Alloimmunization and autoimmunization in adult transfusion-dependent thalassemia patients: a report from a comprehensive center in Israel

Patients with beta thalassemia major (TM) are transfusion-dependent (TD) since early childhood and for life. Development of alloantibodies and autoantibodies against red blood cell (RBC) antigens is increasingly recognized as a significant transfusion hazard, especially among heavily transfused patients. The aim of this study is to assess RBC alloimmunization and autoimmunization rates in TD TM patients treated in our Comprehensive Center of Adult Thalassemia, Hemoglobinopathies and Rare Anemias. TD TM patients, regularly transfused every 2-3 weeks, were included in the study. Clinical and RBC transfusion records, including RBC antibodies, since diagnosis in early childhood, were retrieved from patients' files and from the blood bank database. Forty TD TM patients, > 18 years of age, were included in the study. Alloimmunization was demonstrated in 17 (42.5%) patients. Thirty-four alloantibodies were detected, with the most frequent being RH related (12 of 34, 35.3%) followed by those of the Kell system (8 of 34, 23.5%). Age at first transfusion was positively related to the probability of developing alloantibodies (p = 0.02). Splenectomy was found to be correlated with developing alloantibodies (p = 0.016). Logistic regression analysis of the lifelong probability of developing alloantibodies on the age at first transfusion and splenectomy demonstrates a strong positive relationship (p = 0.002). A substantially high rate of alloimmunization was found among adult TD TM patients. Early initiation of RBC transfusions, avoidance of splenectomy and extended Rh and K antigen matching, can reduce the incidence of alloimmunization in TD TM patients.

Splenectomy in childhood for non-malignant haematologic disorders - long-term follow-up shows minimal adverse effects

Splenectomy is considered therapeutic in various non-malignant haematologic diseases. Adverse events - specifically infections and thromboembolism - are not extensively documented in the paediatric population, maintaining the concern over risks-versus-benefits of the procedure. We studied a cohort of paediatric haematology patients undergoing splenectomy between 1977 and 2015 to determine short- and long-term complications. We summarised all the patients of the haematology clinic in our major Israeli tertiary centre undergoing splenectomy for therapeutic reasons, capturing infectious and thromboembolic events. The data of 103 patients, comprising 1657 follow-up years, were analysed. The cohort included 33 patients with transfusion-dependent thalassaemia, seven with non-transfusion-dependent thalassaemia, four with sickle-thalassaemia, 41 with hereditary spherocytosis, and 18 with immune thrombocytopenia. Standard presplenectomy vaccinations were noted in most. No typical cases of overwhelming postsplenectomy infection (OPSI) were identified, nor were typical OPSI bacteria isolated. Thalassaemics with central lines were most prone to infection and thrombosis. Beyond this subgroup, thrombotic events were anecdotal. This is the largest study to date to comprehensively analyse infectious and thrombotic complications of childhood splenectomy for the treatment of haematologic diseases. The use of splenectomy appears to be a relatively safe therapeutic option in paediatric patients with proper preoperative vaccination and follow-up care; use of central venous lines or catheters increase the risk in thalassaemic patients and should be avoided if possible.

Multicenter Ozone Study in oldEr Subjects (MOSES): Part 1. Effects of Exposure to Low Concentrations of Ozone on Respiratory and Cardiovascular Outcomes

INTRODUCTION

Exposure to air pollution is a well-established risk factor for cardiovascular morbidity and mortality. Most of the evidence supporting an association between air pollution and adverse cardiovascular effects involves exposure to particulate matter (PM). To date, little attention has been paid to acute cardiovascular responses to ozone, in part due to the notion that ozone causes primarily local effects on lung function, which are the basis for the current ozone National Ambient Air Quality Standards (NAAQS). There is evidence from a few epidemiological studies of adverse health effects of chronic exposure to ambient ozone, including increased risk of mortality from cardiovascular disease. However, in contrast to the well-established association between ambient ozone and various nonfatal adverse respiratory effects, the observational evidence for impacts of acute (previous few days) increases in ambient ozone levels on total cardiovascular mortality and morbidity is mixed.

Ozone is a prototypic oxidant gas that reacts with constituents of the respiratory tract lining fluid to generate reactive oxygen species (ROS) that can overwhelm antioxidant defenses and cause local oxidative stress. Pathways by which ozone could cause cardiovascular dysfunction include alterations in autonomic balance, systemic inflammation, and oxidative stress. These initial responses could lead ultimately to arrhythmias, endothelial dysfunction, acute arterial vasoconstriction, and procoagulant activity. Individuals with impaired antioxidant defenses, such as those with the null variant of glutathione S-transferase mu 1 (GSTM1), may be at increased risk for acute health effects.

