The association between killer‐cell immunoglobulin‐like receptor (KIR) and KIR ligand genotypes and the likelihood of BK virus replication after kidney transplantation

BK virus is a common opportunistic post‐transplantation viral infection. Although some risk factors have been studied in this context, the contribution of NK cells has not been assessed in detail. In a group of kidney transplant recipients, we studied the association between (i) the likelihood of BK virus replication during the two‐year period after kidney transplantation and (ii) the genotypes of the killer cell immunoglobulin‐like receptor (KIR) repertoire and their human leukocyte antigen (HLA) ligands. Other clinical factors (such as defective organ recovery and immunosuppressive treatment) were also assessed. BK virus replication was observed in 43 of the 103 recipients (41%). Patients with BK virus replication in the plasma were more likely to display defective organ recovery in the first seven days post‐transplantation. BK virus replication was not associated with Missing KIR ligands. However, BK virus replication was more frequent in patients with responsive NK cells (i.e. when a ligand for activating KIRs was not homozygous in the recipient and present in the donor). Our results suggest that defective organ recovery and the recipient's activating KIR repertoire may be related (depending on HLA ligands present in the couple recipient / donor) to the reactivation of BK virus replication after kidney transplantation.     

Thoracoscopic diaphragmatic eventration repair in children: about 10 cases

Background and Aim

Recent reports in literature have emphasized the clinical perception of reduced pain, postoperative morbidity, and dysfunction associated with thoracoscopic approach compared with standard thoracotomy.The authors describe a thoracoscopic approach and technical details for diaphragmatic eventration repair in children.

Patients and Methods

Ten patients, 4 girls and 6 boys, 1 teenager (14 years old) and 9 children (age range, 6-41 months; average, 17 months), were operated for a diaphragmatic eventration in 3 different pediatric surgery teams, according to the same technique. Symptoms were recurrent infection (7 cases), dyspnea on exertion (2 cases), and a rib deformity (1 case). An elective thoracoscopy was performed, patient in a lateral decubitus. A low carbon dioxide insufflation allowed a lung collapse. Reduction of the eventration was made progressively when folding and plicating the diaphragm. Plication of the diaphragm was done with an interrupted suture (6 cases) or a running suture (4 cases). The procedure finished either with an exsufflation (4 cases) or a drain (6 cases).

Results

A conversion was necessary in 2 cases: 1 insufflation was not tolerated and 1 diaphragm, higher than the fifth space, reduced too much the operative field. Patients recovered between 2 and 4 days. Dyspnea disappeared immediately. Mean follow-up of 16 months could assess the clinical improvement in every patient.

Discussion

Thoracoscopic conditions are quite different between a diaphragmatic hernia repair previously reported and an eventration. Concerning diaphragmatic hernias, reduction is easy, giving a large operative space for suturing the diaphragm. Concerning diaphragmatic eventrations, the lack of space remains important at the beginning of the procedure despite the insufflation into the pleural cavity. The operative ports must be high enough in the chest to allow a good mobility of the instruments. Chest drainage seems to be unnecessary.

Conclusion

Diaphragmatic eventration repair by thoracoscopy is feasible, safe, and efficient in children. Above all, it avoids a thoracotomy. It improves the immediate postoperative results with a good respiratory function.     

Prevalence of lymph nodes in the apex of level V: a plea against the necessity to dissect the apex of level V in mucosal head and neck cancer

BACKGROUND: We assessed the prevalence of histologically proven normal or invaded lymph nodes in the apex of level V. METHODS: Seventy neck dissections were performed in 41 patients with mucosal head and neck squamous cell carcinoma (SCC). Fifty-one neck dissections were performed in 30 previously untreated patients (group 1); 19 neck dissections were carried out in 11 patients previously irradiated (group 2). RESULTS: Pathologic analysis was unable to identify any lymph node in 70% of the apex specimens. In group 1, no lymph nodes were detected in 63%, whereas one or more noninvaded lymph nodes were present in 37%; in group 2, no lymph nodes were identified in 89%, whereas one or more normal lymph nodes were found in 11% (p = .03). Metastatic lymph nodes were never identified. CONCLUSIONS: The prevalence of lymph nodes in the apex was 30%. No invaded lymph nodes were identified. In addition to anatomic evidence, these results suggest that dissection of the apex is not necessary in mucosal head and neck SCC.     

