Thrombo-occlusive vasculitis mainly affects the middle and small arteries and veins of the extremities, with the lower extremity vessels being the main ones. It occurs in all parts of China, but is more common in the north. It occurs in young and middle-aged men and is rare in women. In 1908, Leo Buerger found that the lesions had an inflammatory reaction and thrombotic features, so it was named thrombo-occlusive vasculitis, also known as Buerger’s disease.
I. Etiology and pathology
The etiology of this disease is still not fully understood. Smoking, cold, humidity, malnutrition and sex hormone abnormalities have been considered as the main pathogenic factors of this disease, and smoking is particularly closely related to the pathogenesis. In the study of the pathogenesis, theories such as vascular neuromodulation dysfunction, blood hypercoagulability and adrenal hyperfunction have been proposed. In the last decade or so, immune factors have received attention. Through the observation of humoral immunity, cellular immunity and immunopathology of the disease, many scholars believe that the disease is an autoimmune disease.
The lesions mainly affect the small and medium-sized arteries, but the accompanying veins are also affected, but to a lesser extent. The arteries are narrowed and stiffened, and the entire vessel is non-suppurative and inflamed. The intima is thickened, with endothelial and fibroblastic proliferation and lymphocytic infiltration. The middle layer was fibrous tissue hyperplasia and the outer layer was extensive fibroblastic hyperplasia. The general structure of the vessel wall remains, and thrombus formation in the lumen occludes the vessel. Later thrombus mechanization allows recanalization of the lumen, but the recanalized tiny vessels cannot compensate for normal blood flow.
The lesions are often segmental, and there may be relatively normal vessels between the lesions. Later in the course of the disease, there is extensive fibrosis in and around the vessel wall, which surrounds the accompanying veins and nerves, forming a sclerotic strip. The pathologic changes in venous involvement are similar to those of arteries, except that there are more giant cells, leukocytes, and lymphocytes in the intimal layer and around the thrombus, more fibroblasts, leukocytes, and lymphocytes in the middle layer, and extensive fibroblast hyperplasia in the outer layer. In addition to the above pathological changes in blood vessels, there are also ischemic pathological changes in nerves, muscles, bones and other tissues.
Clinical manifestations
The disease starts insidiously and progresses slowly, often with periodic attacks, and often takes several years to become severe. The evolution of the disease process can be divided into three stages according to the degree of limb ischemia.
(a) Phase I (local ischemic phase) is the primary stage of the lesion. The main manifestations are numbness, coldness, fear of cold, soreness, easy fatigue, heaviness and mild intermittent claudication of the affected limb. The latter is the typical sign of this stage. When the patient walks 1 to 2 miles, the calf or foot muscles become distended or throbbing, and if he continues to walk, the pain worsens and he is finally forced to stop walking. After rest, the pain is immediately relieved. The symptoms reappear after walking again and are called intermittent claudication. As the condition progresses, the walking distance is gradually reduced. This is due to the increased oxygen demand of the muscles after walking. On examination, the skin temperature of the affected limb is reduced, the skin color is paler, and the dorsalis pedis artery or (and) the posterior tibial artery pulses are weakened. Wandering thrombophlebitis is often present.
(II) Phase II (dystrophic phase) The symptoms of numbness, coldness, coldness and soreness of the affected limb are aggravated, intermittent claudication is increasingly obvious, walking distance is shortened, rest time is prolonged, and pain turns to persistent. The pain does not stop even when the limb is at rest, which is called resting pain. It is more obvious at night. The skin temperature of the affected limb decreases significantly, the skin color becomes paler, or purple spots and flushing appear, the skin is dry, and the sweat hair is lost. Toe (finger) nail thickening and deformation, calf muscle atrophy, dorsalis pedis artery and posterior tibial artery pulsation disappear, N artery and femoral artery pulsation may also be weakened.
(C) Stage III (tissue necrosis stage) In addition to the above symptoms continue to worsen, the affected limb is severely ischemic, resting pain is more aggravated, the pain is intense and persistent, the patient sits with knees bent and feet clasped day and night, and stays awake at night. Patients are unable to sleep steadily at night. If local infection is complicated, fever, chills, irritability and other symptoms of systemic toxemia may appear. Ischemia of the extremity tissue is more severe, producing ulcers or gangrene. Most of the gangrene is dry, with the toe (finger) end dried and blackened, and may extend proximally. After the necrotic tissue is shed, a long-lasting ulcer is formed. If secondary infection develops, the gangrene is wet. Depending on the extent of gangrene, there are three levels.
