International external validation of a stratification tool to identify branch-duct intraductal papillary mucinous neoplasms at lowest risk of progression.

BACKGROUND: Identifying branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs) at lowest risk of progression may allow for a reduced intensity of surveillance. OBJECTIVE: We aimed to externally validate the previously developed Dutch-American Risk stratification Tool (DART-1; https://rtools.mayo.edu/DART/), which identifies cysts at low risk of developing worrisome features (WFs) or high-risk stigmata (HRS). METHODS: Three prospective cohorts of individuals under surveillance for BD-IPMNs were combined, independent from the original development cohort. We assessed the performance (discrimination and calibration) of DART-1, a multivariable Cox-proportional logistic regression model with five predictors for the development of WFs or HRS. RESULTS: Of 832 individuals (mean age 77 years, SD 11.5) under surveillance for a median of 40 months (IQR 44), 163 (20%) developed WFs or HRS. DART-1's discriminative ability (C-statistic 0.68) was similar to that in the development cohort (0.64-0.72) and showed moderate calibration. DART-1 adequately estimated the risk for patients in the middle risk quintile, and slightly underestimated it in the lowest quintiles. Their range of predicted versus observed 3-year risk was 0%-0% versus 0%-3.7% for Q1; 0.3%-0.4% versus 3%-11% for Q2; and 2.6%-3% versus 2.4%-9.8% for Q3. The development of WFs or HRS was associated with pancreatic cancer (p < 0.001). Vice versa, in absence of WFs or HRS, the risk of malignancy was low (0.3%). CONCLUSIONS: The performance of DART-1 to predict the development of WFs or HRS in BD-IPMN was validated in an external international cohort, with a discriminative ability equal as in the development cohort. Risk estimations were most accurate for patients with BD-IPMNs in the middle risk quintile and slightly underestimated in the lowest quintiles.

Dielectric Meta-Holograms Enabled with Dual Magnetic Resonances in Visible Light.

Efficient transmission-type meta-holograms have been demonstrated using high-index dielectric nanostructures based on Huygens' principle. It is crucial that the geometry size of building blocks be judiciously optimized individually for spectral overlap of electric and magnetic dipoles. In contrast, reflection-type meta-holograms using the metal/insulator/metal scheme and geometric phase can be readily achieved with high efficiency and small thickness. Here, we demonstrate a general platform for design of dual magnetic resonance based meta-holograms based on the geometric phase using silicon nanostructures that are quarter wavelength thick for visible light. Significantly, the projected holographic image can be unambiguously observed without a receiving screen even under the illumination of natural light. Within the well-developed semiconductor industry, our ultrathin magnetic resonance-based meta-holograms may have promising applications in anticounterfeiting and information security.

Collagenous Gastritis in a Young Female With IgA Deficiency.

Collagenous gastritis, without colonic involvement, is exceptionally rare. It is not known to be associated with IgA deficiency and scleroderma. This is the first report of this type of association. We present a 26-year-old white female with a past medical history of gastroesophageal reflux disease and scleroderma. She was evaluated for complaints of abdominal pain and diarrhea. Esophagogastroduodenoscopy showed gastritis and duodenitis. Colonoscopy was normal. The histopathological report showed collagenous gastritis and focal lymphocytic duodenitis. A definitive treatment has not been established for this condition. Reporting such cases furthers understanding of the disease and will help to establish diagnostic criteria and to develop therapeutic strategies.

Whipple's Disease Manifested as Recurrent Ascites.

Whipple's disease commonly presents as chronic diarrhea and abdominal pain. Ascites is an uncommon presentation of Whipple's disease. Here, we report a rare case of a 47-year-old male who presented with diarrhea and abdominal distention for three months. The physical examination was significant for ascites. Serum albumin was low and serum-to-ascites albumin gradient was < 1.1 g/dl. This suggested that ascites was less likely to be present due to portal hypertension. Enteroscopy showed erythematous duodenum and jejunum; biopsy was suggestive of periodic acid-Schiff stain (PAS) positive macrophages consistent with Whipple's disease. During the hospital course, the patient improved with intravenous (IV) ceftriaxone.