Impact of an AI software on the diagnostic performance and reading time for the detection of cerebral aneurysms on time of flight MR-angiography

PURPOSE

To evaluate the impact of an AI-based software trained to detect cerebral aneurysms on TOF-MRA on the diagnostic performance and reading times across readers with varying experience levels.

METHODS

One hundred eighty-six MRI studies were reviewed by six readers to detect cerebral aneurysms. Initially, readings were assisted by the CNN-based software mdbrain. After 6 weeks, a second reading was conducted without software assistance. The results were compared to the consensus reading of two neuroradiological specialists and sensitivity (lesion and patient level), specificity (patient level), and false positives per case were calculated for the group of all readers, for the subgroup of physicians, and for each individual reader. Also, reading times for each reader were measured.

RESULTS

The dataset contained 54 aneurysms. The readers had no experience (three medical students), 2 years experience (resident in neuroradiology), 6 years experience (radiologist), and 12 years (neuroradiologist). Significant improvements of overall specificity and the overall number of false positives per case were observed in the reading with AI support. For the physicians, we found significant improvements of sensitivity on lesion and patient level and false positives per case. Four readers experienced reduced reading times with the software, while two encountered increased times.

CONCLUSION

In the reading with the AI-based software, we observed significant improvements in terms of specificity and false positives per case for the group of all readers and significant improvements of sensitivity and false positives per case for the physicians. Further studies are needed to investigate the effects of the AI-based software in a prospective setting.

Gender differences in homocysteine concentrations, a population-based cross-sectional study

BACKGROUND AND AIMS

High concentrations of homocysteine are considered a risk factor for atherosclerosis and coronary artery disease. The aim of this study was to assess whether or not there are gender differences in the plasma concentrations of homocysteine.

METHODS AND RESULTS

Data were collected from medical records of individuals examined at a screening center in Israel between the years 2000-2014. Cross sectional analysis was carried out on 9237 men and 4353 women. Mean (SD) age of the study sample was 48.4 (9.7) and 47.7 (9.7) years for men and women respectively. Average homocysteine concentrations were 12.6 (5.9) and 9.6 (3.2) μmol/L in men and women respectively (p < 0.001). Prevalence of homocysteine concentrations above 15 μmol/L was found to be significantly higher in men than in women; 15.5% vs 3.9% respectively (p < 0.001). Low concentrations of vitamin (B12 < 200 pmol/L) and low concentrations of folate (<12 nmol/L) were found to be significantly higher in men than in women 20.4% vs. 16.0% and 18.5% vs. 10.8% respectively. Compared to women, men had a significantly higher odds ratio (95% CI) of having homocysteine concentrations above 15 μmol/L: non adjusted model, 4.47 (3.80-5.26); adjusted model for age, smoking status, body mass index, diabetes mellitus, kidney function and low serum concentrations of vitamin B12 and folate, 3.44 (2.89-4.09).

CONCLUSION

Plasma homocysteine concentrations are higher in men than in women. This may be a contributing factor to gender differences for developing atherosclerosis and coronary artery disease.

A multisensor implant for continuous monitoring of intracranial pressure dynamics

In humans, intracranial pressure (ICP) is not only influenced by pathology, but also by orientation in space and body movements. Therefore, it is proposed to measure ICP dynamics and body acceleration simultaneously. An algorithm for acceleration analysis was developed to monitor orientation in space and allow more accurate examination of ICP dynamics during quiet periods. For continuous monitoring, an implant was developed and wireless data transmission was implemented; this prototype was successfully tested in five pigs. Hydrocephalus with increased ICP was experimentally induced in the animals using a surgical kaolin infusion. This model of porcine pathology was then tested with the implant with the aim for eventual use in humans. ICP dynamics and 2D-acceleration data were simultaneously recorded for up to two weeks. This study allowed 24-h monitoring and provided analysable data on porcine ICP dynamics with humanlike ICP waves, the so called B- and P-waves. Results show that acceleration often had a stronger influence on ICP than the amplitudes of the physiological ICP characteristics. With test animals in a standing position, without obvious body movement, ICP varied to an extent that made the characteristic ICP waves difficult to identify. These data allow us to conclude that analysis of both ICP and acceleration may be essential for autonomous implants.

Long-term performance of a CE-approved telemetric intracranial pressure monitoring

Telemetric intracranial pressure (ICP) monitoring has been a challenge throughout several decades. Major obstruction was to minimize zero drift of absolute pressure sensors. A new promising product demonstrating in-vitro excellent long-term stability has been tested for its reliability in an animal model with a follow-up of up to 2 years. In "minipigs" sub-dural (Raumedic-STel®, Helmbrechts Germany) and intraparenchymal (Raumedic-PTel®) telemetric ICP probes have been inserted. Standard ICP probes (Raumedic Neurovent P®) served as controls. In regular intervals of 3 months the telemetrically and conventionally measured ICP have been compared. For each control a new conventional ICP probe has been inserted frontally to the telemetric device in the generalized anesthetized minipigs, resulting in overall 38 comparisons. Bland-Altman-plots, Chi2-tests and matched pair T-tests (significance level < 0.05) were used for data-analysis. The zero-shift was -1.7 ± 7.6 mm Hg (limits of agreement: 4.4 ± 1.9 mm Hg) and -3.0 ± 6.0 mm Hg (limits of agreement: 3.6 ± 2.6 mm Hg) in STel and PTel respectively meeting well the devices specification of ± 2 mm Hg drift per year. The reliability of both telemetric probes has been proved as quite comparable (p=0.2). These new telemetric ICP probes demonstrate reliable data during at least the first 6 months after implantation.

