An observational study demonstrates human-adapted Staphylococcus aureus strains have a higher frequency of antibiotic resistance compared to cattle-adapted strains isolated from dairy farms making farmstead cheese.

BACKGROUND: Staphylococcus aureus is a multi-host zoonotic pathogen causing human and livestock diseases. Dairy farms that make artisan cheese have distinctive concerns for S. aureus control. Antimicrobial-resistant (AMR) S. aureus is a public and animal health concern. There is a need to study the population structure of AMR S. aureus at the human-animal interface and understand the path of zoonotic transmission. This cross-sectional observational study aimed to assess the genetic diversity and AMR patterns of S. aureus isolated from cattle and humans on conventional and organic Vermont dairy farms that produce and sell farmstead cheese. RESULTS: A convenience sample of 19 dairy farms in Vermont was enrolled, and 160 S. aureus isolates were collected from cow quarter milk (CQM), bulk tank milk (BTM), human-hand and -nasal swabs. After deduplication, 89 isolates were used for the analysis. Sequence types (STs) were determined by multilocus sequence typing and cataloged to the PubMLST database. Nine defined and five novel STs were identified. For BTM and CQM samples, six STs were identified within cow-adapted CC97 and CC151. Two human-adapted STs were isolated from BTM and CQM. Seven human-adapted clonal complexes with eight STs were identified from human samples. One cow-adapted ST was isolated from a human. Antimicrobial susceptibility of the isolates was tested using disc diffusion and broth microdilution methods. Approximately 27% of the isolates were beta-lactam resistant and blaZ gene-positive. S. aureus isolates from human swabs were more likely to carry blaZ compared to isolates from CQM or BTM. S. aureus isolated from cows and humans on the same farm belonged to different STs. CONCLUSION: Humans were more likely to carry beta-lactam-resistant S. aureus compared to cows, and on organic farms only human-adapted blaZ positive STs were isolated from BTM. Moreover, we identified potential spillover events of S. aureus sequence types between host species. The presence of penicillin-resistant-human-adapted S. aureus on both organic and conventional dairy farms highlights a "One Health" concern at the junction of public and animal health requiring further surveillance.

Adaptive staffing can mitigate essential worker disease and absenteeism in an emerging epidemic.

Essential worker absenteeism has been a pressing problem in the COVID-19 pandemic. Nearly 20% of US hospitals experienced staff shortages, exhausting replacement pools and at times requiring COVID-positive healthcare workers to remain at work. To our knowledge there are no data-informed models examining how different staffing strategies affect epidemic dynamics on a network in the context of rising worker absenteeism. Here we develop a susceptible-infected-quarantined-recovered adaptive network model using pair approximations to gauge the effects of worker replacement versus redistribution of work among remaining healthy workers in the early epidemic phase. Parameterized with hospital data, the model exhibits a time-varying trade-off: Worker replacement minimizes peak prevalence in the early phase, while redistribution minimizes final outbreak size. Any "ideal" strategy requires balancing the need to maintain a baseline number of workers against the desire to decrease total number infected. We show that one adaptive strategy-switching from replacement to redistribution at epidemic peak-decreases disease burden by 9.7% and nearly doubles the final fraction of healthy workers compared to pure replacement.

Relationship Between Facility Type and Bulk Tank Milk Bacteriology, Udder Health, Udder Hygiene, and Milk Production on Vermont Organic Dairy Farms.

