The Power of Cooperation: A Quantitative Analysis of the Benefit of Civilian Partnerships on the Academic Output of Military Surgeons.

INTRODUCTION: Military-civilian partnerships are crucial to maintaining the skills of active duty surgeons and sustaining readiness. There have been no publications to date that report the quantitative effect of these partnerships on academic research. To address this question, the Hirsch indices (H-indices) of active duty surgeons with a civilian affiliation (CA) were compared to those without. As a secondary outcome, H-indices of military surgeons with and without an appointment to the Uniformed Services University (USU) were similarly compared. We hypothesized that military surgeons with a CA would have a higher H-index as compared to those without. MATERIALS AND METHODS: Rosters of active duty military surgeons were obtained confidentially through each branch consultant. H-indices were found on Scopus. Graduation dates and hospital affiliations were identified via public Doximity, LinkedIn profiles, and hospital biographies. Rosters were cross-referenced with USU appointments. Stata software was used for final analysis. RESULTS: Military surgeons without a civilian association have a median H-index of 2 versus 3 in those with such an affiliation (P = .0002). This pattern is also seen in average number of publications, at 3 and 5 articles (P < .0001). When further stratified by branch, Air Force surgeons have median H-indices of 2.5 and 1 with and without a CA, respectively (P = .0007). The Army surgeons follow a similar pattern, with median H-indices of 5 and 3 for those with and without affiliations, respectively (P = .0021). This significance does not hold in the Naval subgroup. Similar results are found for the secondary outcome of USU appointment, with median H-indices of 3 and 2 in those with and without CAs, respectively (P < .0001). In the multivariable negative binomial regression model, both CA and USU appointment significantly increased H-index in the overall cohort, with incidence rate ratios of 1.32 (95% CI = 1.08, 1.61) and 1.56 (95% CI = 1.28, 1.91), respectively. CONCLUSION: This article provides objective evidence that there is a benefit to military-civilian partnerships on the academic output of military surgeons. These relationships should continue to be fostered and expanded.

Prognostic Role of Lymph Node Sampling in Adolescent and Young Adults With Fibrolamellar Carcinoma.

INTRODUCTION: Hepatocellular carcinoma (HCC) is rare among adolescent and young adult (AYA) patients, and resection or transplant remains the only curative therapy. The role of lymph node (LN) sampling is not well-defined. The aim of this study was to describe practice patterns, as well as investigate the impact of LN sampling on survival outcomes in this population. MATERIALS AND METHODS: A retrospective cohort study using the 2004-2018 National Cancer Database (NCDB) was performed. Patients ≤21 y old with nonmetastatic HCC who underwent liver resection or transplant were evaluated. Clinical features of patients who underwent LN sampling were compared to those who did not, and univariable and multivariable logistic regression was performed to evaluate independent predictive factors of node positivity. Survival analysis was performed using Kaplan-Meier methods and Cox Proportional Hazard Survival Regression. RESULTS: A total of 262 AYA patients with HCC were identified, of whom 137 (52%) underwent LN sampling, 44 patients had positive nodes, 40 (95%) of them had tumors >5 cm; 87 (64%) of patients with sampled nodes had fibrolamellar carcinoma (FLC), which was an independent risk factor for predicting positive nodes (P = 0.001). There was no difference in overall survival between patients who underwent LN sampling and those who did not; however, 5-y overall survival for node-positive patients was 40% versus 79% for node-negative patients (P < 0.0001). CONCLUSIONS: In AYA patients with HCC, LN sampling was not associated with an independent survival benefit. However, FLC was an independent risk factor for LN positivity, suggesting a role for routine LN sampling in these patients.

Addition of neurological status to pediatric adjusted shock index to predict early mortality in trauma: A pediatric Trauma Quality Improvement Program analysis.

