Background/Objectives: Acquired reactive perforating collagenosis (ARPC) is a rare entity usually occurring in adults with systemic diseases such as diabetes mellitus, chronic kidney disease (CKD), cardiovascular diseases, and malignancies, although drug-related and trauma-induced cases have also been reported. Given its rarity and the lack of consensus on optimal management, we conducted a systematic review to summarize updated diagnostic and therapeutic insights into ARPC. Additionally, we report a case of ARPC associated with CKD. Methods: This study was conducted in accordance with the PRISMA 2020 (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A literature search was performed in the PubMed database between May–September 2025. The search strategy targeted open-access, primary human studies, published within the last 15 years, available in English, and including adult patients with histopathologically confirmed ARPC. Results: Twenty-seven studies, predominantly case reports and case series, were included. The mean patient age was 60.8 ± 14.4 years. Only one case occurred in the absence of comorbidities, while most subjects had underlying systemic diseases. Drug-induced cases were also described. Clinically, ARPC should be suspected in patients presenting with pruritic papules/nodules with central keratotic plugs. Additional diagnostic tools include dermoscopy and reflectance confocal microscopy. However, histopathological evidence of transepidermal elimination of altered collagen fibers is mandatory. The current treatments of ARPC include antihistamines, keratolytics, topical/intralesional/oral corticosteroids, topical/systemic retinoids, phototherapy, dupilumab and allopurinol. Other therapies have been reported across the literature, including emerging ones. Conclusions: Once ARPC is diagnosed, a thorough evaluation for underlying diseases, including malignancies, is essential. Clinical trials are warranted to define optimal therapeutic strategies.

Background: EUS-guided fine-needle biopsy is the procedure of choice for the diagnosis of pancreatic ductal adenocarcinoma (PDAC). Nevertheless, the samples obtained are small and require expertise in pathology, whereas the diagnosis is difficult in view of the scarcity of malignant cells and the important desmoplastic reaction of these tumors. With the help of artificial intelligence, the deep learning architectures produce a fast, accurate, and automated approach for PDAC image segmentation based on whole-slide imaging. Given the effectiveness of U-Net in semantic segmentation, numerous variants and improvements have emerged, specifically for whole-slide imaging segmentation. Methods: In this study, a comparison of 7 U-Net architecture variants was performed on 2 different datasets of EUS-guided fine-needle biopsy samples from 2 medical centers (31 and 33 whole-slide images, respectively) with different parameters and acquisition tools. The U-Net architecture variants evaluated included some that had not been previously explored for PDAC whole-slide image segmentation. The evaluation of their performance involved calculating accuracy through the mean Dice coefficient and mean intersection over union (IoU). Results: The highest segmentation accuracies were obtained using Inception U-Net architecture for both datasets. PDAC tissue was segmented with the overall average Dice coefficient of 97.82% and IoU of 0.87 for Dataset 1, respectively, overall average Dice coefficient of 95.70%, and IoU of 0.79 for Dataset 2. Also, we considered the external testing of the trained segmentation models by performing the cross evaluations between the 2 datasets. The Inception U-Net model trained on Train Dataset 1 performed with the overall average Dice coefficient of 93.12% and IoU of 0.74 on Test Dataset 2. The Inception U-Net model trained on Train Dataset 2 performed with the overall average Dice coefficient of 92.09% and IoU of 0.81 on Test Dataset 1. Conclusions: The findings of this study demonstrated the feasibility of utilizing artificial intelligence for assessing PDAC segmentation in whole-slide imaging, supported by promising scores.

Endoscopic ultrasound (EUS) gained wide acceptance as the diagnostic and minimally invasive therapeutic approach for intra-luminal and extraluminal gastrointestinal, as well as various non-gastrointestinal lesions. Since its introduction, EUS has undergone substantial technological advances. This multi-centric study is a retrospective analysis of a prospectively maintained database of patients who underwent EUS for the evaluation of lesions located within the gastrointestinal tract and the proximal organs. It aimed to extensively assess in dynamic the dual-center EUS experience over the course of the past 20 years. Hence, we performed a population study and an overall assessment of the EUS procedures. The performance of EUS-FNA/FNB in diagnosing pancreatic neoplasms was evaluated. We also investigated the contribution of associating contrast-enhanced ultrasound imaging (CE-EUS) with EUS-FNA/FNB for differentiating solid pancreatic lesions or cystic pancreatic lesions. A total of 2935 patients undergoing EUS between 2002–2021 were included, out of which 1880 were diagnostic EUS and 1052 EUS-FNA/FNB (80% FNA and 20% FNB). Therapeutic procedures performed included endoscopic transmural drainage of pancreatic fluid collections, celiac plexus block and neurolysis, while diagnostic EUS-like CE-EUS (20%) and real-time elastography (12%) were also conducted. Most complications occurred during the first 7 days after EUS-FNA/FNB or pseudocyst drainage. EUS and the additional tools have high technical success rates and low rates of complications. The EUS methods are safe, cost effective and indispensable for the diagnostic or therapeutic management in gastroenterological everyday practice.

Connections between vitamin D and psoriasis have been a matter of interest for the past decades, with its active metabolite, 1,25(OH)₂ vitamin D, being valued for antiproliferative and immunomodulatory effects. However, none of vitamin D’s actions could be possible without the CYP27B1 enzyme that bio-activates this metabolite of interest. In order to see if there is any link between the enzyme expression and the disease’s particularities, we conducted a preliminary study that involved 11 skin biopsies of patients with mild (n = 4) or moderate to severe psoriasis (n = 7). The cell proliferation antigen Ki67 and the CD45RO+ marker were also assessed. Compared with healthy skin, in psoriasis, it is reported that the enzyme’s expression seems to be more ubiquitous, but a clear correlation between the disease’s severity and the CYP27B1 expression was, to our knowledge, lacking. We found that, in patients with very mild psoriasis, the enzyme expression was observed in the epidermal stratum basale in a similar manner as in healthy skin specimens. Contrary, for higher severity scores, a divergent result was observed, with the enzyme being either variably spread in the epidermal stratum spinosum or completely absent. Unlike malignant diseases, a significant connection between CYP27B1 and Ki67 (p = 0.313) or CYP27B1 and CD45RO+ (p = 0.657) does not seem to be relevant in psoriasis.

Tuberculosis Peritonitis is a serious condition, whose diagnosis is established late due to the nonspecific nature of the clinical features, which delays the performance of imaging investigations and, implicitly, the setting of the diagnosis through biopsy and histopathological examination. We report the case of a 49-year-old man who presented in our clinic with nonspecific symptoms and significant nitrogen retention, with ascites fluid detected during the clinical–paraclinical examination, ultimately confirming the diagnosis of bacillary peritonitis. Confirmation of tuberculous etiology through biopsy and/or bacteriological examination is sovereign for the diagnosis. The therapeutic protocol includes three anti-tuberculostatic drugs, for a period of at least 6 months, with or without the combination of corticosteroid therapy during the first months of treatment. The patient evolution under treatment was initially favorable, but due to peritoneal adhesions, it underwent complications later.