The Multicenter Ozone Study in oldEr Subjects (MOSES) was a controlled human exposure study designed to evaluate whether short-term exposure of older, healthy individuals to ambient levels of ozone induces acute cardiovascular responses. The study was designed to test the a priori hypothesis that short-term exposure to ambient levels of ozone would induce acute cardiovascular responses through the following mechanisms: autonomic imbalance, systemic inflammation, and development of a prothrombotic vascular state. We also postulated a priori the confirmatory hypothesis that exposure to ozone would induce airway inflammation, lung injury, and lung function decrements. Finally, we postulated the secondary hypotheses that ozone-induced acute cardiovascular responses would be associated with: (a) increased systemic oxidative stress and lung effects, and (b) the GSTM1-null genotype.

METHODS

The study was conducted at three clinical centers with a separate Data Coordinating and Analysis Center (DCAC) using a common protocol. All procedures were approved by the institutional review boards (IRBs) of the participating centers. Healthy volunteers 55 to 70 years of age were recruited. Consented participants who successfully completed the screening and training sessions were enrolled in the study. All three clinical centers adhered to common standard operating procedures (SOPs) and used common tracking and data forms. Each subject was scheduled to participate in a total of 11 visits: screening visit, training visit, and three sets of exposure visits, each consisting of the pre-exposure day, the exposure day, and the post-exposure day. The subjects spent the night in a nearby hotel the night of the pre-exposure day.

On exposure days, the subjects were exposed for three hours in random order to 0 ppb ozone (clean air), 70 ppb ozone, and 120 ppm ozone, alternating 15 minutes of moderate exercise with 15 minutes of rest. A suite of cardiovascular and pulmonary endpoints was measured on the day before, the day of, and up to 22 hours after, each exposure. The endpoints included: (1) electrocardiographic changes (continuous Holter monitoring: heart rate variability [HRV], repolarization, and arrhythmia); (2) markers of inflammation and oxidative stress (C-reactive protein [CRP], interleukin-6 [IL-6], 8-isoprostane, nitrotyrosine, and P-selectin); (3) vascular function measures (blood pressure [BP], flow-mediated dilatation [FMD] of the brachial artery, and endothelin-1 [ET-1]; (4) venous blood markers of platelet activation, thrombosis, and microparticle-associated tissue factor activity (MP-TFA); (5) pulmonary function (spirometry); (6) markers of airway epithelial cell injury (increases in plasma club cell protein 16 [CC16] and sputum total protein); and (7) markers of lung inflammation in sputum (polymorphonuclear leukocytes [PMN], IL-6, interleukin-8 [IL-8], and tumor necrosis factor-alpha [TNF-α]). Sputum was collected only at 22 hours after exposure.

The analyses of the continuous electrocardiographic monitoring, the brachial artery ultrasound (BAU) images, and the blood and sputum samples were carried out by core laboratories. The results of all analyses were submitted directly to the DCAC.

The variables analyzed in the statistical models were represented as changes from pre-exposure to post-exposure (post-exposure minus pre-exposure). Mixed-effect linear models were used to evaluate the impact of exposure to ozone on the prespecified primary and secondary continuous outcomes. Site and time (when multiple measurements were taken) were controlled for in the models. Three separate interaction models were constructed for each outcome: ozone concentration by subject sex; ozone concentration by subject age; and ozone concentration by subject GSTM1 status (null or sufficient). Because of the issue of multiple comparisons, the statistical significance threshold was set a priori at P < 0.01.

RESULTS

Subject recruitment started in June 2012, and the first subject was randomized on July 25, 2012. Subject recruitment ended on December 31, 2014, and testing of all subjects was completed by April 30, 2015. A total of 87 subjects completed all three exposures. The mean age was 59.9 ± 4.5 years, 60% of the subjects were female, 88% were white, and 57% were GSTM1 null. Mean baseline body mass index (BMI), BP, cholesterol (total and low-density lipoprotein), and lung function were all within the normal range.

We found no significant effects of ozone exposure on any of the primary or secondary endpoints for autonomic function, repolarization, ST segment change, or arrhythmia. Ozone exposure also did not cause significant changes in the primary endpoints for systemic inflammation (CRP) and vascular function (systolic blood pressure [SBP] and FMD) or secondary endpoints for systemic inflammation and oxidative stress (IL-6, P-selectin, and 8-isoprostane). Ozone did cause changes in two secondary endpoints: a significant increase in plasma ET-1 (P = 0.008) and a marginally significant decrease in nitrotyrosine (P = 0.017). Lastly, ozone exposure did not affect the primary prothrombotic endpoints (MP-TFA and monocyte-platelet conjugate count) or any secondary markers of prothrombotic vascular status (platelet activation, circulating microparticles [MPs], von Willebrand factor [vWF], or fibrinogen.).