Severe digital ischemia–a presenting symptom of malignancy–associated antiphospholipid syndrome

The association of the antiphospholipid syndrome with malignancy has been extensively reported. Raynaud’s phenomenon has also been reported to be associated with various malignancies. In this report, we describe two patients who presented with severe digital ischemia mimicking Raynaud’s phenomenon. The patients were found to have antiphospholipid syndrome, and upon extensive evaluation, a diagnosis of a malignancy was made. This report highlights the importance of malignancy workup in patients with severe digital ischemia associated with antiphospholipid syndrome.

Cross-reactive epitopes on beta2-glycoprotein-I and Saccharomyces cerevisiae in patients with the antiphospholipid syndrome

Anti-Saccharomyces cerevisiae antibodies (ASCA), directed against the phosphopeptidomannan (PPM) part of the cell wall of the yeast, have been identified as an important and specific serological marker for Crohn's disease. We evaluated the prevalence and properties of ASCA in APS patients. Thirty-one out of 155 APS patients tested positive for ASCA (20.0%), compared to 5.0% in healthy controls (P < 0.05). The presence of ASCA was not associated with any specific manifestation of APS. The ASCA found to be the population of anti-beta2GPI antibodies (Abs). Affinity purified anti-beta2GPI from ASCA-positive sera on a beta2GPI column, bound specifically the PPM, as shown by direct binding and competition assays (95-98%). The PPM inhibited differentially the anti-beta2GPI binding to beta2GPI. Since the anti-beta2GPI anti-PPM could bind only native form of beta2GPI and not the recombinant form, we assume that these specific anti-beta2GPI subpopulations of Abs are directed to the glycosylated site of the molecule. In conclusion, a subpopulation of anti-beta2GPI is specific to the glycosylated site of the beta2GPI molecule that cross-reacts with PPM.

Clusters of disease manifestations in patients with antiphospholipid syndrome demonstrated by factor analysis

The antiphospholipid syndrome (APS) is now recognized as a multi-system disease, the clinical expression of which may include various target-organs involvements. Despite the reported heterogeneity in clinical presentation of APS, the interrelations between various manifestations of the disease has not yet been studied. We evaluated the principle associations between a variety of clinical manifestations in APS patients, applying factor analysis. Two-hundred and forty-six APS patients were studied. The following disease manifestations were used for the factor analysis: recurrent fetal loss, intrauterine growth restriction (IUGR), venous and arterial thrombosis, cardiac valves thickening/dysfunction, valvular vegetations, stroke, epilepsy, migraine, arthritis, livedo reticularis, thrombocytopenia, leukopenia and autoimmune hemolytic anemia (AIHA). The results were further analysed in relation to sex and to primary APS versus APS associated with SLE. Five factors were derived, which accounted for 59.7% of the variance of the matrix. Factor 1 (which explained 18.5% of variance of the original matrix) represented the association between cardiac valves abnormalities, livedo reticularis and AIHA. Factor 2 (13.8% of variance) represented association between arthritis, thrombocytopenia and leukopenia. Factor 3 (10.3% of variance) represented an association between recurrent fetal loss and IUGR. Factor 4 (9.3% of variance) represented inverse correlation between arterial and venous thrombosis. Factor 5 (7.8% of variance) represented an association between epilepsy and migraine. Application of factor analysis revealed specific clusters of cardiac, cutaneous, hematological and neurological manifestations. Our result also point to a possible divergence of arterial and venous thrombotic tendency. Awareness of these patterns might give us a better understanding of the disease.

Autoimmune hemolytic anaemia in the antiphospholipid syndrome

Antiphospholipid syndrome (APS) is a multisystem disease with recurrent thrombosis in the presence of antiphosphlipid antibodies, which may include cardiac, neurological, gastrointestinal, hematologic or cutaneous manifestations. The occurrence of autoimmune hemolytic anaemia (AIHA) in APS has not been well established. The purpose of this study was to review the occurrence of AIHA in patients with APS and its relation to other disease manifestations. Three-hundred and eight patients with APS from seven medical centers in Israel, Serbia and the Slovac Republic were included and evaluated for associations between AIHA and various manifestations of APS. AIHA was documented in 32 patients (10.4%). The odds ration for AIHA was increased in the presence of anticardiolipin antibodies and livedo reticularis (5.4 and 7.8, respectively). There was a highly significant association between AIHA and cardiac valvular vegetations and thickening (P < 0.0001), arterial thrombosis (P < 0.02), livedo reticularis (P < 0.0001) and CNS signs of epilepsy or chorea (P < 0.02 and P < 0.03, respectively). Thus, APS patients with AIHA are at risk of developing these manifestations, and should therefore be investigated for them. In addition, the occurrence of AIHA may define a subgroup of patients with a significant risk for subsequent development of SLE.

