1205], post-intervention rate 1149 [95% CI: 1116-1184], p 0.03).

DISCUSSION

Implementation of a VAP-DSI was safe and associated with significant reductions in rates of positive respiratory cultures and broad-spectrum antimicrobial use. This innovative trial of a VAP-DSI represents a novel avenue for intensive care unit antimicrobial stewardship. Multicentre trials of VAP-DSIs are warranted.

Identification and Characterization of Immune Checkpoint Inhibitor-Induced Toxicities From Electronic Health Records Using Natural Language Processing

PURPOSE

Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment, yet their use is associated with immune-related adverse events (irAEs). Estimating the prevalence and patient impact of these irAEs in the real-world data setting is critical for characterizing the benefit/risk profile of ICI therapies beyond the clinical trial population. Diagnosis codes, such as International Classification of Diseases codes, do not comprehensively illustrate a patient's care journey and offer no insight into drug-irAE causality. This study aims to capture the relationship between ICIs and irAEs more accurately by using augmented curation (AC), a natural language processing-based innovation, on unstructured data in electronic health records.

METHODS

In a cohort of 9,290 patients treated with ICIs at Mayo Clinic from 2005 to 2021, we compared the prevalence of irAEs using diagnosis codes and AC models, which classify drug-irAE pairs in clinical notes with implied textual causality. Four illustrative irAEs with high patient impact-myocarditis, encephalitis, pneumonitis, and severe cutaneous adverse reactions, abbreviated as MEPS-were analyzed using corticosteroid administration and ICI discontinuation as proxies of severity.

RESULTS

For MEPS, only 70% (n = 118) of patients found by AC were also identified by diagnosis codes. Using AC models, patients with MEPS received corticosteroids for their respective irAE 82% of the time and permanently discontinued the ICI because of the irAE 35.9% (n = 115) of the time.

CONCLUSION

Overall, AC models enabled more accurate identification and assessment of patient impact of ICI-induced irAEs not found using diagnosis codes, demonstrating a novel and more efficient strategy to assess real-world clinical outcomes in patients treated with ICIs.

Standards for fecal microbiota transplant: Tools and therapeutic advances

Fecal microbiota transplantation (FMT) has been demonstrated to be efficacious in preventing recurrent Clostridioides difficile (C. difficile) infections, and is being investigated for treatment of several other diseases including inflammatory bowel disease, cancer, obesity, liver disease, and diabetes. To speed up the translation of FMT into clinical practice as a safe and standardized therapeutic intervention, additional evidence-based technical and regulatory guidance is needed. To this end in May of 2022, the International Alliance for Biological Standardization (IABS) and the BIOASTER Microbiology Technology Institute hosted a second webinar to discuss key issues still impeding the advancement and standardization of FMT. The goal of this two-day webinar was to provide a forum for scientific experts to share and discuss data and key challenges with one another. Discussion included a focus on the evaluation of safety, efficacy, clinical trial design, reproducibility and accuracy in obtained microbiome measurements and data reporting, and the potential for standardization across these areas. It also focused on increasing the application potential and visibility of FMT beyond treating C. difficile infections.

Urinary bother, Urinalysis, and Two-Year Efficacy Follow-Up Results of Phase I Trial of Intravesical Bacillus Calmette-Guérin Combined with Intravenous Pembrolizumab in Recurrent or Persistent High-Grade Non-Muscle-Invasive Bladder Cancer after Previous Bacillus Calmette-Guérin Treatment

OBJECTIVE

To report urinary bother, urinalysis changes, disease-free survival (DFS), and overall survival (OS) over 2 years for subjects enrolled in a phase I dose-escalation trial (NCT02324582) of intravesical Bacillus Calmette-Guérin (BCG) in combination with systemic pembrolizumab for recurrent or persistent high-grade non-muscle invasive bladder cancer (HGNMIBC).

METHODS

Eighteen patients consented to the study. Five were screen failures. Clinical activity was determined using cystoscopy and cytology with a biopsy of suspicious lesions. Urinalysis and International Prostate symptom score were assessed at pre-treatment, Week 10 (during combined BCG and pembrolizumab treatment), and 3 and 6 months from treatment completion. IPSS was analyzed using a mixed-model repeated measures analysis. A Chi-square test was used to compare urinalysis results at each interval.

RESULTS

The pathologic disease stage after restaging transurethral resection and before treatment was pTa in 6 (46.2%), CIS in 6 (46.2%), and pT1 in 1 (7.7%). There was no increase in reported urinary bother throughout treatment. Quality of life measurements demonstrated no change in subjective burden. On urinalysis, we did not observe significant differences at 3 months compared to baseline evaluation. At 12 months, the DFS and OS were 69.23% and 92.31%, respectively. At 24 months, the DFS and OS were 38.46% and 92.31%, respectively.

CONCLUSIONS

Treatment with BCG combined with intravenous pembrolizumab is not showing increased urinary bother or adverse urinalysis changes. Two-year response data is promising and await confirmation in the phase III study (Keynote 676).

An Open-Label, Randomized Trial Comparing Fidaxomicin With Oral Vancomycin for the Treatment of Clostridioides difficile Infection in Hospitalized Patients Receiving Concomitant Antibiotics for Concurrent Infections

BACKGROUND

Recurrent Clostridioides difficile infection (rCDI) occurs frequently, and concomitant antibiotic (CA) during the initial episode for treatment of non-CDI is a major risk factor. We sought to address the comparative efficacy of fidaxomicin versus vancomycin in the setting of CA during the initial CDI episode.

METHODS

We conducted a randomized, controlled, open-label trial at 2 hospitals in Ann Arbor, Michigan. We consecutively consented and enrolled hospitalized patients ≥18 years old with diarrhea, a positive test for C. difficile, and ≥1 qualifying CA. Complicated CDI, CDI treatment for >24 hours prior to enrollment, and planned long-term (>12 weeks) CA use were notable exclusions. Clinical cure was defined as resolution of diarrhea for 2 consecutive days maintained until 2 days after therapy, and rCDI as recurrent diarrhea with positive testing ≤30 days after initial treatment. Patients were randomized to fidaxomicin or vancomycin.

RESULTS

Baseline characteristics were similar in the 2 groups of 144 patients. Rates of clinical cure (73% vs 62.9%, P = .195) and rCDI (3.3% vs 4.0%; P > .99) were similar for fidaxomicin and vancomycin in the intention-to-treat and per-protocol cohorts, respectively. Only 4 patients developed rCDI.

CONCLUSIONS

In this study of patients with CDI receiving CA, a numerically higher proportion were cured with fidaxomicin versus vancomycin, but this result did not reach statistical significance. Overall recurrence was lower than anticipated in both arms compared with previous studies that did not extend duration of CDI treatment during CA.

CLINICAL TRIALS REGISTRATION

www.clinicaltrials.gov (NCT02692651).

Quality of life following treatment with intra-arterial cisplatin with concurrent radiation and erlotinib for locally advanced head and neck cancer

OBJECTIVES

Studies that focus on the feasibility of using erlotinib plus chemoradiation to treat locally advanced head and neck cancer have given hints of improved survival outcomes compared to chemoradiation alone. However, the influence of this treatment regimen on the quality of life of the patients has not been documented. We conducted a study of this triple combination and now have documented follow-up survival data as well as long-term quality of life (QoL) measures.

METHODS

Three sets of QoL questionnaires were given to patients with a diagnosis of head and neck cancer at two time points, pre- and post-treatment, to assess differences in quality of life after receiving chemotherapy with intra-arterial (IA) cisplatin (150 mg/m2), concomitant radiation (70 Gy), and oral erlotinib (150 mg/day). Additionally, patients were followed for a total of 5 years.

RESULTS

Treatment had a detrimental effect on appearance, taste, and saliva domain scores in their QoL questionnaires. Nonetheless, fewer patients reported pain and anxiety.

SIGNIFICANCE OF RESULTS

The combination of erlotinib with chemoradiation produced similar adverse effects on the QoL scores of patients with head and neck cancer as compared to chemoradiation alone.

Analysis of Gender Dimorphism and Assessment of Racial Variation Through Odontometric Technique: A Cross-Sectional Study

BACKGROUND

When conducting a forensic investigation, one of the most important steps is establishing the biological profile of a victim who cannot be positively recognized or is just a skeleton. It has been shown that, among the other clinical indicators, the diameters of dental crowns are a good and dependable source for determining gender in a particular population sample. However, the literature is sparse regarding their assessment as a viable marker for the determination of a particular race. In addition, the need for population-specific data has also been advocated while determining gender dimorphism based on tooth size.