Grade I, gangrene is limited to the toes (fingers);
Grade II, gangrene extends to the toe (metacarpal) joint and (metacarpal);
Grade III, gangrene extending to the heel, ankle or above the ankle joint.
The above staging is to identify the severity of the disease and the different stages of the disease process, so that the appropriate and effective treatment can be mastered. However, the staging is not static. If the lesion develops, the symptoms can be aggravated. If timely treatment can be given, the lateral branch circulation can be established, the local blood supply can be improved, the symptoms can be relieved, the disease can improve, and the stage and level can be changed.
III. Diagnosis
Thrombo-occlusive vasculitis has obvious clinical symptoms and signs, and the diagnosis is generally not difficult. The main points of diagnosis are.
①Most patients are young and strong men, especially with long-term heavy smoking habits;
(2) The dorsal or posterior tibial artery of the limb is weakened or absent;
③The limb has a history or clinical manifestation of wandering superficial thrombophlebitis;
④The initial onset is mostly unilateral lower limb, and later involves other limbs;
⑤ Generally no history of hypertension, hyperlipidemia, atherosclerosis or diabetes mellitus.
To assist in the diagnosis and to determine the site, extent and degree of arterial occlusion and the status of collateral circulation formation, the following tests are feasible in addition to the general examination.
(a) Limb elevation test (Buerger’s test) The patient lies flat, the affected limb is elevated by 45°, and after 3 minutes, observe the change in skin color of the foot; then have the patient sit up, with the lower limb hanging next to the bed, and observe the change in skin color. If the skin of the toes and sole is pale or waxy yellow after elevation, and the skin of the foot is flushed or appears patchy cyanosis after dropping, it is called a positive result.
(II) Auxiliary examination
① Skin temperature measurement checks the skin temperature of different parts of the limb, and the two limbs are compared with each other, which can show the degree and range of skin temperature reduction of the affected limb and help to understand the site of arterial occlusion and the degree of ischemia. If the skin temperature of the affected limb is 2° lower than that of the healthy side, it means that the blood supply is insufficient.
②Electrical impedance flowmetry is used to determine the impedance of the tissues to understand the status of blood supply and vascular elasticity by applying a hemogram lateralizer. The waveform of blood flow in the affected limb shows a decrease in the amplitude of the peak of the ascending branch and a decrease in the speed of the descending branch, and the degree of change is parallel to the degree of lesion in the affected limb.
③Doppler ultrasound angiography and blood flow measurement use Doppler ultrasound diagnostic instrument to directly probe the affected artery, which can show the morphology of the diseased artery, the diameter of the vessel and the flow rate of blood.
④Arteriography can clearly show the site, degree and extent of arterial lesions, as well as the collateral circulation. However, arteriography can cause vasospasm, aggravate limb ischemia and damage blood vessels, so it should not be used routinely and is usually considered before reconstructive surgery.
Differential diagnosis
Thrombo-occlusive vasculitis should be distinguished from the following diseases.
(a) occlusive arteriosclerosis thrombo-occlusive vasculitis and occlusive arteriosclerosis, both chronic occlusive vascular lesions, both quite similar in symptoms, signs and course development, but occlusive arteriosclerosis has the following characteristics.
① Patients are older, mostly over 50 years old, and do not necessarily have smoking habits;
②Often associated with hypertension, hyperlipidemia, coronary artery disease, atherosclerosis or diabetes mellitus;
③The diseased arteries are often large or medium-sized arteries, such as the bifurcation of the abdominal aorta, iliac artery, femoral artery or N artery, and rarely invade the upper limb arteries;
④X-ray may show irregular calcification shadows in the artery;
⑤ No manifestation of wandering superficial thrombophlebitis.
(B) Raynaud’s syndrome is an episodic spasm of the small arteries of the extremities caused by vascular nerve dysfunction, and its main clinical manifestation is that the skin color of the fingers (toes) suddenly turns pale, followed by purple, gradually turns flushed, and then returns to normal. A small number of patients with thrombo-occlusive vasculitis can also have the above-mentioned manifestations of Raynaud’s syndrome at an early stage, and therefore must be distinguished from it. The characteristics of Raynaud’s syndrome are as follows.
①Most of them are young women;
(2) The site of onset is mostly the fingers, and the onset is often symmetrical;
The arterial pulsation of the affected limb is normal, and gangrene rarely occurs at the end of the finger (toe) even if the disease has a long duration.
(c) Multiple aortitis Most often seen in young women; lesions often involve multiple large arteries; hypothermia and increased erythrocyte sedimentation rate are often present during the active phase; imaging shows narrowing or obstruction of the main branch openings of the aorta.