Regulatory role of host CD8+ T lymphocytes in experimental graft-versus-host disease across a single major histocompatibility complex class II incompatibility

BACKGROUND: CD8+ T cells are known to regulate type 2 helper T cell (Th2) alloreactive immune responses but their mode of activation is unclear. We investigated the role of host CD8+ T cells in experimental Th2-type graft-versus-host disease (GVHD) where donor/recipient disparity is restricted to a single major histocompatibility complex (MHC) class II antigen. METHODS: Immunoglobulin (Ig) E serum levels, eosinophilia and lymphoid tissue hyperplasia were compared after injection of bm12 CD4+ T cells in either wild-type or CD8+ T cell-deficient (CD8-/-) C57BL/6 mice. In vitro, we explored effects of the addition of CD8+ T cells from wild-type or IFN-gamma-/- mice in mixed leukocyte cultures prepared with beta2 microglobulin-deficient (beta2m-/-) CD4+ T cells as responders or beta2m dendritic cells as stimulators. RESULTS: HyperIgE resolved after 3 weeks in wild-type hosts whereas it persisted for 6 weeks in CD8-/- hosts. Eosinophil infiltrates in lymph nodes were significantly enhanced in CD8-/- hosts. Increased serum levels of IL-5 and IL-13 in CD8-/- hosts confirmed the enhancement of Th2-type responses in the context of recipient CD8+ T cell deficiency. Hyperplasia of lymph nodes and spleen were similar in both groups, as well as in vivo proliferation of donor CD4+ T cells. In vitro, CD8+ T cell regulation of the alloreactive Th2 response depended on their production of IFN-gamma and did not require expression of beta2m on CD4+ T cells or antigen-presenting cells. CONCLUSIONS: Host CD8+ T cells regulate alloreactive Th2 responses during graft-versus-host disease through an IFN-gamma dependent pathway, independently of the recognition of beta2m-associated MHC class I molecules.     

Which parameters are needed for targeting a multitined radiofrequency device—an approach to a simple algorithm

Background  The use of radiofrequency ablation (RFA) for treatment of liver malignancies is limited by the high rate of local recurrences. The aim of this experimental study was to evaluate parameters describing the reproducible target volume of a RFA procedure in order to facilitate better applicator placement. Materials and methods  RFA was performed in perfused and nonperfused pig livers. The following parameters were measured: axial and transverse diameter, front margin, coagulation center, diameter of sphere ablated (D _S), distance to center (DC), and volume. Graphic overlays were utilized to visualize variability. Parameters were evaluated for Rita XL (2 algorithms), LeVeen, and Rita Xli applicators. Results  The best prediction of a reproducibly ablated target volume can be made by the diameter of the sphere ablated and the distance of the applicator tip to center of the sphere (DC). The spheres were significantly different in diameter (D _S) depending on the applicator Rita XL 29 ± 6 mm, Rita XL^wet 35 ± 5 mm, LeVeen 35 ± 8 mm, Rita Xli 44 ± 5 mm (perfused livers, p < 0.001). Graphic overlay demonstrated differences in variability that can influence the reliability of the system. Conclusions   D _S and DC as specific values for each applicator and algorithm facilitate a placement of the applicator relative to the target volume that maximizes the chance of complete ablation.     

Detection of residual packets in cocaine body packers: low accuracy of abdominal radiography—a prospective study

Objective

To evaluate the accuracy of abdominal radiography (AXR) for the detection of residual cocaine packets by comparison with computed tomography (CT).

