Platelet activation and leucocyte-platelet aggregation in patients with venous stasis ulceration [VSU]

48 subjects were included in this study. They are classified into 3 groups: group 1-16 patients with venous stasis ulceration [VSU] of the leg due to chronic venous insufficiency [CVI] group II-16 patients with varicose veins of the leg without VSU and group III-16 normal healthy controls without evidence of venous diseases. Full detailed history and physical examination for all was done. The venous status for all patients was documented by means of duplex ultra-sonography and descending venography. Blood samples were drawn from the superficial veins of the leg just proximal to the ulcer from the patients with VSU, and from the superficial veins of the lower part of the leg from patients with V.V. without VSU [Local blood Samples]. Blood was also drawn from the antecubital vein from all [48] subjects [systemic blood Samples]. Whole-blood flowcytometry was used to analyse the samples before and after activation with a panel of agonists for evidence of platelet activation and the formation of leucocyte - platelet aggregation either monocyte - platelet aggregates or neutrophil - platelet aggregates patients with venous stasis ulceration [VSU] had a greater number of monocyte platelet aggregates in both the arm and leg samples than did the patients with V.V. without ulceration and than did the control subjects [P<0.01]. Furthermore, systemic blood samples from patients with venous stasis ulceration stimulated with either thrombin-receptor agonist peptide [TRAP], Adinosine diphosphate [ADP], or phorbol myristate acetate [PMA] formed more monocyte - platelet aggregates than did patients with varicose veins without ulceration and than did control sujbects samples [P<0.05]. No significant differences were found between the patients with V.V. without ulceration and control sujbects in platelet activation and leucocyte - platelet aggregation either before or after agonist stimulation. Also, there are no differences in platelet activation or neutrophil-platelet aggregate formation were noted among the three groups. Patients with VSU have an increase in the number of monocyte - platelet aggregates in systemic venous blood as well as in local venous blood [adjacent to venous stasis ulcer], implicating the monocyte as the leucocyte involved in the pathogenesis of VSU. No association was identified between the presence of a venous stasis ulcer and either neutrophil-platelet aggregation or the activation of individual platelets. Because platelet activation is necessary for the formation of monocyte-platelet aggregates, these data also suggest that monocyte-platelet aggregation is a more sensitive marker for in-vivo platelet activation than is the identification of individual activated platelets

Study of the role of C reactive protein measurement in reducing the rate of negative explorations for acute appendicitis

Appendicectomy for suspected acute appendicitis is a common procedure. The rate of normal appendices unnecessarily removed remains high [15-30%] despite several techniques and investigations used to improue our diagnostic accuracy. Many studies investigated the role of raised C-reactive protein in improving the diagnosis of acute appendicitis with con-jlicting results. This study emphasizes the impact of a normal [rather than raised] serum C-reactive protein in reducing the rate of negative explorations. In a double blind study, blood for the measurement of serum C-reactive protein [CRP] was collected pre-operatively from 156 patients just before going to the operating room for appendicectomy. The histopathology of the 156 appendices were grouped into positive [acute appendicitis] and negative [normal appendix]. White blood count [WBC], CRP and the histopathology findings were correlated. In patients with histopathologically proven acute appendicitis both the WBC count and serum CRP level were significantly raised [P=0.025 and P<0.0001 respectively]. Serum CRP level was normal in 26 out of 30 negative explorations [normal appendix on histopathology]. The specificity and sensitivity of serum CRP was 86.6% and 93.6% respectively. A normal preoperative serum CRP measurement in patients with suspected acute appendicitis is most likely associated with a normal appendix Deferring surgery in this group of patients would probably reduce the rate of unnecessary appendicectomies