Impact of bodyweight-adjusted antimicrobial prophylaxis on surgical-site infection rates.

BACKGROUND: Antimicrobial prophylaxis (AMP) adjustment according to bodyweight to prevent surgical-site infections (SSI) is controversial. The impact of weight-adjusted AMP dosing on SSI rates was investigated here. METHODS: Results from a first study of patients undergoing visceral, vascular or trauma operations, and receiving standard AMP, enabled retrospective evaluation of the impact of bodyweight and BMI on SSI rates, and identification of patients eligible for weight-adjusted AMP. In a subsequent observational prospective study, patients weighing at least 80 kg were assigned to receive double-dose AMP. Risk factors for SSI, including ASA classification, duration and type of surgery, wound class, diabetes, weight in kilograms, BMI, age, and AMP dose, were evaluated in multivariable analysis. RESULTS: In the first study (3508 patients), bodyweight and BMI significantly correlated with higher rates of all SSI subclasses (both P < 0.001). An 80-kg cut-off identified patients receiving single-dose AMP who were at higher risk of SSI. In the prospective study (2161 patients), 546 patients weighing 80 kg or more who received only single-dose AMP had higher rates of all SSI types than a group of 1615 who received double-dose AMP (odds ratio (OR) 4.40, 95 per cent c.i. 3.18 to 6.23; P < 0.001). In multivariable analysis including 5021 patients from both cohorts, bodyweight (OR 1.01, 1.00 to 1.02; P = 0.008), BMI (OR 1.01, 1.00 to 1.02; P = 0.007) and double-dose AMP (OR 0.33, 0.23 to 0.46; P < 0.001) among other variables were independently associated with SSI rates. CONCLUSION: Double-dose AMP decreases SSI rates in patients weighing 80 kg or more.

Surveillance of surgical site infections by surgeons: biased underreporting or useful epidemiological data?

Surgical site infections (SSIs) significantly increase post-operative morbidity and mortality. SSI surveillance is an established monitoring tool and reduces SSI rates. The purpose of this study was to compare prospective in-hospital SSI surveillance (I) by the surgical staff and (II) additionally by an infection control team (ICT). The reference method (III) was defined by data generated by the surgical team, supplemented by the ICT and completed by post-discharge surveillance with a post-operative follow-up of one year representing the sum of all available resources. During 24 months, all consecutive inpatient procedures (N=6283) were prospectively recorded by the surgical staff until patients' discharge (I). SSI rates were compared with the surveillance performed by the ICT (II) and with the reference method (III). The overall SSI rate (reference method) was 4.7% (N=293), of which 187 (63.8%) were detected in-hospital and 106 (36.2%) after discharge. (I) The surgical staff detected 91/187 (48.7%) of in-hospital SSIs [91/293 (31.0%) of the reference], (II) the ICT an additional 96/187 (51.3%) during hospitalisation [96/293 (32.8%) of the reference]. Further cross-checking as performed in the visceral surgery department increased the surgeons' detection rate (I) to 59/105 (56.2%) of in-hospital SSIs [59/147 (40.1%) of the reference]. SSI surveillance by the surgical staff detects almost half of all in-hospital SSIs and has the potential to increase the detection rate by simple interventions such as cross-checking. Such a relatively inexpensive surveillance system is an option for hospitals without an ICT or for low risk surgical procedures. Moreover, trends in SSI rates can easily be detected, allowing early intervention.

[The patient with a stoma]. / Der Patient als Stomaträger.

After formation of a stoma patients quality of life can be compromised. This includes body image, capacity to work, leisure time and sexual activity. After leaving the hospital it is essential, that stoma patients are supported by professionals on the long run. This can be achieved by a network of stoma-care nurses, social workers and psychology professionals.

Encapsulation into sterically stabilised liposomes enhances the immunogenicity of melanoma-associated Melan-A/MART-1 epitopes.