Anti-Saccharomyces cerevisiae antibodies in Behçet's disease--a familial study

OBJECTIVE

To evaluate the rate and clinical correlations of antibodies against saccharomyces cerevisiae (ASCA) among healthy family members of patients with Behçet's disease (BD).

METHODS

Twenty-one BD patients and 52 healthy family members (HFM) were studied. Data from medical files and from patients' interviews was collected, regarding the entire spectrum of disease manifestations. Each family member was personally interviewed and a questionnaire composed of BD symptoms and their temporal relation was compiled. IgA- and IgG-ASCA levels, determined by ELISA, were studied in all BD patients and their family members, the results were compared to a group of 23 healthy controls (HC).

RESULTS

Eight (38.1%) BD patients were ASCA positive, compared to five among HFM (9.6%) and none among healthy unrelated controls (p=0.001). Mean IgG and IgA-ASCA levels were significantly higher in BD patients compared with HFM and HC groups (p = 0.002 and p = 0.03, respectively). No correlation was found between positive ASCA tests and any of BD-related manifestations. Mean IgG-ASCA levels were significantly lower in HFM compared to BD patients (p = 0.03), yet IgA-ASCA levels were similar in HFM and BD. Mean IgG and IgA-ASCA levels were higher in HFM compared with healthy unrelated controls (p=0.09 and p=0.03). No difference was found in ASCA rates between relatives of BD patients who had positive or negative ASCA tests, or between spouses of BD patients and genetically related relatives. In HFM with recurrent oral ulcers there was a positive correlation between titers of IgA-ASCA and the yearly number of oral ulcers episodes (p = 0.01), and mean ulcers healing time (p = 0.01). IgG-ASCA titers correlated with yearly number of aphtae episodes (p = 0.03).

CONCLUSION

The results of this study confirm our previous observation on a high prevalence of ASCA in BD. ASCA levels are also increased in healthy family members of BD patients, and are probably influenced by genetic as well as environmental factors. ASCA in HFM were significantly associated with a more severe oral ulcer disease. The role of ASCA as a marker for predisposition to develop future BD remains to be evaluated.

Overlapping humoral autoimmunity links rheumatic fever and the antiphospholipid syndrome

OBJECTIVE

Rheumatic fever (RF) and the antiphospholipid syndrome (APS) are autoimmune diseases that share similar cardiac and neurological pathologies. We assessed the presence of shared epitopes between M protein, N-acetyl-beta-D-glucosamine (GlcNAc) and beta2 glycoprotein-I (beta2GPI), the pathogenic molecules engaged in these autoimmune conditions.

METHODS

Sera from the APS patients were affinity-purified on beta2GPI and beta2GPI-related peptide columns. Sera from RF patients were affinity-purified on protein G column. The beta2GPI and M protein-related peptides were prepared by conventional solid-phase peptide synthesis. The enzyme-linked immunosorbent assay direct binding and inhibition studies were performed on the RF and APS sera for the presence, and cross-reactivity, of antibodies against beta2GPI, beta2GPI-related peptides, streptococcal M protein, M-derived peptides and GlcNAc.

RESULTS

Antibodies (Abs) to beta2GPI were found in 24.4% of 90 RF patients. Antibodies against various beta2GPI-related peptides were found in 1.1-36.7% of the patients. The immunoglobulin G sera from RF patients possessed significant anti-beta2GPI activity, while sera from APS patients contained a considerable anti-streptococcal M protein as well as anti-GlcNAc activity. Furthermore, affinity-purified anti-beta2GPI and anti-beta2GPI-related peptide Abs from APS patients cross-reacted with streptococcal M protein and M5 peptide, while beta2GPI and beta2GPI-related peptides inhibited anti-streptococcal M protein activity from RF patients. The results were confirmed by immunoblot analyses. The beta2GPI also inhibited anti-GlcNAc activity from APS patients with chorea.

CONCLUSIONS

The results of our study, showing a considerable overlap of humoral immunity in RF and APS, support a hypothesis that common pathogenic mechanisms underlie the development of cardiac valve lesions and Central Nervous System abnormalities in both diseases.

Livedo reticularis is a marker for predicting multi-system thrombosis in antiphospholipid syndrome

OBJECTIVE

Livedo reticularis (LR) is a skin vasculopathy that has been frequently described in patients with anti-phospholipid syndrome (APS) and reported to be present in association with valvular heart pathology and strokes (i.e. Sneddon's syndrome).

METHODS

In a cohort of APS patients we investigated the possible association of LR with various clinical aspects of APS such as pregnancy morbidity, central nervous system (CNS) and cardiac manifestations.

RESULTS

Livedo reticularis was found in 50/308 (16%) of APS patients, and there was a significant association with cerebrovascular accidents (CVA), migraines and epilepsy (p = 0.01, 0.002, and 0.02 respectively). A similar association was also detected between LR, and the presence of cardiac valve thickening and vegetations (p = 0.001). No association with venous thrombosis, recurrent fetal loss, IUGR or toxemia was found.

CONCLUSION

Livedo reticularis is a frequent cutaneous manifestation in patients with APS. Its high association with cardiac and CNS thrombosis may suggest that LR-APS patients compose a subset at higher risk for thrombosis, and thus may require a closer follow-up and a more aggressive anticoagulation.

