Israel Medical Association Journal

Background: Syncope is a common clinical problem that often remains undiagnosed despite extensive and expensive diagnostic evaluation.

Objectives: To assess the diagnostic evaluation, costs and prognosis of patients hospitalized for syncope in a tertiary referral center according to discharge diagnosis.

Methods: We retrospectively reviewed the medical records of patients with a diagnosis of syncope discharged from a tertiary referral center in 1999. In addition, mortality data were obtained retrospectively a year after discharge for each patient.

Results: The study group comprised 376 patients. Discharge etiologies were as follows: vasovagal 26.6%, cardiac 17.3%, neurological 4.3%, metabolic 0.5%, unexplained 47.3%, and other 4%. A total of 345 patients were admitted to the internal medicine department, 28 to the intensive cardiac care unit, and 3 to the neurology department. Cardiac and neurological tests were performed more often than other tests, with a higher yield in patients with cardiac and neurological etiologies respectively. The mean evaluation cost was 11,210 ± 8133 shekels, and was higher in the ICCU[1] than in internal medicine wards (19,210 ± 11,855 vs. 10,443 ± 7314 shekels, respectively; P = 0.0015). Mean in-hospital stay was 4.9 ± 4.2 days, which was longer in the ICCU than in medicine wards (7.2 ± 5.6 vs. 4.6 ± 3.5 days, respectively; P = 0.024). Short-term mortality rates (30 days after discharge) and long-term mortality rates (1 year after discharge) were 1.9% and 8.8% respectively, and differed according to discharge etiology. LTM[2] rates were significantly higher in patients discharged with cardiac, neurological and unknown etiologies (not for vasovagal), compared with the general population of Israel (1 year mortality rate for the age-adjusted [65 years] general population = 2.2%). The LTM rate was higher in patients discharged with a cardiac etiology than in those with a non-cardiac etiology (15.4% vs. 7.4%, P = 0.04). Higher short and long-term mortality rates were associated with higher evaluation costs.

Conclusions: Hospitalization in a tertiary referral center for syncope is associated with increased mortality for most etiologies (except vasovagal), cardiac more than non-cardiac. Despite high costs of inpatient evaluation, associated with more diagnostic tests, longer in-hospital stay and higher mortality rates, nearly half of the patients were discharged undiagnosed. Outpatient evaluation should be considered when medically possible.

Background: Standard CD44 and its alternatively spliced variants were found to be associated with the metastatic potential of tumor cells and with cell migration of autoimmune inflammatory cells, including cells involved in experimental insulin-dependent diabetes mellitus.

Objectives: To investigate whether induction of anti-CD44 immune reactivity, through cDNA vaccination, could attenuate IDDM[1] in a transfer model of NOD mice.

Methods: Our vaccination technique involved the insertion of CD44s[2] or CD44v[3] cDNA into a silicone tube filled with a 2.5 cm long segment of hydroxylated-polyvinyl acetate wound dressing sponge (forming a virtual lymph node) which was implanted under the skin of male NOD recipients reconstituted with diabetogenic spleen cells of female NOD donors. The VLN[4] were implanted 20 days before and 3 days after cell transfer.

Results: In contrast to control groups of recipient mice, recipients vaccinated with VLN loaded with CD44v or CD44s cDNAs developed resistance to IDDM almost to the same extent. Our results suggest that the gene vaccination effect was mediated by anti-CD44 antibody rather than by cellular immunity. Histopathological examinations revealed a significant protection of pancreatic islets in the DNA-vaccinated recipients, whereas the islets of control recipients of diabetogenic cells were almost totally destroyed.

Conclusions: These findings may open new opportunities for IDDM therapy in the future.

High mobility group box 1 is a nuclear protein participating in chromatin architecture and transcriptional regulation. When released from cells, HMGB1[1] can also act as a pro-inflammatory mediator or alarmin. Upon stimulation with lipopolysaccharides or tumor necrosis factor-alpha, HMGB1 is secreted from certain cells such as monocytes/macrophages and fosters inflammatory responses. In addition, HMGB1 is passively released from necrotic cells and mediates inflammation and immune activation. In contrast, during apoptotic cell death, nuclear HMGB1 gets tightly attached to hypo-acetylated chromatin and is not released into the extracellular milieu, thereby preventing an inflammatory response. There is accumulating evidence that extracellular HMGB1 contributes to the pathogenesis of many inflammatory diseases, including autoimmune diseases. Increased concentrations of HMGB1 have been detected in the synovial fluid of patients with rheumatoid arthritis. In animal models of RA[2], HMGB1 appears to be crucially involved in the pathogenesis of arthritis, since neutralization of HMGB1 significantly ameliorates the disease. Also, in the serum and plasma of patients with systemic lupus erythematosus we detected substantial amounts of HMGB1, which may contribute to the disease process. However, investigations of blood concentrations of HMGB1 and its relevance in human diseases are hindered by the lack of reliable routine test systems.

