ABSTRACT
BACKGROUND: A fundamental understanding of the impact of bariatric surgery (BRS) on mechanisms of colorectal carcinogenesis is limited. For instance, studies report a reduced risk of colorectal cancer in females but not in males after BRS. We examined whether this sex-specific difference existed at the earlier polyp development stage. METHODS: This retrospective cohort study included 281,417 adults from the 2012-2020 MarketScan database. We compared polyps rates on colonoscopy in four groups: post- vs. pre-BRS (treatment) to post- vs. pre-severe obesity (SO) diagnosis (control). We focused our main analysis on a propensity-matched sample that yielded a balanced distribution of covariates in our four groups (n = 9680 adults, 21.9% males). We also adjusted for important covariates. RESULTS: Metabolic syndrome parameters improved after bariatric surgery and worsened after severe obesity diagnosis (p < 0.05). The rate of polyps was 46.7% at a median of 0.5 years pre-BRS and 47.9% at a median of 0.6 years pre-SO diagnosis. The polyps rate was 45.4% at a median (range) of 3.2 (1.0-8.5) years post-BRS. Conversely, 53.8% of adults had polyps at 3.0 (1.0-8.6) years post-SO. There was no change in the risk of colorectal polyps in males or females post- vs. pre-BRS. However, the risk of polyps was higher in males (OR = 1.32, 95% CI: 1.02-1.70) and females (OR = 1.29, 95% CI: 1.13-1.47) post- vs. pre-SO. When compared to the control group (SO), the odds ratios for colorectal polyps were lower for males and females after bariatric surgery (OR = 0.63, 95% CI: 0.44-0.90, and OR = 0.79, 95% CI: 0.66-0.96, respectively). CONCLUSIONS: Obesity is associated with an increased risk of colorectal polyps, an effect that is ameliorated after bariatric surgery. These data are relevant for studies investigating colorectal carcinogenesis mechanisms.
ABSTRACT
Leukocytoclastic vasculitis (LCV) is rarely associated with anti-tumor necrosis factor [TNF] α therapy. We report a 22-year-old man with new onset of a pustular rash on his bilateral upper and lower extremities while on adalimumab therapy for Crohn's disease. Skin biopsy of the affected area showed perivascular extravasation of erythrocytes, neutrophils, eosinophils and vascular damage surrounding blood vessels associated with fibrin, consistent with LCV. Patient was treated with topical steroids and subsequently transitioned to ustekinumab therapy with follow-up colonoscopy showing minimal active disease. Our report highlights the association of a unique dermatologic autoimmune manifestation with TNF-targeted therapy in a patient with Crohn's disease.
ABSTRACT
PURPOSE: Guinea pig sensitization assays provide a critical tool in toxicological testing. Here, we investigate the relative sensitivities of the Guinea Pig Maximization Test (GPMT), the Open Epicutaneous Test (OET), and the Buehler test on seven common compounds. METHODS: Seven compounds (formalin, nickel sulfate, 2-benzothiazolethiol, neomycin sulfate, potassium dichromate, ethylenediamine, dihydrochloride, and cinnamyl alcohol) were investigated on 15 guinea pigs per assay. Differences between each assay were investigated individually for each compound in question, and cumulative comparisons were also performed. RESULTS: Cumulatively, differences in rates of sensitization between the GPMT and OET did not reach statistical significance; however, both tests produced higher sensitization rates than the Buehler test (1% significance level). Comparisons for individual compounds are outlined within the main text. CONCLUSIONS: Our results indicate a possible role for the OET in the testing of weakly allergenic compounds. Similarly, the Buehler test may hold greatest utility in the examination of strongly allergenic compounds, where high sensitivity is not necessary and limited exposure to subjects is desired. These findings may help guide experimental protocols and considerations.