Although our hypothesis focused on possible acute cardiovascular effects of exposure to low levels of ozone, we recognized that the initial effects of inhaled ozone involve the lower airways. Therefore, we looked for: (a) changes in lung function, which are known to occur during exposure to ozone and are maximal at the end of exposure; and (b) markers of airway injury and inflammation. We found an increase in forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV₁) after exposure to 0 ppb ozone, likely due to the effects of exercise. The FEV₁ increased significantly 15 minutes after 0 ppb exposure (85 mL; 95% confidence interval [CI], 64 to 106; P < 0.001), and remained significantly increased from pre-exposure at 22 hours (45 mL; 95% CI, 26 to 64; P < 0.001). The increase in FVC followed a similar pattern. The increase in FEV₁ and FVC were attenuated in a dose-response manner by exposure to 70 and 120 ppb ozone. We also observed a significant ozone-induced increase in the percentage of sputum PMN 22 hours after exposure at 120 ppb compared to 0 ppb exposure (P = 0.003). Plasma CC16 also increased significantly after exposure to 120 ppb (P < 0.001). Sputum IL-6, IL-8, and TNF-α concentrations were not significantly different after ozone exposure. We found no significant interactions with sex, age, or GSTM1 status regarding the effect of ozone on lung function, percentage of sputum PMN, or plasma CC16.

CONCLUSIONS

In this multicenter clinical study of older healthy subjects, ozone exposure caused concentration-related reductions in lung function and presented evidence for airway inflammation and injury. However, there was no convincing evidence for effects on cardiovascular function. Blood levels of the potent vasoconstrictor, ET-1, increased with ozone exposure (with marginal statistical significance), but there were no effects on BP, FMD, or other markers of vascular function. Blood levels of nitrotyrosine decreased with ozone exposure, the opposite of our hypothesis. Our study does not support acute cardiovascular effects of low-level ozone exposure in healthy older subjects. Inclusion of only healthy older individuals is a major limitation, which may affect the generalizability of our findings. We cannot exclude the possibility of effects with higher ozone exposure concentrations or more prolonged exposure, or the possibility that subjects with underlying vascular disease, such as hypertension or diabetes, would show effects under these conditions.

GFR in Patients with β-Thalassemia Major

BACKGROUND AND OBJECTIVES

Patients with β-thalassemia major (TM) may have tubular dysfunction and glomerular dysfunction, primarily hyperfiltration, based on eGFR. Assessment of GFR based on serum creatinine concentration may overestimate GFR in these patients. This study sought to determine GFR by using inulin clearance and compare it with measured creatinine clearance (Ccr) and eGFR.

DESIGN, SETTING, PARTICIPANTS & MEASUREMENTS

Patients followed up in an Israeli thalassemia clinic who had been regularly transfused for years and treated with deferasirox were included in the study. They were studied by inulin clearance, Ccr, the CKD Epidemiology Collaboration and the Modification of Diet in Renal Disease equations for eGFR, and the Cockcroft-Gault estimation for Ccr. Expected creatinine excretion rate and tubular creatinine secretion rate were calculated.

RESULTS

Nine white patients were studied. Results, given as medians, were as follows: serum creatinine was 0.59 mg/dl (below normal limits); GFR was low (76.6 ml/min per 1.73 m(2)) and reached the level of CKD; Ccr was 134.9 ml/min per 1.73 m(2), higher than the GFR because of a tubular creatinine secretion rate of 30.3 ml/min per 1.73 m(2) (this accounted for 40% of the Ccr); and eGFR calculated by the CKD Epidemiology Collaboration and Modification of Diet in Renal Disease equations and Cockcroft-Gault-estimated Ccr were 133, 141, and 168 ml/min per 1.73 m(2), respectively. These latter values were significantly higher than the GFR, reaching the hyperfiltration range, and indicated that the estimation techniques were clinically unacceptable as a method for measuring kidney function compared with the GFR according to Bland and Altman analyses.

CONCLUSIONS

Contrary to previous reports, patients in this study with TM had normal or reduced GFR. The estimating methods showed erroneous overestimation of GFR and were clinically unacceptable for GFR measurements in patients with TM by Bland and Altman analysis. Therefore, more accurate methods should be used for early detection of reduced GFR and prevention of its further decline toward CKD in these patients.

Thalassemia in Israel: 2012

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Serum CA 125 as a Prognostic Factor in Non-Hodgkin's Lymphoma

Cancer antigen 125 (CA 125) is a glycoprotein expressed in normal tissues originally derived from coelomic epithelia such as peritoneum, pleura, pericardium, fallopian tubes and endometrium. Serum CA 125 levels are elevated in various benign and malignant conditions that involve stimulation of these tissues. Although elevated levels have been reported in patients with non-Hodgkin's lymphoma (NHL), its role as a prognostic factor remained uncertain. In this study, serum CA 125 levels were measured prospectively in 108 consecutive patients with NHL: at diagnosis in 106, in remission in 39 and at relapse in 7. Levels were elevated in 43% at diagnosis. This finding was associated with advanced disease stage, bulky tumors, bone marrow involvement, extranodal disease (in stages III and IV), occurrence of B symptoms, pleural or peritoneal effusions, high serum LDH levels, high serum beta2 microglobulin (beta2-M) levels, elevated International Prognostic Score, poor performance status and partial or no response to treatment. No difference in CA 125 level was found between the indolent and aggressive lymphomas. Serum CA 125 levels at diagnosis had strong association with event-free and overall survival (p = 0.01 and 0.003, respectively), with the patients with increased levels having worse survival. Patients with high CA 125 levels at diagnosis who achieved remission showed a significant decrease in CA 125 levels in remission. In conclusion, CA 125 is not only a reliable marker for staging and assessing tumor activity in NHL, elevated levels are also predictive of decreased survival.