Medical screening is not a tangible existent tool in autoimmune disorders as it is in other illnesses. Numerous attempts are made to identify individuals destined to develop an autoimmune disease, including analysis of the genetic background, which along with the immunological profile, may assist in identifying those individuals. If these efforts turn out to be successful they may lead to the possibility of proactive measures that might prevent the emergence of such disorders. This review will summarize the attempts made to pursue autoantibodies specific for the central nervous system as potential predictors of autoimmune neurological disorders.

Background: The presence of anti-cyclic citrullinated peptide autoantibody is highly specific for rheumatoid arthritis. Certain HLA-DR4 (HLA-DRB1*04) alleles, also known as the "shared epitope," are associated with increased susceptibility to RA[1]. In addition, these alleles may also have relevance for disease outcome. Anti-CCP[2] antibody positivity has been associated with the presence of HLA-DR4 alleles in patients with RA. However, there is little information available regarding any relationship between quantitative anti-CCP production (serum anti-CCP concentrations) and the shared epitope.

Objectives: To determine the association between anti-CCP antibody production and various HLA-DRB1 alleles.

Methods: Serum anti-CCP, rheumatoid factor and C-reactive protein levels were assessed in 53 RA patients. All these patients underwent HLA-DRB1 genotyping.

Results: Of the 53 patients 33 (62%) were positive for anti-CCP antibody. We found significant correlations between anti-CCP and RF[3] positivity (chi-square = 6.717, P < 0.01), as well as between anti-CCP and HLA-DRB1*04 positivity (chi-square = 5.828, P < 0.01). There was no correlation between RF positivity and serum levels, CRP[4] serum levels and HLA-DRB1*04 positivity. When quantitatively comparing serum anti-CCP levels with shared epitope positivity, patients carrying one or two copies of HLA-DRB1*04 alleles had significantly higher anti-CCP concentrations (530.0 ± 182.6 U/ml) compared to DRB1*04-negative patients (56.8 ± 27.4 U/ml) (P < 0.01). There was no difference in serum anti-CCP antibody concentrations between patients carrying only one HLA-DRB1*01 allele but no HLA-DRB1*04 allele (12.0 ± 8.6 U/ml) in comparison to SE[5]-negative patients (76.8 ± 56.2 U/ml). Regarding non-SE HLA-DRB1 genotypes, all 6 patients (100%) carrying DRB1*15 alleles and 6 of 7 (85%) patients carrying DRB1*13 were anti-CCP positive. In addition, patients with HLA-DRB1*13 (282.5 ± 23.8 U/ml) and DRB1*15 (398.7 ± 76.2 U/ml) produced significantly more anti-CCP than did any other non-SE HLA-DRB1 subtypes (P < 0.01).

Conclusions: There is significant association between anti-CCP and RF, as well as between anti-CCP and SE positivity in RA. In addition, the presence of one or two copies of HLA-DRB1*04 alleles has been associated with higher serum anti-CCP antibody levels. Thus, patients carrying HLA-DRB1*04 alleles exhibited an overall tenfold increase in serum anti-CCP antibody levels in comparison to HLA-DRB1*04-negative subjects. Increased anti-CCP production may also be associated with other non-SE HLA-DRB1 genotypes, such as DRB1*13 or DRB1*15. In reports by other investigators, both anti-CCP concentrations

Idiotypic analyses of anti-DNA autoantibodies were widely reported a decade ago. More than 100 studies were conducted on one of the main analyzed idiotypes, the 16/6 Id of the anti-ssDNA monoclonal antibody. In this review we summarize current knowledge on the characteristics of the 16/6 Id[1], its link to infection and its target epitopes on other molecules known so far. This includes the modulation of T and B cell responses and gene expression by the 16/6 mAb[2] in vitro and in vivo. We focus on the ability and mechanisms by which this idiotype induces experimental lupus in naïve mice, manifested by autoantibody spread, kidney and brain involvement, and leukopenia associated with enhanced sedimentation rate. We also discuss various therapeutic modalities to treat 16/6 induced lupus in mice.

The antiphospholipid syndrome is characterized by recurrent fetal loss, venous and/or arterial thrombosis, and thrombocytopenia associated with elevated titers of lupus anticoagulant and anticardiolipin antibodies. Although thrombosis is the characteristic vascular involvement in APS[1], the development of vascular aneurysms in patients with APS has been reported. We describe four patients with established APS, who developed abdominal aortic aneurysm, and review the literature on previous published cases of arterial aneurysms developing in patients with APS. In addition, we discuss the possible pathophysiological association between APS and the development of this vascular abnormality.