Close association between valvar heart disease and central nervous system manifestations in the antiphospholipid syndrome

BACKGROUND

Heart valves lesions and central nervous system involvement are among the most common manifestations of the antiphospholipid syndrome (APS).

OBJECTIVE

To evaluate possible interrelations between these manifestations in a large group of APS patients.

METHODS

284 APS patients were evaluated retrospectively, 159 of whom had primary APS. Cardiac-CNS associations were determined for the entire study population, and for subgroups of patients with primary APS or APS associated with systemic lupus erythematosus (SLE).

RESULTS

Significant associations where found between cardiac vegetations and epilepsy (p < 0.02), and between cardiac valve thickening or dysfunction and migraine (p = 0.002). Borderline association was found between valvar vegetations and migraine (p = 0.09). A significant association was also found between all valvar lesions and stroke or transient ischaemic attacks. Subanalyses showed that patients with primary APS had significant associations between cardiac valve pathology and all CNS manifestations, while patients with APS associated with SLE had no such associations.

CONCLUSIONS

The study suggests potential differences in biological behaviour between primary APS and APS associated with SLE. The presence of cardiac valve pathology may be a risk factor for several types of CNS involvement in PAPS.

Prevalence and clinical correlations of antibodies against six beta2-glycoprotein-I-related peptides in the antiphospholipid syndrome

Two-hundred ninety five patients with the antiphospholipid syndrome (APS) were studied for the presence of antibodies against six anti-beta2GPI-related peptides Abs. The prevalence of a wide spectrum of clinical and laboratory parameters of APS was evaluated in all patients, and correlated with the presence of each anti-beta2GPI peptide antibody. The rates of the various antipeptides Abs ranged from 18.0 to 63.7%. Altogether, 87.1% of the patients had antibody reactivity against at least one of the six beta2GPI-related peptides. A high degree of simultaneous reactivity against several beta2GPI-peptides was found. Positive and negative correlations were found between several antipeptides Abs and the rates of thrombosis and fetal loss. Our results point to a heterogeneous activity of antiphospholipid Abs in APS patients, directed, often concurrently, against various epitopes of the beta2GPI molecule. Evaluation of APS patients for the presence of specific antipeptides Abs may be of a value in predicting the risk for future thrombotic and obstetrical complication, as well as for specific therapeutic purposes.

TNFalpha DNA vaccination prevents clinical manifestations of experimental antiphospholipid syndrome

Naked DNA encoding TNFalpha was introduced to BALB/c mice with experimental antiphospholipid syndrome (APS) induced by beta2GPI. Administration of naked DNA encoding TNFalpha resulted in the generation of immunological memory to its gene product, associated with elevated circulating anti-TNFalpha antibodies. Enriched IgG fraction of the mouse anti-TNFalpha was biologically active since it prevented endothelial cell activation by TNFalpha e.g., inhibition of monocyte adhesion to activated endothelial cells (HUVEC). Mice immunized with beta2GPI, vaccinated with TNFalpha DNA at an early stage of disease development, showed decreased titres of circulating anti-beta2GPI antibodies as compared to the group of mice vaccinated with a control naked DNA. The reduction of antiphospholipid antibody production was followed by amelioration of the foetal loss, increased platelet count to normal values as well as normalization of the prolonged aPTT. APS mice which were introduced to the TNFalpha DNA vector at a later stage of the disease development, showed less improvement in their clinical manifestations. The current study suggests a way in which a DNA vaccine can be employed for induction of a protective immunity in experimental APS.

10th International Congress on Antiphospholipid Antibodies--summary

The 10th International Congress on Antiphospholipid Antibodies (Sicily, Italy, September 29-October 3, 2002) (Fig. 1) provided enlightening aspects on the recent developments in antiphospholipid syndrome (APS) and antiphospholipid antibodies in more than 150 lectures and posters. Researchers from all aspects of medicine attended the meeting, implicating the systemic characteristics of APS. The important breakthroughs are summarized.

Anti-Saccharomyces cerevisiae antibodies--a novel serologic marker for Behçet's disease

OBJECTIVE

To evaluate the prevalence and clinical correlations of antibodies against Saccharomyces cerevisiae (ASCA) among patients with BD.

METHODS

Twenty-seven BD patients were studied. Data from medical files and from patients' interviews was collected, regarding the entire spectrum of disease manifestations, and a severity score was calculated for each patient. IgA- and IgG-ASCA levels, determined by ELISA, were studied in all BD patients and in three control groups: patients with recurrent aphthous stomatitis (RAS), systemic lupus erythematosus (SLE) and healthy volunteers.

RESULTS

Thirteen BD patients (48.1%) were ASCA-positive, compared to one patient in each control group (10%, p = 0.01). The mean value of IgG-ASCA in the BD patients was 20.7 +/- 12.3 units, significantly higher than in patients with RAS (10.0 +/- 5.5, p < 0.001), SLE (11.8 +/- 9.3, p < 0.03) or healthy volunteers (10.8 +/- 9.8, p < 0.02). Mean IgA-ASCA level was 16.8 +/- 8.8 units in the BD patients, significantly higher compared to healthy volunteers (11.0 +/- 5.0, p = 0.02) but similar to patients with RAS (17.0 +/- 5.3). No correlation was found between ASCA and any BD-associated clinical manifestation nor the presence of HLA-B5. No difference was found in the rate of major oral ulcers nor in the systemic disease severity score between positive- and negative-ASCA patients (27.3% vs. 30.8%, and 7.31 +/- 1.80 vs. 7.28 +/- 2.27 respectively, NS).