Methods

Over a 1-year period unenhanced CT was systematically performed in addition to AXR for pre-discharge evaluation of cocaine body packers. AXR and CT were interpreted independently by two radiologists blinded to clinical outcome. Patient and packet characteristics were compared between the groups with residual portage and complete decontamination.

Results

Among 138 body packers studied, 14 (10 %) had one residual packet identified on pre-discharge CT. On AXR, at least one reader failed to detect the residual packet in 10 (70 %) of these 14 body packers. The sensitivity and specificity of AXR were 28.6 % (95 % CI: 8.4–58.1) and 100.0 % (95 % CI: 97.0–100.0) for reader 1 and 35.7 % (95 % CI: 12.8–64.9) and 97.6 % (95 % CI: 93.1–99.5) for reader 2. There were no significant patient or packet characteristics predictive of residual portage or AXR false negativity. All positive CT results were confirmed by delayed expulsion or surgical findings, while negative results were confirmed by further surveillance.

Conclusion

Given the poor performance of AXR, CT should be systematically performed to ensure safe hospital discharge of cocaine body packers.

Key Points

? Both abdominal radiography and computed tomography can identify gastrointestinal cocaine packets. ? Ten per cent of body packers had residual packets despite two packet-free stools. ? Seventy per cent of these residual packets were missed on AXR. ? No patient or packet characteristics predicted residual packets or AXR false negativity. ? CT is necessary to ensure safe medical discharge of body packers.     

Language functional magnetic resonance imaging in preoperative assessment of language areas: correlation with direct cortical stimulation

OBJECTIVE: The aim of this study was to analyze the usefulness of preoperative language functional magnetic resonance imaging (fMRI), by correlating fMRI data with intraoperative cortical stimulation results for patients with brain tumors. METHODS: Naming and verb generation tasks were used, separately or in combination, for 14 right-handed patients with tumors in the left hemisphere. fMRI data obtained were analyzed with SPM software, with two standard analysis thresholds (P < 0.005 and then P < 0.05). The fMRI data were then registered in a frameless stereotactic neuronavigational device and correlated with direct brain mapping results. We used a statistical model with the fMRI information as a predictor, spatially correlating each intraoperatively mapped cortical site with fMRI data integrated in the neuronavigational system (site-by-site correlation). Eight patients were also studied with language fMRI postoperatively, with the same acquisition protocol. RESULTS: We observed high variability in signal extents and locations among patients with both tasks. The activated areas were located mainly in the left hemisphere in the middle and inferior frontal gyri (F2 and F3), the superior and middle temporal gyri (T1 and T2), and the supramarginal and angular gyri. A total of 426 cortical sites were tested for each task among the 14 patients. In frontal and temporoparietal areas, poor sensitivity of the fMRI technique was observed for the naming and verb generation tasks (22 and 36%, respectively) with P < 0.005 as the analysis threshold. Although not perfect, the specificity of the fMRI technique was good in all conditions (97% for the naming task and 98% for the verb generation task). Better correlation (sensitivity, 59%; specificity, 97%) was achieved by combining the two fMRI tasks. Variation of the analysis threshold to P < 0.05 increased the sensitivity to 66% while decreasing the specificity to 91%. Postoperative fMRI data (for the cortical brain areas studied intraoperatively) were in accordance with brain mapping results for six of eight patients. Complete agreement between pre- and postoperative fMRI studies and direct brain mapping results was observed for only three of eight patients. CONCLUSION: With the paradigms and analysis thresholds used in this study, language fMRI data obtained with naming or verb generation tasks, before and after surgery, were imperfectly correlated with intraoperative brain mapping results. A better correlation could be obtained by combining the fMRI tasks. The overall results of this study demonstrated that language fMRI could not be used to make critical surgical decisions in the absence of direct brain mapping. Other acquisition protocols are required for evaluation of the potential role of language fMRI in the accurate detection of essential cortical language areas.