Abstract
Thromboangiitis obliterans (TAO) is a segmental inflammatory occlusive disorder that
affects small- and medium-sized arteries, and arm and leg veins of young smokers.
Several different diagnostic criteria have been offered for the diagnosis of TAO.
Clinically, it manifests as migratory thrombophlebitis or signs of arterial insufficiency
in the extremities. It is characterized by highly cellular and inflammatory occlusive
thrombi, primarily of the distal extremities. Thromboses are often occlusive and sometimes
display moderate, nonspecific inflammatory infiltrate, consisting mostly of polymor-
phonuclear leukocytes, mononuclear cells and rare multinuclear giant cells. The immune
system appears to play a critical role in the etiology of TAO. However, knowledge
about immunological aspects involved in the progression of vascular tissue inflammation,
and consequently, the evolution of this disease, is still limited. There are several
studies that suggest the involvement of genetic factors and results have shown increasing
levels of antiendothelial cell antibodies in patients with active disease. Vasodilation
is impaired in patients with TAO. TAO disorder may actually be an autoimmune disorder,
probably initiated by an unknown antigen in the vascular endothelium, possibly a component
of nicotine. There are various therapies available for treatment of TAO, but the major
and indispensable measure is smoking cessation. Except for discontinuation of tobacco
use, no forms of therapy are definitive. Sympathectomy, cil- ostazol and prostaglandin
analogues (prostacyclin or prostaglan- din E) have been used in specific conditions.
Recently, therapeutic angiogenesis with autologous transplantation of bone marrow
mono- nuclear cells has been studied in patients with critical limb ischemia.