The primary objective of this cross-sectional observational study was to determine whether bulk tank milk quality, udder health, udder hygiene and milk production outcomes were associated with facility type on organic dairies. A secondary objective was to identify other management-related risk factors associated with bulk tank milk quality, udder health, udder hygiene, and milk production on organic dairy herds in Vermont. We aimed to enroll 40 farms, to compare herds using the 2 most common systems (freestalls, tiestalls) for housing organic dairy cattle in the state with those using a bedded pack during the non-grazing season (typically November-May). Two general styles of bedded packs were observed: cultivated bedded packs and untilled deep bedded packs. Due to the limited number of herds using bedded packs to house lactating dairy cattle in Vermont, we combined untilled and cultivated bedded packs to describe udder hygiene, milk quality, and udder health on these loose-housing systems deeply-bedded with organic material. The study was completed on 21 farms (5 bedded packs, 6 freestalls, 10 tiestalls) before interruption due to the COVID-19 pandemic. Data captured from Dairy Herd Improvement Association records from the test closest to the date of the farm visit included average somatic cell score (SCS), standardized 150-d milk (pounds), % cows with current high SCS (SCS ≥ 4.0), % cows with newly elevated SCS (previous SCS < 4.0 to current ≥ 4.0), and % cows with chronically elevated SCS (SCS ≥ 4.0 last 2 tests). Multivariable linear regression models were used to describe outcomes by facility type, but suffered from limited statistical power due to small group sample sizes. Unconditional comparisons failed to find statistically significant differences between farms grouped by facility type in metrics captured from Dairy Herd Improvement Association test data, bulk tank milk somatic cell count (BTSCC) and aerobic culture data, or udder hygiene scores. A secondary analysis was conducted using univariate linear regression to identify associations between herd management factors and outcomes for all 21 farms combined. Although not all differences found were statistically significant in this secondary analysis combining all farms, numeric differences that may be biologically important are reported showing farms with deeper bedding had a lower BTSCC, lower newly elevated SCS, lower chronically elevated SCS, lower elevated current SCS, lower average SCS, and better udder hygiene metrics. Farms with lower mean udder hygiene scores had numerically lower chronically elevated SCS, lower elevated current SCS, and lower average SCS. We could not reject the null hypothesis that milk quality and udder health outcomes did not differ by facility type, and this does not preclude the existence of biological differences in these outcomes between facility types. The current study provides insight on factors affecting bulk tank milk quality, udder health and hygiene measures on organic dairy farms in Vermont. Bedded packs may be a viable option for confinement housing during the winter non-grazing season for pasture-based herds interested in a loose-housing system in the Northeastern US, but more research such as longitudinal studies with a larger sample size is needed to test this hypothesis.

Exploring the presence of bovine leukemia virus among breast cancer tumors in a rural state.

PURPOSE: The bovine leukemia virus (BLV) is a deltaretrovirus that causes malignant lymphoma and lymphosarcomas in cattle globally and has high prevalence among large scale U.S. dairy herds. Associations between presence of BLV DNA in human mammary tissue and human breast cancer incidence have been reported. We sought to estimate the prevalence of BLV DNA in breast cancer tissue samples in a rural state with an active dairy industry. METHODS: We purified genomic DNA from 56 fresh-frozen breast cancer tissue samples (51 tumor samples, 5 samples representing adjacent normal breast tissue) banked between 2016 and 2019. Using nested PCR assays, multiple BLV tax sequence primers and primers for the long terminal repeat (LTR) were used to detect BLV DNA in tissue samples and known positive control samples, including the permanently infected fetal lamb kidney cell line (FLK-BLV) and blood from BLV positive cattle. RESULTS: The median age of patients from which samples were obtained at the time of treatment was 60 (40-93) and all were female. Ninety percent of patients had invasive ductal carcinoma. The majority were poorly differentiated (60%). On PCR assay, none of the tumor samples tested positive for BLV DNA, despite having consistent signals in positive controls. CONCLUSION: We did not find BLV DNA in fresh-frozen breast cancer tumors from patients presenting to a hospital in Vermont. Our findings suggest a low prevalence of BLV in our patient population and a need to reevaluate the association between BLV and human breast cancer.

The Effectiveness and Adverse Events of Cannabidiol and Tetrahydrocannabinol Used in the Treatment of Anxiety Disorders in a PTSD Subpopulation: An Interim Analysis of an Observational Study.