Tumour-associated antigens (TAA)-specific vaccination requires highly immunogenic reagents capable of inducing cytotoxic T cells (CTL). Soluble peptides are currently used in clinical applications despite an acknowledged poor immunogenicity. Encapsulation into liposomes has been suggested to improve the immunogenicity of discrete antigen formulations. We comparatively evaluated the capacity of HLA-A2.1 restricted Melan-A/MART-1 epitopes in soluble form (S) or following inclusion into sterically stabilised liposomes (SSL) to be recognised by specific CTL, to stimulate their proliferation and to induce them in healthy donors' peripheral blood mononuclear cells (PBMC), as well as in melanoma-derived tumour-infiltrating lymphocytes (TIL). HLA-A2.1(+), Melan-A/MART-1-NA-8 melanoma cells served as targets of specific CTL in 51Cr release assays upon pulsing by untreated or human plasma-treated soluble or SSL-encapsulated Melan-A/MART-1 27-35 (M27-35) or 26-35 (M26-35) epitopes. These reagents were also used to stimulate CTL proliferation, measured as 3H-thymidine incorporation, in the presence of immature dendritic cells (iDC), as antigen-presenting cells (APC). Induction of specific CTL upon stimulation with soluble or SSL-encapsulated peptides was attempted in healthy donors' PBMC or melanoma-derived TIL, and monitored by 51Cr release assays and tetramer staining. Na-8 cells pulsing with SSL M27-35 resulted in a five-fold more effective killing by specific CTL as compared with equal amounts of S M27-35. Encapsulation into SSL also provided a partial (50%) protection of M27-35 from plasma hydrolysis. No specific advantages regarding M26-35 were detectable in these assays. However, at low epitope concentrations (

Perioperative detection of disseminated tumour cells is an independent prognostic factor in patients with colorectal cancer.

BACKGROUND: The objective of the present investigation was to assess the prognostic significance of disseminated tumour cells in peritoneal lavage, and peripheral and mesenteric venous blood in patients undergoing curative resection of colorectal cancer. METHODS: The prognostic impact of perioperative cytological and immunocytochemical detection of disseminated colorectal cancer cells was evaluated prospectively. Peritoneal lavage fluid, and peripheral and mesenteric venous blood from 53 consecutive patients undergoing curative surgery for colorectal cancer were analysed. The dichotomous results (positive versus negative) from the cytological and immunocytochemical analysis were used as a predictor along with other co-variates in proportional hazard regression models of disease-free and overall survival. RESULTS: Disseminated colorectal cancer cells were found in 13 of 53 patients (25 per cent) using cytology (CYT) and/or immunocytochemistry (ICC). The median follow-up at the time of the analysis was 37 months. In multivariate proportional hazard regression models CYT/ICC status was a significant predictor for disease-free (P = 0.002) and overall (P = 0.006) survival. CONCLUSION: Disseminated tumour cells detected by CYT and ICC represent an independent prognostic factor in patients undergoing surgery for colorectal cancer and may identify patients at high risk of recurrence.

Peritoneal mesothelioma after environmental asbestos exposure.

Mesothelioma are primary malignant neoplasms of the serous membranes. They usually involve the pleura and rarely the pericardium, the peritoneum and the tunica vaginalis testis. About 90% are associated with exposure to asbestos. The exposure is generally occupational, an environmental inhalation of asbestos and asbestiform fibers in areas in Turkey has been observed and presents a major health problem. This report of a patient from Anatolia with peritoneal mesothelioma after environmental exposure outlines the importance of considering this pathology in the differential diagnosis of a Turkish patient presenting with ascites.

[Malignant transformation of perianal Buschke-Löwenstein tumor. Extensive abdominoperineal rectum excision and reconstruction with transpelvic myocutaneous rectus abdominis muscle flap]. / Maligne entarteter perianaler Buschke-Löwenstein-Tumor. Ausgedehnte abdominoperineale Rektumamputation und Rekonstruktion mit transpelvinem myokutanem M.-rectus-abdominis-Lappen.

INTRODUCTION: The Buschke Löwenstein tumor (giant condyloma) in its perianal variant is an extremely rare disease caused by human papilloma virus. Although of histologically benign appearance, it infiltrates and destroys the surrounding tissue. There is a high risk of local recurrence and malignant transformation. The treatment of choice is wide surgical resection. CASE: A 56-year-old woman presented with perianal giant condyloma infiltrating the rectum and vagina. The extensive soft tissue defect resulting from wide resection was filled with a transpelvic myocutaneous rectus abdominis flap. Histology showed a squamous cell carcinoma arising in the Buschke Löwenstein tumor with clear resection margins. Therefore, the patient was irradiated locally after uneventful primary wound healing. CONCLUSION: A simultaneous reconstruction of a large pelvinoperineal soft tissue defect with the transpelvic myocutaneous rectus abdominis flap allows primary healing, accelerated rehabilitation, and safe adjuvant radiotherapy without risk of serious radiation damage to the small bowel by preventing it from protruding into the pelvic defect.