CONCLUSION

The results of our study associate, for the first time, the presence of a distinct antibody, i.e. ASCA, with BD. ASCA were not linked to a specific clinical manifestation of the disease and probably do not pose an increased risk for a more severe disease course.

In vitro antiviral and antibacterial activity of commercial intravenous immunoglobulin preparations--a potential role for adjuvant intravenous immunoglobulin therapy in infectious diseases

The identification of specific antimicrobial activity of intravenous immunoglobulin (IVIG) preparations against particular microbial pathogens can assist in determining their therapeutic potential for specific infectious diseases. We analysed five different commercial IVIG preparations for the presence of antibodies directed against a large panel of viral, bacterial, fungal and parasitic pathogens. All IVIG batches contained high activity against herpesviruses types 1, 2, 6 and 7, as well as against varicella zoster virus, Epstein-Barr virus (EBV), measles, mumps, rubella and parvovirus B19. Some IVIG batches also had a significant activity against adenovirus and Saint Louis encephalitis virus. The IVIGs held high activity against several bacterial pathogens, including Mycoplasma pneumonia, Chlamydia pneumonia, Helicobacter pylori and tetanus. No activity was found against various parasitic and fungal pathogens. Our findings may provide further support for the use of IVIG for the prevention and treatment of infections caused by specific viral and bacterial pathogens.

Prevalence of Behçet's disease in an Arab community in Israel

OBJECTIVE

To evaluate the prevalence of Behçet's disease (BD) in an Israeli Arab town (Taibe).

METHODS

Questionnaires about the occurrence and prevalence of aphthous ulcers were distributed randomly to the parents of children attending a paediatric centre in Taibe. The parents were asked whether they or any of their children aged between 10 and 20 years had recurrent aphthous stomatitis. Any who had had more than four aphthous episodes (each episode lasting more than seven days) during the previous year were invited for an extensive interview and examination by a rheumatologist or a paediatrician.

RESULTS

A total of 4876 subjects were included in this survey, of whom six (one male, five female) were diagnosed as having BD. Of these six, two were siblings (a brother and a sister). Five had skin lesions, four had visual involvement, and all had genital ulcers and joint symptoms; one in two patients had a positive pathergy test. Five of the six carried HLA-B5 antigens. The results showed a prevalence of 12/10,000 in Taibe.

CONCLUSION

The prevalence of BD found in our survey is high and concurs with that found in other Mediterranean and Asian countries.

Cytokine levels in various intravenous immunoglobulin (IVIg) preparations

The mechanisms of action of intravenous immunoglobulin (IVIg) in autoimmune diseases include modulation of cytokine levels. We examined therefore whether direct infusion of abnormally high levels of 13 different cytokines or cytokine-inhibitors within 5 different IVIg preparations have any role in modulation of their levels. None of the measured cytokines in any of the IVIg preparations tested were above the normal levels, and regarding some no traces could be detected. Hence, modulation of cytokine levels following IVIg therapy involves other mechanisms such as interference with their secretion or cytokine-specific blocking antibodies, rather than direct infusion of cytokines.

Allelic distribution of HLA-B*5 in HLA-B5-positive Israeli patients with Behçet's disease

In order to investigate the sub-typing of the B5 antigen in Israeli (Jewish and Arabic) patients with Behçet's disease (BD) allele-specific genotyping of B51 and B52 alleles was performed in Israeli BD patients and healthy controls. Among the HLA-B51-positive BD patients, B*5101 was found to be the predominant allele, identified in 62% of all BD patients and 78% of Jewish BD patients. HLA-B*5101 was also the predominant allele in HLA-B51-positive healthy controls. HLA-B*5108 and B*5104 alleles were identified in 23% and 15% of B51-positive BD patients, respectively. The HLA-B*5201 allele was identified in all HLA-B52-positive patients and controls. Our study suggests that both HLA-B*5101 and HLA-B*5201 are the dominant alleles of HLA-B5 in Israeli BD patients.

[Improved results in the treatment of acute myeloid leukemia - Results of study AML-BFM-93 in East Germany with comparisons to the preceding studies AML-I-82 and AML-II-87]

BACKGROUND

Three multicenter studies were conducted in East Germany on the treatment of acute myeloid leukaemia in children. The latest of the three studies (AML-BFM-93-OST) was part of the common German study AML-BFM-93.

PATIENTS AND METHODS

The total number of registered patients was 262. The number and dosage of administered chemotherapeutic agents was elevated with each new study.