AIM AND OBJECTIVES

To study the bisexual variation in the permanent dentition of individuals from three different sets of populations: Arabian, South Asian, and East Asian. The other objective is to explore the role of this odontometric analysis in predicting the racial identity of the subjects belonging to the aforementioned population.

METHODOLOGY

The research was conducted at the College of Dentistry, AlJouf University in Sakaka. Measurements of mesiodistal and buccolingual (BL) distances were taken using a digital vernier caliper on a total of 75 pairs of research models or casts. Statistical tests were run on the information gathered.

RESULTS

Of the 75 casts, 38 (50.7%) were of male and 37 (49.3%) were of female. Our analysis showed between genders, a significant difference in maxillary central incisor (P = 0.001), first premolar (P = 0.01), and first molar (P = 0.02) while for a mandibular arch, a significant difference was noted for incisors (P = 0.002) with greater tooth dimension in male than in the female. Concerning the BL dimensions, only the mandibular canine showed a significant difference between males and females (P = 0.001). Comparisons of the crown dimensions between population groups showed that the Arabian population consistently exhibits larger tooth dimensions than the other two populations in both arches.

CONCLUSION

A few crown dimensions can be used as an adjunctive tool for the identification of the gender and race of an individual.

Characteristics of posterior zone I retinopathy of prematurity

OBJECTIVE

To report the demographic profile and clinical characteristics of retinopathy of prematurity (ROP) in posterior Zone I.

METHODS

In a partly retrospective (ten years) and partly prospective (one year) study, we analysed the demographic profile and clinical characteristics of babies with ROP in posterior Zone I.

RESULTS

The study included 130 eyes of 67 infants with a mean gestational age and birth weight of 29.3 (±2.2) weeks and 1217.3 (±381.9) grams, respectively. All babies had received unblended oxygen. In 47 of 51 (91.1%) babies, the weekly weight gain was <100 g (details were not available in 16 babies). The ROP subtypes included aggressive, threshold, hybrid, stage 4, and atypical types in 78 (60%), 20 (15.4%), 11 (8.5%), 15 (11.5%), and 6 (4.6%) eyes, respectively. Fibrovascular proliferation, when present, was prominent nasally, occasionally overriding the disc margin. Extensive arteriovenous tortuosity was more prominent than vascular dilatation. Atypical observations included bleb-like detachment (6 eyes; 4.6%) and candle wax-like preretinal deposits (23 eyes; 17.7%).

CONCLUSIONS

Retinopathy of Prematurity in posterior Zone I in this cohort was strongly associated with 100% unblended oxygen supplementation, poor weight gain, and multiple systemic co-morbidities. ROP in posterior zone 1 has a distinct profile with several atypical characteristics different from ROP in other zones.

Procalcitonin levels in pregnancy: A systematic review and meta-analysis of observational studies

BACKGROUND

The utility of procalcitonin to identify obstetric sepsis is unknown.

OBJECTIVE

To calculate the mean (range) procalcitonin in pregnancy among healthy women not in labor (group 1), healthy women in labor (group 2), and women with preterm prelabor rupture of membranes (PPROM) without clinical chorioamnionitis (group 3).

SEARCH STRATEGY

NLM PubMed, Elsevier Embase, and Wiley Cochrane Central Register of Controlled Trials from inception to February 21, 2022.

SELECTION CRITERIA

Ten or more pregnant women with procalcitonin reported at more than 20 weeks of pregnancy, with information on labor, PPROM, and infection. Exclusions were major medical comorbidities.

DATA COLLECTION AND ANALYSIS

Each abstract and full-text review was independently reviewed by the same two authors. Quality was reviewed using the Newcastle-Ottawa Scale. A meta-analysis was performed using a random effects model.

MAIN RESULTS

The systematic review included 25 studies: 10 (40%) of good quality and 15 (60%) of poor quality. The meta-analysis included 21 studies. Mean procalcitonin in group 1 was 0.092 ng/mL (range 0.036-0.049 ng/mL), in group 2 it was 0.130 ng/mL (range 0.049-0.259 ng/mL), and in group 3 it was 0.345 ng/mL (range 0.005-1.292 ng/mL).

CONCLUSIONS

Among healthy pregnant women not in labor, procalcitonin levels are comparable to those in non-pregnant adults and may be useful in identifying infection. Procalcitonin levels in other groups overlap abnormal values of procalcitonin in non-pregnant adults, and may not discriminate infection among women in labor or with obstetric comorbidities.

PROSPERO

CRD42020157376, registered 4/28/2020.

Association of patient clinical and gut microbiota features with vancomycin-resistant enterococci environmental contamination in nursing homes: a retrospective observational study

BACKGROUND

Preventing transmission is crucial for reducing infections with multidrug-resistant organisms (MDROs) in nursing homes. To identify resident characteristics associated with MDRO spread, we investigated associations between patient characteristics and contamination of their proximate room surfaces with vancomycin-resistant enterococci (VRE).

METHODS

In this retrospective observational study, we used demographic and clinical data (including data on comorbidities, physical independence, catheter use within the past 30 days, and antibiotic exposure within the past 30 days) and surveillance cultures of patient body sites and room surfaces at enrolment and during weekly follow-up visits within the first month, and monthly thereafter (up to 6 months), in six US nursing homes collected in a previous clinical trial (September, 2016, to August, 2018). We did 16S rRNA gene sequencing on perirectal surveillance swabs to investigate the association between the gut microbiota and the culture status of participants and their rooms.

FINDINGS

We included 245 participants (mean age 72·5 years [SD 13·6]; 111 [45%] were men, 134 [55%] were women, 132 [54%] were non-Hispanic white, and 112 [46%] were African American). We collected 2802 participant samples and 5592 environmental samples. At baseline, VRE colonisation was present in 49 (20%) participants, with environmental surfaces being contaminated in 36 (73%) of these patients. Hand contamination among VRE-colonised participants was more common in those with environmental contamination compared with those without (50 [51%] of 99 vs seven [13%] of 55; p<0·0001). We found a correlation between hand contamination and both groin and perirectal colonisation and contamination of various high-touch room surfaces (Cohen's κ 0·43). We found participant microbiota composition to be associated with antibiotic receipt within the past 30 days (high-risk antibiotics p=0·011 and low-risk antibiotics p=0·0004) and participant VRE colonisation status, but not environmental contamination among VRE-colonised participants (participant only vs uncolonised p=0·071, both participant and environment vs uncolonised p=0·025, and participant only vs participant and environment p=0·29). Multivariable analysis to identify independent factors associated with VRE-colonised participants contaminating their environment identified antibiotic exposure (adjusted odds ratio 2·75 [95% CI 1·22-6·16]) and male sex (2·75 [1·24-6·08]) as being associated with increased risk of environmental contamination, and physical dependence as being associated with a reduced risk of environmental contamination (0·91 [0·83-0·99]).

INTERPRETATION

Our data support antibiotic use and interaction with proximal surfaces by physically independent nursing home residents as under-appreciated drivers of environmental contamination among VRE-colonised residents. Integrating resident hand-hygiene education and antimicrobial stewardship will strengthen efforts to reduce MDROs in nursing homes.

FUNDING

US Centers for Disease Control and Prevention, National Institute of Health, Canadian Institutes of Health Research, and University of Michigan.

Clostridioides difficile infection surveillance in intensive care units and oncology wards using machine learning

OBJECTIVE

Screening individuals admitted to the hospital for Clostridioides difficile presents opportunities to limit transmission and hospital-onset C. difficile infection (HO-CDI). However, detection from rectal swabs is resource intensive. In contrast, machine learning (ML) models may accurately assess patient risk without significant resource usage. In this study, we compared the effectiveness of swab surveillance to daily risk estimates produced by an ML model to identify patients who will likely develop HO-CDI in the intensive care unit (ICU) setting.

DESIGN

A prospective cohort study was conducted with patient carriage of toxigenic C. difficile identified by rectal swabs analyzed by anaerobic culture and polymerase chain reaction (PCR). A previously validated ML model using electronic health record data generated daily risk of HO-CDI for every patient. Swab results and risk predictions were compared to the eventual HO-CDI status.

PATIENTS

Adult inpatient admissions taking place in University of Michigan Hospitals' medical and surgical intensive care units and oncology wards between June 6th and October 8th, 2020.

