GI tract CVID displays a wide spectrum of histologic patterns. Its features can mimic lymphocytic colitis, collagenous enterocolitis, celiac disease, lymphocytic gastritis, granulomatous disease, acute graft-versus-host disease, and inflammatory bowel disease. In fact, in our series, we found patients with a prior diagnosis of celiac disease (25%) and inflammatory bowel disease (35%), including Crohn disease (15%). The diagnosis of CVID may be suspected on the basis of the lack of plasma cells in a GI biopsy, but because this feature is only present in about two-thirds of patients, the diagnosis cannot always be suggested in isolation of other clinical and laboratory findings.

No abstract

YAP expression in the cytoplasm and nucleus is significantly increased in high-grade dysplasia and adenocarcinoma of the esophagus as well as gastric adenocarcinoma and metastatic gastric disease, suggesting a role for this recently uncovered pathway in esophageal and gastric epithelial tumorigenesis.

Background Autism spectrum disorder (ASD) involves complex genetics interacting with the perinatal environment, complicating the discovery of common genetic risk. The epigenetic layer of DNA methylation shows dynamic developmental changes and molecular memory of in utero experiences, particularly in placenta, a fetal tissue discarded at birth. However, current array-based methods to identify novel ASD risk genes lack coverage of the most structurally and epigenetically variable regions of the human genome. Results We use whole genome bisulfite sequencing in placenta samples from prospective ASD studies to discover a previously uncharacterized ASD risk gene, LOC105373085, renamed NHIP. Out of 134 differentially methylated regions associated with ASD in placental samples, a cluster at 22q13.33 corresponds to a 118-kb hypomethylated block that replicates in two additional cohorts. Within this locus, NHIP is functionally characterized as a nuclear peptide-encoding transcript with high expression in brain, and increased expression following neuronal differentiation or hypoxia, but decreased expression in ASD placenta and brain. NHIP overexpression increases cellular proliferation and alters expression of genes regulating synapses and neurogenesis, overlapping significantly with known ASD risk genes and NHIP-associated genes in ASD brain. A common structural variant disrupting the proximity of NHIP to a fetal brain enhancer is associated with NHIP expression and methylation levels and ASD risk, demonstrating a common genetic influence. Conclusions Together, these results identify and initially characterize a novel environmentally responsive ASD risk gene relevant to brain development in a hitherto under-characterized region of the human genome.

Molecular analyses of neoplasms of the pancreas, coupled with careful histopathologic examination has helped refine the classification of pancreatic neoplasia. A number of molecularly and histologically distinct subtypes of pancreatic neoplasms have been identified and, importantly, many of these subtypes have important clinical implications. For example, most of the solid-pseudopapillary neoplasms harbor mutations in the beta-catenin gene (CTNNB1), and, as a result, most solid-pseudopapillary neoplasms have an abnormal nuclear pattern of labeling with antibodies to the beta-catenin protein. Clinically, patients with a solid-pseudopapillary neoplasm have a much better prognosis than do patients with ductal adenocarcinoma of the pancreas. Therefore, the immunolabeling of a pancreatic biopsy for the beta-catenin protein can help identify patients with low-risk neoplasms. It is clear that the time is now ripe for a new modern classification of neoplasms of the pancreas; a classification that does not abandon gross and microscopic pathology, but which instead integrates molecular findings with gross, microscopic, and clinical findings.

Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease characterized by inflammatory destruction of the intrahepatic bile ducts. The differential diagnosis for PBC often includes autoimmune hepatitis (AIH). Both diseases can show prominent plasma cells and other overlapping histologic features. It is interesting that both diseases can involve elevated levels of serum immunoglobulins, with IgM elevations typical of PBC and IgG elevations typical of AIH. We investigated whether this difference could be useful histologically by immunostaining plasma cells in liver biopsy specimens for IgG and IgM. We examined 56 cases: 18 of PBC and 38 of AIH. In PBC, plasma cells in the portal tracts were predominantly IgM+, whereas in AIH, plasma cells were predominately IgG+ (P < .0001). Immunostaining for IgM and IgG can be helpful in differentiating PBC from AIH.

In contrast to colchicine-associated changes in non-neoplastic mucosa, the mitotic arrest mimicking HGD seen in GI tract specimens after taxane administration is not specific for toxicity, but may also reflect taxane effect. It can be encountered in asymptomatic patients who have recently had medication. If these findings are seen histologically, they merit correlation with the clinical impression, and should not be interpreted as toxicity in isolation.

No abstract