Co-infections in Persons with Early Lyme Disease, New York, USA.

In certain regions of New York state, USA, Ixodes scapularis ticks can potentially transmit 4 pathogens in addition to Borrelia burgdorferi: Anaplasma phagocytophilum, Babesia microti, Borrelia miyamotoi, and the deer tick virus subtype of Powassan virus. In a prospective study, we systematically evaluated 52 adult patients with erythema migrans, the most common clinical manifestation of B. burgdorferi infection (Lyme disease), who had not received treatment for Lyme disease. We used serologic testing to evaluate these patients for evidence of co-infection with any of the 4 other tickborne pathogens. Evidence of co-infection was found for B. microti only; 4-6 patients were co-infected with Babesia microti. Nearly 90% of the patients evaluated had no evidence of co-infection. Our finding of B. microti co-infection documents the increasing clinical relevance of this emerging infection.

PCSK2 can be Useful in a Panel Approach to Distinguish Foregut and Midgut Neuroendocrine Tumors.

A number of immunohistochemical stains have been examined for utility in establishing the site of origin for metastatic well-differentiated neuroendocrine tumors (NETs). In the gastrointestinal (GI) tract, distinguishing metastatic duodenal NETs from jejunoileal and other GI NETs is important for clinical work-up, prognosis, and therapy. A recent study indicated that prohormone convertase 2 (PCSK2 or PC2) had broad expression in small intestine and appendiceal NETs. Because the study did not include duodenal NETs, we examined PCSK2 expression in duodenal and other GI NETs.GI NETs (n = 69) and 13 corresponding lymph node metastases from stomach, duodenum, pancreas, ileum, appendix, and rectum were evaluated for the expression of PCSK2, along with ISL1, NKX2.2, CDX2, SATB2, and PAX8. Expression of each stain was evaluated using the H-score system, and differences in expression by site were evaluated by the chi square test.PCSK2 was expressed at similar frequency in duodenal (50%), pancreatic (59%), and ileal NETs (40%). PCSK2 was infrequently expressed in stomach (0%), appendiceal (8%), and rectal (25%) NETs. However, incorporating PCSK2 into a panel including ISL1, NKX2.2, CDX2, and SATB2 allowed development of an algorithm which had 87% sensitivity and 93% specificity for classification of ileal NETs; and 68% sensitivity and 98% specificity for pancreaticoduodenal NETs.In contrast to previous findings, PCSK2 does not show specificity for any particular GI site. An algorithmic approach incorporating the expression of PCSK2 with that of ISL1, NKX2.2, CDX2, and SATB2 is useful in discriminating pancreatic, duodenal, ileal, appendiceal, and rectal NETs.

Hidden treasures: Incidental findings in two cases of chronic subdural hematoma.

Background: Extramedullary hematopoiesis (EMH) and plasmacytomas occurring within the cranium are rare entities. Case Description: We review two cases in which patients presented with subdural hematoma and underwent evacuation. On routine histopathologic examination of their membranes, both patients were subsequently found to have focal EMH, as well as a clonal plasma cell proliferation in one case. Conclusion: EMH is rare and usually found in individuals with profound and chronic anemia. However, this entity may be more common in chronic subdural hematomas. Solitary extraosseous plasmacytoma is exceedingly rare in the cranium, and its presence in chronic subdural hematoma membranes is of uncertain significance. The cytokine milieu that promotes organization of chronic subdural hematomas may play a role in the establishment of both of entities in this location.

Primary Angiosarcoma of the Adrenal Gland: Report of 2 Cases and Review of the Literature.

Primary adrenal angiosarcoma is a rare, malignant, vascular neoplasm. These neoplasms typically arise in middle age (median age of 60 years) and are more common in males (65%) than in females. Although rare, these neoplasms are aggressive with a propensity for local recurrence and metastasis and a median survival of 18 months. We present 2 cases of primary adrenal angiosarcoma with synchronous, ipsilateral adrenocortical adenomas. We review the cases of adrenal angiosarcoma reported since 1988 and discuss their clinical and histopathologic characteristics.

Whole exome sequencing of a gut-associated lymphoid tissue neoplasm points to precursor or early form of sporadic colon carcinoma.

Gut-associated lymphoid tissue (GALT) carcinoma is a colorectal neoplasm characterized by cystically dilated neoplastic glands that extend into prominent, well-circumscribed submucosal lymphoid tissue. Although often subtle, lamina propria between and around the neoplastic glands (identified by plasma cells, scattered eosinophils, etc.) is frequent in cases with classic morphology, arguing (at least in such cases) in favor of adenoma extending into lymphoglandular complexes rather than true invasive carcinoma. Some have postulated that the tumor arises from M-cells, specialized epithelial cells overlying GALT, and others have suggested it represents a unique pathway to carcinoma, specific to the environmental conditions of epithelium overlying lymphoid tissue. Although both hypotheses are intriguing, definitive phenotypic and genetic support is currently lacking. To address these possibilities, we undertook whole exome sequencing and immunohistochemical characterization of a GALT neoplasm recently identified on our clinical service. We discovered well-known mutations in both APC and KRAS, as well as mutations in several Wnt pathway components (MED12, BCL9L, RFX4, DACT3). No immunohistochemical expression of GP2, a marker of M-cell differentiation, was identified. Expression of CDX2, SATB2, and the DNA mismatch repair proteins was observed, while expression of both CK7 and CK20 was absent. No PD-L1 expression was present on tumor cells, but PD-L1 expression was noted in a subset of tumor-adjacent mononuclear cells. Overall, the findings suggest that GALT neoplasms, although morphologically distinct, may be a precursor or early form of typical sporadic colon carcinoma.