Background: Anxiety is a condition for which current treatments are often limited by adverse events (AEs). Components of medicinal cannabis, cannabidiol (CBD) and tetrahydrocannabinol (THC), have been proposed as potential treatments for anxiety disorders, specifically posttraumatic stress disorder (PTSD). Objective: To evaluate quality-of-life outcomes after treatment with various cannabis formulations to determine the effectiveness and associated AEs. Methods: An interim analysis of data collected between September 2018 and June 2021 from the CA Clinics Observational Study. Patient-Reported Outcomes Measurement Information System-29 survey scores of 198 participants with an anxiety disorder were compared at baseline and after treatment with medicinal cannabis. The data of 568 anxiety participants were also analyzed to examine the AEs they experienced by the Medical Dictionary for Regulatory Activities organ system class. Results: The median doses taken were 50.0 mg/day for CBD and 4.4 mg/day for THC. The total participant sample reported significantly improved anxiety, depression, fatigue, and ability to take part in social roles and activities. Those who were diagnosed with PTSD (n = 57) reported significantly improved anxiety, depression, fatigue, and social abilities. The most common AEs reported across the whole participant cohort were dry mouth (32.6%), somnolence (31.3%), and fatigue (18.5%), but incidence varied with different cannabis formulations. The inclusion of THC in a formulation was significantly associated with experiencing gastrointestinal AEs; specifically dry mouth and nausea. Conclusions: Formulations of cannabis significantly improved anxiety, depression, fatigue, and the ability to participate in social activities in participants with anxiety disorders. The AEs experienced by participants are consistent with those in other studies.

Defining the Long-Term Clinical Course and Need for Repeat Dilation for Patients With Schatzki Rings.

Schatzki rings (SRs) are a well-known cause of intermittent solid-food dysphagia.1 Although some patients sustain improvement after 1 endoscopic dilation, others require repeated dilations for recurrent symptoms.2-4 SRs are believed to be distinct from strictures caused by gastroesophageal reflux disease. SRs are sharply localized lesions with clearly defined margins, whereas peptic strictures have a more gradual transition between normal and abnormal esophagus to produce a funnel-shaped narrowing.5,6 Consequently, it has been assumed that repeat dilation is less common in SRs dissimilar from medically untreated peptic strictures. The study aim was to identify clinical and radiologic predictors for repeated esophageal dilations in patients with SRs and to assess if peptic stricture-like characteristics of rings correspond to need for repeat dilation.

Imaging Review of Gastrointestinal Motility Disorders.

The motor function of the gastrointestinal tract relies on the enteric nervous system, which includes neurons spanning from the esophagus to the internal anal sphincter. Disorders of gastrointestinal motility arise as a result of disease within the affected portion of the enteric nervous system and may be caused by a wide array of underlying diseases. The etiology of motility disorders may be primary or due to secondary causes related to infection or inflammation, congenital abnormalities, metabolic disturbances, systemic illness, or medication-related side effects. The symptoms of gastrointestinal dysmotility tend to be nonspecific and may cause diagnostic difficulty. Therefore, evaluation of motility disorders requires a combination of clinical, radiologic, and endoscopic or manometric testing. Radiologic studies including fluoroscopy, CT, MRI, and nuclear scintigraphy allow exclusion of alternative pathologic conditions and serve as adjuncts to endoscopy and manometry to determine the appropriate diagnosis. Additionally, radiologist understanding of clinical evaluation of motility disorders is necessary for guiding referring clinicians and appropriately imaging patients. New developments and advances in imaging techniques have allowed improved assessment and diagnosis of motility disorders, which will continue to improve patient treatment options. Online supplemental material is available for this article. ©RSNA, 2022.

Design and implementation of a survey quantifying winter housing and bedding types used on Vermont organic dairy farms.