INTRODUCTION: Pediatric adjusted shock index (SIPA) has demonstrated the ability to prospectively identify children at the highest risk for early mortality. The addition of neurological status to shock index has shown promise as a reliable triage tool in adult trauma populations. This study sought to assess the utility of combining SIPA with Glasgow Coma Scale (GCS) for predicting early trauma-related outcomes. METHODS: Retrospective review of the 2017 Trauma Quality Improvement Program Database was performed for all severely injured patients younger than 18 years old. Pediatric adjusted shock index and reverse SIPA × GCS (rSIG) were calculated. Age-specific cutoff values were derived for reverse shock index multiplied by GCS (rSIG) and compared with their SIPA counterparts for early mortality assessment using area under the receiver operating characteristic curve analyses. RESULTS: A total of 10,389 pediatric patients with an average age of 11.4 years, 67% male, average Injury Severity Score of 24.1, and 4% sustaining a major penetrating injury were included in the analysis. The overall mortality was 9.3%. Furthermore, 32.1% of patients displayed an elevated SIPA score, while only 27.5% displayed a positive rSIG. On area under the receiver operating characteristic curve analysis, rSIG was found to be superior to SIPA as a predictor for in hospital mortality with values of 0.854 versus 0.628, respectively. CONCLUSION: Reverse shock index multiplied by GCS more readily predicted in hospital mortality for pediatric trauma patients when compared with SIPA. These findings suggest that neurological status should be an important factor during initial patient assessment. Further study to assess the applicability of rSIG for expanded trauma-related outcomes in pediatric trauma is necessary. LEVEL OF EVIDENCE: Prognostic study, level IV.

Dynamic trend or static variable: Shock Index Pediatric-Adjusted (SIPA) in warzone trauma.

BACKGROUND: Civilian studies suggest that trending Shock-Index Pediatric Adjusted(SIPA) values can prove useful in the prediction of trauma outcomes. The purpose of this study was to evaluate the relationship between trends in SIPA and outcomes in pediatric warzone trauma. METHODS: Retrospective review of the Department of Defense Trauma Registry from 2008 to 2015, including all patients age ≤17years. SIPA was calculated both pre-hospital and upon arrival, then classified as "normal" or "abnormal" based upon previously validated thresholds. Patients were stratified into groups based on the trend of their SIPA (1-normal to normal, 2-normal to abnormal, 3-abnormal to normal, 4-abnormal to abnormal). Key outcomes including ICU admission, severe injury, mechanical ventilation, and mortality were then compared between groups. RESULTS: 669 patients were included, mean ISS 12 ± 10. The most common mechanism of injury was blast (46.5%). Overall, 43% were stratified into Group 1, 13.9% into Group 2, 14.8% into Group 3, and 28.0% into Group 4. Those patients with a persistently abnormal SIPA (Group 4) had significantly increased incidence of severe injury, ICU admission, need for mechanical ventilation, and mortality. CONCLUSION: Trends in SIPA may be used to predict trauma outcomes for children injured in warzones, with persistently abnormal values associated with worse outcomes overall.

Pediatric adjusted reverse shock index multiplied by Glasgow Coma Scale as a prospective predictor for mortality in pediatric trauma.

INTRODUCTION: Shock index and its pediatric adjusted derivative (pediatric age-adjusted shock index [SIPA]) have demonstrated utility as prospective predictors of mortality in adult and pediatric trauma populations. Although basic vital signs provide promise as triage tools, factors such as neurologic status on arrival have profound implications for trauma-related outcomes. Recently, the reverse shock index multiplied by Glasgow Coma Scale (GCS) score (rSIG) has been validated in adult trauma as a tool combining early markers of physiology and neurologic function to predict mortality. This study sought to compare the performance characteristics of rSIG against SIPA as a prospective predictor of mortality in pediatric war zone injuries. METHODS: Retrospective review of the Department of Defense Trauma Registry, 2008 to 2016, was performed for all patients younger than 18 years with documented vital signs and GCS on initial arrival to the trauma bay. Optimal age-specific cutoff values were derived for rSIG via the Youden index using receiver operating characteristic analyses. Multivariate logistic regression was performed to validate accuracy in predicting early mortality. RESULTS: A total of 2,007 pediatric patients with a median age range of 7 to 12 years, 79% male, average Injury Severity Score of 11.9, and 62.5% sustaining a penetrating injury were included in the analysis. The overall mortality was 7.1%. A total of 874 (43.5%) and 685 patients (34.1%) had elevated SIPA and pediatric rSIG scores, respectively. After adjusting for demographics, mechanism of injury, initial vital signs, and presenting laboratory values, rSIG (odds ratio, 4.054; p = 0.01) was found to be superior to SIPA (odds ratio, 2.742; p < 0.01) as an independent predictor of early mortality. CONCLUSION: Reverse shock index multiplied by GCS score more accurately identifies pediatric patients at highest risk of death when compared with SIPA alone, following war zone injuries. These findings may help further refine early risk assessments for patient management and resource allocation in constrained settings. Further validation is necessary to determine applicability to the civilian population. LEVEL OF EVIDENCE: Prognostic study, level IV.

