Utility of Hook Sign in the Diagnosis of Median Arcuate Ligament Syndrome.

BACKGROUND: Median arcuate ligament syndrome (MALS) is a clinical syndrome caused by compression of the celiac artery by the median arcuate ligament that often manifests with nonspecific abdominal pain. Identification of this syndrome is often dependent on imaging of compression and upward bending of the celiac artery by lateral computed tomography angiography, the so-called "hook sign." The purpose of this study was to assess the relationship of radiologic characteristics of the celiac artery to clinically relevant MALS. METHODS: An institutional review board-approved retrospective chart review from 2,000 to 2,021 of 293 patients at a tertiary academic center diagnosed with celiac artery compression (CAC) was performed. Patient demographics and symptoms of 69 patients who were diagnosed with symptomatic MALS were compared to 224 patients without MALS (but with CAC) per electronic medical record review. Computed tomography angiography images were reviewed and the fold angle (FA) was measured. The presence of a hook sign (defined as a visual FA < 135°), as well as stenosis (defined as >50% of luminal narrowing on imaging) were recorded. Wilcoxon rank-sum test and Chi-squared test were used for comparative analysis. Logistic model was run to relate the presence of MALS with comorbidities and radiographic findings. RESULTS: Imaging was available in 59 patients (25 males, 34 females) and 157 patients (60 males, 97 females) with and without MALS, respectively. Patients with MALS were more likely to have a more severe FA (120.7 ± 33.6 vs. 134.8 ± 27.9, P = 0.002). Males with MALS were also more likely to have a more severe FA compared with males without MALS (111.1 ± 33.7 vs. 130.4 ± 30.4, P = 0.015). In patients with body mass index (BMI) >25, MALS patients also had narrower FA compared with patients without MALS (112.6 ± 30.5 vs. 131.7 ± 30.3, P = 0.001). The FA was negatively correlated with BMI in patients with CAC. The hook sign and stenosis were associated with diagnosis of MALS (59.3% vs. 28.7%, P < 0.001, and 75.7% vs. 45.2%, P < 0.001, respectively). In logistic regression, pain, stenosis, and a narrow FA were statistically significant predictors of the presence of MALS. CONCLUSIONS: The upward deflection of the celiac artery in patients with MALS is more severe compared with patients without MALS. Consistent with prior literature, this bending of the celiac artery is negatively correlated with BMI in patients with and without MALS. When demographic variables and comorbidities are considered, a narrow FA is a statistically significant predictor of MALS. Regardless of MALS diagnosis, a hook sign was associated with narrower FA. While demographics and imaging findings may inform MALS diagnosis, clinicians should not rely on a visual assessment of a hook sign but should quantitatively measure the anatomic bending angle of the celiac artery to assist with the diagnosis and understand the outcomes.

Early Flexible Sigmoidoscopy Improves Clinical Outcomes in Acute Severe Ulcerative Colitis.

Objectives: Guidelines recommend performing a flexible sigmoidoscopy in patients hospitalized with acute severe ulcerative colitis (ASUC). However, it is unclear if time to sigmoidoscopy affects relevant clinical outcomes. We aimed to assess the impact of early sigmoidoscopy on clinical outcomes using a well-characterized cohort of patients with ASUC. Methods: This is a single-center, retrospective study of all patients hospitalized with ASUC from January 1, 2012 to November 1, 2021. Early sigmoidoscopy was defined as occurring within 72 hours of admission while delayed sigmoidoscopy was defined as occurring >72 hours after admission. Primary outcomes were cumulative days of intravenous (IV) corticosteroid (CS) use, length of hospital stay, and colectomy rates. Secondary outcomes were time to infliximab (IFX) rescue and inpatient opioid medication use. Results: A total of 112 patients hospitalized with ASUC who underwent sigmoidoscopy were included in the analysis. Eighty-seven patients (78%) had early sigmoidoscopy and 25 (22%) had delayed sigmoidoscopy. Patients in the early sigmoidoscopy group were exposed to significantly fewer days of IV CS (4.5 vs 9.2 days; P < .001), had shorter hospital stays (6.4 vs 19.3 days; P < .001), and shorter time to IFX rescue (3.5 vs 6.4 days; P = .004). Rates of colectomy in the early and delayed sigmoidoscopy groups were 17% versus 28%, respectively (P = .23). Longer time to sigmoidoscopy was associated with a 16% increased risk of colectomy (HR = 1.16, P = .002). Conclusions: In this well-characterized cohort, early sigmoidoscopy in ASUC was associated with favorable clinical outcomes. These findings highlight the benefits of early sigmoidoscopy in patients with ASUC. Larger prospective studies are needed to corroborate these findings.