Barriers to education of overseas doctors in paediatrics: a qualitative study in South Yorkshire

OBJECTIVE

To explore the factors that may influence the progress of doctors who come from the Indian subcontinent to train in paediatrics in the UK.

METHODS

Overseas doctors training in paediatrics in Rotherham, Sheffield and Doncaster participated in the study. Focus groups were used to collect data; two focus groups, each with 4-5 participants, were conducted at 6-week intervals. Semistructured, one-to-one interviews were conducted to add more understanding and depth to issues highlighted in the focus groups. The focus groups and interviews were audiotaped; the tapes were transcribed and data were analysed using the Grounded Theory; open codes were formed and concepts identified using microanalysis, and initial theories were built.

RESULTS

Lack of information about the National Health Service (NHS)/Royal Colleges, inappropriate communication skills, difficulties in team working, difficulties in preparing for Royal College examinations, visa and job hunting, and social and cultural isolation were identified as major barriers. Problems arose not only from difficulties with language but also from use of local and colloquial words, different accents and difficulty in communicating sensitive issues. Lack of understanding of role in teams and difficulties in working in multiprofessional setting all contributed to the problems. Cultural differences inside and outside the workplace, and social isolation were also highlighted. Induction programmes, mentoring, awareness of the issues within the teams, and courses in communication specifically directed at overseas doctors were identified as means to overcome these barriers.

CONCLUSIONS

Several intercultural factors were identified that could act as barriers to the progress of overseas doctors training in paediatrics in the UK. Increased awareness of these factors within the teams would be the first step in resolving some of the issues.

Antiphospholipid antibodies may be a new prognostic parameter in aggressive non-Hodgkin's lymphoma

OBJECTIVES

Patients with malignancies have an increased prevalence of antiphospholipid antibodies (APA). The aim of this study was to determine the prevalence of IgG, IgM, and IgA anticardiolipin antibodies (aCL) and anti-beta-2 glycoprotein I antibodies (anti-beta2-GPI) in patients with non-Hodgkin's lymphoma (NHL), and to investigate their clinical and prognostic significance.

METHODS

The study group included 86 patients with NHL. Enzyme-linked immunosorbent assay kits were used to measure the concentrations of aCL and anti-beta2-GPI, and coagulation tests, to measure lupus anticoagulant (LAC) activity. Blood was collected at diagnosis in all patients and at follow-up in 15. Median follow-up time was 1.9 yr.

RESULTS

Elevated APA levels were found in 35 patients (41%) at diagnosis: one patient aCL IgG, five patients aCL IgM, five aCL IgA, one anti-beta2-GPI IgG, 14 anti-beta2-GPI IgM, and 19 anti-beta2-GPI IgA; LAC activity was found in three of 67 patients (4.5%). There was no significant correlation between elevated APA levels and patient's age or sex, disease stage or grade, bone marrow involvement, B symptoms, serum lactate dehydrogenase levels, serum beta2 microglobulin levels, International Prognostic Index (IPI) score, performance status, type of treatment, or response to treatment. There was a correlation between elevated APA and absence of extranodal disease (P = 0.045). A strong negative correlation was found between elevated APA at diagnosis and survival time. Two-year survival was 90 +/- 5% for patients without APA at diagnosis compared with 63 +/- 11% for patients with an elevated APA levels (P = 0.0025). APA added to the predictive value of IPI for event-free and overall survival.

CONCLUSIONS

APA are elevated in 41% of NHL patients at diagnosis and are correlated with shortened survival. Their level may serve as an independent prognostic variable in aggressive NHL.

Human T lymphotropic virus type 1 in a seronegative B chronic lymphocytic leukemia patient

Human T lymphotropic virus type 1 (HTLV-1) is the etiological agent of adult T cell leukemia and HTLV-1-associated myelopathy/tropical spastic paraparesis. HTLV-1 infection in patients with B cell-type chronic lymphocytic leukemia (B-CLL) is rare and has been reported only in areas in which HTLV-1 is endemic. In the present study, we detected HTLV-1 proviral DNA by polymerase chain reaction, using tax primers, in peripheral blood lymphocytes from a B-CLL patient, an immigrant to Israel, where HTLV-1 infection is not endemic. F344 rats injected intravenously with peripheral blood lymphocytes obtained from the patient developed HTLV-1 antibodies. Titers of antibody to HTLV-1 in the rat blood were 1:512 by particle agglutination; enzyme-linked immunosorbent assay and Western blotting were also positive. No antibody against HTLV-1 was demonstrated in the animal model after inoculation of either purified B lymphocytes from the B-CLL patient or peripheral blood mononuclear cells from healthy donors. This is one of the few studies showing the presence of HTLV-1 provirus in T lymphocytes of a B-CLL patient who had multiple infections, and died of salmonella sepsis, and the first report of HTLV-1 antibody induction in an animal model by inoculation of lymphocytes obtained from an HTLV-1-infected B-CLL patient.

