Giant Pancreatic Myoepithelial Hamartoma in a Patient With Familial Insulin-Dependent Diabetes Mellitus.

ABSTRACT: Pancreatic myoepithelial hamartoma is a rare, benign solid and cystic lesion of the pancreas. We present the first case of an adult with a giant myoepithelial hamartoma extending throughout the pancreas in a patient with diabetes in 4 immediate family members. The patient is a 46-year-old man presented with recurrent acute pancreatitis. Computed tomographic imaging showed that the head and body of the pancreas were replaced by a solid-cystic mass with focal calcification. Medical history includes insulin-dependent diabetes mellitus (IDDM) diagnosed at age 30. Endoscopic ultrasound-guided fine-needle aspiration showed pancreatic acinar tissue and smooth muscle without evidence of malignancy. Total pancreatectomy was performed because of the diffuse nature of the cystic disease and preexisting IDDM. The histopathologic diagnosis was consistent with myoepithelial hamartoma. In addition, there was a family history of IDDM and hamartomatous cyst resection in the paternal grandmother. We report the first case of diffuse pancreatic myoepithelial hamartoma with near total replacement of the entire pancreatic parenchyma, and the first reported case associated with a family history of heritable IDDM. Improved knowledge of the genetics, development, and malignant potential of such rare diseases is critical to determine appropriate management for patients.

Duct of Luschka Bile Leak Following Deceased Donor Liver Transplant.

BACKGROUND Biliary leak is a relatively uncommon but potentially severe complication of liver transplantation. Duct of Luschka (also known as subvesical bile ducts) is a term that refers to a number of accessory biliary ducts. While leaks from Ducts of Luschka are well-described in the field of hepatobiliary surgery, only 2 case reports of such leaks exist in the setting of liver transplant. CASE REPORT We report the first case of a Duct of Luschka biliary leak seen after DCD liver transplant in a 41-year-old woman with cirrhosis secondary to primary sclerosing cholangitis. The patient underwent surgical re-exploration in the immediate postoperative period due to bilious output from a surgical drain. A Duct of Luschka was found intraoperatively at the gallbladder fossa and was oversewn. Apart from immunosuppression-related neutropenia, the patient recovered uneventfully. CONCLUSIONS Given the variability in preoperative detection of subvesical bile ducts, accessory bile duct leak remains an important consideration in the liver transplant perioperative period. The prevalence of Ducts of Luschka and the relative risk of leakage from such subvesical bile ducts in liver transplants compared to cholecystectomies are unclear. Further research into anatomical accessory bile duct variants and preoperative techniques for detecting such ducts is warranted.

Cellular Therapies in Solid Organ Allotransplantation: Promise and Pitfalls.

Donor specific transfusions have been the basis of tolerance inducing protocols since Peter Medawar showed that it was experimentally feasible in the 1950s. Though trials of cellular therapies have become increasingly common in solid organ transplantation, they have not become standard practice. Additionally, whereas some protocols have focused on cellular therapies as a method for donor antigen delivery-thought to promote tolerance in and of itself in the correct immunologic context-other approaches have alternatively focused on the intrinsic immunosuppressive properties of the certain cell types with less emphasis on their origin, including mesenchymal stem cells, regulatory T cells, and regulatory dendritic cells. Regardless of intent, all cellular therapies must contend with the potential that introducing donor antigen in a new context will lead to sensitization. In this review, we focus on the variety of cellular therapies that have been applied in human trials and non-human primate models, describe their efficacy, highlight data regarding their potential for sensitization, and discuss opportunities for cellular therapies within our current understanding of the immune landscape.

Spontaneous Ureterocolic Fistula between Nonfunctioning Kidney Transplant Ureter and Colon in Setting of Diverticulitis.

Ureterocolic fistula is a rare condition that most commonly occurs in the setting of diverticular disease. The development of a ureterocolic fistula following kidney transplantation is even rarer, with no prior cases in the literature to our knowledge. We describe the case of a patient with three prior failed kidney transplants who developed a fistula between the sigmoid colon and nonfunctioning renal transplant ureter in the setting of diverticulitis.

Silica Exposure Differentially Modulates Autoimmunity in Lupus Strains and Autoantibody Transgenic Mice.

Inhalational exposure to crystalline silica is linked to several debilitating systemic autoimmune diseases characterized by a prominent humoral immune component, but the mechanisms by which silica induces autoantibodies is poorly understood. To better understand how silica lung exposure breaks B cell tolerance and unleashes autoreactive B cells, we exposed both wildtype mice of healthy C57BL/6 and lupus-prone BXSB, MRL, and NZB strains and mice carrying an autoantibody transgene on each of these backgrounds to instilled silica or vehicle and monitored lung injury, autoimmunity, and B cell fate. Silica exposure induced lung damage and pulmonary lymphoid aggregates in all strains, including in genetically diverse backgrounds and in autoantibody transgenic models. In wildtype mice strain differences were observed in specificity of autoantibodies and site of enhanced autoantibody production, consistent with genetic modulation of the autoimmune response to silica. The unique autoantibody transgene reporter system permitted the in vivo fate of autoreactive B cells and tolerance mechanisms to be tracked directly, and demonstrated the presence of transgenic B cells and antibody in pulmonary lymphoid aggregates and bronchoalveolar lavage fluid, respectively, as well as in spleen and serum. Nonetheless, B cell enumeration and transgenic antibody quantitation indicated that B cell deletion and anergy were intact in the different genetic backgrounds. Thus, silica exposure sufficient to induce substantial lung immunopathology did not overtly disrupt central B cell tolerance, even when superimposed on autoimmune genetic susceptibility. This suggests that silica exposure subverts tolerance at alternative checkpoints, such as regulatory cells or follicle entry, or requires additional interactions or co-exposures to induce loss of tolerance. This possibility is supported by results of differentiation assays that demonstrated transgenic autoantibodies in supernatants of Toll-like receptor (TLR)7/TLR9-stimulated splenocytes harvested from silica-exposed, but not vehicle-exposed, C57BL/6 mice. This suggests that lung injury induced by silica exposure has systemic effects that subtly alter autoreactive B cell regulation, possibly modulating B cell anergy, and that can be unmasked by superimposed exposure to TLR ligands or other immunostimulants.