Immunogenicity of nonreplicating recombinant vaccinia expressing HLA-A201 targeted or complete MART-1/Melan-A antigen.

The effect on immunogenicity of different tumor T cell epitope formulations was evaluated in vitro using nonreplicating recombinant vaccinia vector expressing two forms of the melanoma-associated MART-1/Melan-A antigen. The first recombinant virus expressed a minigene encoding a fusion product between an endoplasmic reticulum (ER)-targeting signal and the HLA-A201 binding 27-35 peptide. The second viral construct encoded the complete MART-1/Melan-A protein. The capacity of HLA-A201 cells infected with either viral construct to generate and to stimulate MART-1/Melan-A 27-35 specific cytotoxic T-lymphocytes (CTL), was comparatively characterized. The results obtained here with a tumor antigen confirmed the capacity of vaccinia virus-encoded ER-minigene to generate a very strong antigenic signal. In cytotoxicity assays, recognition of target cells infected with high amounts of both recombinant viruses with activated specific CTL clones, resulted in similar lytic activity. With regard to calcium mobilization, TCR down-regulation, IFN-gamma release, and T cell proliferation assays, the targeted epitope elicited 10- to 1000-fold stronger responses. Remarkably, the immunogenic difference between the two formulations, in their respective capacity to generate CTL from naive HLA-A2 peripheral blood mononuclear cells in vitro as measured by tetramer detection, was lower (2- to 3-fold). Recombinant vectors expressing complete antigens have demonstrated their capacity to generate specific responses and such vaccines might take advantage of a broader potential of presentation. However, as demonstrated here for the HLA-A201-restricted MART-1/Melan-A immunodominant epitope, nonreplicative vaccinia virus expressing ER-targeted minigenes appear to represent a significantly more immunogenic epitope vaccine formulation.

Advanced breast biopsy instrumentation for the evaluation of impalpable lesions: a reliable diagnostic tool with little therapeutic potential.

OBJECTIVE: To assess the potential of advanced breast biopsy instrumentation (ABBI) to clarify the diagnosis of impalpable mammographic lesions and to remove the entire malignant lesions with clear margins. DESIGN: Prospective assessment in a consecutive series of patients. SETTING: University hospital, Basel, Switzerland. SUBJECTS: 139 patients presenting with 144 impalpable microcalcifications or solid nodular densities evident on screening and follow-up mammograms that were suspicious of malignancy. MAIN OUTCOME MEASURES: Feasibility, sensitivity, efficiency in obtaining definitive diagnoses in an outpatient clinic under local anaesthesia, feasibility of complete removal of a primary malignancy, and intervention-related morbidity. RESULTS: The ABBI procedure was successful in 135/144 (94%); an accurate diagnosis was made in 129/130 patients followed up (99%), sensitivity for malignant lesions was 31/32 (97%) and there were 2 complications (2%). Margins of the biopsy cylinder contained a malignant lesion in 26/31 (84%). CONCLUSIONS: Excisional biopsy using the ABBI system is a reliable diagnostic tool with a low morbidity. As in other published series margins were often not clear of tumour and therefore the therapeutic use of the ABBI procedure is limited.

[The Advanced Breast Biopsy Instrumentation (ABBI) for evaluation of mammographically suspicious, non-palpable findings of the breast: a reliable diagnosis with minor therapeutic potential]. / Die Advanced Breast Biopsy Instrumentation (ABBI) für die Evaluation mammographisch verdächtiger, nicht-palpabler Befunde der Brustdrüse: Eine zuverlässige Diagnostik mit geringem therapeutischen Potential.

