This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Drugs, Subject name: Medicine
Treatment of choice for tropical splenomegaly is : 
Select and explain. 
A. Chloroquine ' 6 months, B. Mefloquine ' 3 months, C. Proguanil, D. Pyrimethamine + sulphadoxine X 1 month
C: Proguanil
Answer: C: Proguanil 
Explanation: Ans. is 'c' Proguanil Tropical splenomegaly is a chronic complication of malaria. Some residents of malaria endemic areas in tropical Asia and Africa exhibit an abnormal immunological response to repeated infections with malaria.In these patients IgM antibodies develop against CD8 and CD5 cells. There is increase ratio of CD4/CD8 cells.These disturbances in immunological process results in splenomegaly. Anaemia and pancytopenia can also occur.