Prevalence and Characteristics of Patients with Median Arcuate Ligament Syndrome in a Cohort Diagnosed with Celiac Artery Compression.

BACKGROUND: Median arcuate ligament syndrome (MALS) is a frequent differential diagnosis in patients with postprandial abdominal symptoms, but diagnosis remains challenging. The aim of this study was to identify characteristics of patients who had MALS compared with non-MALS patients among a cohort of patients diagnosed with celiac artery compression (CAC). STUDY DESIGN: An IRB-approved retrospective chart review (2000 to 2021) of patients at our institution with a discharge diagnosis of CAC was performed. Medical record review for clinical symptoms and findings consistent with MALS was performed. RESULTS: Two hundred ninety-three patients with a diagnosis of CAC were identified; 59.7% were women, and average age was 63.9 ± 20.2 years. Sixty-nine (23.5%) patients with CAC had MALS. There were no significant differences in sex or race between MALS and non-MALS patients, but MALS patients were younger (55.7 vs 68.1, p < 0.001). There was no significant difference in gastrointestinal comorbidities between the 2 groups. Patients with MALS were less likely to have diabetes (12.5% vs 26.9%), renal disease (4.6% vs 8.2%), hypertension (41.5% vs 70.3%), mesenteric atherosclerotic disease (14% vs 61.9%), and peripheral artery disease (15.0% vs 39.7%). CONCLUSIONS: We demonstrate a novel observation that MALS patients tend to have fewer atherosclerotic characteristics than non-MALS patients with CAC. Patients in our study with MALS were more likely to be younger, women, and presenting with epigastric pain. MALS patients had a significantly lower incidence of diabetes, hypertension, renal disease, mesenteric artery disease, and peripheral arterial disease compared with the non-MALS group. An important clinically relevant feature of MALS patients may be their lack of atherosclerotic phenotype compared with non- MALS patients with CAC.

Effect of obesity on vedolizumab response in inflammatory bowel disease.

Background: Vedolizumab is used in inflammatory bowel disease (IBD), administered as a non-weight-based fixed dose. A higher body mass index (BMI) is associated with lower serum vedolizumab levels, but it is unclear whether it is associated with an unfavorable response to vedolizumab. We examined the relationship between BMI and the need for dose escalation, and the overall response to vedolizumab in IBD patients. Methods: This was a single-center, retrospective study of IBD patients who received vedolizumab between 1st July 2014 and 1st September 2020. The primary outcome was need for vedolizumab dose escalation or discontinuation. Secondary outcomes were steroid-free clinical remission (SFCR), endoscopic remission, and normal serum C-reactive protein (CRP). Outcomes were compared between patients with BMI <30 kg/m2 (non-obese) or ≥30 kg/m>2 (obese). Results: 190 patients were included, with a median follow-up time of 21 months. Median age was 37 years, 50.5% were male, and median BMI was 24.8 kg/m2 (75.3% of patients had BMI <30 kg/m2). Vedolizumab was dose-escalated in 48.9% of the obese group vs. 42% of the non-obese group (P=0.4). Vedolizumab was discontinued in 31.9% of the obese group vs. 53.2% of the non-obese group (P=0.01). The rate of CRP normalization was significantly lower in the obese group (46.2% vs. 66%, P=0.03). SFCR and endoscopic remission rates were not significantly different between the groups. Conclusions: Obesity was not associated with higher rates of vedolizumab dose escalation. However, it was associated with lower rates of vedolizumab discontinuation and CRP normalization, but not SFCR or endoscopic remission.