We conducted a descriptive observational study to quantify the frequency and diversity of winter housing and bedding types used by organic dairy farmers in Vermont. This report describes the survey methods, results, successes, limitations, and lessons learned from administering the survey. Beginning in December 2018, a short questionnaire was administered by web, mail, and telephone to a source population defined as all producers of organic dairy cow milk in Vermont (n = 177) listed in the United States Department of Agriculture Organic Integrity database. Our approach yielded an 82% (n = 145) response from certified organic farms producing cow milk in Vermont at the time of the survey. The 3 most common housing and bedding material combinations used by respondents were tiestall housing with wood (sawdust or shavings) bedding materials (45%), freestall housing with wood bedding materials (14%), and freestall housing with sand bedding (12%). Fifteen percent of respondents reported using more than one type of facility for winter housing of lactating cattle. The median number of lactating cows on farms among respondents was 59.5 (range: 2-400), and the odds of using more than one type of facility to house lactating cows increased positively with the number of lactating cows reported for a herd. Breed distribution was similar across the housing and bedding type categories. An association between frequency of individual cow milk somatic cell count testing and housing type was identified; respondents using freestall sand facilities tested less frequently than respondents using tiestalls with wood bedding. Although the questionnaire length limited the amount of information gathered, the response proportion was exceptional, and overall our survey results provide valuable insight on Vermont organic dairy housing and bedding practices that should inform future extension and outreach efforts for this sector of the dairy industry.

Computerized tomography scan in pre-diagnostic pancreatic ductal adenocarcinoma: Stages of progression and potential benefits of early intervention: A retrospective study.

BACKGROUND: The frequency, nature and timeline of changes on thin-slice (≤3 mm) multi-detector computerized tomography (CT) scans in the pre-diagnostic phase of pancreatic ductal adenocarcinoma (PDAC) are unknown. It is unclear if identifying imaging changes in this phase will improve PDAC survival beyond lead time. METHODS: From a cohort of 128 subjects (Cohort A) with CT scans done 3-36 months before diagnosis of PDAC we developed a CTgram defining CT Stages (CTS) I through IV in the radiological progression of pre-diagnostic PDAC. We constructed Cohort B of PDAC resected at CTS I and II and compared survival in CTS I and II in Cohort A (n = 22 each; control natural history cohort) vs Cohort B (n = 33 and 72, respectively; early interception cohort). RESULTS: CTs were abnormal in 16% and 85% at 24-36 and 3-6 months respectively, before PDAC diagnosis. The PDAC CTgram stages, findings and median lead times (months) to clinical diagnosis were: CTS I: Abrupt duct cut-off/duct dilatation (-12.8); CTS II: Low density mass confined to pancreas (-9.5), CTS III: Peri-pancreatic infiltration (-5.8), CTS IV: Distant metastases (only at diagnosis). PDAC survival was better in cohort B than in cohort A despite inclusion of lead time in Cohort A: CTS I (36 vs 17.2 months, p = 0.03), CTS II (35.2 vs 15.3 months, p = 0.04). CONCLUSION: Starting 12-18 months before PDAC diagnosis, progressive and increasingly frequent changes occur on CT scans. Resection of PDAC at the time of pre-diagnostic CT changes is likely to provide survival benefit beyond lead time.

CT for Evaluation of Acute Gastrointestinal Bleeding.

Acute gastrointestinal (GI) bleeding is common and necessitates rapid diagnosis and treatment. Bleeding can occur anywhere throughout the GI tract and may be caused by many types of disease. The variety of enteric diseases that cause bleeding and the tendency for bleeding to be intermittent may make it difficult to render a diagnosis. The workup of GI bleeding is frequently prolonged and expensive, with examinations commonly needing to be repeated. The use of computed tomography (CT) for evaluation of acute GI bleeding is gaining popularity because it can be used to rapidly diagnose active bleeding and nonbleeding bowel disease. The CT examinations used to evaluate acute GI bleeding include CT angiography and multiphase CT enterography. Understanding the clinical evaluation of acute GI bleeding, including the advantages and limitations of endoscopic evaluation, is necessary for the appropriate selection of patients who may benefit from CT. Multiphase CT enterography is used primarily to evaluate stable patients who have undergone upper and lower endoscopy without identification of a bleeding source. CT angiography is used to examine stable and unstable patients who respond to resuscitation, are believed to be actively bleeding, and are considered unlikely to have an upper GI source of hemorrhage. In the emergent setting, CT may yield critical information regarding the presence, location, and cause of active bleeding-data that can guide the choice of subsequent therapy. Recent developments in the use of and techniques for performing CT angiography have made it a potential first-line tool for evaluating acute GI bleeding. ©RSNA, 2018.

