To the Editor.–Your editorial, "Hemorrhoids," in the June Archives (108:762, 1974) intrigues me on two counts.
Thulesius and Gjöres admit, as you say, "that the traditional cause of hemorrhoids, increased local pressure, is as important as ever." In view of two means of venous drainage of the hemorrhoidal plexus, the caval venous system and the portal system, pressure, in my opinion, is seldom a principal cause of hemorrhoids. A notable exception to this is the presence of a pelvic (and abdominal) tumor that may exert pressure on hemorrhoidal tributaries to both the caval and the portal systems, as in pregnancy in its third trimester. However, hemorrhoids occur also in women who have never been pregnant and in men. It seems logical, therefore, to assume the presence of a principal factor in the pathogenesis of hemorrhoidal disease that is common to both sexes. This factor is anal infection, involving anal