RESULTS

In total, 2,979 admissions, representing 2,044 patients, were observed over the course of the study period, with 39 admissions developing HO-CDIs. Swab surveillance identified 9 true-positive and 87 false-positive HO-CDIs. The ML model identified 9 true-positive and 226 false-positive HO-CDIs; 8 of the true-positives identified by the model differed from those identified by the swab surveillance.

CONCLUSION

With limited resources, an ML model identified the same number of HO-CDI admissions as swab-based surveillance, though it generated more false-positives. The patients identified by the ML model were not yet colonized with C. difficile. Additionally, the ML model identifies at-risk admissions before disease onset, providing opportunities for prevention.

Understanding refugee and immigrant health literacy and beliefs toward antimicrobial resistance

Refugee and migrant populations have increased vulnerability to antimicrobial resistance, yet stewardship guidance is lacking. We addressed this gap through a cross-sectional survey, finding that these populations and immigrants from low and middle-income countries had lower health literacy on the issue compared to native-born Americans and those from high-income countries.

Regional changes in intestinal permeability in cirrhosis are associated with mucosal bacteria

BACKGROUND

Several complications of cirrhosis are theorized to result from the translocation of bacteria or their products across the intestinal epithelium. We aimed to assess epithelial permeability and associations with mucosal bacteria in patients with cirrhosis.

APPROACH AND RESULTS

We collected 247 duodenum, ileum, and colon biopsies from 58 consecutive patients with cirrhosis and 33 controls during clinically indicated endoscopies. Patients with cirrhosis were similarly aged to controls (60 vs. 58 y) and had a median Model for End-stage Liver Disease of 8 (interquartile range 7, 10). Biopsies underwent 16S rRNA-encoding gene amplicon sequencing to determine mucosal bacteria composition and transepithelial electrical resistance (TEER) to determine epithelial permeability. In the entire cohort, there were regional differences in TEER with the lowest TEER (ie, more permeable) in the ileum; duodenum TEER was 43% higher and colon TEER 20% higher than ileum TEER (ANOVA p = 0.0004). When comparing patients with cirrhosis and controls, both TEER (26% lower in cirrhosis, p = 0.006) and alpha diversity differed in the duodenum (27% lower in cirrhosis, p = 0.01) but not ileum or colon. A beta-binomial model found that 26 bacteria were significantly associated with TEER. Bifidobacteriaceae Bifidobacterium in duodenal mucosa was protective of epithelial permeability and future hospitalization for hepatic decompensation.

CONCLUSIONS

Duodenal epithelial permeability was higher, and mucosal bacteria alpha diversity was lower in cirrhosis compared to controls, while no such differences were seen in the ileum or colon. Specific bacteria were associated with epithelial permeability and future hepatic decompensation.

Longitudinal genomic surveillance of carriage and transmission of Clostridioides difficile in an intensive care unit

Despite enhanced infection prevention efforts, Clostridioides difficile remains the leading cause of healthcare-associated infections in the United States. Current prevention strategies are limited by their failure to account for patients who carry C. difficile asymptomatically, who may act as hidden reservoirs transmitting infections to other patients. To improve the understanding of asymptomatic carriers' contribution to C. difficile spread, we conducted admission and daily longitudinal culture-based screening for C. difficile in a US-based intensive care unit over nine months and performed whole-genome sequencing on all recovered isolates. Despite a high burden of carriage, with 9.3% of admissions having toxigenic C. difficile detected in at least one sample, only 1% of patients culturing negative on admission to the unit acquired C. difficile via cross-transmission. While patients who carried toxigenic C. difficile on admission posed minimal risk to others, they themselves had a 24-times greater risk for developing a healthcare-onset C. difficile infection than noncarriers. Together, these findings suggest that current infection prevention practices can be effective in preventing nosocomial cross-transmission of C. difficile, and that decreasing C. difficile infections in hospitals further will require interventions targeting the transition from asymptomatic carriage to infection.

Key patient demographics shape innate immune topography in noncritical hypoxic COVID-19 pneumonia

Risk of severe disease and death due to COVID-19 is increased in certain patient demographic groups, including those of advanced age, male sex, and obese body mass index. Investigations of the biological variations that contribute to this risk have been hampered by heterogeneous severity, with immunologic features of critical disease potentially obscuring differences between risk groups. To examine immune heterogeneity related to demographic risk factors, we enrolled 38 patients hospitalized with clinically homogeneous COVID-19 pneumonia - defined as oxygen saturation less than 94% on room air without respiratory failure, septic shock, or multiple organ dysfunction - and performed single-cell RNA-Seq of leukocytes collected at admission. Examination of individual risk factors identified strong shifts within neutrophil and monocyte/dendritic cell (Mo/DC) compartments, revealing altered immune cell type-specific responses in higher risk COVID-19 patient subgroups. Specifically, we found transcriptional evidence of altered neutrophil maturation in aged versus young patients and enhanced cytokine responses in Mo/DCs of male versus female patients. Such innate immune cell alterations may contribute to outcome differences linked to these risk factors. They also highlight the importance of diverse patient cohorts in studies of therapies targeting the immune response in COVID-19.

Effects of procalcitonin on antimicrobial treatment decisions in patients with coronavirus disease 2019 (COVID-19)

OBJECTIVE

To describe the natural course of procalcitonin (PCT) in patients with coronavirus disease 2019 (COVID-19) and the correlation between PCT and antimicrobial prescribing to provide insight into best practices for PCT data utilization in antimicrobial stewardship in this population.

DESIGN

Single-center, retrospective, observational study.

SETTING

Michigan Medicine.

PATIENTS

Inpatients aged ≥18 years hospitalized March 1, 2020, through October 31, 2021, who were positive for severe acute respiratory coronavirus virus 2 (SARS-CoV-2), with ≥1 PCT measurement. Exclusion criteria included antibiotics for nonpulmonary bacterial infection on admission, treatment with azithromycin only for chronic obstructive pulmonary disease (COPD) exacerbation, and pre-existing diagnosis of cystic fibrosis with positive respiratory cultures.

METHODS

A structured query was used to extract data. For patients started on antibiotics, bacterial pneumonia (bPNA) was determined through chart review. Multivariable models were used to assess associations of PCT level and bPNA with antimicrobial use.

RESULTS

Of 793 patients, 224 (28.2%) were initiated on antibiotics: 33 (14.7%) had proven or probable bPNA, 125 (55.8%) had possible bPNA, and 66 (29.5%) had no bPNA. Patients had a mean of 4.1 (SD, ±5.2) PCT measurements if receiving antibiotics versus a mean of 2.0 (SD, ±2.6) if not. Initial PCT level was highest for those with proven/probable bPNA and was associated with antibiotic initiation (odds ratio 95% confidence interval [CI], 1.17-1.30). Initial PCT (rate ratio [RR] 95% CI, 1.01-1.08), change in PCT over time (RR 95% CI, 1.01-1.05), and bPNA group (RR 95% CI, 1.23-1.84) were associated with antibiotic duration.

CONCLUSIONS

PCT trends are associated with the decision to initiate antibiotics and duration of treatment, independent of bPNA status and comorbidities. Prospective studies are needed to determine whether PCT level can be used to safely make decisions regarding antibiotic treatment for COVID-19.

Assessment of parental acceptance towards different non-pharmacological behaviour management techniques in pediatric dental care-a cross-sectional study

It is imperative to manage children with empathy and concern for their well-being in order to carry out any dental procedure smoothly. Owing to the inherent fear of dental operatory, behaviour management of children is an important aspect of pediatric dental care. Many techniques are available to help manage the behaviour of children. It is, however important to educate parents about these techniques and to get their cooperation for these techniques to be used on their children.This study aimed to familiarize the parents with non-pharmacological behavior management techniques and to determine the parental acceptance of such techniques in children seeking dental treatment in specialty care dental units. A total of 303 parents were evaluated through online questionnaires in this research. They were shown videos of randomly selected non-pharmacologic behaviour management techniques including tell-show-do, positive reinforcement, modelling and voice control. Parents were asked to watch the videos and give their response on seven-items inquiring about their acceptance levels regarding the respective techniques. The responses were recorded on a Likert scales ranging from strongly disagree to strongly agree. According to parental acceptance score (PAS), positive reinforcement was the most accepted technique whereas voice control was the least acceptable technique. Majority of the parents were more receptive towards those techniques that involved a healthy and friendly communication between a dentist and the pediatric patient such as, positive reinforcement, tell show do and modelling. Most significantly the people having low socio-economic status (SES) in Pakistan were more acceptable of voice control than people with high SES.