Validation of Shock Index Pediatric-Adjusted for children injured in warzones.

BACKGROUND: Shock Index Pediatric-Adjusted (SIPA) has been used to predict injury severity and outcomes after civilian pediatric trauma. We hypothesize that SIPA can predict the need for blood transfusion and emergent surgery among pediatric patients injured in warzones, where resources are limited and accurate triage is essential. METHODS: Retrospective review of the DoD Trauma Registry for all patients 17 years or younger, from 2008 to 2015. Shock Index Pediatric-Adjusted was determined using vital signs recorded upon arrival to the initial level of care. Patients were classified into two groups (normal vs. elevated SIPA) using age-specific threshold values. The need for blood product transfusion (BPT) within 24 hours and emergent surgical procedures (ESP) was compared between groups. Intensive care unit admission, injury severity, and mortality were also compared. Regression analysis was performed to evaluate the relationship between SIPA and primary outcomes. RESULTS: There were 2,121 patients included with a mean Injury Severity Score of 12 ± 10. The mechanism of injury was penetrating (63%), blunt (25%), and burns (12%). Patients with an elevated SIPA (43%) had a significantly greater need for BPT (49.2% vs. 25.0%) and ESP (22.9% vs. 16.0%), as well as mortality (10.3% vs. 4.8%) and intensive care unit admission (49.9% vs. 36.1%), all p less than 0.001. Regression analysis confirmed an elevated SIPA as independently associated with both BPT (odds ratio, 2.36; 95% confidence interval, 1.19-2.94; p < 0.001) and ESP (odds ratio, 1.29; 95% confidence interval, 1.01-1.64; p = 0.044). CONCLUSION: This is the first study of SIPA in pediatric warzone trauma. Elevated SIPA is associated with significantly increased need for BPT and emergent surgery and may therefore serve as a valuable tool for planning and triage in austere settings. LEVEL OF EVIDENCE: Prognostic/epidemiological, Level III.

Predictors of Bowel Resection During Nonelective Ladd Procedure for Pediatric Malrotation.

BACKGROUND: The objective of this study was to identify risk factors for bowel resection in a modern cohort of patients undergoing nonelective Ladd procedures. MATERIALS AND METHODS: Retrospective descriptive analysis of patients with Ladd procedure (CPT 44055) in the National Surgical Quality Improvement Program-Pediatric (NSQIP-P) database (2012-2015). Exclusion criteria were elective case, duodenal atresia, or other known congenital anomaly (except cardiac, structural central nervous system, or airway anomaly) and open wounds from prior surgery or drains. Independent variables included all preoperative variables within NSQIP-P. The primary outcome variable was bowel resection as a concurrent procedure. Multivariate analysis was performed by incorporating all independent variables into a stepwise forward logistic regression model to identify independent risk factors for bowel resection. RESULTS: Of 267,289 patients in NSQIP-P, 1284 had a Ladd procedure. Of these, 292 were performed urgently or emergently in children with no known atresias, congenital anomalies, or open wounds. Twenty-nine (10%) had a bowel resection. On univariate analysis, bowel resection rates did not differ by age, weight, prematurity, ventilator dependence, asthma, chronic lung disease, tracheostomy, esophageal or gastrointestinal disease, hepatobiliary or pancreatic disease, cerebral palsy, central nervous system abnormality, neuromuscular disorder, intraventricular hemorrhage, steroid use, hematologic disorder, malignancy, sepsis, inotropic support, or CPR (P = nonsignificant). Higher rates of bowel resection were observed in patients with cardiac risk factors, white blood count (WBC) >15K, oxygen support, nutritional support, and developmental delay (P < 0.05). Only cardiac risk factors and WBC >15K were significant on multivariate analysis. CONCLUSIONS: Bowel resections (10% in this cohort of nonelective Ladd procedures) were independently associated with cardiac risk factors and WBC >15K. LEVEL OF EVIDENCE: III.