Bridging the gap--vocational trainee to senior house officer: a new induction course

OBJECTIVES

The objectives of this course were: to develop an induction course for vocational trainees taking up first SHO posts; to enable new dental SHOs to have enhanced skills from the beginning of the post; to create safe practitioners capable of performing SHO duties; and to assess whether such a course is perceived to be beneficial by the SHOs, their educational supervisors and professional colleagues from medicine, dentistry and nursing.

DESIGN

A 5-day intensive, interactive course was developed and directed by a consultant maxillofacial surgeon, with contributions from a range of professional colleagues to teach appropriate knowledge, skills and attitudes.

SUBJECTS

Trainees completing the VT programme; due to commence SHO posts in the Yorkshire Region.

EVALUATION METHOD

Detailed daily and end of course questionnaires were completed. A post course; in-work evaluation was sought from the trainees, educational supervisors and a range of professional colleagues about the validity of the course.

RESULTS

Daily and end of course evaluations were positive about the perceived importance and relevance of the course. After 6 weeks in post the SHOs continued to place high value on the course as a preparation for hospital practice. Feedback from the supervisors and colleagues indicated that the SHOs were performing well, but the influence of the course on performance could not be determined in this study.

CONCLUSION

It was possible to design and deliver an appropriate induction course, which appeared to meet most of the needs of new dental SHOs. Feedback indicated the need for modification of some aspects of the course.

Myocardial collagen type I and impaired left ventricular function under exercise in hypertrophic cardiomyopathy

BACKGROUND

Transaortic subvalvular myectomy (TSM) reduces left ventricular outflow tract gradient and improves symptoms and working capacity in patients with hypertrophic obstructive cardiomyopathy (HOCM). Nevertheless, TSM does not completely restore normal ventricular function, and some patients complain of symptoms despite optimal surgical results. Abnormal myocardial collagen structure in hypertrophic cardiomyopathy might be an indicator of impaired cardiac function.

METHODS

Nine patients with HOCM were investigated. Myocytic diameter, collagen volume fraction and light absorbance of immunohistochemically stained collagen subtype I and its product (Coll I(prod)) were measured quantitatively in myectomy specimens. Patients underwent symptom-limited bicycle exercise testing with equilibrium radionuclide angiocardiography to determine ejection fraction (EF). Right heart catheterization was performed simultaneously in order to measure pulmonary capillary wedge pressure (PCWP) as a parameter of global ventricular diastolic filling and cardiac index (CI) as a parameter of functional capacity.

RESULTS

Postoperatively, CI increased from 3.1 +/- 0.4 to 5.7 +/- 1.3 l/min/m(2) under exercise. EF was normal at rest (64 +/- 9 %) but did not increase significantly under exercise (66 +/- 14 %). Coll I(prod) (13.62 +/- 7.35 Vv%(prod)) correlated inversely with EF under exercise (r = -0.64; p = 0.05). PCWP increased under exercise from 8 +/- 2 mmHg at rest to 22 +/- 9 mmHg (p = 0.01). Coll I(prod) correlated with PCWP under exercise (r = 0.90; p = 0.001).

CONCLUSIONS

Increased collagen subtype I is a predictor of diastolic as well as systolic dysfunction under exercise in patients with HCM after successful TSM.

Sjögren's syndrome associated T cell large granular lymphocyte leukemia: a possible common etiopathogenesis

Two patients with primary Sjögren's syndrome and T cell large granular lymphocyte (LGL) leukemia are described. One patient had evidence of T cell LGL salivary gland infiltration, suggesting a possible common etiopathogenesis for these 2 conditions.

Teaching in the new NHS: the specialised ward based teacher

OBJECTIVES

To evaluate the effects of introducing specialised ward based teachers (WBTs) who had a broad remit to improve third year medical undergraduates' clinical experience.

DESIGN

Quantitative and qualitative methods including interviews with WBTs, participating consultants and SIFT co-ordinator; student questionnaire and evaluations; analysis of Objective Structured Clinical Examination (OSCE) scores to ascertain if exposure to WBTs affected OSCE scores.

SETTING

Two university teaching hospitals.

PARTICIPANTS

Third year undergraduate medical students from one school of medicine; four WBTs; 25 consultants; SIFT co-ordinator.

MAIN OUTCOME MEASURES

Student evaluations. Student questionnaires. Student OSCE scores. Interview data.

RESULTS

WBTs had a demonstrable effect on student performance in OSCE examinations. 94% of students either agreed or strongly agreed that WBTs had helped them develop their examination skills and 87% either agreed or strongly agreed that WBTs had helped them develop their history taking skills. Interview data indicated that the consultants and SIFT co-ordinator considered that WBTs made an important contribution to clinical teaching.

CONCLUSIONS

This study suggests that specialised WBTs are one way to manage clinical experience and enhance learning of undergraduate medical students. As clinical teaching moves into earlier parts of the undergraduate curriculum and into the community there is potential for this role to be developed.