J Pouch: Imaging Findings, Surgical Variations, Natural History, and Common Complications.

Ileal pouch-anal anastomosis, or J pouch, surgery has become the procedure of choice for treatment of medically refractory ulcerative colitis and familial adenomatous polyposis. Overall, this operation is associated with a low rate of postoperative morbidity and good long-term function. However, when complications develop, there is a heavy reliance on imaging to facilitate an accurate diagnosis. Reported postoperative complication rates range from 5% to 35%. Complications generally can be categorized as structural, inflammatory, or neoplastic conditions. Structural complications include leaks, strictures, afferent and efferent limb syndromes, and pouch prolapse. Inflammatory conditions include cuffitis, pouchitis, and Crohn disease of the pouch. In addition, a variety of neoplastic conditions can develop in the pouch. Overall, pouchitis and leaks are the most common complications, occurring in up to 50% and 20% of individuals, respectively. Many imaging modalities are used to evaluate the J pouch and associated postoperative complications. The indications and various surgical techniques for J pouch surgery, normal postoperative appearance of the pouch, and most common associated complications are reviewed. In addition, the various imaging findings associated with J pouch surgery are described and illustrated. The radiologist's familiarity with the potential complications of the pouch can facilitate appropriate imaging, hasten an accurate diagnosis, and aid in rendering proper management. ©RSNA, 2018.

Transmission dynamics of intramammary infections caused by Corynebacterium species.

The development of reliable models for transmission of intramammary infections (IMI) is the subject of extensive research. Such models are useful to enhance the identification and understanding of factors that affect pathogen-specific IMI dynamics. Longitudinal transmission models are valuable for predicting infection outbreak risks, quantifying the effectiveness of response tactics, and performing response planning. In this work, we focused on modeling Corynebacterium spp. by using a compartmental model. Previous investigations have considered modeling the transmission dynamics of several bacterial pathogens, but not Corynebacterium spp. We established a Corynebacterium spp. Susceptible-Infectious-Susceptible (SIS) model. We simulated the model numerically by using parameters that we estimated by a generalized linear model approach, using month of study as the time variable. The data, from which the parameters of the model were estimated, were obtained in a field trial conducted in 2 US dairy herds. Altogether, 786 cows were sampled at least once during the 13-mo study period. The total number of quarter milk cultures and cases of IMI caused by Corynebacterium spp. were 11,744 and 556, respectively, in farm A; the corresponding figures for farm B were 11,804 and 179. Our modeling study included only transmission from persistent IMI caused by Corynebacterium spp. within the lactation pens. The rate of new infections was significantly related to preexisting IMI in both farms, underscoring the importance of preexisting Corynebacterium spp. IMI for the transmission of Corynebacterium spp. within lactation pens. The estimated basic reproduction numbers (R0) in the 2 farms were 1.18 and 0.98, respectively. The nonsignificant disparity in R0 was associated with significant differences in cure rates between farms.

Radiological Response Is Associated With Better Long-Term Outcomes and Is a Potential Treatment Target in Patients With Small Bowel Crohn's Disease.