Prospective evaluation of data-driven models to predict daily risk of Clostridioides difficile infection at 2 large academic health centers

Many data-driven patient risk stratification models have not been evaluated prospectively. We performed and compared the prospective and retrospective evaluations of 2 Clostridioides difficile infection (CDI) risk-prediction models at 2 large academic health centers, and we discuss the models' robustness to data-set shifts.

Impact of cytotoxic chemotherapy on aldo-keto reductase family 1 member B10 expression

OBJECTIVE

Aldo-keto reductase family 1 member B10 (AKR1B10) is a protein that is produced and secreted by a significant number of breast cancers. However, a potential confounder to the use of AKR1B10 as a tumor marker is its elevation in patients given cytotoxic chemotherapy. We therefore conducted a prospective study to analyze AKR1B10 levels in patients with breast cancer receiving neoadjuvant cytotoxic chemotherapy.

METHODS

The study enrolled 10 patients from November 2015 to July 2017. All patients had locally advanced, but non-metastatic, breast cancer, and they received neoadjuvant chemotherapy followed by surgery. Serum AKR1B10 levels and tumor imaging were assessed before, during, and after chemotherapy.

RESULTS

No increase in serum AKR1B10 levels was noted in patients receiving chemotherapy whose levels were elevated at diagnosis.

CONCLUSION

The findings are complex, but the overall data suggest that AKR1B10 is suitable as a tumor marker in patients with elevated levels at the time of diagnosis.

The Fecal Microbiome in Quiescent Crohn's Disease with Persistent Gastrointestinal Symptoms Show Enrichment of Oral Microbes But Depletion of Butyrate and Indole Producers

Background and Aims

Even in the absence of inflammation, persistent symptoms in Crohn's disease (CD) are prevalent and negatively impact quality of life. We aimed to determine whether quiescent CD patients with persistent symptoms ( qCD+symptoms ) have changes in microbial structure and functional potential compared to those without symptoms ( qCD-symptoms ).

Methods

We performed a prospective multi-center observational study nested within the SPARC IBD study. CD patients were included if they had evidence of quiescent disease as defined by fecal calprotectin level < 150 mcg/g. Persistent symptoms were defined by the CD-PRO2 questionnaire. Active CD ( aCD ), diarrhea-predominant irritable bowel syndrome ( IBS-D ), and healthy controls ( HC ) were included as controls. Stool samples underwent whole genome shotgun metagenomic sequencing.

Results

A total of 424 patients were analyzed, including 39 qCD+symptoms, 274 qCD-symptoms, 21 aCD, 40 IBS-D, and 50 HC. Patients with qCD+symptoms had a less diverse microbiome, including significant reductions in Shannon diversity ( P <.001) and significant differences in microbial community structure ( P <.0001), compared with qCD-symptoms, IBS-D, and HC. Further, patients with qCD+symptoms showed significant enrichment of bacterial species that are normal inhabitants of the oral microbiome, including Klebsiella pneumoniae (q=.003) as well as depletion of important butyrate and indole producers, such as Eubacterium rectale (q=.001), Lachnospiraceae spp . (q<.0001), and Faecalibacterium prausnitzii (q<.0001), compared with qCD-symptoms. Finally, qCD+symptoms showed significant reductions in bacterial tnaA genes, which mediate tryptophan metabolism, as well as significant tnaA allelic variation, compared with qCD-symptoms.

Conclusion

The microbiome in patients with qCD+symptoms show significant changes in diversity, community profile, and composition compared with qCD-symptoms. Future studies will focus on the functional significance of these changes.

What You Need to Know

Background: Persistent symptoms in quiescent Crohn's disease (CD) are prevalent and lead to worse outcomes. While changes in the microbial community have been implicated, the mechanisms by which altered microbiota may lead to qCD+symptoms remain unclear.Findings: Quiescent CD patients with persistent symptoms demonstrated significant differences in microbial diversity and composition compared to those without persistent symptoms. Specifically, quiescent CD patients with persistent symptoms were enriched in bacterial species that are normal inhabitants of the oral microbiome but depleted in important butyrate and indole producers compared to those without persistent symptoms.Implications for Patient Care: Alterations in the gut microbiome may be a potential mediator of persistent symptoms in quiescent CD. Future studies will determine whether targeting these microbial changes may improve symptoms in quiescent CD.

Oral Health-Related Quality of Life in Breast Cancer Patients in the Northern Region of Saudi Arabia

BACKGROUND

Breast cancer is one of the most prevalent diseases, and ignoring dental health care before and after treatment can have severe long-term consequences. Additionally, this may have a negative impact on the patient's general quality of life.

AIM

The aim of the present study was to assess oral health-related quality of life (OHRQoL) among breast cancer patients and identify possible factors associated with the outcome.

METHODOLOGY

In this observational cross-sectional study, 200 women who had received breast cancer therapy and were being followed up at a hospital made up the sample. The study was conducted between January 2021 and July 2022. Information on sociodemographic characteristics, general health, and breast cancer was recorded. The decayed, missing, and filled teeth index was used in clinical examinations to identify caries experience. OHRQoL was evaluated using the Oral Health Impact Profile (OHIP-14) questionnaire. After adjusting for confounding variables, a logistic regression analysis was used to determine the related factors.

RESULTS

The mean OHIP-14 score was 11.48 (SD 1.35). There was a 63.0% prevalence of negative impacts. Age and the time frame from cancer diagnosis were found to be significantly linked with the outcome by binary logistic regression analysis.

CONCLUSIONS

Breast cancer survivors who were ≤55 years old and the time elapsed since diagnosis was less than 36 months had a poor OHRQoL. To lessen the negative impacts of cancer treatment and enhance quality of life, patients with breast cancer need special oral care and should be monitored before, during, and after cancer treatment.

Gut community structure as a risk factor for infection in Klebsiella -colonized patients

The primary risk factor for infection with members of the Klebsiella pneumoniae species complex is prior gut colonization, and infection is often caused by the colonizing strain. Despite the importance of the gut as a reservoir for infectious Klebsiella , little is known about the association between the gut microbiome and infection. To explore this relationship, we undertook a case-control study comparing the gut community structure of Klebsiella -colonized intensive care and hematology/oncology patients. Cases were Klebsiella -colonized patients infected by their colonizing strain (N = 83). Controls were Klebsiella -colonized patients that remained asymptomatic (N = 149). First, we characterized the gut community structure of Klebsiella -colonized patients agnostic to case status. Next, we determined that gut community data is useful for classifying cases and controls using machine learning models and that the gut community structure differed between cases and controls. Klebsiella relative abundance, a known risk factor for infection, had the greatest feature importance but other gut microbes were also informative. Finally, we show that integration of gut community structure with bacterial genotype or clinical variable data enhanced the ability of machine learning models to discriminate cases and controls. This study demonstrates that including gut community data with patient- and Klebsiella -derived biomarkers improves our ability to predict infection in Klebsiella -colonized patients.

Importance

Colonization is generally the first step in pathogenesis for bacteria with pathogenic potential. This step provides a unique window for intervention since a given potential pathogen has yet to cause damage to its host. Moreover, intervention during the colonization stage may help alleviate the burden of therapy failure as antimicrobial resistance rises. Yet, to understand the therapeutic potential of interventions that target colonization, we must first understand the biology of colonization and if biomarkers at the colonization stage can be used to stratify infection risk. The bacterial genus Klebsiella includes many species with varying degrees of pathogenic potential. Members of the K. pneumoniae species complex have the highest pathogenic potential. Patients colonized in their gut by these bacteria are at higher risk of subsequent infection with their colonizing strain. However, we do not understand if other members of the gut microbiota can be used as a biomarker to predict infection risk. In this study, we show that the gut microbiota differs between colonized patients that develop an infection versus those that do not. Additionally, we show that integrating gut microbiota data with patient and bacterial factors improves the ability to predict infections. As we continue to explore colonization as an intervention point to prevent infections in individuals colonized by potential pathogens, we must develop effective means for predicting and stratifying infection risk.