Response of brown treesnakes (Boiga irregularis) to mammalian blood: whole blood, serum, and cellular residue

Brown treesnakes (Boiga irregularis) responded with more tongue flicks to blood (from rabbits, rats, and mice) than to water. When rat blood was centrifuged at 3,500 rpm for 5 min, separating serum from cellular residue, snakes responded strongly to serum but not to cellular residue.

Digital storage phosphor chest radiography: an ROC study of the effect of 2K versus 4K matrix size on observer performance

PURPOSE

To compare observer performance in the detection of abnormalities on 1,760 x 2,140 matrix (2K) and 3,520 x 4,280 matrix (4K) digital storage phosphor chest radiographs.

MATERIALS AND METHODS

One hundred sixty patients who underwent dedicated computed tomography (CT) of the thorax were prospectively recruited into the study. Posteroanterior and lateral computed radiographs of the chest were acquired in each patient and printed in 2K and 4K formats. Six radiologists independently analyzed the hard-copy images and scored the presence of parenchymal (opacities </=2 cm, opacities >2 cm, and subtle interstitial), mediastinal, and pleural abnormalities on a five-point confidence scale. With CT as the reference standard, observer performance tests were carried out by using receiver operating characteristic (ROC) analysis.

RESULTS

Analysis of averaged observer performance showed 2K and 4K images were equally effective in detection of all three groups of abnormalities. In the detection of the three subtypes of parenchymal abnormalities, there were no significant differences in averaged performance between the 2K and 4K formats (area below ROC curve [A(z)] values: opacities </=2 cm, 0.62 +/- 0.056 [standard error] and 0.59 +/- 0.045; opacities >2 cm, 0.86 +/-.025 and 0.85 +/- 0.030; subtle interstitial abnormalities, 0.73 +/- 0.041 and 0.72 +/- 0.041). Averaged performance in detection of mediastinal and pleural abnormalities was equivalent (A(z) values: mediastinal, 0.70 +/- 0.046 and 0.73 +/- 0.033; pleural, 0.85 +/- 0.032 and 0.86 +/- 0.033).

CONCLUSION

Observer performance in detection of parenchymal, mediastinal, and pleural abnormalities was not significantly different on 2K and 4K storage phosphor chest radiographs.

Linkage analysis for major histocompatibility complex-related genetic susceptibility in familial chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) shows evidence of familial aggregation, but the genetic basis is poorly understood. The existence of a linkage between HLA and Hodgkin lymphoma, another B-cell disorder, coupled with the fact that CLL is frequently associated with autoimmune disease, led to the question of whether the major histocompatibility complex (MHC) region is involved in familial cases of CLL. To examine this proposition, 5 microsatellite markers on chromosome 6p21.3 were typed in 28 families with CLL, 4 families with CLL in association with other lymphoproliferative disorders, and 1 family with splenic lymphoma with villous lymphocytes. There was no evidence of linkage in these families to chromosome 6p21.3. The best estimates of the proportions of sibling pairs with CLL that share 0, 1, or 2 MHC haplotypes were not significantly different from the null expectation. This implies that genes within the MHC region are unlikely to be the major determinants of familial CLL. (Blood. 2000;96:3982-3984)

Benefiting from clinical experience: the influence of learning style and clinical experience on performance in an undergraduate objective structured clinical examination

OBJECTIVE

To assess the relationship between clinical experience, learning style and performance in an objective structured clinical examination (OSCE) in medical students at the end of their first clinical year.

DESIGN

Prospective study of undergraduate students taking an OSCE examination at the end of their first clinical year.

SUBJECTS

194 undergraduate medical students (95 male).

MAIN OUTCOME MEASURES

Performance in the OSCE examination, the Entwhistle Learning Style Inventory1 and a composite self-reported score of clinical activity during the students first clinical year.

RESULTS

Performance in the OSCE examination was related to well-organized study methods but not to clinical experience. A significant relationship between clinical experience and organized deep-learning styles suggests that knowledge gained from clinical experience is related to learning style.

CONCLUSIONS

The relationship between clinical experience and student performance is complex. Well-organized and strategic learning styles appear to influence the benefits of increased clinical exposure. Further work is required to elucidate the most beneficial aspects of clinical teaching.

