Syphilis rarely attacks veins, but a gummatous inflammation has been observed in the portal vein and in the umbilical vein in new-born children. Leprosy may .attack the large veins of the extremity.

Tuberculosis affects veins in organs which are the seat of this process, and produces results similar to those in arteries. As the walls of veins are thin the process more readily penetrates to their calibre, and the tubercle bacillus may thus find entrance to the blood. Tuberculosis of veins is the most frequent cause of general tuberculosis, as already described.

Primary tumours of veins are excessively rare. A few cases of small Myomata have been described, and a larger tumour which was regarded as a myo-sarcoma (Perl). Tumours not infrequently penetrate into veins, on account of the thinness of their walls, but do not produce tumours in them.

Literature

Brodie, Lectures on Path, and Surgery, 1846; Nunn, Varicose veins and ulcers, 1852; Chapman, On varicose veins, 1856; Gay, Varicose, dis. of lower extrem., 1868; A. Cooper, On spermatocele, Guy's Hosp. Rep. vol. iii.; Virchow, Virch. Arch., iii.; Cohnheim, do., xxxvii.; Koster (Phlebectasis in intestine), Berl klin. Wochenschr., 1879; Lesser, Virch. Arch., ci.; Epstein, do., cviii.; Perl,. do., liii.