Israel Medical Association Journal

Background: The effect of anti-platelet drugs on surgical blood loss and perioperative complications has not been studied in depth and the management of surgical patients taking anti-platelet medications is controversial.

Objective: To assess the effect of anti-platelet therapy on perioperative blood loss in patients undergoing appendectomy either laparoscopically or via open surgery.

Methods: We reviewed the files of all patients > 40 years old who underwent open or laparoscopic appendectomies from 2007 to 2010. Excluded were patients with short hospitalization and no follow-up of hemoglobin level, patients on warfarin treatment and patients who underwent additional procedures. Estimation of blood loss was based on decrease in hemoglobin level from admission to discharge. Risk factors for blood loss, such as anti-platelet therapy, age, gender, surgical approach, surgical time, surgical findings and complications, were analyzed.

Results: The final cohort included 179 patients (mean age 61 ± 14 years, range 40–93) of whom 65 were males. The mean perioperative hemoglobin decrease was 1.59 ± 1.07 mg/dl (range 0–5 mg/dl). Thirty-nine patients received anti-platelet therapy prior to surgery and 140 did not. No significant differences in decrease of hemoglobin level were found between patients receiving anti-platelet therapy and those who were not (1.73 ± 1.21 vs. 1.55 ± 1.02 mg/dl, P = 0.3). In addition, no difference was found between patients on anti-platelet therapy operated laparoscopically and those operated in an open fashion (1.59 ± 1.18 vs. 2.04 ± 1.28 mg/dl, P = 0.29). Five patients required blood transfusions, two of whom were on anti-platelet therapy. Blood loss was significantly greater in patients with a perforated appendicitis and in those with an operative time of more than one hour.

Conclusions: Anti-platelet therapy does not pose a risk for increased blood loss following emergent appendectomy performed either laparoscopically or in an open fashion.
 

Background: Several murine models are susceptible to atherosclerosis, such as low density-lipoprotein receptor-deficient (LDLR^-/-) and apolipoprotein E-deficient (apoE^-/-) mice, and are used for studying pathophysiological mechanisms. Atherosclerotic lesions in the aortic valve and thoracic/abdominal aorta are commonly associated with hyperlipidemia. We recently demonstrated the development of large atherosclerotic plaques in Helicobacter pylori-infected heterozygous LDLR^+/- apoE^+/- mice.

Objectives: To measure novel biomarkers related to atherosclerosis, blood coagulation, and oxidative stress in order to investigate their possible pathogenic roles in atherosclerosis-prone mice.

Methods: Mice were fed with a normal chow diet or high-fat diet and sacrificed at different age intervals to measure aortic plaque size. Plasma cholesterol was enzymatically measured. Enzyme-linked immunosorbent assay was used to measure oxidized LDL (oxLDL)/beta-2-glycoprotein I (β2GPI) complexes, immunoglobulin M (IgM) antibodies against native LDL, oxLDL, or oxLDL/β2GPI, and urine 11-dehydro-thromboxane B₂ (11-dhTxB₂) or 8-hydroxy-deoxyguanosine.

Results: There was a parallel increase in plaque size, plasma cholesterol, and urinary 11-dhTxB₂ in atherosclerosis-prone mice. In contrast to atherosclerosis-prone strains, an elevation of urinary 11-dhTxB₂ with no significant plaque generation was observed in LDLR^+/- apoE^+/- mice. The atherogenic autoantigen oxLDL/β2GPI complex was detected only in LDLR^-/- mice. These levels seem to depend on plaque size. IgM antibodies against oxLDL in apoE^-/- mice were found, accompanied by atherosclerotic progression.

Conclusions: Progression of atherosclerotic lesions was associated not only with cholesterolemia but also with platelet activation and natural autoimmune-mediated regulatory mechanism(s) in murine models.
 

Objectives: To describe patients with initially misdiagnosed PTP[1] and to emphasize the diagnostic pitfalls of this disorder.

Patients and Results: During a period of 11 years we have diagnosed six patients with PTP, four women and two men. The incidence of PTP was approximately 1:24,000 blood components transfused. We present the detailed clinical course of three of the six patients in whom the diagnosis was particularly challenging. The patients were initially misdiagnosed as having heparin-induced thrombocytopenia, systemic lupus erythematosus complicated by autoimmune thrombocytopenia, and disseminated intravascular coagulation. A history of recent blood transfusion raised the suspicion of PTP and the diagnosis was confirmed by appropriate laboratory workup.

Conclusions: PTP seems to be more frequent than previously described. The diagnosis should be considered in the evaluation of life threatening thrombocytopenia in both men and women with a recent history of blood transfusion.

Background: Platelet adhesion and aggregation are mediated by specific platelet membrane glycoproteins GPIa/IIa, GPIba, and GPIIb/IIIa, and are essential steps in thrombus formation and development of acute myocardial infarction.

Objective: To evaluate the risks exerted by each of the following polymorphisms: HPA-1a/b in GPIIIa; 807C/T in GPIa; and HPA-2a/b, VNTR and Kozak C/T in GPIba in young males with AMI[1]..

Methods: We conducted a case-control study of 100 young males with first AMI before the age of 53 and 119 healthy controls of similar age. All subjects were tested for the above polymorphisms.

Results: The allele frequencies of each of the platelet polymorphism were not significantly different between the young men with AMI and the controls. Smoking alone was associated with a 9.97-fold risk, and the presence of at least one metabolic risk factor resulted in a 2.57-fold risk of AMI.

Conclusion: These results indicate that platelet glycoproteins polymorphisms are not an independent risk factor for AMI.