Morbidity and mortality associated with liver resections for primary malignancies in children.

PURPOSE: Liver resection (LR) is a high-risk procedure with limited data in the pediatric surgical literature regarding short-term outcomes. Our aim was to characterize the patient population and short-term outcomes for children undergoing LR for malignancy. METHODS: We studied 126 inpatient admissions for children ≤20 years of age undergoing LR in 2009 using the Kids' Inpatient Database. Patients had a principal diagnosis of a primary hepatic malignancy and LR listed as one of the first five procedures. Transplantations were excluded. Complications were defined by ICD-9 codes. High-volume centers performed at least 5 LR. RESULTS: The mean age was 5.83 years. The morbidity and mortality rates were 30.7 and 3.7%, respectively. The most common causes of morbidity were digestive system complications (7.4%), anemia (7.3%), and respiratory complications (3.8%). 43.9% received a blood product transfusion. The average length of stay was 10.04 days. When compared to low-volume centers, high-volume centers increased the likelihood of a complication fourfold (P = 0.011) but had 0% mortality (P = 0.089). CONCLUSION: LR remains a procedure fraught with multiple complications and a significant mortality rate. High-volume centers have a fourfold increase in likelihood of complications compared to low-volume centers and may be related to extent of hepatic resection.

Obesity has minimal impact on clinical outcomes in children with inflammatory bowel disease.

PURPOSE: Childhood obesity is an increasing problem in affluent societies throughout the world. We sought to identify the impact of obesity on the outcome of inflammatory bowel disease (IBD) and determine differences (if any) between ulcerative colitis (UC) and Crohn's disease (CD). METHODS: The 2009 Kids' Inpatient Database was explored for all children (≤ 20 years) admitted with IBD. ICD-9 codes were used to identify obesity and complications, including hemorrhage, perforation, and complex fistulas. Logistic regression analysis accounting for demographics, underlying disease, surgical procedures, and obesity was performed to identify factors associated with complication development. Data are expressed as odds ratios (OR) and a 95% confidence interval (CI). A P value of 0.05 was regarded as significant. RESULTS: From 12,465 admissions, 164 children were obese (1.3%), with no difference between CD and UC (1.3% vs. 1.4%; P=0.60). Girls had a two-fold increase in obesity (OR: 2.06, CI: 1.48-2.86; P<0.01). Obesity had no effect on elective/emergent admission rate (OR: 0.85, CI: 0.54-1.35; P=0.49), perforation (OR: 0.76, CI: 0.13-4.46; P=0.76), hemorrhage (OR: 0.64,CI: 0.34-1.21; P=0.17), complex fistula (OR: 1.19, CI: 0.45-3.17; P=0.72), or requirement for surgery (OR: 0.80, CI: 0.48-1.31; P=0.37). While the overall clinical morbidity rate was 10.7%, obesity was not associated with the development of overall complications (OR 1.20, CI: 0.75-1.93; P=0.45) or length of stay (6.36 vs. 6.10 days; P=0.61). Obesity increased the rate of central venous catheter (CVC) infections (OR: 10.98, CI: 2.50-48.20; P<0.01). CONCLUSIONS: Obesity was more prevalent in girls with IBD. While obesity did not alter disease severity, rate of surgical intervention, or hospital length of stay, it was associated with higher CVC infections.

The increasing incidence of adolescent bariatric surgery.

BACKGROUND: Morbid obesity continues to be a significant problem within the United States, as overweight/obesity rates are nearing 33%. Bariatric surgery has had success in treating obesity in adults and is becoming a viable treatment option for obese adolescents. METHODS: We studied 1615 inpatient admissions for children ≤20 years of age undergoing a bariatric procedure for morbid obesity in 2009 using the Kids' Inpatient Database (KID). Patients had a principal diagnosis of obesity and a bariatric procedure listed as one of their first 5 procedures. Procedures (open gastric bypass, laparoscopic gastric bypass, sleeve gastrectomy, laparoscopic gastroplasty, and laparoscopic gastric band) and complications were defined by ICD-9 codes. RESULTS: There were 90 open gastric bypasses, 906 laparoscopic gastric bypasses, 150 sleeve gastrectomies, 18 laparoscopic gastroplasties, and 445 laparoscopic gastric bandings. The length of stay for each procedure was 2.44, 2.20, 2.33, 1.10, and 1.02 days, respectively (P<0.001). The complication rates were 3.3%, 3.5%, 0.7%, 0.0%, 0.2%, respectively (P=0.004). CONCLUSIONS: Bariatric surgery is an increasingly utilized option for the treatment of morbid obesity among adolescents. The procedures can be performed safely as evidenced by low complication rates. Additional long-term follow-up is necessary.