RESULTS

Both the remission rate (85 %) and the likelihood of an event free survival (52 % after 5 years) could be improved significantly in study AML-BFM-93-OST. The results of the common German study AML-BFM-93 were identical to those of the East German part AML-BFM-93-OST. Compared with international studies it was one of the most successful treatment strategies in children with AML. Patients who showed toxic side effects to heart, liver, kidneys, skin or nervous system during the chemotherapy had a significantly lower risk of relapse, once they overcame the intensive therapy. During the five years of study AML-BFM-93-OST, treatment results could be improved despite an unchanged therapy strategy. This may partly be due to the modernisations and restorations that were carried out in many East German hospitals in this time.

CONCLUSIONS

The therapy regimen of study AML-BFM-93 allowed a substantial improvement in the treatment of children with AML. Further intensification of chemotherapy should only be undertaken in accordance to the individual sensitivity of each patient.

Inferior vena cava diameter: a useful method for estimation of fluid status in children on haemodialysis

BACKGROUND

An accurate assessment of fluid status in haemodialysis patients presents a significant challenge especially in growing children. Clinical parameters of hydration are not always reliable, and invasive methods such as measurement of central venous pressure cannot be used routinely. We evaluated the usefulness of inferior vena cava diameter (IVCD) measured by echocardiography in the estimation of hydration in children on haemodialysis.

METHODS

Fifteen haemodialysis patients (mean age 14 years) were evaluated. Clinical assessment included patients' symptoms, weight, blood pressure, heart rate, presence of oedema and vascular congestion, before and after dialysis session. Dry weight was assessed based on the above parameters. Fifty-two echocardiographic studies immediately prior and 30-60 min following dialysis were performed. The anteroposterior IVCD was measured 1.5 cm below the diaphragm in the hepatic segment in supine position during normal inspiration and expiration. IVCD was expressed per body surface area.

RESULTS

Following haemodialysis mean IVCD (average of expiration and inspiration) decreased from 1.12+/-0.38 to 0.75+/-0.26 cm/m(2) (P<0.0001). Changes in IVCD were significantly correlated with alterations in body weight following dialysis (P<0.0001). The collapse index (per cent of change in IVCD in expiration vs inspiration) increased significantly after dialysis (P=0.035). IVCD clearly reflected alterations in fluid status. It did not vary significantly with changes in dry weight in a given patient.

CONCLUSIONS

Our findings support the applicability of VCD measurement in the estimation of hydration status in paediatric haemodialysis patients. The combination of clinical parameters and measurement of IVCD may enable more accurate evaluation of hydration of children on haemodialysis.

Behçet's disease in Israel: the influence of ethnic origin on disease expression and severity

OBJECTIVE

To evaluate the relationship between ethnic origin and manifestations of Behçet's disease (BD) in Israel.

METHODS

We studied 100 Israeli patients with BD, 66 Jews and 34 Arabs. The 3 largest ethnic groups of Jewish patients originated from Iran/Iraq (n = 21), Turkey (n = 12), and North African countries (n = 21). Patients were evaluated with respect to the entire spectrum of disease manifestations, and a systemic severity score for BD was calculated for each patient. Disease expression was compared between Jewish and Arab patients and among Jewish ethnic groups.

RESULTS

There were no statistically significant differences between Jewish and Arab patients with respect to male:female ratio, prevalence of HLA-B5, age of disease onset, or disease duration. Disease expression and severity score were also similar in the 2 groups, but Arab patients had a higher rate of posterior uveitis (20.6 vs 4.6%; p < 0.03). Among the 3 largest Jewish ethnic groups, patients of North African origin had a significantly higher rate of ocular disease (p < 0.01), mainly in the form of anterior uveitis (p < 0.01). These patients also had higher rates of arthritis, overall vascular disease, deep vein thrombosis, and neuro-Behçet without reaching statistical significance. The disease severity score in this group was significantly higher compared to the other Jewish ethnic groups (p < 0.02).

CONCLUSION

The expression of BD is similar in Israeli Jewish and Arab patients but the latter have more severe eye disease. The disease in Israeli Jewish patients is most severe in those originating from North African countries.

Anti-endothelial cell antibodies (AECA) in systemic sclerosis--increased sensitivity using different endothelial cell substrates and association with other autoantibodies

OBJECTIVE

One of the main features of systemic sclerosis (SSc) is vascular damage, the mechanism of which is not understood. In the present study we examined whether screening of SSc patients for different anti-endothelial cells antibodies (AECA) of various origins increase the sensitivity of AECA detection in SSc patients. Secondary aim was an attempt to correlate AECA with other common autoantibodies.

MATERIALS & METHODS

478 SSc patients were studied for the presence AECA, anti-cardiolipin (aCL), anti-dsDNA, anti-heparin (AHA), anti-pyruvate dehydrogenase (PDH) and anti-PDC-E2 autoantibodies. AECA levels were detemined using human umbilical vein EC (HUVEC), bone marrow EC (BMEC), EC hybridoma (EA.hy 926) and Kaposi sarcoma EC (KS).

RESULTS

Positive AECA were found in 49.5% of SSc patients (27.1% HUVEC; 34.3% BMEC; 26.3% EaHy 926 and 22.7% KS). The highest percent reactivity of AECA was obtained using microvascular BMEC. When combining BMEC and either other cell lines the reactivity ranged from 41.4% to 46%. A significant association between AECA on the one hand and AHA (p<0.001)) and anti-PDH (p<0.05) on the other was secn. Cross-reactivity with anti-PDC-E2 was excluded by inhibition tests, but AHA and anti-PDH may be part of the spectrum of AECA.