Abstract 2591: Role of Rab25 in Melanoma and its potential targeting

Background: RAB25 is a protein that belongs to the RAB11 subfamily located in the lq22 locus of chromosome and is ubiquitously expressed in cells of the gastrointestinal mucosa, ileum, and kidney. Its role in tumorigenesis is variable but is unclear in the case of melanoma progression. Our previous studies showed that loss of RAB25 has a special role in mediating the tumorigenic transformation of human mammary epithelial cells. Its loss particularly cooperated with mutant Ras isoforms to promote transformation in vitro. We are now examining the role of RAB25 in melanomas as melanomas exhibit a high rate of N-Ras mutations. We hypothesize that the presence of NRAS types of mutation and expression of RAB25 are mutually exclusive as RAB25 functions are a tumor suppressor to inhibit this mutation. Methods: Different NRAS mutant melanoma cell lines (SKMEL-2, SKMEL-28, WM1366 and WM266-4) were examined forRab25 expression through qRT-PCR and Western Blotting. The positive control was MCF cell lines and MDA-MB-231 was considered as negative control. Immunohistochemistry was done with biopsy proven melanoma tissue samples and normal adjacent tissue to observe the trend of Rab25 expression. Keratinocytes and fibroblasts in the tissue samples were considered as internal controls.Results: We found a significant decrease in Rab25 expression in NRAS mutant melanoma cell lines compared to Raf mutants and primary melanocytes. The reduction was prominent at both the RNA and protein level. RAB25 expression was also reduced in melanoma tumors as compared to surrounding tissue. Conclusion: RAB25 loss may indeed cooperate with NRAS mutation to promote transformation in melanomas. Further studies including overexpression experiment in the cell line model followed by migration assay, invasion assay, and in vivo nude mouse experiments will provide further confirmation of our hypothesis.

Citation Format: Samikshya Kandel, Krishna Rao. Role of Rab25 in Melanoma and its potential targeting [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2591.

Contrasting effect of ficoll on apo and holo forms of bacterial chemotaxis protein Y: Selective destabilization of the conformationally altered holo form

Chemotaxis Y (CheY), upon metal binding, displays a drastic alteration in its structure and stability. This premise prompted us to study the effect of crowding on the two conformationally distinct states of the same test protein. A comparative analysis on the structure and thermal stability in the presence and absence of the macromolecular crowder, ficoll, and its monomeric unit, sucrose, revealed a contrasting effect of ficoll on the apo and holo forms. In the presence of ficoll while the thermal stability (T_m) of the apo form is enhanced, the thermal stability of the holo form is reduced. The selective lowering of T_m for the holo form in the combined presence of ficoll and sucrose and not in sucrose alone suggests that the contrasting effect is due to the macromolecular nature of ficoll. Since metal-protein interaction remains unperturbed in the presence of ficoll and Mg²⁺ sequestration is ruled out in a systematic manner the alternative possibility for the exclusive reduction in the thermal stability of the holo form is the ficoll-induced modulation of the relative population of apo and holo forms of CheY.

Exploring an Association between Body Mass Index and Oral Health-A Scoping Review

BACKGROUND

Basal metabolic index (BMI) is a unique anthropometric indicator used to define the relative amount of body fat on an individual's frame. There are many diseases and conditions associated with obesity and underweight. Recent research trials suggest that there is a significant association between oral health indicators and BMI as both are attributed to common risk factors such as dietary, genetic, socioeconomic, and lifestyle issues.

OBJECTIVES

The main objective of this review paper is to emphasize the association between BMI and oral health with available literature evidence.

METHODOLOGY

A literature search was conducted using multiple databases comprising of MEDLINE (via PubMed), EMBASE, and Web of Science. The terms used for the search were "body mass index", "periodontitis", "dental caries", and "tooth loss".

RESULTS

In total, 2839 articles were obtained from the analysis of the databases. Unrelated articles from the available full text of 1135 articles were excluded. The main reasons for excluding the articles were: they were dietary guidelines and policy statements. A total of 66 studies were finally included in the review.

CONCLUSION

The presence of dental caries, periodontitis and tooth loss may be associated with a higher BMI or obesity, whereas, improved oral health might be associated with lower BMI. Promoting general and oral health should be a hand in hand feature, as common risk factors can be embattled.

A Predictive Model to Identify Complicated Clostridiodes difficile Infection

Background

Clostridioides difficile infection (CDI) is a leading cause of health care-associated infection and may result in organ dysfunction, colectomy, and death. Published risk scores to predict severe complications from CDI demonstrate poor performance upon external validation. We hypothesized that building and validating a model using geographically and temporally distinct cohorts would more accurately predict risk for complications from CDI.

Methods

We conducted a multicenter retrospective cohort study of adults diagnosed with CDI. After randomly partitioning the data into training and validation sets, we developed and compared 3 machine learning algorithms (lasso regression, random forest, stacked ensemble) with 10-fold cross-validation to predict disease-related complications (intensive care unit admission, colectomy, or death attributable to CDI) within 30 days of diagnosis. Model performance was assessed using the area under the receiver operating curve (AUC).

Results

A total of 3646 patients with CDI were included, of whom 217 (6%) had complications. All 3 models performed well (AUC, 0.88-0.89). Variables of importance were similar across models, including albumin, bicarbonate, change in creatinine, non-CDI-related intensive care unit admission, and concomitant non-CDI antibiotics. Sensitivity analyses indicated that model performance was robust even when varying derivation cohort inclusion and CDI testing approach. However, race was an important modifier, with models showing worse performance in non-White patients.

Conclusions

Using a large heterogeneous population of patients, we developed and validated a prediction model that estimates risk for complications from CDI with good accuracy. Future studies should aim to reduce the disparity in model accuracy between White and non-White patients and to improve performance overall.

274. Epidemiology and Antimicrobial Treatment Impact of Procalcitonin in Patients with COVID-19

Background

Procalcitonin (PCT) is often measured in patients with signs of bacterial infection. PCT is often elevated in bacterial pneumonia and septic shock and usually low in viral infections. Recent studies have found a correlation between PCT and disease severity in COVID-19, and most patients receive antibiotics despite bacterial co-infection being rare. We sought to characterize PCT trends in COVID-19, assess its relation to bacterial pneumonia, and assess its relation to clinical decision making around antimicrobial use.

Methods

We included patients ≥18 hospitalized at Michigan Medicine (3/1/20–10/31/21), positive for COVID-19, with ≥ 1 PCT measurement. Structured query was used to retrospectively extract data. Patients started on an antibiotic underwent retrospective chart review by 2 reviewers for presence of bacterial pneumonia (bPNA), and were classified as having proven, probable, possible, or no bPNA (Figure 1). Multivariable models controlling for time from start of the pandemic, demographics, and comorbidities were used to determine associations of PCT and bPNA with antimicrobial use. Figure 1:Flow diagram of patients included in analyses

Results

793 patients met inclusion criteria, with 224 (28.2%) initiated on antibiotics. Of these 224, 33 (14.7%) had proven/probable bPNA, 125 (55.8%) had possible bPNA, and 66 (29.5%) had no bPNA. On average, patients had 2.6 ±3.7 (mean ±SD) PCT measurements, with 4.1 ±5.2 if on antibiotics vs. 2.0 ±2.6 if not. Initial PCT was higher in those on antibiotics and highest in those with proven/probable bPNA (Table 1). After adjustment for confounders, initial PCT was associated with antibiotic initiation (OR 1.68, 95% CI 1.47-1.91, p &lt; 0.0001) (Table 2). Initial PCT (RR 1.11, 95% CI 1.03-1.20, p=0.008), change in PCT over time (RR 1.03, 95% CI 1.01-1.05, p=0.007), and bPNA category (RR 1.51, 95% CI 1.23-1.84, p &lt; 0.0001) were associated with antibiotic duration (Table 3). Table 1:Number of PCT measures by antibiotic and bPNA statusTable 2:Multivariable logistic regression model results for covariate associations with antibiotic initiation (n=793)Table 3:Multivariable negative binomial model results for covariate associations with antibiotic duration (n=224)

Conclusion

PCT was elevated in patients with COVID-19, but more pronounced with bPNA. Antibiotics were started in &gt; 25% of patients, regardless of bPNA. PCT trends associate with the decision to initiate antibiotics and treatment duration, independent of bPNA and comorbidities. Future prospective studies should determine if PCT can be used to safely make decisions around antibiotic treatment for bacterial infection during COVID-19.

Disclosures

Krishna Rao, MD, MS, Merck & Co., Inc.: Grant/Research Support|Seres Therapeutics: Advisor/Consultant|Summit Therapeutics: Advisor/Consultant.

District-level religious composition and child health in India

Background

Community characteristics are a significant social determinant of child health. Little is known about the effects of social heterogeneity as a specific factor that might impact health. This paper aims to fill the void in research on the health effects of India’s district-level religious heterogeneity.

