Citations

Purpose of review Biphasic anaphylaxis is a well documented complication of anaphylaxis, but it has been inconsistently defined in the literature. Analysis of contemporary studies of biphasic anaphylaxis based on modern definitions is needed. Recent findings The rate of biphasic reactions in contemporary literature ranges from 0.4 to 14.7% depending on the study population. Observational studies have reported risk factors associated with the development of biphasic reactions; however, findings have been inconsistent and of questionable generalizability. Although life-threatening biphasic reactions are rare, up to 50% of biphasic reactions will require treatment with epinephrine. Early epinephrine administration may have a role in prevention of biphasic reactions, but the role of steroids needs further investigation. The optimal duration of observation is yet to be determined. Summary Given the relative rarity of life-threatening biphasic anaphylaxis and the new context of the NIAID/FAAN standardized definition, further research regarding biphasic anaphylaxis is needed to better elucidate the care model for anaphylaxis patients with a focus on: prevention of biphasic reactions; identification of patients at increased risk of a biphasic reaction; determination of appropriate observation strategies for anaphylaxis patients; and patient education and preparation for management of potential biphasic reactions.

Neuromuscular choristoma (NMC) is a very rare, developmental malformation characterized by the endoneurial intercalation of mature muscle fibers among peripheral nerve fibers. NMC typically arises in the major proximal peripheral nerves, most commonly the sciatic nerve, and may involve the lumbosacral and brachial plexus. Patients present clinically with progressive neuropathy or plexopathy. NMC is strongly associated with development of a fibromatosis, histologically identical to conventional desmoid-type fibromatosis (NMC-fibromatosis). The development of NMC-fibromatosis is often precipitated by iatrogenic trauma (ie, biopsy). Desmoid-type fibromatosis is characterized by CTNNB1 exon 3 mutations, which result in aberrant nuclear β-catenin localization and dysregulated canonical Wnt signaling. In contrast, the pathogenesis of NMC and NMC-fibromatosis is unknown. Desmoid-type fibromatosis expresses estrogen receptors (ER), specifically the ER-beta isoform (ERβ), and endocrine therapies may be used in surgically unresectable cases. In contrast, the ER expression profile of NMC-fibromatosis is unknown. We evaluated a series of NMC and NMC-fibromatosis for CTNNB1 mutations, β-catenin expression, and ER isoform expression. Five NMCs occurred in 2 female and 3 male patients (median age: 14 y, range <1 to 42 y), as masses involving the sciatic nerve (N=4) or brachial plexus (N=1). Four (of 5) NMCs had CTNNB1 mutations: 3 c.134 C>T (p.S45F) and 1 c.121 A>G (p.T41A). Four patients subsequently developed NMC-fibromatosis, and all 4 cases contained CTNNB1 mutations, including 1 p.T41A and 3 p.S45F mutations. In 3 patients, the NMC and NMC-fibromatosis had identical CTNNB1 mutations. Only 1 NMC had no detectable CTNNB1 mutation; however, the patient’s subsequent NMC-fibromatosis had a CTNNB1 p.T41A mutation. All NMC and NMC-fibromatosis showed aberrant nuclear localization of β-catenin, nuclear ERβ expression, and no ERα expression. The presence of CTNNB1 mutations both in NMC and NMC-fibromatosis may be a shared molecular genetic abnormality underlying their pathogenesis.

