ABSTRACT
The first coherent pathophysiological scheme for sickle cell disease (SCD) emerged in the sixties-seventies based on an extremely detailed description of the molecular mechanism by which HbS in its deoxy-form polymerises and forms long fibres within the red blood cell that deform it and make it fragile. This scheme explains the haemolytic anaemia, and the mechanistic aspects of the vaso-occlusive crises (VOCs), but, even though it constitutes the basic mechanism of the disease, it does not account for the processes that actually trigger VOCs. This paper reviews recent data which imply: red blood cell dehydration, its abnormal adhesion properties to the endothelium, the participation of inflammatory phenomenon and of a global activation of all the cells present in the vessel, and finally, abnormalities of the vascular tone and of nitric oxide metabolism. These data altogether have shed a new light on the pathophysiology of the first molecular disease i.e. sickle cell disease.
Subject(s)
Anemia, Sickle Cell/blood , Anemia, Sickle Cell/metabolism , Cell Adhesion , Endothelium, Vascular/metabolism , Erythrocytes/metabolism , Erythrocytes/pathology , Hemoglobin, Sickle/genetics , Hemoglobin, Sickle/metabolism , Hemolysis , Humans , Ion Channels/metabolism , Nitric Oxide/metabolismABSTRACT
To search a possible difference in gout and in the risk factors for gout expression according to the hemoglobin in patients seen at the lome teaching hospital rheumatology clinic [Togo]. Medical records of patients seen during 17 years were studied. The patients affected by the gout and answering New York criteria have been included. All patients object of the comparison, benefitted from a hemoglobin electrophoresis and the search of possible risk factors for gout. Among the 14902 patients seen over a 17 year period, 214 had gout [210 males, 4 famales]. These 214 patients were carriers of an A A hemoglobin [147 cases], of an AS hemoglobin [41 cases], or of an AC [hemoglobin [26 cases]. The alcoholism, the obesity, and the arterial hypertension were the main risk factors associated with gout in 207 patients [97%]. Semiological and risk factors comparison according to the type of hemoglobin didn't show statistically significant difference. it results from this study that the AS hemoglobin and AC hemoglobin don't exercise any influence on the gout Semiological expression. Thus, the presence of one of these hemoglobins in gout patient must exercise no influence in the diagnostic gait and in the etiological investigation