Perirectal abscess infections related to MRSA: a prevalent and underrecognized pathogen.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is not a commonly recognized pathogen isolated from perirectal abscesses. Complex perirectal abscesses of MRSA origin may present a significant challenge to the physician and result in treatment failure. The aim of our study was to determine the prevalence of MRSA in our patient population with perirectal abscesses and whether antibiotics coverage, if given, was adequate. METHODS: We conducted a retrospective study of all adult patients who presented with a perirectal abscess. The bacteriology of the cultures taken from more than 100 patients during an 8-year period was examined. The prevalence of MRSA was specifically analyzed, and the sensitivities of the organisms isolated were then compared with any antibiotics prescribed to determine the adequacy of coverage. RESULTS: In all, 124 patients were treated for perirectal abscess during the 8-year period. Fifty-nine percent of patients were taken to the operating room for incision and drainage, 52% of the patients had cultures taken of the abscess, and 35% of patients were given antibiotics coupled with incision and drainage. The antibiotics offered adequate coverage when compared with the sensitivities of the organisms 73% of the time. The prevalence of MRSA in our patient population was 19%, and when this organism was cultured, the patient only received adequate coverage 33% of the time. CONCLUSION: The presence of MRSA in perirectal abscesses is underrecognized. Recent data has shown that incision and drainage combined with antibiotics offers a superior outcome in soft tissue abscesses caused by this organism. If cultures are not routinely taken at the time of incision and drainage, the institutional incidents of MRSA will remain unknown. Physicians must recognize that MRSA is a potential organism present in perirectal abscesses when considering antimicrobial therapy for complex abscesses.

Elective inguinal hernia repair during Operation Iraqi Freedom.

OBJECTIVE: While there have been many publications regarding trauma care in the deployed environment, there is little discussion on the management of the more mundane maladies. This article examines the role of elective surgical intervention for inguinal hernia repairs within theater. Current U.S. policy transports service members out of theater for elective repair and convalescence. In these times of limited man power, this can represent a significant loss of the fighting strength. METHODS: Between January 2006 and July 2006, military surgeons at the 47th Combat Support Hospital in Iraq repaired 11 inguinal hernias. All patients were encouraged to resume normal duty and physical training as soon as possible. A post-procedure questionnaire was completed 6-12 months after surgery. RESULTS: Four repairs were completed with the Prolene Hernia System (PHS; Ethicon, West Somerville, NJ) and seven repairs using the plug and patch method (C. R. Bard, Inc., Murray Hill, NJ). Ten patients were available for follow-up. There were no wound infections, nerve injuries, or recurrences. Patients returned to full duty within 3 days to 6 weeks. CONCLUSIONS: Based on our experience and the feedback from our patients, no complications were noted in this small population of elective hernia repairs. Further prospective trials with long term follow-up are needed to confirm these initial findings.

Survival trends in children with hepatoblastoma.

PURPOSE: Hepatoblastoma (HB) is a relatively rare pediatric malignancy. In this study, we present demographic data and a survival analysis from the largest patient cohort with HB reported to date. METHODS: The surveillance, epidemiology, and end results database was queried from 1973 to 2005 for all patients diagnosed with HB. Kaplan-Meier survival analysis was conducted to determine actuarial survival. Cox regression analysis was performed to determine hazard ratios (HR) for prognostic variables. RESULTS: During the study period, 459 patients with HB were identified. Overall 1-, 3-, and 5-year survival rates for the entire patient cohort were 76, 63, and 60%, respectively. Five-year survival improved over time from 36 (1973-1982) to 63% (1983-2005). Predictors of poor survival include: age 2 years and greater (HR 1.566), black race (HR 1.910), diagnosis prior to 1983 (HR 3.327), inability to perform surgical resection (HR 3.857), regional disease (HR 1.939), and distant disease (HR 3.196). CONCLUSIONS: Hepatoblastoma continues to challenge surgeons and oncologists. Most children are diagnosed early in life and undergo surgical resection whenever possible. With the advent of efficacious chemotherapy, survival has improved. Older children, black patients, and those who present with advanced disease tend to have poor outcomes. Surgical resection is the single most important predictor of survival.