OBJECTIVES: Crohn's disease (CD) management targets mucosal healing on ileocolonoscopy as a treatment goal. We hypothesized that radiologic response is also associated with better long-term outcomes. METHODS: Small bowel CD patients between 1 January 2002 and 31 October 2014 were identified. All patients had pre-therapy computed tomography enterography (CTE)/magnetic resonance enterography (MRE) with follow-up CTE or MRE after 6 months, or 2 CTE/MREs≥6 months apart while on maintenance therapy. Radiologists characterized inflammation in up to five small bowel lesions per patient. At second CTE/MRE, complete responders had all improved lesions, non-responders had worsening or new lesions, and partial responders had other scenarios. CD-related outcomes of corticosteroid usage, hospitalization, and surgery were assessed using Kaplan-Meier survival analysis and multivariable Cox models. RESULTS: CD patients (n=150), with a median disease duration of 9 years, had 223 inflamed small bowel segments (76 with strictures and 62 with penetrating, non-perianal disease), 49% having ileal distribution. Fifty-five patients (37%) were complete radiologic responders, 39 partial (26%), and 56 non-responders (37%). In multivariable Cox models, complete and partial response decreased risk for steroid usage by over 50% (hazard ratio (HR)s: 0.37 (95% confidence interval (CI), 0.21-0.64); 0.45 (95% CI, 0.26-0.79)), and complete response decreased the risk of subsequent hospitalizations and surgery by over two-thirds (HRs: HR, 0.28 (95% CI, 0.15-0.50); HR, 0.34 (95% CI, 0.18-0.63)). CONCLUSIONS: Radiological response to medical therapy is associated with significant reductions in long-term risk of hospitalization, surgery, or corticosteroid usage among small bowel CD patients. These findings suggest the significance of radiological response as a treatment target.

Evaluation of Patient Tolerance and Small-Bowel Distention With a New Small-Bowel Distending Agent for Enterography.

OBJECTIVE: The objective of our study was to compare a flavored beverage containing a thickening agent for enterography with a low-Hounsfield-value barium suspension for side effects, taste, subjects' willingness to repeat the drinking protocol, and small-bowel distention. SUBJECTS AND METHODS: The following five drinking protocols were administered to 10 volunteers: 1000 mL of flavored beverage followed by 350 mL of water, 1500 mL of flavored beverage, 900 mL of low-Hounsfield-value barium suspension followed by 450 mL of water, 1350 mL of low-Hounsfield-value barium suspension followed by 150 mL of water, and 1500 mL of water. MR images were obtained 50 and 60 minutes after initiation of drinking. Subjects completed a questionnaire evaluating the side effects, the taste of the drink, and their willingness to repeat the drinking protocol. Reviewers assigned scores evaluating small-bowel distention and ranked the examinations in order of preference. RESULTS: There was no significant difference in nausea or vomiting among the protocols (p = 0.20 and 0.42, respectively), but larger volumes of flavored beverage and low-Hounsfield-value barium suspension resulted in more cramping and diarrhea (p = 0.001 and 0.002, respectively). The taste of the low-Hounsfield-value barium suspension was rated the worst (p < 0.0001). The subjects' willingness to repeat the drinking protocol was highest for the 1000 mL of flavored beverage or water alone (p < 0.05). There were no significant differences in subjective small-bowel distention except that water was rated the worst by two of the three readers (p < 0.02). There was no significant difference in the diameter of the most dis-tended small bowel for any segment or reader (p > 0.23). CONCLUSION: A flavored beverage containing a thickening agent has a similar side effect profile and results in equivalent small-bowel distention compared with a low-Hounsfield-value barium suspension, but subjects rate taste and their willingness to repeat the drinking protocol higher for this new agent.

A modern approach for epitope prediction: identification of foot-and-mouth disease virus peptides binding bovine leukocyte antigen (BoLA) class I molecules.