BACKGROUND: Stereotactic biopsy techniques supersede conventional hook-wire localization followed by open excision to clarify the dignity of nonpalpable mammographic lesions. The advanced breast biopsy instrumentation (ABBI) allows stereotactically guided excision of a specimen up to 20 mm in diameter on an outpatient basis under local anaesthesia. METHODS: Demographic information, mammographic and pathological findings, complications, subsequent interventions and sensitivity as well as efficiency of a series of 144 planned ABBI procedures were documented (largest published single institution series). RESULTS: The ABBI procedure was successfully performed in 93.8% (135/144); accurate diagnosis was made in 99.3% (134/135), sensitivity for malignant lesions was 96.9% (31/32) and morbidity was 1.5%. Consistent with other published series margins of the biopsy cylinder containing a malignant lesion were involved in 83.9% (26/31). CONCLUSIONS: Excisional biopsy using the ABBI system is a reliable diagnostic tool with a low incidence of morbidity. The therapeutic use is of limited potential.

Enhanced generation of cytotoxic T lymphocytes using recombinant vaccinia virus expressing human tumor-associated antigens and B7 costimulatory molecules.

In this work, we addressed the possibility to enhance the "in vitro" generation of CTLs recognizing tumor-associated antigens (TAAs) by using an inactivated recombinant vaccinia virus encoding B7.1 and B7.2 costimulatory molecules (rVV-B7.1/2). Antigen presenting cells (APCs) infected by rVV-B7.1/2 and pulsed with MART-1/Melan-A27-35 HLA-A2.1-restricted peptide induced significantly higher specific cytotoxic activity than peptide-loaded APCs infected by wild-type VV, both in VV-sensitized and naive donors. When APCs were infected with a rVV encoding both MART-1/Melan-A27-35 and B7-1/2 (rVV-B7.1/2-M), a significantly more effective CTL generation was observed as compared with cultures stimulated by APCs infected with a rVV encoding the TAA epitope only (rVV-M). These enhancing effects were detectable irrespective of a previous VV-specific sensitization. Most importantly, fibroblasts, devoid of antigen-presenting capacity upon peptide pulsing or infection with rVV-M, could be turned into effective APCs after infection by rVV encoding TAA epitopes and costimulatory molecules. In these experiments, by using separate recombinant viral constructs, we observed a predominant role of B7-1 as compared with B7-2 in the induction of TAA-specific CTLs. Taken together, our data indicate that replication-incompetent rVV encoding TAA epitopes and costimulatory molecules are able to induce highly effective generation of tumor-specific CTLs. Therefore, these vectors could represent valuable clinical tools for immunotherapy of melanoma patients.

[Superficial femoral vein as vascular graft in surgical therapy of mycotic aneurysm of the common iliac artery]. / Die Vena femoralis superficialis als Gefässersatz bei der chirurgischen Therapie eines mykotischen Aneurysmas der Arteria iliaca communis.

A 38-year-old polytoxicomanic male patient developed an occlusion of both popliteal arteries associated with an aneurysm of the right common iliac artery. A septic cause was suspected and an antimycotic therapy was instituted, but the diameter of the aneurysm increased to 3 cm during 6 months. Moreover, multiple periarterial abscesses occurred. The aneurysm was resected and the iliacal axis reconstructed in situ, using a superficial femoral vein interposition. Six months after operation, patency was confirmed by duplex sonography. Phlebodynamic examinations showed normal flow functions at the donor site.

[The Advanced Breast Biopsy Instrumentation (ABBI), a system for stereotactic excision of mammographically suspect nonpalpable findings in the breast]. / Die Advanced Breast Biopsy Instrumentation (ABBI), ein System zur stereotaktischen Exzision mammographisch verdächtiger nicht-palpabler Befunde der Brustdrüse.

Advanced Breast Biopsy Instrumentation (ABBI) allows radiologically guided stereotactic excision of non-palpable radiodense lesions with high accuracy. Tissue cylinders of 5, 10, 15 or 20 mm diameter and of variable lengths can be removed very accurately under local anaesthesia and on an outpatient basis. Thirty-six patients with suspicious clusters of microcalcifications (n = 29) and with round lesions (n = 7) of the breast were qualified for ABBI. We were able to perform the excisional biopsy in a total of 34 patients. The breast of one woman was too small to safely fit into the system and in another woman the lesion could not be visualized by the system. In 2/34 cases (6%), the excision was imprecise due to slight dislocation of the breast parenchyma by the advancing cylinder knife. In one case (3%), ABBI missed the target within a dense mastopathic breast. In all cases the excisions were well tolerated. No wound complications occurred and the cosmetic result was excellent. Histology revealed 28 benign (82%) and 6 malignant (18%) lesions. Among the 27 small microcalcifications there were 3 invasive carcinomas, 3 ductal carcinomas in situ (DCIS), 1 lobular hyperplasia, 14 mastopathies, 1 fibroadenoma, 1 duct papilloma and 4 calcifications in scars. Four of the 7 round-shaped lesions were found to be fibroadenomas, 1 lobular hyperplasia, and 2 mastopathies. With the ABBI system, non-palpable breast lesions can be precisely localized and excised.

