Israel Medical Association Journal

Background: Approximately 80% of patients with myelodysplastic syndromes (MDS) receive multiple red blood cells (RBC), often multiple transfusions, and are therefore prone to develop alloantibodies against RBC. Because of increasing evidence for the role of immune dysregulation in the pathobiology of MDS, we hypothesized that in patients with MDS there is an increase in alloantibody formation beyond that expected by multiple transfusions.

Objectives: To determine the prevalence rates of alloantibodies in patients with MDS who are transfusion dependent and compare them to those of non-MDS patients matched for number of RBC units they received. 

Methods: The blood bank database was screened to identify non-MDS patients matched for age and number of units transfused. Logistic regression analysis was applied to determine factors affecting alloantibody formation. 

Results: Of 60 patients with MDS, 18 (30%) developed alloantibodies against RBC. Transfusion-dependent MDS and non-MDS patients (N=56 each), matched for number of RBC units and age, were compared. Fifteen MDS patients (27%) but only 12 non-MDS patients (12%) developed alloantibodies (P = 0.057). The relative risk for developing antibodies in MDS patients was 2.14, and MDS was the strongest predictor for formation of alloantibodies during transfusion therapy (odds ratio 3.66, confidence interval 1.4–9.3). 

Conclusions: Patients with MDS are at increased risk to develop RBC alloantibodies, partly because these patients receive multiple RBC transfusions. Whether matching for RH and KEL would lead to lower rates of RBC alloantibodies remains to be determined.

 

Background: The association between antiphospholipid antibodies (aPL) and multiple sclerosis (MS) has been suggested previously, but prior studies provided contradicting findings. 

Objectives: To characterize the expression profile of eight classic and non-classic aPL in patients diagnosed with MS.

Methods: Using the BioPlex™ 2200 immunoassay, we measured the levels of serum immunoglobulin (Ig)M and IgG isotypes of three classic aPL and five non-classic aPL in 98 subjects with MS and 237 healthy controls. 

Results: Three non-classic aPL were significantly more prevalent among MS patients in comparison to the control group. These antibodies included IgM and IgG against phosphatidylserine-β2GPI (PS-B2), IgG prothrombin complex (PT-PT) and IgM prothrombin (PT). The positive results according to Bonferroni correction are PS-B2 IgG and PT-PT IgG. The remaining aPL profiles did not differ significantly between the two groups.

Conclusions: An association between certain non-classic aPL and MS has been established. The specific role of these autoantibodies in the pathogenesis of the condition remains uncertain.  

 

A fundamental challenge for multiple sclerosis (MS) therapy is to promote repair and remyelination beyond their limited spontaneous extent. Glatiramer acetate (GA, Copaxone®), an approved treatment for MS, has been shown to induce immunomodulation as well as neuroprotection in the inflamed central nervous system (CNS) in MS and in its model, experimental autoimmune encephalomyelitis (EAE). Using electron microscopy, immunohistochemistry, and advanced magnetic resonance imaging, we have demonstrated diminished myelin damage in GA-treated mice, in both relapsing-remitting and chronic EAE, even when treatment was applied late after the disease exacerbation, suggesting repair. Furthermore, quantitative analysis indicated significant elevation in remyelinated axons in GA-treated compared to untreated EAE mice. To further prove that GA can promote myelination, we studied its effect in the developing naïve CNS, when injected postnatally. Immunohistochemical and ultrastructural analyses revealed significant increase in the number of myelinated axons, the thickness of the myelin encircling them, and the resulting g-ratios in the spinal cords of GA-injected mice compared to their phosphate-buffered saline-injected littermates. A prominent elevation in the amount of progenitor oligodendrocytes and their proliferation, as well as in mature oligodendrocytes, implied that the effect of GA is linked to the differentiation along the oligodendroglial cascade. Furthermore, a functional advantage in rotating rod test was exhibited by GA-injected mice over their littermates. These cumulative findings indicate that GA treatment affects myelination under inflammatory as well as non-inflammatory conditions, supporting the notion that the repair process in the CNS can be up-regulated by therapy.

Objective: To assess the impact of multiple births on the severity of RSV infection and define risk factors for acquiring RSV infection in infants of multiple birth.

Methods: Clinical data on infants hospitalized with RSV infection between 2008 and 2010 were retrospectively collected.

Results: Twins comprised 7.6% (66/875) of hospitalized infants with RSV bronchiolitis during the study period. Infants in the twin group were younger (122.4 ± 131.7 vs. 204.5 ± 278.8 days, P = 0.014), had a lower mean gestational age (35.3 ± 2.6 vs. 38.6 ± 2.5 weeks, P < 0.001), and were more likely to have been born prematurely compared with singleton infants (65.6% vs. 13%, P < 0.001). On a multivariable logistic regression analysis, young age, early gestational age and male gender were the only variables identified as risk factors for pediatric intensive care unit admission (P < 0.001, P < 0.001 and P = 0.03, respectively). In contrast, the mere fact of a child being a twin was not found to be a significant risk factor for disease severity. In addition, if one twin is hospitalized due to RSV infection, the other has a 34% chance of also being hospitalized with bronchiolitis. Young age was a significant risk factor for hospitalization of the second twin (P < 0.001).

Conclusions: Our findings suggest that twins hospitalized with RSV bronchiolitis do not have an increased risk for severe infection as compared to singletons. However, a twin of an infant hospitalized with RSV infection has a considerable risk of also being hospitalized with bronchiolitis, thus close monitoring is recommended.