Methods

Weighted state fixed effects multivariate logistic regression was applied to India’s Third District Level Household Survey (2007–2008). The dependent variables were death of a child under five and indicators of healthcare utilization. The key independent variables were the proportions in the district who were Hindu, Muslim, Christian, Buddhist, and Sikh. The analysis controlled for generic community diversity, household religion, and socioeconomic status. Separate, sub-group analysis focused on Muslims only, Christians only, and Buddhists only.

Results

Multivariate fixed effects models show that a 1% point increase in the proportion of Muslim, Christian, or Buddhist households in a community is associated with respective odds ratios of child death of 1.008, 1.009, and 1.012 of experiencing the death of a child. The impact of a household’s own religious affiliation is statistically insignificant in these models. Higher proportions of Muslims and Christians in a community lower the odds of BCG (a vaccine for childhood tuberculosis) receipt and child healthcare-seeking.

Conclusions

Households residing where there are higher levels of religious minorities in India experience worse child survival. These effects are not mediated by the household’s own religious affiliation. There is evidence that health system performance and quality is systematically worse in communities with higher proportions of religious minorities. Our study can help policymakers identify communities where children may be at higher risk based on community heterogeneity and the potential for insufficient collective action. Policymakers might consider flagging these communities for special attention, because social heterogeneity is likely to be of long duration.

Duodenal Permeability Is Associated With Mucosal Microbiota in Compensated Cirrhosis

INTRODUCTION

Several complications of decompensated cirrhosis are believed to result from increased intestinal permeability. However, little is known about the relationship between mucosal bacteria and epithelial permeability in cirrhosis. We aimed to assess epithelial permeability and associations with mucosal bacteria in patients with compensated cirrhosis.

METHODS

We obtained duodenal tissue biopsies from patients with compensated cirrhosis and controls. Patients were excluded if they used antibiotics or immunosuppression. The composition of mucosal microbiota was determined by 16S rRNA gene sequencing and epithelial permeability by transepithelial electrical resistance (TEER) and tight junction protein expression.

RESULTS

We studied 24 patients with compensated cirrhosis and 20 controls. Patients with cirrhosis were older than controls (62 vs 52 years, P = 0.02) but had a similar number of extrahepatic comorbidities (2.2 vs 1.4, P = 0.13). Patients with compensated cirrhosis had lower duodenal TEER (i.e., increased epithelial permeability; 13.3 Ω/cm 2 ± 3.4 vs 18.9 Ω/cm 2 ± 7.1; P = 0.004). Patients with compensated cirrhosis trended toward a distinct mucosal microbiota community structure relative to controls ( P = 0.09). Clustering analysis identified two unique enterotypes. These enterotypes differed in bacterial composition and also TEER. A beta-binomial model found 13 individual bacteria associated with TEER, including Lactobacillus and Bifidobacterium taxa. Thirty-six taxa were associated with tight junction protein expression, including Lactobacillus and Bifidobacterium.

DISCUSSION

Compensated cirrhosis is characterized by increased duodenal epithelial permeability with a distinct mucosal microbial community. Intriguingly, bacteria previously associated with health were protective of duodenal permeability.

Proton Pump Inhibitor-Induced Gut Dysbiosis Increases Mortality Rates for Patients with Clostridioides difficile Infection

Clostridioides difficile infection (CDI) is associated with high mortality rates among patients with chronic illnesses. We aimed to identify avoidable risk factors to reduce the mortality rate in CDI patients. A total of 306 patients with diarrhea and clinical suspicion of CDI were enrolled, and fecal samples were gathered from 145 patients. CDI was diagnosed by fecal positivity for the C. difficile tcdB gene. Risk factors associated with death within 180 days were identified using Cox regression analysis. The fecal microbiota was determined through bacterial 16S rRNA gene sequencing. Of the patients with diarrhea, 240 (mean age, 69.1 years) were positive for CDI, and 91 died within 180 days. Multivariate analysis revealed that male sex, high Charlson Comorbidity Index and McCabe scores, high serum C-reactive protein levels, low hematocrit levels, low absolute eosinophil counts, high neutrophil/lymphocyte ratios, and daily use of proton pump inhibitors (PPIs) were independent risk factors for overall mortality. Cumulative analyses confirmed the association of duration-dependent PPI use with a high mortality rate. Fecal microbiota analyses showed associations of decreased relative abundance of Ruminococcus gnavus (P = 0.001) and Prevotella copri (P = 0.025) and increased relative abundance of Parabacteroides merdae (P = 0.001) and Clostridioides difficile (P = 0.040) with higher mortality rates in patients with CDI. Moreover, these microbiota changes were correlated with the duration of PPI use. IMPORTANCE This article demonstrates that daily PPI use was the only avoidable risk factor for death. With more extended PPI use, the mortality rate was higher in patients with CDI. Decreases in Prevotella copri and Ruminococcus gnavus and increases in Parabacteroides merdae and Clostridioides difficile in line with daily PPI use duration were significantly associated with the death of CDI patients. Our findings provide in-depth insights into the cautious use of PPIs in chronically ill patients with CDI.

Clostridioides difficile toxin is infrequently detected in inflammatory bowel disease and does not associate with clinical outcomes

INTRODUCTION

Clostridioides difficile infection (CDI) rates and outcomes can vary based on differences in testing strategy. Our aim was to assess the prevalence of toxin detection in inflammatory bowel disease (IBD) when compared to those without IBD. Secondly, the clinical outcomes of CDI in IBD were assessed using two-step testing strategies.

METHODS

We included patients undergoing CDI testing from four academic centers in the United States between January 1, 2018 and June 30, 2020. First the prevalence of toxin detection was compared between individuals with IBD and those without IBD. Secondly, among patients with IBD a primary composite outcome of abdominal colectomy, admission to an intensive care unit (ICU) or death within 30 days of C. difficile testing was assessed across the three categorical groups (screen positive/toxin positive, screen positive/toxin negative and screen negative assay) resulting from the two-step testing strategy.

RESULTS

When comparing individuals with a positive screening assay, patients with IBD were less likely to have toxin detected by enzyme immunoassay (EIA) as compared to the non-IBD population (22/145 (15.2%) vs. 413/1144 (36.1%), p < 0.0001). Among all patients with IBD (n = 300), twenty-five (8.3%) had a screen positive assay/toxin positive assay, 136 (45.3%) had a screen positive/toxin negative assay and 139 (46.3%) had a negative screening assay. No significant difference in the primary composite outcome was detected across the three groups (p = 0.566).

CONCLUSION

When compared to those without IBD, patients with IBD have a reduced proportion of cases of C. difficile with toxin positivity. Differences in clinical outcomes among patients with IBD were not detected and limited by the infrequent detection of expressed toxin.

Combined comparative genomics and clinical modeling reveals plasmid-encoded genes are independently associated with Klebsiella infection

Members of the Klebsiella pneumoniae species complex frequently colonize the gut and colonization is associated with subsequent infection. To identify genes associated with progression from colonization to infection, we undertook a case-control comparative genomics study. Concordant cases (N = 85), where colonizing and invasive isolates were identical strain types, were matched to asymptomatically colonizing controls (N = 160). Thirty-seven genes are associated with infection, 27 of which remain significant following adjustment for patient variables and bacterial phylogeny. Infection-associated genes are not previously characterized virulence factors, but instead a diverse group of stress resistance, regulatory and antibiotic resistance genes, despite careful adjustment for antibiotic exposure. Many genes are plasmid borne, and for some, the relationship with infection is mediated by gut dominance. Five genes were validated in a geographically-independent cohort of colonized patients. This study identifies several genes reproducibly associated with progression to infection in patients colonized by diverse Klebsiella.