Cytokines IL-1beta, IL-2, IL-6, IL-8, MCP-1, GM-CSF and TNFalpha in patients with epithelial ovarian cancer and their relationship to treatment with paclitaxel

In vitro work suggests that cytokines may be important modulators of the cytotoxic effects of paclitaxel and subsequent drug resistance. This has been investigated in vivo in patients with ovarian cancer by ELISA. There was consistently elevated expression of IL-6 and IL-8 but not MCP-1, IL-1beta, IL-2, GM-CSF or TNFalpha. Peritoneal fluid concentrations of IL-6, IL-8 and MCP-1 were two to three logs greater than serum concentrations. Elevated concentrations of IL-6 correlated with a poor final outcome (P = 0.039), and increased IL-6 and IL-8 correlated with a poor initial response to chemotherapy (P = 0.041 and P = 0.041, respectively). There was a relatively clear pattern of change in all three cytokines. In serum, IL-6, IL-8 and MCP-1 decreased with the administration of steroids prior to paclitaxel, and increased in the 24 h after paclitaxel. Postoperative drainage fluid was relatively acellular, preventing flow-cytometric analysis of epithelial cells for apoptosis, but suggested activation of T cells by paclitaxel. IL-6 and IL-8 appear to be of prognostic importance in epithelial ovarian cancer. Treatment with paclitaxel is associated with an increase in expression of a limited number of cytokines in patients with ovarian cancer, notably IL-6, IL-8 and MCP-1.

Clinical and chest radiographic findings among persons with sputum culture positive for Mycobacterium gordonae: a review of 19 cases

STUDY OBJECTIVES

To describe the clinical and radiographic findings associated with growth of Mycobacterium gordonae in cultured sputum and to determine the proportion of cases that fulfill criteria for nontuberculous mycobacterial pulmonary disease as established by the American Thoracic Society.

DESIGN

A retrospective review of charts and radiographs of all patients from whom M gordonae was isolated from sputum cultures between November 1996 and June 1998.

SETTING

University-affiliated Veterans Affairs hospital.

PATIENTS

Nineteen patients were identified with sputum culture positive for M gordonae. All patients had a chest radiograph within 1 month of sputum culture.

RESULTS

Sixteen patients (84%) had suppressed local and/or general immunity. Sixteen patients (84%) had respiratory symptoms, weight loss, fever, or night sweats as an indication for chest radiography. Seventeen patients (89%) had abnormal chest radiographs; however, no typical radiographic pattern was observed. No patient met diagnostic criteria for nontuberculous mycobacterial pulmonary disease as delineated by the American Thoracic Society. All patients with abnormal chest radiographs and/or respiratory symptoms ultimately had alternative explanations for their pulmonary disease.

CONCLUSIONS

There is a broad spectrum of chest radiographic findings among persons with sputum culture positive for M gordonae, arguing against the presence of a characteristic chest radiograph in this patient population. M gordonae is usually a nonpathogenic colonizing organism, even among persons with local or general immune suppression and abnormal chest radiograph findings.

Linkage analysis for ATM in familial B cell chronic lymphocytic leukaemia

B cell chronic lymphocytic leukaemia (CLL) shows evidence of familial aggregation, but the inherited basis is poorly understood. Mutations in the ATM gene have been demonstrated in CLL. This, coupled with a possibly increased risk of leukaemia in relatives of patients with Ataxia Telangiectasia, led us to question whether the ATM gene is involved in familial cases of CLL. To examine this proposition we typed five markers on chromosome 11q in 24 CLL families. No evidence for linkage between CLL and ATM in the 24 families studied and the best estimates of the proportion of sibling pairs that share no, one or both haplotypes at ATM were not different from their null expectations. This would imply that ATM is unlikely to make a significant contribution to the three-fold increase in risk of CLL seen in relatives of patients.

Sublingual therapy for cobalamin deficiency as an alternative to oral and parenteral cobalamin supplementation

Effectiveness of sublingual cobalamin-replacement therapy was studied in 18 people with cobalamin deficiency. Administration was efficacious and convenient, and compliance was high.

Pulmonary parenchymal manifestations of mitral valve disease

Pulmonary parenchymal manifestations of mitral valve disease are the result of either pulmonary venous hypertension in mitral stenosis or abnormal regurgitant flow into pulmonary veins in mitral insufficiency. Typical radiographic findings in mitral stenosis include pulmonary vascular cephalization; interstitial, perivascular, and occasionally alveolar pulmonary edema; diffuse alveolar hemorrhage; hemosiderosis; and pulmonary ossification. Signs of interstitial pulmonary edema are frequently visible and include septal lines. Radiographic findings in diffuse alveolar hemorrhage consist of diffuse, confluent acinar or ground-glass areas of increased opacity, often sparing the peripheral parenchyma and creating the so-called window frame effect. Hemosiderosis is characterized by small, ill-defined nodules or by coarse reticular areas of increased opacity with a bias for the middle and lower lung regions. Ossification manifests as densely calcified, 1-5-mm nodules, mainly in the middle and lower lungs, with a tendency for confluence and the occasional presence of trabeculae. Imaging findings in mitral regurgitation depend on the acuteness of the disease. The most common parenchymal manifestations of acute mitral regurgitation are symmetric alveolar and interstitial pulmonary edema with indistinct, engorged pulmonary vessels and cephalized blood flow. Familiarity with these manifestations can expedite diagnosis, particularly in rare cases of unsuspected mitral valve disease.

