The (absence of a) role of venous duplex scan in the diagnosis of pulmonary embolism after severe trauma

Venous duplex scan (VDS) has been used for interim bedside diagnosis of pulmonary embolism (PE) in severely injured patients deemed to be at risk if transported out of the intensive care unit. In combination with the level of clinical suspicion for PE, VDS helps select patients for temporary treatment until definitive diagnosis is made. We evaluate the sensitivity and specificity of VDS in critically injured patients with a high level of clinical suspicion for PE. We performed a prospective observational cohort study at the surgical intensive care unit of an academic level 1 trauma center. Patients were 59 critically injured patients suspected to have PE over a 30-month period. The level of clinical suspicion for PE was classified as low or high according to preset criteria. Interventions were VDS and a PE outcome test (conventional or computed tomographic pulmonary angiography). The sensitivity and specificity of VDS to detect PE in all patients and in patients with high level of clinical suspicion was calculated against the results of the outcome test. PE was diagnosed in 21 patients (35.5%). The sensitivity and specificity of VDS was 33 per cent and 89 per cent, respectively. Among the 28 patients who had a high level of clinical suspicion for PE, the sensitivity of VDS was 23 per cent and the specificity 93 per cent. In this latter population, 1 of the 4 (25%) positive VDS was of a patient without PE and 10 of the 24 (42%) negative VDS were of patients who had PE. VDS does not accurately predict PE in severely injured patients, even in the presence of a high level of clinical suspicion.     

A urinary microRNA (miR) signature for diagnosis of bladder cancer

Introduction

Bladder cancer (BC) is diagnosed by cystoscopy, which is invasive, costly and causes considerable patient discomfort. MicroRNAs (miR) are dysregulated in BC and may serve as non-invasive urine markers for primary diagnostics and monitoring. The purpose of this study was to identify a urinary miR signature that predicts the presence of BC.

The adrenal response after severe trauma

BACKGROUND: The integrity of the hypothalamic-pituitary-adrenal axis is a major determinant of the host response to stress. Relative adrenal insufficiency has been implicated in poor outcome from systemic inflammatory states; however, whether low endogenous glucocorticoid levels are adaptive or pathologic remains controversial. The purpose of this study was to prospectively evaluate the cortisol response and determine the incidence of occult adrenal insufficiency after severe trauma. METHODS: Over an 18-month period, 22 severely injured patients admitted to the surgical intensive care unit of our level 1 trauma center were prospectively identified and followed. Demographic and outcome data were tabulated. In addition, random serum cortisol levels were obtained on days 0, 5, and 10 after injury. Relative adrenal insufficiency was defined as a random serum cortisol level less than 18 microg/dL. RESULTS: Mean baseline cortisol levels were elevated (35 +/- 3 microg/dL) and significantly declined over the next 10 days (day 5: 24 +/- 2 microg/dL; and day 10: 22 +/- 2 microg/dL; P <0.01). Thirteen of 22 (60%) patients had random serum cortisol levels less than 18 microg/dL. Only 1 of the 2 patients who died had a serum cortisol level less than 18 microg/dL. The mean cortisol levels at baseline were higher in the 2 patients who died compared with those who survived but this was not statistically significant (43.4 +/- 8.8 microg/dL versus 35.0 +/- 3.6 microg/dL, P = 0.5). CONCLUSIONS: Serum cortisol levels increased immediately and gradually returned towards normal after severe trauma. Occult adrenal insufficiency was common (60%) in this small group of severely injured patients. This did not, however, affect mortality in these patients. Further study is needed to delineate the role of occult adrenal insufficiency after severe injury.     

Neutropenic enterocolitis (typhlitis) after pediatric bone marrow transplant

Background/Purpose: Neutropenic enterocolitis (typhlitis) is a common consideration after bone marrow transplantation. This study reviews the authors' experience with abdominal pain and typhlitis in an active pediatric bone marrow transplant program. Methods: The Pediatric Bone Marrow Transplant Program Database was reviewed for patients presenting with abdominal pain or typhlitis. Results: From 1993 to 2000 a total of 142 transplants have been performed. Of these, 97 patients had abdominal pain, and 5 had radiologically proven typhlitis. Nonspecific abdominal pain developed on the 12 [plusmn] 11th day posttransplant, whereas patients in whom typhlitis developed were diagnosed on day 15.5 [plusmn] 7. All patients were treated with prophylactic antibiotics consisting of acyclovir, fluconazole, and septra. With the onset of abdominal pain, 73 of 97 patients were placed on therapeutic antibiotics; patients identified with typhlitis had amphotericin plus GCSF added. No clinical features differentiated abdominal pain patients from typhlitis. Oral feeding and time of discharge was similar in both groups. Surgical intervention was not required, and no patients died with typhlitis. Conclusions: Abdominal pain is a common symptom after bone marrow transplant; however, typhlitis is relatively rare, and surgical intervention was not required in this series. Broad-spectrum (including fungal) antibiotic therapy appears to be an effective treatment for typhlitis in this patient population.     

