Acute appendicitis: transcript profiling of blood identifies promising biomarkers and potential underlying processes

Background The diagnosis of acute appendicitis can be surprisingly difficult without computed tomography, which carries significant radiation exposure. Circulating blood cells may carry informative changes in their RNA expression profile that would signal internal infection or inflammation of the appendix. Methods Genome-wide expression profiling was applied to whole blood RNA of acute appendicitis patients versus patients with other abdominal disorders, in order to identify biomarkers of appendicitis. From a large cohort of emergency patients, a discovery set of patients with surgically confirmed appendicitis, or abdominal pain from other causes, was identified. RNA from whole blood was profiled by microarrays, and RNA levels were filtered by a combined fold-change (\u3e2) and p value (\u3c0.05). A separate set of patients, including patients with respiratory infections, was used to validate a partial least squares discriminant (PLSD) prediction model. Results Transcript profiling identified 37 differentially expressed genes (DEG) in appendicitis versus abdominal pain patients. The DEG list contained 3 major ontologies: infection-related, inflammation-related, and ribosomal processing. Appendicitis patients had lower level of neutrophil defensin mRNA (DEFA1,3), but higher levels of alkaline phosphatase (ALPL) and interleukin-8 receptor-ß (CXCR2/IL8RB), which was confirmed in a larger cohort of 60 patients using droplet digital PCR (ddPCR). Conclusions Patients with acute appendicitis have detectable changes in the mRNA expression levels of factors related to neutrophil innate defense systems. The low defensin mRNA levels suggest that appendicitis patient’s immune cells are not directly activated by pathogens, but are primed by diffusible factors in the microenvironment of the infection. The detected biomarkers are consistent with prior evidence that biofilm-forming bacteria in the appendix may be an important factor in appendicitis

Surgical Education and Training in the US: a Collaborative Effort to Deliver the Next Generation of Surgeons.

The foundational principles of surgical training in the USA are based on didactic education, structured skill training, and experiential learning in surgical patient care with the supervision of surgical faculty. A consortium of professional organizations, academic institutions, and teaching hospitals with surgical faculty provide the structural framework, policies, and curriculum to train and evaluate surgeons capable of independent practice. This manuscript describes the roles of the organizations responsible for surgical training in the USA and highlights areas in evolution in the modern surgical education landscape

Laparoscopic versus single-incision cholecystectomy

Background: Although recent reports demonstrate large series of single-incision cholecystectomies, few articles compare single-incision data with traditional laparoscopic cholecystectomy (LC) data. This article compares a large series of single-incision cholecystectomies to a series of traditional LCs performed at an urban tertiary-care center. Methods: A consecutive series of single-incision cholecystectomies was performed from August 2008 to March 2010. All cholecystectomies were attempted through a single incision on an intent-to-treat basis. Patient demographics, including height, weight, body mass index (BMI), pathologic diagnosis, ASA classification, operative time, complications, narcotic use, and length of stay (LOS), were recorded. Data for a matched cohort of patients undergoing a traditional four-port LC were gathered over a similar time period. Data were compared using a t test with a P \u3c 0.05 for significance. Results: Single-incision cholecystectomy was successful in 81 (76%) of 107 patients. The 26 (24%) converted cases showed a higher BMI (33.0 ± 8.7 vs. 28.4 ± 6.4 kg/m2, P \u3c 0.05) and longer operative times (98.3 ± 33 vs. 76.1 ± 23 min, P \u3c 0.003). Postoperatively, the converted patients had a longer LOS compared to that of the single-incision group (1.6 ± 1.0 vs. 1.1 ± 0.4 days, P = 0.02). Overall, the single-incision group had longer operative times compared to the four-port LC group (81.5 ± 28 vs. 69.1 ± 21 min, P \u3c 0.004). However, after the tenth single-incision case, there was no difference in operative times. From a narcotic standpoint, the successful single-incision patients used significantly less narcotic versus the traditional LC group (20 ± 22.7 vs. 32.3 ± 31.2 mg, P = 0.02). Conclusions: The data suggests that individuals with a BMI over 33 may not be candidates for single-incision cholecystectomy. Those patients that undergo a successful single-incision laparoscopic cholecystectomy require fewer narcotics postoperatively and have a shorter LOS. Although this data is intriguing, the overall utility of single-incision procedures requires more analysis and potentially randomized trials. © 2011 Société Internationale de Chirurgie