CONCLUSIONS

Since false-negative AECA may result from lack of expression of various antigens on a specific EC, analysis of AECA in SSc patients requires using several EC types, including microvascular EC.

Improved method for the simultaneous determination of whey proteins, caseins and para-κ-casein in milk and dairy products by capillary electrophoresis

A capillary electrophoresis method for the simultaneous determination of whey proteins, caseins and their degradation products, such as para-kappa-casein, was proposed. The effect of several parameters (pH, ionic strength and concentration of urea in the electrophoresis buffer and applied voltage) on the analysis time and on the separation efficiency of the major milk proteins was studied. Using a hydrophilically coated capillary, in combination with electrophoresis buffer 0.48 M citric acid-13.6 mM citrate-4.8 M urea at pH 2.3, and a separation voltage of 25 kV, a complete separation of beta-lactoglobulin and para-kappa-casein was achieved, permitting the quantification of both components.

Immunomodulation of experimental autoimmune diseases via oral tolerance

The concept of oral tolerance refers to a form of peripheral tolerance in which mature lymphocytes in the peripheral lymphoid tissues are rendered nonfunctional or hyporesponsive by prior oral administration of an antigen. The primary mechanisms mediating oral tolerance include deletion, anergy of antigen-specific T cells and active cellular suppression, the primary determining factor being the dose of fed antigen. Low doses favor active suppression, whereas high doses favor deletion and anergy. Active cellular suppression is mediated by the induction of regulatory T cells in the gut-associated lymphoid tissue, which migrate to the systemic immune system. One of the primary mechanisms of active cellular suppression is via secretion of suppressive cytokines such as TGF-beta, IL-4, and IL-10 following antigen-specific triggering. TGF-beta is produced both by CD4+ and CD8+ GALT-derived T cells and is an important mediator of the active suppression component of oral tolerance. CD4+ cells that primarily produce TGF-beta appear to be a unique T-cell subset and termed Th3 cells. Oral tolerance was successfully studied in a variety of experimental models for autoimmune diseases, among them experimental autoimmune encephalomyelitis, experimental arthritis, experimental anti-phospholipid syndrome, experimental autoimmune uveoretinitis, experimental insulin dependent diabetes mellitus (IDDM), and experimental autoimmune myasthenia gravis. The results obtained in experimental animal models have led to the conduction of several clinical trials of oral tolerance in patients with multiple sclerosis, rheumatoid arthritis, uveitis, and IDDM. Conflicting results were obtained, and although some improvement has been noted in some of the patients, broad ranging clinical improvement has not yet been observed. A more accurate choice of antigens, as well as more precise dosing and timing of antigen-administration might lead to better results in the future.

Maxillomandibular brown tumor--a rare complication of chronic renal failure

We report a 17-year-old hemodialysis patient with a rapidly growing maxillary mass diagnosed as a brown tumor. Although successful control of the parathyroid hormone (PTH) levels was achieved by treatment with vitamin D pulse therapy, the lesion progressed, invaded the maxillary sinus, and caused severe eating and speech disabilities. No recurrence was observed following surgical excision. The differential diagnosis and considerations regarding the causes of the disease in a child, therapy options, and review of the literature are presented.

Peptide immunotherapy in autoimmune diseases

Peptide-mediated immunotherapy has been studied in a number of experimental models of autoimmune diseases and has also been tested in human patients to a certain extent. Copolymer 1 is a synthetic amino acid copolymer that has been demonstrated to suppress experimental autoimmune encephalomyelitis (a model for multiple sclerosis) when administered parenterally. Some study results indicate that mucosal tolerance induced by appropriate recombinant peptide fragments of human AChR is effective in suppressing experimental autoimmune myasthenia gravis and might be considered as a therapeutic modality for patients with MG. A peptide of the heat-shock protein 60 molecule, designated peptide p277, was shown to be a target of T cells in autoimmune diabetes in NOD mice, and intraperitoneal injections of glutamic acid decarboxylase (GAD) peptide 524-543 delayed the onset of diabetes and significantly reduced its incidence. Experimental evidence has revealed that CDR-based peptides may be potential candidates for the therapy of systemic lupus erythematosus. The use of synthetic peptides that focus on neutralization of pathogenic anti-beta 2GPI antibodies represents a possible new therapeutic approach to antiphospholipid syndrome. Studies in both acute and chronic-relapsing experimental autoimmune uveoretinitis have indicated that oral administration of S-Ag, S-Ag-derived peptides, inter-photoreceptor retinoid binding protein or HLA-derived peptides before immunization can protect animals from the disease.