Monocyte dysfunction in severe trauma: evidence for the role of C5a in deactivation

Consecutive severely traumatized patients (n = 16) requiring intensive care underwent serial monitoring of complement activation and monocyte migratory function with the chemoattractant activated serum (C5a) and formyl-methionyl-leucyl-phenylalanine (FMLP). Complement was found to be activated, and chemotaxis to C5a was correspondingly depressed maximally at a mean 5 to 7 days after injury (p = less than 0.01). The migratory response to FMLP was within the normal range throughout. Conversely, in a consecutive series of patients undergoing aortoiliac bypass grafting (n = 11), there was no evidence of complement activation, and monocyte migratory function remained normal for both C5a and FMLP. These data suggest that in patients with severe trauma, the activation of complement, particularly the fifth component (C5a), reduces the migratory responsiveness of circulating monocytes to C5a. This reduction in a host-response mechanism may explain the propensity to infection and poor wound healing seen in patients with severe trauma and also indicates that C5a, thought to be the major in vivo chemoattractant for leukocytes, has profound systemic actions.     

The role of immunoglobulin in bone marrow transplantation.

Bone marrow transplantation has proven its value as a therapeutic approach to a variety of human diseases, primarily the hematopoietic malignancies. The major clinical problems preventing successful outcome of marrow transplant have been defined and therapeutic approaches to preventing or treating these complications have led to increased long-term disease survival. Passively administered antibody given as intravenous immunoglobulin has been studied as a therapeutic modality following bone marrow transplantation. Studies have demonstrated the efficacy of immunoglobulin in reducing bacterial infections in the posttransplant period; reducing severe CMV infections in allogeneic marrow transplant recipients who are seronegative for the virus and susceptible to primary infection; reducing mortality from CMV pneumonia in combination with ganciclovir; and reducing acute graft-versus-host disease following allogeneic BMT. In many cases alternate therapeutic strategies offer comparable or greater efficacy (eg, selective CMV-negative blood products for CMV seronegative allogeneic BMT recipients receiving bone marrow from a seronegative donor). However, it is clear that intravenous immunoglobulin has a place in the therapeutic armamentarium of bone marrow transplantation. Future controlled clinical trials are necessary to establish its exact role and to define which preparations and dose schedules provide the greatest therapeutic benefits.     

The role of bone marrow and visceral fat on bone metabolism

The protective effect of total fat mass on bone mineral density (BMD) has been challenged with studies showing no or negative association after adjusting for weight. Subsequently, more studies have evaluated the relationship of regional adiposity with BMD, and findings were inconsistent for central obesity. Advancements in imaging techniques enable us to directly and noninvasively study the role of adiposity on skeletal health. Visceral adiposity measured by computed tomography (CT) has consistently been shown to have negative effects on bone. Availability of magnetic resonance spectroscopy (MRS) also allows us to noninvasively quantify bone marrow fat (BMF), which has been known to be associated with osteoporosis from histomorphometric studies. Using MRS along with dual energy x-ray absorptiometry, studies have reported a detrimental role of BMF on BMD. With the increase in aging and obesity of the population, it is important to continue this effort in identifying the contribution of adipose tissues to bone quality and fracture.     

Subtotal cystectomy with ileocystoplasty for severe hemorrhagic cystitis after bone marrow transplantation

In a retrospective analysis of hemorrhagic cystitis subsequent to allogeneic bone marrow transplantation, we focused on patients who underwent subtotal cystectomy with ileocystoplasty because stepwise use of conservative treatments had failed. Severe lasting hemorrhagic cystitis (more than 40 days) led to urinary tract obstruction and sepsis that required subtotal cystectomy in 3 of 1300 bone graft patients. Hematuria did not recur after surgery with a satisfactory functional result (follow-up 10 months to 17 years). Subtotal cystectomy with detubularized ileocystoplasty can be used to control life-threatening hemorrhagic cystitis.     

MicroRNA在强直性脊柱炎成骨、破骨机制中的作用

炎性骨破坏和新骨形成是强直性脊柱炎(ankylosing spondylitis,AS)的典型病理改变,AS早期以炎症为主,晚期出现异位骨化和骨破坏,异位骨化和骨破坏两种矛盾的表现反映了强直性脊柱炎患者成骨与破骨过程之间的动态平衡被打破。其发病机制尚不完全清楚,目前研究认为,AS复杂的新骨形成机制与Wnt/β-catenin信号通路及BMP/Smads通路密切相关,而破骨细胞则在骨破坏过程中起重要作用,RANKL/RANK/OPG系统中的细胞因子是调控破骨细胞分化成熟的关键因子。Micro RNA可调节成骨细胞、软骨细胞和破骨细胞的分化与功能,是骨形成、骨吸收、骨重塑和修复过程中的关键调节因子。研究MicroRNA在强直性脊柱炎成骨、破骨机制中的作用,可为AS的诊断和治疗提供新的依据。     