Major histocompatibility complex (MHC) class Imolecules regulate adaptive immune responses through the presentation of antigenic peptides to CD8+ T cells. Polymorphisms in the peptide binding region of class I molecules determine peptide binding affinity and stability during antigen presentation, and different antigen peptide motifs are associated with specific genetic sequences of class I molecules. Understanding bovine leukocyte antigen (BoLA), peptide-MHC class I binding specificities may facilitate development of vaccines or reagents for quantifying the adaptive immune response to intracellular pathogens, such as foot-and-mouth disease virus (FMDV). Six synthetic BoLA class I (BoLA-I) molecules were produced, and the peptide binding motif was generated for five of the six molecules using a combined approach of positional scanning combinatorial peptide libraries (PSCPLs) and neural network-based predictions (NetMHCpan). The updated NetMHCpan server was used to predict BoLA-I binding peptides within the P1 structural polyprotein sequence of FMDV (strain A24 Cruzeiro) for Bo-LA-1*01901, BoLA-2*00801, BoLA-2*01201, and BoLA-4*02401. Peptide binding affinity and stability were determined for these BoLA-I molecules using the luminescent oxygen channeling immunoassay (LOCI) and scintillation proximity assay (SPA). The functional diversity of known BoLA alleles was predicted using theMHCcluster tool, and functional predictions for peptide motifs were compared to observed data from this and prior studies. The results of these analyses showed that BoLA alleles cluster into three distinct groups with the potential to define BBoLA supertypes.^ This streamlined approach identifies potential T cell epitopes from pathogens, such as FMDV, and provides insight into T cell immunity following infection or vaccination.

CT enterography: technical and interpretive pitfalls.

CT enterography is a first-line test at many institutions to investigate potential small bowel disorders. While numerous articles have focused on the ability of CT enterography to diagnose and stage Crohn's disease, small bowel neoplasia, and malabsorptive or vascular disorders, this article reviews CT enterography limitations, technical and interpretive pitfalls, image review tactics, and complementary radiologic and endoscopic examinations to improve diagnostic accuracy. CT enterography limitations include its inability to demonstrate isolated mucosal abnormalities such as aphthous ulcers and its use of ionizing radiation. The most common technical pitfall of CT enterography is inadequate small bowel distention resulting from inadequate ingestion, gastric retention, or rapid small bowel transit of a large volume of neutral enteric contrast material. Additionally, segments of jejunum are frequently collapsed. Interpretive pitfalls commonly result from peristaltic contractions, transient intussusception and opaque intraluminal debris. Opaque debris is especially problematic during multiphasic CT enterography performed to identify potential small bowel sources of obscure gastrointestinal bleeding. False-negative examinations may result from inadequate radiation dose. Examinations complementary to CT enterography include small bowel follow through, enteroclysis, CT enteroclysis, MR enterography, MR enteroclysis, capsule endoscopy, and balloon-assisted endoscopy. Properly performed and accurately interpreted CT enterography contributes to the diagnosis and management of small bowel disease by itself and as a complement to other radiologic and optical small bowel imaging examinations.

Observer performance for adaptive, image-based denoising and filtered back projection compared to scanner-based iterative reconstruction for lower dose CT enterography.

PURPOSE: The purpose of this study was to compare observer performance for detection of intestinal inflammation for low-dose CT enterography (LD-CTE) using scanner-based iterative reconstruction (IR) vs. vendor-independent, adaptive image-based noise reduction (ANLM) or filtered back projection (FBP). METHODS: Sixty-two LD-CTE exams were performed. LD-CTE images were reconstructed using IR, ANLM, and FBP. Three readers, blinded to image type, marked intestinal inflammation directly on patient images using a specialized workstation over three sessions, interpreting one image type/patient/session. Reference standard was created by a gastroenterologist and radiologist, who reviewed all available data including dismissal Gastroenterology records, and who marked all inflamed bowel segments on the same workstation. Reader and reference localizations were then compared. Non-inferiority was tested using Jackknife free-response ROC (JAFROC) figures of merit (FOM) for ANLM and FBP compared to IR. Patient-level analyses for the presence or absence of inflammation were also conducted. RESULTS: There were 46 inflamed bowel segments in 24/62 patients (CTDIvol interquartile range 6.9-10.1 mGy). JAFROC FOM for ANLM and FBP were 0.84 (95% CI 0.75-0.92) and 0.84 (95% CI 0.75-0.92), and were statistically non-inferior to IR (FOM 0.84; 95% CI 0.76-0.93). Patient-level pooled confidence intervals for sensitivity widely overlapped, as did specificities. Image quality was rated as better with IR and AMLM compared to FBP (p < 0.0001), with no difference in reading times (p = 0.89). CONCLUSIONS: Vendor-independent adaptive image-based noise reduction and FBP provided observer performance that was non-inferior to scanner-based IR methods. Adaptive image-based noise reduction maintained or improved upon image quality ratings compared to FBP when performing CTE at lower dose levels.