Impaired T-lymphocyte function in B-chronic lymphocytic leukaemia as measured by the local xenogeneic graft-versus-host reaction

The immunological dysfunction observed in B-chronic lymphocytic leukaemia (B-CLL) is often related to T-lymphocyte incompetence. The local xenogeneic graft-vs.-host reaction (XGVHR), an assay to evaluate T-lymphocyte function, was performed in 112 untreated B-CLL patients. The XGVHR results significantly correlated with clinical parameters: 37.1% of the patients in the stable phase (Rai stage 0-1-2) and only 13.3% of the patients in the progressive phase (Rai stage 3-4) had positive XGVHR results. Patients with negative results had a higher number and percentage of lymphocytes (25,247 vs. 17,071/microliter and 75.9% vs. 65.6%, respectively), much lower T/B lymphocyte ratio (0.37 vs. 0.93), higher WBC count (30,977 vs. 23,458/microliter), lower platelet count (158,068 vs. 181,684/microliter) and lower levels of IgA and IgM (115.6 vs. 200.5 mg/dl and 80.4 vs. 124.3 mg/dl, respectively) compared to those with positive results. Among those with negative XGVHR results, a higher mortality rate was found in those who had infections compared with those who did not (73.7% vs. 9.1%). In conclusion, the XGVHR assay significantly correlates with important characteristics of B-CLL and may be useful in the clinical evaluation of B-CLL patients.

Diagnosis, pathogenesis and treatment of the myeloproliferative disorders essential thrombocythemia, polycythemia vera and essential megakaryocytic granulocytic metaplasia and myelofibrosis

According to strict clinical, hematological and morphological criteria, the Philadelphia (Ph) chromosome negative chronic myeloproliferative disorders essential thrombocythemia (ET), polycythemia vera (PV), and agnogenic myeloid (megakaryocytic/granulocytic) metaplasia (AMM) or idiopathic myelofibrosis (IMF) are three distinct disease entities with regard to clinical manifestations, natural history and outcome in terms of life expectancy. As clonality studies have clearly demonstrated that fibroblast proliferation in AMM, as well as in many other conditions such as advanced stages of Ph(+)-essential thrombocythemia, Ph(+)-granulocytic leukemia, and Ph(-)-polycythemia vera, is polyclonal indicating that myelofibrosis is secondary to the megakaryocytic granulocytic metaplasia in these various conditions, AMM is illogically labeled as IMF. As abnormal megakaryocytic granulocytic metaplasia is the essential feature preceding the early prefibrotic stage of AMM, the term essential megakaryocytic granulocytic metaplasia (EMGM) can readily be used to characterize this condition more appropriately at the biological level. Clinical, hematological and morphological characteristics, in particular megakaryocytopoiesis and bone marrow cellularity, reveal diagnostic features, which enable a clear-cut distinction between ET, PV and EMGM or classical IMF. The characteristic increase and clustering of enlarged megakaryocytes with mature cytoplasm and multilobulated nuclei and their tendency to cluster in a normal or only slightly increased cellular bone marrow represent the hallmark of ET. The characteristic increase and clustering of enlarged mature and pleiomorphic megakaryocytes with multilobulated nuclei and proliferation of erythropoiesis in a moderate to marked hypercellular bone marrow with hyperplasia of dilated sinuses are the specific diagnostic features of untreated PV. EMGM, including the early prefibrotic stages as well as the various myelofibrotic stages of classical IMF appear to be a distinct neoplastic dual proliferation of abnormal megakaryopoiesis and granulopoiesis. The histopathology of the bone marrow in prefibrotic EMGM and in classical IMF is dominated by atypical, enlarged and immature megakaryocytes with cloud-like immature nuclei, which are not seen in ET and PV at diagnosis and during follow-up. Myelofibrosis in ET, PV and EMGM is graded into: no reticulin fibrosis (MF0), early reticulin fibrosis (MF1), advanced reticulin sclerosis with minor or moderate collagen fibrosis (MF2) and advanced collagen fibrosis with osteosclerosis (MF3). Myelofibrosis is not a feature of ET at diagnosis and during long-term follow-up. Myelofibrosis may be present in a minority of PV-patients at diagnosis and usually becomes apparent during long-term follow-up in the majority of PV-patients. Myelofibrosis secondary to the abnormal megakaryocytic and granulocytic myeloproliferation constitutes a prominent feature in the majority of EMGM/IMF at time of diagnosis and usually progresses more or less rapidly during the natural history of the disease. Life expectancy is normal in ET, normal during the 1st ten years and compromised during the 2nd ten years follow-up in PV, but significantly shortened in the prefibrotic stage of EMGM as well as in the various myelosclerotic stages of classical IMF. First line treatment options in prospective randomized clinical trials of newly diagnosed MPD-patients are control of platelet function with low-dose aspirin versus reduction of platelet count with anagrelide, interferon or hydroxyurea in ET; control of platelet and erythrocyte counts by interferon alone versus bloodletting plus hydroxyurea on indication in PV; interferon versus no treatment in the early stages of EMGM; a wait and see strategy in the fibrotic stages of EMGM or classical IMF with favorable prognostic factors, and bone marrow transplantation in classical IMF with poor prognostic factors at presentation or during short-term follow-up.