The potential role of bone marrow transplantation in augmenting donor-derived immunity to hepatitis B after rat liver transplantation

Adoptive transfer of immunity to hepatitis B virus (HBV) is not provoked solely by bone marrow, but also by liver transplantation, although transiently. In the current study, simultaneous bone marrow transplantation, which possibly can increase the number of antibody-secreting cells, was performed to augment the efficacy of transferring HBV immunity. Stimulation of donor-derived immune cells by postoperative vaccination was used to investigate whether a secondary immune response can be induced in recipients. Orthotopic liver transplantation (n = 28), performed in three rat strain combinations representing different genetic constellations, was compared with bone marrow–augmented liver transplantation (n = 21). Donors had been vaccinated twice with recombinant hepatitis B surface antigen (HBsAg). Recipients surviving more than 10 weeks received a boost vaccination. All animals were monitored weekly for the presence of antibodies to HBsAg (anti-HBs). Effective anti-HBs titers were measured in 82% of liver recipients (23 of 28 recipients) and lasted from 2 to 9 weeks. Ninety percent of bone marrow–augmented liver recipients (19 of 21 recipients) seroconverted, with anti-HBs persisting from 2 to 12 weeks. A greater seroconversion rate, prolonged titer duration, and different pattern of titer development were observed in bone marrow–augmented liver recipients, although statistical significance could not be obtained because of the small numbers of comparable animals. Posttransplantation vaccination in recipients of combined grafts did not arouse a typical secondary antibody response, but showed a tendency toward an earlier and stronger response to vaccine in comparison to recipients without immune transfer. Simultaneous bone marrow transplantation showed an augmenting, but limited, effect on humoral immune transfer. Therefore, other potentially promising cellular strategies, such as transfer of in vivo and ex vivo stimulated antigen-specific cells should be pursued further. Improvement of the effect of postoperative vaccination possibly can be achieved by optimizing the immunization protocol. (Liver Transpl 2002;8:397-404.)     

The role of calcium and cellular membrane dysfunction in experimental trauma and subarachnoid hemorrhage

Acute subarachnoid hemorrhage (SAH) and intraparenchymal hematoma (IPH) in cats are accompanied by massive cellular depolarization. This depolarization, characterized by potassium (K+) efflux and calcium (Ca++) influx, results in membrane destabilization, osmotic imbalance, and a decrease in electrical conduction. The Ca++ influx appears to initiate a chain reaction that, in some instances, may result in delayed cell destruction. The ionic dysequilibrium probably contributes to both brain engorgement and spasm in large vessels. The cellular depolarization and calcium-induced cell membrane injury at the moment of impact may play a greater role in the pathophysiology of head trauma than previously thought.     

胃肠外营养在严重多发性创伤病人中的应用

目的研究胃肠外营养支持在治疗严重多发性创伤的效果.方法从110例严重多发性创伤患者中随机选择46例进行胃肠外营养支持治疗,比较营养指标,免疫功能指标变化.结果治疗10天后,患者营养指标及免疫功能指标均明显增高.结论胃肠外营养对严重多发性创伤患者有营养支持和提高免疫功能作用,可减少并发症发生率和降低死亡率.     

The role of endoscopic retrograde pancreatography (ERP) in blunt abdominal trauma

The diagnosis of pancreatic injury is often difficult because it lies retroperitoneally in a protected area. Delayed diagnosis and treatment of blunt pancreatic trauma can result in significant morbidity and mortality. Endoscopic Retrograde Pancreatography (ERP) is infrequently used in the diagnosis of pancreatic injury. We reviewed our experience with the use of ERP in patients with blunt pancreatic injury. Two stable patients with traumatic pancreatitis underwent ERP shortly after injury. CT scans revealed a transverse fracture of the distal pancrease in one and fluid accumulation in the other around the pancreas extending to the right kidney and left hepatic lobe. The absence of ductal disruption on ERP allowed nonoperative management of the pancreatitis. Resolution was documented by the absence of symptoms on regular oral intake, normal serum amylase levels, and normal follow-up CT scans. A third patient with persistent fistulae three months postinjury underwent preoperative ERP revealing ductal obstruction. This facilitated the planning of a distal pancreatectomy and subsequently the fistulae healed. A fourth patient underwent an exploratory laparotomy on the basis of clinical and CT scan findings that could have been circumvented with preoperative ERP. ERP in selected patients allows nonoperative treatment in the absence of ductal injury or earlier operative treatment of ductal injury. It also aids the treatment of late complications by delineating ductal anatomy.