Use of recombinant factor VILa in Operation Iraqi Freedom and Operation Enduring Freedom: survey of Army surgeons.

Military physicians are using recombinant factor VIIa (rFVIIa) in Iraq and Afghanistan to help stop life-threatening hemorrhage in trauma patients. We constructed a questionnaire and surveyed Army general surgeons deployed to Iraq and/or Afghanistan about their predeployment experience, deployment experience, and projected postdeployment practice regarding rFVIIa usage. Most surgeons had rFVIIa available during their deployment (65%). The drug was used with varying frequency and subjective therapeutic effect. A majority of surgeons (79%) were unaware of any guideline or policy governing the use of rFVIIa. Seventy percent of respondents would use the drug in their future practice. Deployed surgeons generally have positive attitudes regarding the use of rFVIIa, but greater guidance and outcome measures are needed.

Abdominal wall endometriosis: a surgeon's perspective and review of 445 cases.

BACKGROUND: Abdominal wall endometriosis (AWE) is defined as endometrial tissue superficial to the peritoneum. AWE often is misdiagnosed and referred to surgeons for treatment. We performed a systematic review of published cohorts to quantify demographics, symptoms, and outcomes of patients having AWE. METHODS: An English language PubMed search from January 1951 to August of 2006 was conducted using several search terms for endometrioma. CONCLUSIONS: Twenty-nine articles describing 455 patients were identified and met inclusion criteria. The pooled mean age was 31.4 years. Ninety-six percent presented with a mass, 87% presented with pain, and 57% presented with cyclic symptoms. AWE was associated with a caesarian scar or hysterectomy in 57% and 11% of cases, respectively. The interval from index surgery to presentation was 3.6 years. Recurrence after resection was 4.3%. The most common presentation of AWE is the development of a painful mass after uterine surgery. Surgical treatment appears to result in a cure more than 95% of the time.

Use of rFVIIa in the trauma setting--practice patterns in United States trauma centers.

Much excitement has been generated regarding the off label use of recombinant factor VIIa (rFVIIa) in the severely injured trauma patient. The purpose of our study is 3-fold: 1) describe the type of centers that use rFVIIa, 2) determine which centers use the drug more frequently, and finally 3) investigate how this drug is being administered at trauma centers. A survey was mailed or e-mailed to 435 trauma centers (Level I and II) throughout the nation. One hundred fifty-six surveys were returned. American College of Surgeons (ACS) verification and trauma Level I designation were independent predictors of rFVIIa use (odds ratio [OR] 3.74 and 5.40, P < 0.05). High users of rFVIIa were defined as those centers that had above median usage of the drug. Level I centers accounted for 67 per cent of the high users. Only the number of fellowship-trained trauma surgeons and trauma volume predicted high usage of rFVIIa (OR 1.38 and 14.09, P < 0.05). Trauma volume predicted whether or not Factor VII users implemented a protocol based approach to administration of the drug (OR 6.57, P < 0.05). Most protocols incorporated packed red blood cells (74%) before giving rFVIIa. The dose of 90 mcg/kg was exceeded in 34 per cent of centers, and 3 per cent used the 200 mcg/kg dose. High volume Level I trauma centers use rFVIIa more frequently and are more likely to use a systematic approach to its administration. However, there is no standardized approach to rFVIIa administration in United States trauma centers.

Presentation and management of Morgagni hernias in adults: a review of 298 cases.

