Transfusion requirement during dengue fever epidemic in a rural medical college in south India.

Sir,

Dengue fever (DF) is the most rapidly spreading mosquito-borne viral disease in the world. In the last 50 years, the incidence has increased 30fold with increasing geographic expansion to new countries.[1] Dengue hemorrhagic fever (DHF) is a leading cause of serious illness and death in some Asian countries. These deaths can be prevented by timely diagnosis and transfusing platelets.

Karimnagar district of Andhra Pradesh faced an epidemic of DF from October to December 2009. The diagnosis of DF was done by clinical examination and confirmation by serology. This record based study was performed from January to March 2010. The permission of the Head of the institution and Institutional Ethics Committee was obtained. Analysis was done by percentage, Chi-square test, t-test and ANOVA.

Out of 500 cases, the majority were males, 315 (63%) and in the age group of 16–30 years. Transfusion support was given to 108 (21.6%) dengue cases of which 78 (72.22%) were males and 30 (27.78%) were females. Males required significantly higher transfusions than females (χ2 = 4.534, df = 1, P = 0.03322, OR = 1.7, CI = 1.066-2.713). Among those who received platelets, most patients i.e. 85 (78.70%) received a single unit of platelets. These patients responded well with one unit only, therefore, further platelet transfusion was not required. Chaudhary, et al[2] reported a rapid response to platelet transfusion in all cases. Makroo, et al[3] found 42.6% patients of DF receiving platelet transfusions.

The mean platelet count was 68714 cells/cumm. With repeated sampling of blood it was found that females showed a greater increase in platelet count as compared to males after platelet transfusion and the increase was statistically significant (P = 0.01665). After platelet transfusion, the mean platelet count improved from 68714 cells/cumm to 98753 cells/cumm. On applying the ANOVA test it was found that there was significant difference between various values of mean platelet count from first to seventh (F statistics =14.8251, P < 0.001)including males (F statistics =11.7423, P < 0.001) and females (F statistics = 5.74195, P < 0.001). It showed increasing platelet count from the first to the last sampling which was suggestive of clinical improvement. De Castro[4] found that mean platelet counts of less than 50,000/cumm in DHF patients increased to 91,500/cumm after therapy.

In conclusion, transfusion support was required in 20% of cases. Mean platelet count at the time of admission in all the subjects was found to be low and increased significantly after platelet transfusion. These patients were given symptomatic and supportive treatment. Thus, the platelet transfusion required was found to be low as those who required platelet transfusion, mostly required a single unit.