Commonest cause of rupture of spleen is
spontaneous splenic rupture, which remain widely accepted to date: Mechanical effect of distention secondary to leukemic infiltration of the spleen, paicularly the capsule; splenic infarct with capsular hemorrhage and subsequent rupture; Ref Davidson edition23rd pg812
Chronic malaria
Infectious mononucleosis
Leukemia
Chronic kala azar
G.I.T