Abnormal clonogenic potential of T cells from multiple myeloma patients

Peripheral blood lymphocytes (PBLs) from multiple myeloma patients are defective in both proportion and absolute numbers of OKT4+ cells and have a normal proportion but reduced absolute number of OKT8+ cells. To assess the functional capabilities of the T cells in myeloma patients, we cloned the T cells in PBLs using limiting dilution conditions in which 100% of OKT4+ and OKT8+ T cells in normal PBLs are able to form a clone. In contrast, the OKT8+ cells from PBLs of five of seven multiple myeloma patients were severely compromised in their clonogenic potential; only 7% to 25% of OKT8+ T cells appeared to give rise to a clone. Clonogenic potential of the OKT4+ cells in patients was more nearly normal. Analysis of two multiple myeloma patients with abnormally low numbers of T cells in PBLs revealed the existence of abnormalities in the progenitors of T cell clones. In both patients, two to three times as many T cell clones were observed as would have been expected based on the number of PBLs cultured at limiting dilution, indicating that OKT4-8- cells in PBLs are capable of giving rise to OKT4+ and, at lower frequency, to OKT8+ clonal progeny in vitro. We conclude that purely quantitative assessment of T cell subsets should be interpreted with caution, since proportionately normal numbers of OKT8+ cells in patient PBLs are seriously compromised in their ability to give rise to clonal progeny in vitro, and since there appears to be a OKT4-8- population of T cells in PBLs that are committed to become OKT4+ or OKT8+ T cells, but are unable to do so in vivo.     

Randomised placebo controlled trial of aspirin and dipyridamole in the prevention of coronary vein graft occlusion

Treatment with the combination of aspirin and dipyridamole is believed to reduce the incidence of coronary vein graft occlusion. A double blind randomised controlled trial was carried out in which aspirin 990 mg and dipyridamole 225 mg daily or placebo were added to the routine postoperative management (warfarin for three months) of 320 patients undergoing coronary bypass grafting. The trial treatment was given for 12 months, after which the results were assessed by coronary and graft angiography. The two randomised groups, each of 160 patients, were comparable in age, sex, symptomatic state, angiographic findings, and operative procedure. Repeat coronary arteriography was carried out on 266 patients, 133 in each group. All grafts and distal anastomoses were patent in 68% (91/133) of the placebo patients and in 75% (100/133) of those receiving active treatment. Overall graft patency was 87% (306/352) and 89% (342/385) respectively. Retrospective subgroup analysis showed patency rates of 72% (26/36) and 78% (39/50) of grafts to vessels requiring preliminary endarterectomy, and 80% (36/45) and 91% (40/44) of distal anastomoses to vessels measured at operation to have a diameter of less than or equal to 1 mm. None of these differences was significant at the 5% level. Thus in this group of patients with high graft patency rates, treatment with aspirin and dipyridamole conferred no appreciable advantage.     

MR accuracy and arthroscopic incidence of meniscal radial tears

OBJECTIVE: A meniscal radial tear is a vertical tear that involves the inner meniscal margin. The tear is most frequent in the middle third of the lateral meniscus and may extend outward in any direction. We report (1) the arthroscopic incidence of radial tears, (2) MR signs that aid in the detection of radial tears and (3) our prospective accuracy in detection of radial tears. DESIGN AND PATIENTS: Three musculoskeletal radiologists prospectively read 200 consecutive MR examinations of the knee that went on to arthroscopy by one orthopedic surgeon. MR images were assessed for location and MR characteristics of radial tears. MR criteria used for diagnosis of a radial tear were those outlined by Tuckman et al.: truncation, abnormal morphology and/or lack of continuity or absence of the meniscus on one or more MR images. An additional criterion used was abnormal increased signal in that area on fat-saturated proton density or T2-weighted coronal and sagittal images. Prospective MR readings were correlated with the arthroscopic findings. RESULTS: Of the 200 consecutive knee arthroscopies, 28 patients had radial tears reported arthroscopically (14% incidence). MR readings prospectively demonstrated 19 of the 28 radial tears (68% sensitivity) when the criteria for diagnosis of a radial tear were truncation or abnormal morphology of the meniscus. With the use of the additional criterion of increased signal in the area of abnormal morphology on fat-saturated T2-weighted or proton density weighted sequences, the prospective sensitivity was 25 of 28 radial tears (89% sensitivity). There were no radial tears described in MR reports that were not demonstrated on arthroscopy (i.e., there were no false positive MR readings of radial tears in these 200 patients). CONCLUSIONS: Radial tears are commonly seen at arthroscopy. There was a 14% incidence in this series of 200 patients who underwent arthroscopy. Prospective detection of radial tears was 68% as compared with arthroscopy when the criteria as outlined by Tuckman et al. were used alone. With the use of the additional criterion of increased signal in the area of abnormal morphology on fat-saturated T2-weighted and proton density weighted sequences, the prospective sensitivity for radial tear detection as compared with arthroscopy was 89% in our series. Fat-saturated proton density and T2-weighted images greatly improve the detection of radial tears as signal intensity changes in radial tears as well as morphologic changes can be utilized for the detection of subtle tears.     

Emergency thoracotomy in the pre-hospital setting: a procedure requiring clarification.

OBJECTIVE: The aim of this study is to investigate the influence of Emergency Thoracotomy (ET) on mortality in a group of patients suffering from severe thoracic trauma requiring Helicopter Emergency Medical Service (HEMS) transfer to hospital. This is not clearly defined especially when thoracotomy takes place in the pre-hospital setting. METHODS: A retrospective review of 670 consecutive patients with severe thoracic trauma, transferred to The Royal London Hospital by HEMS between November 1994 and December 2002. ET (on scene, in the Accident and Emergency (A&E) department or in the operating theatre) was performed in 53 patients (7.7%). Both univariate and multivariate analyses were performed to evaluate ET as an independent predictor of mortality. RESULTS: There were 510 males and 160 females with a mean Injury Severity Score (ISS) of 35.12+/-17.5. Univariate analysis identified ET to be a predictor of mortality (OR=0.15, 95% CI=0.07-0.30). However, with multivariate analysis, ET was not found to be an independent predictor of mortality (OR=1.93, 95% CI=0.61-6.1). The independent predictors of mortality identified were: age>60 years (OR 5.57, 95% CI 2.19-14.16), Glasgow Coma Score <8 at the scene (OR=7.4, 95% CI=3.15-17.46), ISS>25 (OR 5.3, 95% CI=1.64-17.11), need for intubation at the scene (OR=2.80, 95% CI=1.022-7.69), oxygen saturation in A&E (<89%) (OR=2.39, 95% CI=1.13-5.05), haemothorax (OR=3.30, 95% CI=1.53-7.13) and bilateral injury (OR=3.1, 95% CI=1.51-6.61). CONCLUSIONS: Our study has shown that when confounding variables are accounted for, ET is not a predictor of mortality following severe chest trauma. This implies that in a well-selected group of patients it may be a significant and life-saving procedure.