DHF characterized by acute type DIC with increased vascular permeability

Decreases in platelet count, fibrinogen concentration, factor VIII, antithrombin III and alpha 2-antiplasmin activities, increase in FDP-D fraction, and pleural effusion were observed transiently at early fever stage of DHF at grade II, indicating DHF patients had manifestations of the acute type of DIC with increased permeability of vascular wall.

Protection against marked plasma leakage in dengue haemorrhagic fever by infusion of carbazochrome sodium sulfonate (AC-17)

Patients diagnosed clinically as having grade II dengue haemorrhagic fever, and confirmed serologically to have been recently infected by dengue virus were randomly assigned to two groups, to assess suppression of plasma leakage by intravenous administration of carbazochrome sodium sulfonate(AC-17). The double-blind prospective study over three successive epidemic periods included 39 patients in the placebo group, and 38 in the AC-17 group. The effects of the administration were evaluated with respect to pleural effusion of the chest X-ray films. A clear difference between the two groups was found in the numbers of patients with pleural effusion and severity of the pleural effusion thus the administration of AC-17 may be useful in eliminating the risk factors of severe bleeding and shock in dengue haemorrhagic fever.

Enhancement of collagen-induced aggregation of platelets in whole blood

In order to elucidate the features of platelet aggregation in whole blood, studies were carried out on human blood. The platelet aggregation reaction was monitored by counting the residual free platelet number with an electronic particle counter (Coulter). Platelets in citrated whole blood were aggregated by a very small amount of collagen which did not aggregate platelets in citrated plasma. Such enhancement was not observed if ADP or epinephrine was used. By addition of isolated erythrocytes to platelet rich plasma, enhancement of the platelet response to collagen was obtained. The erythrocyte membrane stabilizer, Dilazep, abolished the enhancement effect of erythrocytes. Those results indicated that erythrocytes enhanced the platelet response to collagen. Although participation of ADP from the erythrocytes in the enhancement was suggested, the results of ADP determinations on suspensions of erythrocytes indicated that other factors of the erythrocytes might be involved in the enhancement.