Phase I/II clinical trial of temsirolimus and lenalidomide in patients with relapsed and refractory lymphomas

The PI3K/Akt/mTOR (PAM) axis is constitutively activated in multiple lymphoma subtypes and is a promising therapeutic target. The mTOR inhibitor temsirolimus (TEM) and the immunomodulatory agent lenalidomide (LEN) have overlapping effects within the PAM axis with synergistic potential. This multicenter phase I/II study evaluated combination therapy with TEM/LEN in patients with relapsed and refractory lymphomas. Primary endpoints of the phase II study were rates of complete (CR) and overall response (ORR). There were 18 patients in the phase I dose-finding study, and TEM 25 mg weekly and LEN 20 mg on day 1 through day 21 every 28 days was established as the recommended phase II dose. An additional 93 patients were enrolled in the phase II component with three cohorts: diffuse large B-cell lymphoma (DLBCL, n=39), follicular lymphoma (FL, n=15), and an exploratory cohort of other lymphoma histologies with classical Hodgkin lymphoma (cHL) comprising the majority (n=39 total, n=20 with cHL). Patients were heavily pretreated with a median of four (range, 1-14) prior therapies and one-third with relapse following autologous stem cell transplantation (ASCT); patients with cHL had a median of six prior therapies. The FL cohort was closed prematurely due to slow accrual. ORR were 26% (13% CR) and 64% (18% CR) for the DLBCL and exploratory cohorts, respectively. ORR for cHL patients in the exploratory cohort, most of whom had relapsed after both brentuximab vedotin and ASCT, was 80% (35% CR). Eight cHL patients (40%) proceeded to allogeneic transplantation after TEM/LEN therapy. Grade ≥3 hematologic adverse events (AE) were common. Three grade 5 AE occurred. Combination therapy with TEM/LEN was feasible and demonstrated encouraging activity in heavily-pretreated lymphomas, particularly in relapsed/refractory cHL (clinicaltrials gov. Identifier: NCT01076543).

AKR1B10 as a Potential Novel Serum Biomarker for Breast Cancer: A Pilot Study

Background

Aldo-keto reductase 1B10 (AKR1B10) is a secretory protein that is upregulated in breast cancer.

Objective

This case-controlled pilot study evaluated the serum level of AKR1B10 in healthy women and patients with a localized or metastatic breast cancer.

Methods

AKR1B10 levels were measured by ELISA and IHC in several patient cohorts.

Results

Our data showed that serum AKR1B10 was significantly elevated in patients with localized (6.72 ± 0.92 ng/ml) or metastatic (7.79 ± 1.13 ng/ml) disease compared to cancer-free healthy women (1.69 ± 0.17 ng/ml) (p<0.001); the serum AKR1B10 was correlated with its expression in tumor tissues, but not with the tumor burden, molecular subtypes or histological stages. After surgical removal of primary tumors, the serum AKR1B10 was rapidly decreased within 3 days and plateaued at a level similar to that of healthy controls in most patients. ROC curve analysis suggested the optimal diagnostic cut-off value of serum AKR1B10 at 3.456 ng/ml with AUC 0.9045 ± 0.0337 (95% CI 0.8384 - 0.9706), sensitivity 84.75% (95% CI 73.01% to 92.78%), and specificity 93.88% (95% CI 83.13% to 98.72%).

Conclusions

These data indicate the potential value of serum AKR1B10 as a biomarker of breast cancer.

Baseline Predictors of Longitudinal Changes in Symptom Severity and Quality of Life in Patients With Suspected Gastroparesis

BACKGROUND & AIMS

Whether gastric emptying tests predict longitudinal outcomes in patients with symptoms of gastroparesis is unclear. We aimed to determine whether baseline gastric emptying tests and gut motility parameters could impact longitudinal symptom(s) and quality of life (QOL) in a prospective, observational cohort study of patients with symptoms of gastroparesis.

METHODS

One hundred fifty patients with gastroparesis symptoms underwent simultaneous scintigraphy (GES) and wireless motility capsule (WMC) measurement of gastric emptying and other motility parameters. Patient Assessment of Upper Gastrointestinal Symptoms and Quality of Life were administered at baseline, and 3 and 6 months after testing. Multivariable generalized linear marginal models were fit to determine which baseline parameters predict longitudinal changes in symptoms and QOL.

RESULTS

Overall upper GI symptoms and QOL scores were moderate in severity at baseline and significantly improved over 6 months. Clinical variables, including female gender, harder stools by Bristol stool form score, and presence of functional dyspepsia (FD) by Rome III criteria, were predictive of more severe upper GI symptoms. Even after controlling for these clinical factors, delayed gastric emptying by GES or WMC was associated with worse symptom severity and QOL scores. Low gastric and elevated small bowel contractile parameters by WMC were also independently associated with more severe upper GI symptoms and worse QOL scores.

CONCLUSIONS

Baseline features, including demographic and clinical variables, delayed gastric emptying and abnormal gastrointestinal contractility, were independent predictors of more severe longitudinal symptoms and worse quality of life outcomes. These factors may help to risk stratify patients and guide treatment decisions. ClinicalTrials.gov no: NCT02022826.

Abstract P4-02-16: Investigating the role of NRIP1 as a novel marker and therapeutic target for breast cancer

Background:. Tamoxifen and fulvestrant target estrogen receptor (ER), which is overexpressed in more than 80% of breast cancer (BC) cases, and have significantly improved the survival rate. However, in most metastatic cases, resistance is inevitable. Identifying gene targets for improving the efficiency of hormone therapy, delaying the progress of resistance development, and restoring the efficacy of hormone therapy has great significance. Epidemiological studies of human populations found that early age at menarche significantly associates with the risk of BC. Remarkably, a five-year delay in menarche has been shown to correspond to a 35% reduction of BC. This suggests that identifying genes that regulate female sexual maturation (FSM) might provide a novel approach for exploring the genetic and molecular mechanisms of BC, providing clues in the search for new therapeutic targets. We previously identified and verified that nuclear receptor interacting protein 1 (Nrip1, also named Rip140) is a regulator of female sexual maturation. NRIP1, a co-regulator of nuclear receptors, interacts with several known signaling pathways for BC, such as E2F and estrogen receptor (ER). Human genome-wide association studies suggested that polymorphisms of NRIP1 are significantly associated with the risk of BC. Furthermore, elevating NRIP1 can promote epithelial cells proliferation and increase the development rate and size of the mammary gland, while depleting NRIP1 expression has the opposite effect. Importantly, clinical studies suggested that breast cancer patients with higher level of NRIP1 have a relatively poorer prognosis. Experiments and results:. 1. To investigate the role of NRIP1 in BC, we first measured NRIP1 expression in cancers. We found that NRIP1 was overexpressed in the tissues of BC and the BC cell lines. Importantly, immunohistochemistry assay showed that that NRIP1 is elevated in BC cell lines and tissues from patients with BC. Interestingly, overexpressed NRIP1 accumulated in the cytoplasm of the stromal cells in the benign tumors; but, in the malignant tumors, there was more accumulation in the nuclei of epithelia. Further studies revealed that suppressing NRIP1 could increase apoptosis of cancer cells in vitro and suppress the initiation and growth of DMBA (7,12-Dimethylbenz(a)anthracene) induced breast tumors. 2. Our previous studies have shown that deletion of NRIP1, in a variety of cell types, could suppress the activity of NFκB, which promotes the development of hormone therapy resistance; therefore, indicating that the suppression of NRIP1 may also suppress hormone therapy resistance. To test this hypothesis, we induced tamoxifen resistance in MCF7, which is estrogen receptor positive. During the induction, we found that NRIP1 expression increased gradually with the development of tamoxifen resistance. Interestingly, along with the upregulation of NRIP1 expression, we found that NRIP1 was translocated from the cytosol into the nucleus. These results suggest that not only the level of NRIP1 expression, but also the location, are related to the development of tamoxifen resistant. Furthermore, we found that suppressing the expression of NRIP1 by siRNA in tamoxifen resistant MCF7 (MCF7-TR) could significantly reduce the percentage of cells in the S phase and increase apoptosis with or without tamoxifen treatment. Conclusion:. 1. Investigating the genetic regulation of FSM may provide clues for identifying novel BC related genes. 2. NRIP1 plays an important role in BC. 3. Inhibiting NRIP1 may suppress the initiation and growth of BC. 4. NRIP1 overexpression and nuclear translocation are involved in the development of hormone therapy resistance. 5. The deletion of NRIP1 can suppress the development tamoxifen resistance in vitro.

Citation Format: Yun Zhu, Fawwad Zaidi, Krishna Rao, Rong Yuan. Investigating the role of NRIP1 as a novel marker and therapeutic target for breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P4-02-16.

Plant-water sensitivity regulates wildfire vulnerability

Extreme wildfires extensively impact human health and the environment. Increasing vapour pressure deficit (VPD) has led to a chronic increase in wildfire area in the western United States, yet some regions have been more affected than others. Here we show that for the same increase in VPD, burned area increases more in regions where vegetation moisture shows greater sensitivity to water limitation (plant-water sensitivity; R² = 0.71). This has led to rapid increases in human exposure to wildfire risk, both because the population living in areas with high plant-water sensitivity grew 50% faster during 1990–2010 than in other wildland–urban interfaces and because VPD has risen most rapidly in these vulnerable areas. As plant-water sensitivity is strongly linked to wildfire vulnerability, accounting for ecophysiological controls should improve wildfire forecasts. If recent trends in VPD and demographic shifts continue, human wildfire risk will probably continue to increase.