SSCP analysis at the bovine CSN3 locus discriminates six alleles corresponding to known protein variants (A, B, C, E, F, G) and three new DNA polymorphisms (H, I, A1)

A high resolution SSCP protocol was developed for simultaneous discrimination of the known CSN3 alleles A, B, C, E, F and G. Furthermore, three new DNA polymorphisms were identified in different Bos taurus and Bos indicus breeds or crosses. Mendelian segregation was shown for two of these polymorphisms (named CSN3*H and 1), and the third (named CSN3*A1) was found in unrelated animals, thus indicating the presence of three additional alleles at the bovine CSN3 locus. DNA sequencing revealed single mutations that led to a Thr/Ile substitution in amino acid position 135 for CSN3*H and to a Ser/Ala substitution in position 104 of the deduced amino acid sequence of CSN3*1 (GenBank accession numbers AF105260 and AF121023) compared to CSN3*A. In CSN3*A1, a silent mutation in the third codon position of Pro150 was found (GenBank accession number AF092513).

Pathergy reaction in Behçet's disease: lack of correlation with mucocutaneous manifestations and systemic disease expression

OBJECTIVE

The pathergy reaction is a unique feature of Behçet's disease (BD) and, according to the International Study Group (ISG), is among the major criteria required for the diagnosis. Different positive pathergy reaction rates in BD have been reported worldwide. We evaluated the prevalence of the pathergy reaction in Israeli BD patients, and its relation to mucocutaneous and systemic manifestations of the disease.

METHODS

Forty-three patients were studied, all of whom fulfilled the ISG criteria for BD. The mucocutaneous and systemic disease manifestations were analyzed with respect to the presence of the pathergy reaction, and a systemic severity score for BD was calculated according to the potential morbidity and mortality associated with various clinical features.

RESULTS

Nineteen patients (44.2%) had a positive pathergy test. The pathergy-positive and pathergy-negative BD groups showed a similar male:female ratio, age at disease onset, and mean disease duration. They also exhibited similar HLA-B5 levels and a similar frequency of oral ulcerations in close family members. The mucocutaneous manifestations, systemic disease expression, and severity score were similar in patients with and without the pathergy reaction.

CONCLUSION

The presence of a positive pathergy reaction, although common in Israeli BD patients, is not associated with an increased risk for specific mucocutaneous or systemic manifestations of the disease, and probably does not predict a more severe disease course.

Low serum C3, leukopenia, and thrombocytopenia: unusual features of henoch-schonlein purpura

Henoch-Schonlein purpura (HSP) affects predominantly the skin, joints, gastrointestinal tract and kidney. Although the pathogenesis is probably of immune origin and complement activation is thought to play a role, laboratory findings including the serum level of the complement components are usually normal. We present a patient with a severe form of HSP nephritis who had unusual laboratory findings of a low level of C3, mild leukopenia and thrombocytopenia. These findings may further support the importance of complement activation in the pathogenesis of HSP.

Inhibition of diabetes in NOD mice by idiotypic induction of SLE

The present study was undertaken to investigate whether active induction of systemic lupus erythematosus (SLE) in non-obese diabetic (NOD) mice could affect their development of insulin-dependent diabetes mellitus (IDDM). NOD mice were immunized with a human IgM mAb carrying the 16/6 idiotype (MIV-7) or with control human IgM. The mice were bled monthly and tested for SLE-associated autoantibodies in the serum and for the presence of leukopenia, thrombocytopenia, proteinuria and immunoglobulin deposits in the kidneys. The development of diabetes was determined by a blood glucose level exceeding 15 mM on two consecutive weekly determinations and by the presence of insulitis in the pancreas. The NOD mice immunized with MIV-7 developed high and persistent levels of autoantibodies, including anti-DNA, anti-histones and anti-cardiolipin, untreated mice and those immunized with normal human IgM did not produce these autoantibodies. The MIV-7-immunized mice also manifested an elevated erythrocyte sedimentation rate, leukopenia, thrombocytopenia and significant proteinuria, as well as deposits of Ig in their kidney glomeruli. Thus, NOD mice immunized with MIV-7 developed both autoantibodies and clinical features of SLE. The MIV-7-treated mice, however, showed a significantly lower incidence of IDDM (25%vs. 90%, P<0.003), accompanied by amelioration of the insulitis. The present study indicates that the induction of SLE by idiotypic immunization can protect NOD mice from developing IDDM, pointing to the importance of immune dysregulation in shift from one autoimmune disease to another.

Anti-idiotype immunomodulation of experimental anti-phospholipid syndrome via effect on Th1/Th2 expression

Mice with experimental anti-phospholipid syndrome (APS), induced by active immunization with a human anti-cardiolipin MoAb (H-3), were treated with mouse anti-idiotypic MoAb (anti-H3, named S2.9) and with an irrelevant anti-idiotype. The immunized mice produced high titres of mouse anti-cardiolipin antibodies along with clinical manifestations of experimental APS: prolonged activated partial thromboplastin time (aPTT), thrombocytopenia and high rate of fetal loss. Treatment with the specific anti-Id (S2.9) as a whole molecule or F(ab)2 fraction, resulted in a decrease in serum levels of the anti-cardiolipin antibodies, rise in platelet count, shortened aPTT and reduced rate of fetal loss. The anti-Id effect was associated with a rise in the number of IL-2 and interferon-gamma (IFN-gamma)-secreting cells (Th1) and reduction in IL-4- and IL-6-secreting cells (Th2). The beneficial effect of the anti-Id treatment in mice with experimental APS induced by active immunization with an idiotype further supports the idiotypic aetiology of experimental APS and points to the role of Th1 cytokines in suppression of its manifestations.