NSAID enteropathy: appearance at CT and MR enterography in the age of multi-modality imaging and treatment.

CT and MR enterography and capsule endoscopy are increasingly used as routine diagnostic tests for patients with potential small bowel disorders and obscure gastrointestinal bleeding. Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used drugs that disrupt prostaglandin synthesis and result in a variety of localized complications within the small bowel ranging from ulcer formation to characteristic circumferential strictures, or diaphragms. NSAID enteropathy encompasses this spectrum of acute and chronic inflammatory sequelae, and is associated with typical findings at capsule endoscopy and surgery. Herein we review the typical clinical presentation of NSAID enteropathy, in addition to its endoscopic appearances, focusing on imaging findings at cross-sectional enterography. Multiple, short-segment strictures are the hallmarks of imaging diagnosis. Strictures may have minimal hyperenhancement or wall thickening, but these findings are typically symmetric and circumferential with respect to the bowel lumen. Multifocal Crohn's strictures, and occasionally radiation-induced strictures or adhesions, will mimic NSAID diaphragms. Multi-phase or multi-sequence imaging at CT and MR enterography increase diagnostic confidence in stricture presence. Strategies for subsequent workup and therapy after enterography are also discussed. Given the frequent use of NSAIDs and typical appearance of these strictures, knowledge of characteristic imaging findings can be particularly useful when evaluating patients with anemia and recurrent small bowel obstruction.

Clinical characteristics and imaging features of small bowel adenocarcinomas in Crohn's disease.

PURPOSE: Small bowel adenocarcinoma is uncommon in patients with Crohn's disease but has an extremely poor prognosis. There is a paucity of data on the clinical characteristics and radiologic features of this entity. We sought to update our institutional experience with small bowel adenocarcinoma occurring in the setting of Crohn's disease and to systematically re-examine pre-operative imaging findings. METHODS: Medical records were abstracted to identify all patients with Crohn's disease and small bowel adenocarcinoma who were evaluated at Mayo Clinic, Rochester, Minnesota and Mayo Clinic, Scottsdale, Arizona between 1976 and 2012. Clinical, demographic, and outcomes data were obtained for each patient. Pre-diagnosis radiologic imaging was re-evaluated by two gastrointestinal radiologists. RESULTS: Thirty-four patients (21 males) were identified. Median ages at Crohn's disease and cancer diagnoses were 22.4 and 52.9 years, respectively. Median follow-up after cancer diagnosis was 272.0 days; 22 patients (64.7%) had persistent or recurrent adenocarcinoma at last follow-up. 1- and 2-year mortality rates were 29.6% and 48.0%. Pre-operative imaging studies were available for re-review in 14 cases. Features concerning for malignancy included annular mass, nodularity at the extraluminal margins of the mass, and perforation. Nearly all tumors arose in regions of chronic inflammation and caused luminal narrowing with pre-stenotic dilatation. CONCLUSIONS: Small bowel adenocarcinoma is rare in patients with Crohn's disease but results in significant mortality. CT or MR imaging findings can be suggestive of the pre-operative diagnosis, but it is usually diagnosed at an advanced stage with laparotomy.

Diet and diabetes.

BACKGROUND: Guidelines for the prevention and management of type 2 diabetes mellitus (T2DM) reinforce lifestyle management, yet advice to guide general practitioners on principles around dietary choices is needed. OBJECTIVE: This article provides current evidence regarding the differing diets in diabetes prevention and management once T2DM arises, including the role in management of complications such as hypoglycaemia. DISCUSSION: Diets should incorporate weight maintenance or loss, while complementing changes in physical activity to optimise the metabolic effects of dietary advice. Using a structured, team-care approach supports pragmatic and sustainable individualised plans, while incorporating current evidence-based dietary approaches.