The authors show that an ecosystem’s sensitivity to drought, measured as the amount of change in vegetation moisture content for a given change in background moisture, predicts the fire hazard in that location.

Can prediction scores be used to identify patients at risk of Clostridioides difficile infection?

PURPOSE OF REVIEW

To describe the current state of literature on modeling risk of incident and recurrent Clostridioides difficile infection (iCDI and rCDI), to underscore limitations, and to propose a path forward for future research.

RECENT FINDINGS

There are many published risk factors and models for both iCDI and rCDI. The approaches include scores with a limited list of variables designed to be used at the bedside, but more recently have also included automated tools that take advantage of the entire electronic health record. Recent attempts to externally validate scores have met with mixed success.

SUMMARY

For iCDI, the performance largely hinges on the incidence, which even for hospitalized patients can be low (often <1%). Most scores fail to achieve high accuracy and/or are not externally validated. A challenge in predicting rCDI is the significant overlap with risk factors for iCDI, reducing the discriminatory ability of models. Automated electronic health record-based tools show promise but portability to other centers is challenging. Future studies should include external validation and consider biomarkers to augment performance.

An uncommon aetiology for a common clinical problem: Primary pericardial mesothelioma

Mesothelioma is a tumour arising from the mesothelial cells lining the pleura, pericardium, peritoneum, or the tunica vaginalis of testes. Primary pericardial mesothelioma is a rare tumour that can have varied manifestations and survival in patients with malignant pericardial tumours is generally dismal. The role of asbestos in pericardial mesotheliomas is less well established compared to that in pleural or peritoneal mesotheliomas. The prognosis is generally poor with the treatment options available. We present a middle-aged man with large pericardial effusion secondary to primary pericardial mesothelioma with no previous exposure to asbestos.

17. Comparative Assessment of a Machine Learning Model and Rectal Swab Surveillance to Predict Hospital Onset Clostridioides difficile

Background

Hospital onset Clostridioides difficile infection (HO-CDI) is associated with significant morbidity and mortality. Screening individuals at risk could help limit transmission, however swab-based surveillance for HO-CDI is resource intensive. Applied to electronic health records (EHR) data, machine learning (ML) models present an efficient approach to assess patient risk. We compare the effectiveness of swab surveillance against daily risk estimates produced by a ML model in detecting patients who will develop HO-CDI.

Methods

Patients presenting to Michigan Medicine’s ICUs and oncology wards between June 6th and October 8th 2020 had rectal swabs collected on admission, weekly, and at discharge from the unit, as part of VRE surveillance. We performed anaerobic culture on the residual media followed by a custom, multiplex PCR on isolates to identify toxigenic C. difficile. Risk of HO-CDI was calculated daily for each patient using a previously validated EHR-based ML model. Swab results and model risk scores were aggregated for each admission and assessed as predictors of HO-CDI. Holding sensitivity equal, we evaluated both approaches in terms of accuracy, specificity, and positive predictive value (PPV).

Results

Of 2,044 admissions representing 1,859 patients, 39 (1.9%) developed HO-CDI. 23.1% (95% CI: 11.1–37.8%) of HO-CDI cases had at least one positive swab. At this sensitivity, model performance was significantly better than random but worse compared to swab surveillance—accuracy: 87.5% (86.0–88.9%) vs. 94.3% (93.3–95.3%), specificity: 88.7% (87.3–90.0%) vs. 95.7% (94.8–96.6%), PPV: 3.8% (1.6–6.4%) vs. 9.4% (4.3–16.1%). Combining swab AND model yielded lower sensitivity 2.6% (0.0–8.9%) compared to combining swab OR model at 43.6% (27.3–60.0%), and yielded PPV 7.1% (0.0–25.0%) vs. 43.6% (27.3–60.0%) respectively (Figure 1).

Figure 1. Surveillance & risk score performance.

Conclusion

Compared to swab surveillance using a ML model for predicting HO-CDI results in more false positives. The ML model provides daily risk scores and can be deployed using different thresholds. Thus, it can inform varied prevention strategies for different risk categories, without the need for resource intensive swabbing. Additionally, the approaches may be complimentary as the patients with HO-CDI identified by each approach differ.

Disclosures

Vincent B. Young, MD, PhD, American Society for Microbiology (Other Financial or Material Support, Senior Editor for mSphere)Vedanta Biosciences (Consultant) Krishna Rao, MD, MS, Bio-K+ International, Inc. (Consultant)Merck & Co., Inc. (Grant/Research Support)Roche Molecular Systems, Inc. (Consultant)Seres Therapeutics (Consultant)

Accuracy and Clinical Utility of Reports from Outside Hospitals for CT of the Cervical Spine in Blunt Trauma

BACKGROUND AND PURPOSE

Multidetector CT is the workhorse for detecting blunt cervical spine injury. There is no standard of care for re-interpretation of radiology images for patients with blunt trauma transferred to a higher level of care. The clinical impact of discrepancies of cervical spine CT reads remains unclear. We evaluated the discordance between primary (from referring hospitals) and secondary radiology interpretations (from a receiving level I tertiary trauma center) of cervical spine CT scans in patients with blunt trauma and assessed the clinical implications of missed cervical spine fractures.

MATERIALS AND METHODS

Medical records of patients with blunt trauma transferred to our institution between 2008 and 2015 were reviewed. Primary and secondary interpretations were compared and categorized as concordant and discordant. Two senior neuroradiologists adjudicated discordant reports. The benefit of re-interpretation was determined. For discordant cases, outcomes at discharge, injury severity pattern, treatment, and arrival in a cervical collar were assessed.

RESULTS

Six hundred fifty patients were included; 608 (94%) presented with concordant reports: 401 (61.7%) with fractures and 207 (31.8%) with no fractures. There were 42 (6.5%) discordant reports; 18 (2.8%) were cervical spine injuries undetected on the primary interpretation. Following adjudication, the secondary interpretation improved the sensitivity (99.3% versus 95.7%) and specificity (99.1% versus 91.7%) in detecting cervical spine fractures compared with the primary interpretation alone (P < .001).

CONCLUSIONS

There was an overall 6.5% discordance rate between primary and secondary interpretations of cervical spine CT scans. The secondary interpretation of the cervical spine CT increased the sensitivity and specificity of detecting cervical spine fractures in patients with blunt trauma transferred to higher-level care.

MRI Patterns in Pediatric CNS Hemophagocytic Lymphohistiocytosis

BACKGROUND AND PURPOSE

Neuroimaging has an important role in detecting CNS involvement in children with systemic or CNS isolated hemophagocytic lymphohistiocytosis. We characterized a cohort of pediatric patients with CNS hemophagocytic lymphohistiocytosis focusing on neuroradiologic features and assessed whether distinct MR imaging patterns and genotype correlations can be recognized.

MATERIALS AND METHODS

We retrospectively enrolled consecutive pediatric patients diagnosed with hemophagocytic lymphohistiocytosis with CNS involvement treated at 2 pediatric neurology centers between 2010 and 2018. Clinical and MR imaging data were analyzed.

RESULTS

Fifty-seven children (40 primary, 70%) with a median age of 36 months (interquartile range, 5.5-80.8 months) were included. One hundred twenty-three MR imaging studies were assessed, and 2 broad imaging patterns were identified. Pattern 1 (significant parenchymal disease, 32/57, 56%) was seen in older children (P = .004) with worse clinical profiles. It had 3 onset subpatterns: multifocal white matter lesions (21/32, 66%), brainstem predominant disease (5, 15%), and cerebellitis (6, 19%). All patients with the brainstem pattern failed to meet the radiologic criteria for chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids. An attenuated imaging phenotype (pattern 2) was seen in 25 patients (44%, 30 studies) and was associated with younger age.

CONCLUSIONS

Distinct MR imaging patterns correlating with clinical phenotypes and possible genetic underpinnings were recognized in this cohort of pediatric CNS hemophagocytic lymphohistiocytosis. Disruptive mutations and missense mutations with absent protein expression correlate with a younger onset age. Children with brainstem and cerebellitis patterns and a negative etiologic work-up require directed assessment for CNS hemophagocytic lymphohistiocytosis.