[Initial experiences with the Advanced Breast Biopsy Instrumentation (ABBI), a system for stereotactic excision of non-palpable breast lesions]. / Erste Erfahrungen mit der Advanced Breast Biopsy Instrumentation (ABBI), einem System zur stereotaktischen Exzision nicht-palpabler Mammabefunde.

The advanced breast biopsy instrumentation (ABBI) allows the radiologically guided stereotactic excision of non-palpable radiodense lesions with high accuracy. Forty-six patients with suspicious clusters of microcalcifications (n = 37) and with round lesions (n = 9) of the breast were investigated using the ABBI. Tissue cylinders were successfully removed in 98% of cases. No wound complications occurred and cosmesis was excellent. Histopathology revealed 35 benign (76%) and 11 malignant (24%) lesions. With the ABBI system, non-palpable breast lesions can be precisely localized and excised.

[B7 costimulation molecules improve induction of tumor specific cytotoxic T-cells against MART-1(27-35)]. / B7-Kostimulationsmoleküle verbessern die Induktion tumorspezifischer zytotoxischer T-Zellen gegen MART-1(27-35).

The expression of B7-1/2 molecules in addition to TAA in APC significantly improves the generation of specific CTL in vitro. Moreover, human fibroblasts, usually devoid of APC capacity, can be engineered into effective APC upon infection with recVV encoding costimulatory molecules together with specific epitopes. The generation of artificial APC by infection of non professional APC with appropriately engineered recVV is a new concept that may be useful in the implementation of immunotherapy strategies.

[Recombinant vaccinia viruses as efficient vectors of biologically active, human B7 costimulation molecules]. / Rekombinante Vakzinia Viren als effiziente Vektoren biologisch aktiver, humaner B7-Kostimulationsmoleküle.

A specific antigenic ligand and a costimulatory signal are required for optimal T cell activation. We constructed and tested recombinant Vaccinia viruses (recVV) expressing hB7-1 or hB7-2 as a gene expression vector system for delivery of costimulatory function in vitro. Upon infection with replication incompetent and non-cytopathic recVV B7, all human tumour cell lines tested expressed the recombinant molecules. Cell lines expressing recombinant B7 molecules provided effective costimulation for proliferation of resting CD4+ T helper cells in the presence of suboptimal PMA concentrations. The costimulatory effect could be blocked with soluble CTLA-4 proteins. RecVV B7-1 infected EBV transformed B-lymphocytes overexpressed the costimulatory molecules resulting in enhanced costimulation. The capacity of these cells to stimulate autologous CD4+ memory cells of VV immunocompetent donors was not impared by the recVV infection indicating an intact capacity for processing and presenting antigenic proteins in the context with MHC Class II molecules remained. RecVV encoding human B7 molecules therefore appear to be promising experimental and clinical tools to enhance immune responses.

Artificial antigen-presenting cells engineered by recombinant vaccinia viruses expressing antigen, MHC class II, and costimulatory molecules elicit proliferation of CD4+ lymphocytes in vitro.

The current study was designed to test the ability of recombinant Vaccinia virus (rVV) encoding essential components of an artificial antigen-presenting cell to activate antigen-specific T cells in vitro. We have constructed a set of rVV encoding separately or in combination a CD4+ T cell-specific epitope (the 133-145 peptide of chicken conalbumin), the MHC class II molecule I-Ak, and costimulatory molecules (mB7-1 and mB7-2). Cultured cells infected with rVV encoding both the antigen and the presenting MHC, but not either one alone, could activate cloned CD4+ T cells specific for the virus-encoded epitope. Additional co-expression of mB7-1 and mB7-2 resulted in further enhancement of T cell response. Thus, our rVV vector expressing four different foreign gene products elicited the highest proliferation rates of antigen-specific cloned T cells.