BACKGROUND: Morgagni hernias are a very rare form of diaphragmatic hernias. No robust studies have been performed to show the true natural history of this disease process. This study aimed to summarize clinically relevant data with respect to Morgagni hernias in adults. These data should help surgeons workup, diagnose, and treat Morgagni hernias in adult patients. METHODS: A literature search was performed using PubMed, Google scholar, and the following key words: Morgagni, Larrey, retrosternal, retrocostoxiphal, retrochondrosternal, parasternal, substernal, anterior diaphragmatic, and subcostosternal. All case reports and series after 1951 that pertained to adults were included in the review. The following data points were queried: age, sex, presentation, studies used during workup, laterality, surgical approach, hernia sac management, specific laparoscopic techniques, and follow-up evaluation. RESULTS: These criteria were met by 135 articles representing 298 patients. Based on the data provided, several conclusions regarding this disease process can be drawn. Most patients (72%) present with symptoms related to their hernia. Pulmonary complaints are the most common symptoms (36%). Men present earlier in life than women. Thoracotomy is the most widely used surgical approach (49%). However, laparoscopic repair has gained popularity since its first report in 1992. Laparoscopic surgeons usually repair the defect with mesh (64%) and do not remove the hernia sac (69%). Laparoscopic repair can be performed with a low complication rate (5%) and a short hospital stay (3 days). Outcomes of other surgical approaches also are reported. CONCLUSIONS: Using modern surgical techniques including laparoscopy, repair of Morgagni hernia can be performed safely with a short hospital stay and with little morbidity or mortality.

Budd-Chiari syndrome: illustrated review of current management.

Budd-Chiari syndrome (BCS) is characterized by hepatic venous outflow obstruction at any level from the small hepatic veins to the atriocaval junction. BCS is a complex disease with a wide spectrum of aetiologies and presentations. This article reviews the current literature with respect to presentation, management and prognosis of the disease. Medical, interventional and surgical management of BCS is discussed. Particular attention is paid to interventional and surgical aspects of management. The review is augmented by images, which provide a clinical corollary to the text.

Cloning and characterization of Xenopus beta2-microglobulin.

cDNAs for Xenopus beta2-microglobulin (beta2m), the obligatory light chain of most vertebrate Major Histocompatibility Complex (MHC) class I molecules, were isolated and ESTs were identified. Alignment of the deduced amino acid sequence to other species' beta2m showed that the overall structure is evolutionarily conserved, and phylogenetic analysis showed that the Xenopus beta2m sequence is intermediate between fish and bird/mammal beta2m. The Xenopus beta2m mRNA is expressed ubiquitously with highest expression in intestine, spleen, and thymus, correlating well with classical class Ia expression. beta2m mRNA and protein were also detected in Xenopus thymic tumor and kidney cell lines. Segregation analysis on a tetraploid Xenopus laevis family revealed two independently segregating, non-MHC-linked loci. As expected, only one locus was found in the diploid Xenopus tropicalis, strongly suggesting that the two beta2m loci in the tetraploid species were generated by genome-wide duplication, and did not undergo diploidization unlike many other MHC genes.

Ontogeny of Xenopus NK cells in the absence of MHC class I antigens.

This paper explores the ontogeny of NK cells in control and early-thymectomized (Tx) Xenopus laevis through phenotypic analysis of cells expressing the NK cell antigen 1F8 and by performing in vitro cytotoxic assays. Dual color flow cytometry reveals that a few 1F8positive splenocytes first emerge in late larval life, at approximately 7-weeks post-fertilization. This is about 2-weeks after the time when surface MHC class Ia expression can first be detected. The proportion of splenocytes expressing 1F8 remains very low in 3-4 month-old froglets, but by 1 year there is a sizeable 1F8positive population, which is proportionally elevated in Tx frogs. The ontogeny of NK cell function is monitored by a 5 h DNA fragmentation (JAM) assay. Control and Tx larval splenocytes (from either 5- or 7-week-old tadpoles) fail to kill MHC-deficient thymus-derived tumor cell targets. Such in vitro killing is still relatively poor in 3-4 month froglets, compared with high levels of tumor cell cytotoxicity mediated by splenocytes from older frogs. Immunoprecipitation studies identify that the major ligand for the 1F8 mAb is a 55 kDa polypeptide. Finally, further evidence is provided that 1F8positive lymphocytes are indeed bona fide NK cells, distinct from T cells, since purified 1F8positive splenocytes from Tx Xenopus fail to express fully rearranged TCRbeta V region transcripts. We conclude that NK cells fail to develop prior to MHC class I protein expression and, therefore, do not contribute to the larval immune system, whereas they do provide an important backup for T cells in the adult frog by contributing to anti-tumor immunity.