AbstractBackgroundDefecatory disorders (DD) are defined by clinical and objective features of impaired rectal evacuation. The epidemiology of DD in the population is unknown, partly because many constipated patients do not undergo anorectal tests. Our objectives were to estimate the incidence rate and clinical features of DD in the community.MethodsWe reviewed the medical records of all patients older than 16 years in Olmsted County, MN, who had constipation and underwent anorectal manometry from 1999 through 2008. Criteria for diagnosing DD were constipation for 6 months or longer and one of the following: (i) abnormal rectal balloon expulsion test; (ii) reduced or increased perineal descent; or (iii) two or more abnormal features with defecography or surface electromyography.Key ResultsOf 11 112 constipated patients, 516 had undergone anorectal tests; 245 of these (209 women, 36 men) had a DD. The mean (±SD) age at diagnosis was 44 years (±18) among women and 49 years (±19) among men. The overall age‐ and sex‐adjusted incidence rate per 100 000 person‐years was 19.3 (95% CI: 16.8–21.8). The age‐adjusted incidence per 100 000 person‐years was greater (p < 0.0001) in women (31.8, 95% CI: 27.4–36.1) than in men (6.6, 95% CI: 4.4–8.9). Prior to the diagnosis of DD, nearly 30% of patients had irritable bowel syndrome (IBS), 48% had a psychiatric diagnosis, 18% had a history of abuse, and 21% reported urinary and/or fecal incontinence.Conclusions & InferencesAmong constipated patients, DD are fourfold more common in women than men and often associated with IBS and psychiatric diagnoses.

Abstract Background Resection with curative intent has been shown to prolong survival of patients with locoregional pancreatic ductal adenocarcinoma (PDAC). However, up to 33 per cent of patients are deemed unresectable at exploratory laparotomy owing to unanticipated locally advanced or metastatic disease. In these patients, prophylactic double bypass (PDB) procedures have been considered the standard of care. The aim of this study was to compare PDB with exploratory laparotomy alone in terms of impact on postoperative course, chemotherapy and overall survival. Methods This retrospective observational cohort study (2004–2013) was conducted using a prospective institutional database. Patients with histologically confirmed, unresectable PDAC were included. Relationships between PDB procedures, exploratory laparotomy alone, postoperative chemotherapy and best supportive care were investigated by means of Cox regression. Overall survival was compared using Kaplan–Meier estimations and log rank test. Results Of 503 patients with PDAC scheduled for resection with curative intent, 104 were deemed unresectable at laparotomy (resection rate 79·3 per cent). Seventy-four patients underwent PDB procedures and 30 had exploratory laparotomy alone. PDB and exploratory laparotomy were similar in terms of perioperative mortality, initiation of chemotherapy and overall survival. Compared with best supportive care, postoperative chemotherapy prolonged survival (8·0 versus 14·4 months in locally advanced PDAC, P = 0·007; 2·3 versus 8·0 months in metastatic PDAC, P &lt; 0·001). Patients undergoing chemotherapy following exploratory laparotomy alone had longer median overall survival than patients undergoing chemotherapy following PDB procedures (16·3 versus 10·3 months; P = 0·040). Conclusion Patients with pancreatic cancer deemed unresectable at laparotomy may derive survival benefit from subsequent chemotherapy as opposed to supportive care alone. At laparotomy, proceeding with a bypass procedure for prophylactic symptom control may be prognostically unfavourable.

Educators, policy makers, and health systems leaders are calling for significant reform of undergraduate medical education (UME) and graduate medical education (GME) programs to meet the evolving needs of the health care system. Nationally, several schools have initiated innovative curricula in both classroom and workplace learning experiences to promote education in health systems science (HSS), which includes topics such as value-based care, health system improvement, and population and public health. However, the successful implementation of HSS curricula across schools is challenged by issues of curriculum design, assessment, culture, and accreditation, among others. In this report of a working conference using thematic analysis of workshop recommendations and experiences from 11 U.S. medical schools, the authors describe seven priority areas for the successful integration and sustainment of HSS in educational programs, and associated challenges and potential solutions. In 2015, following regular HSS workgroup phone calls and an Accelerating Change in Medical Education consortium-wide meeting, the authors identified the priority areas: partner with licensing, certifying, and accrediting bodies; develop comprehensive, standardized, and integrated curricula; develop, standardize, and align assessments; improve the UME to GME transition; enhance teachers’ knowledge and skills, and incentives for teachers; demonstrate value added to the health system; and address the hidden curriculum. These priority areas and their potential solutions can be used by individual schools and HSS education collaboratives to further outline and delineate the steps needed to create, deliver, study, and sustain effective HSS curricula with an eye toward integration with the basic and clinical sciences curricula.