(d) periarteritis nodosa The disease mainly affects small and medium-sized arteries, and the limbs may show ischemic symptoms similar to those of thromboembolic vasculitis, which are characterized by: (1) extensive lesions, often involving arteries of the kidney, heart, liver, and gastrointestinal tract; (2) subcutaneous nodules, purple spots, ischemia or necrosis arranged along the arterial path; (3) fever, malaise, increased erythrocyte sedimentation rate, and hyperglobulinemia; (4) biopsy is often required to confirm the diagnosis. (v) diabetic necrosis
(E) Diabetic gangrene Thrombo-occlusive vasculitis requires differentiation from diabetic gangrene when gangrene of the extremity occurs. Patients with diabetes mellitus have a history of prolonged thirst, easy hunger, polyuria, positive urine sugar, and increased blood glucose.
V. Treatment
The principle of treatment for hemo-occlusive vasculitis is to promote collateral circulation, reconstruct blood flow, improve blood supply to the limb, reduce or eliminate pain, promote ulcer healing and prevent infection, and preserve the limb in order to restore labor force. The focus is on improving the blood circulation of the affected limb. At present, there are many methods to treat thrombo-occlusive vasculitis, all of which have certain efficacy. Some of the more commonly used treatment methods are introduced, which can be applied in a comprehensive manner according to the condition and clinical stage.
(A) Non-surgical therapy
A. General therapy Smoking is strictly prohibited to prevent cold, moisture and trauma. Keep the affected limb properly warm, but not hot compress or heat therapy, so as not to increase the tissue oxygen demand and aggravate tissue hypoxia and necrosis. Do not wear rigid shoes and socks to avoid affecting blood circulation in the foot. Make Buerger’s exercise for the affected limb to promote the establishment of lateral branch circulation. Method: The patient lies flat, elevate the affected limb 45-60°, maintain 2-3 minutes; then the patient sits up, both feet droop on the side of the bed, maintain 4-5 minutes; then lie flat, the affected limb flat on the bed, rest 4-5 minutes. This is done 3 times a day, 5 to 10 times per operation. For heavy pain, analgesics such as anti-inflammatory pain and somitol can be used. Morphine, markidine and other drugs are addictive and should be used with caution.
B. Drug therapy
1.Chinese medicine According to the combination of Chinese medicine and Western medicine, Chinese medicine is used to treat the disease.
①Yin-cold type Mostly belongs to the early stage or recovery stage. Treatment is based on warming the meridians and dispersing cold, with the help of invigorating blood circulation and removing blood stasis.
②Qi stagnation and blood stasis type Mostly in the second stage. The treatment is to dredge the meridians, invigorate the blood and remove blood stasis.
Damp-heat type is the third stage of mild toe-end gangrene and ulcers secondary to infection. The main treatment is to clear heat and dampness, together with activation of blood circulation and elimination of blood stasis, using Si Miao Yong An Tang with addition or Yin Chen Chi Xiao Dou Tang with addition.
Heat and toxicity type is the third stage of secondary infection and toxemia. The main purpose is to clear heat and detoxify the toxin, accompanied by cooling the Blood and resolving blood stasis.
⑤ Qi and Blood deficiency type Most commonly seen in recovery stage or in those with long-standing physical weakness. To nourish Qi and Blood, Gu Bu Tang can be added and subtracted.
In addition, through clinical application and pharmacological research, some herbs have been found to improve microcirculation, promote the formation of collateral circulation, and have anticoagulant, anti-inflammatory and analgesic effects. The following are commonly used clinically at present.
①Mao Dongqing Its active ingredient is flavonoid glycoside, which has peripheral vasodilating and anti-inflammatory effects. Take 200-300 grams daily as a punch or decoction. It can also be injected intramuscularly with Mao Dongqing injection, 2-4ml each time, 1 to 2 times daily.
②Compound Salvia injection 2~4ml each time, 1~2 times daily, intramuscular injection. 20ml can also be added to 500ml of 5% grape solution for intravenous injection, once a day, generally 2-4 weeks for a course of treatment. Clinical studies have confirmed that compound Salvia has the effect of accelerating the flow rate of red blood cells, improving peripheral microcirculation, reducing blood stasis and activating blood circulation, which can effectively improve clinical symptoms and promote ulcer healing.
③ Curcuma longa oil Add 50ml of 0.3% curcuma longa oil into 500ml of 5% glucose solution for intravenous infusion once a day, 14 times as a course of treatment, which also has good effect on improving symptoms.
2, vasodilators The application of vasodilator drugs can relieve vasospasm and promote collateral circulation. The commonly used vasodilators are.
①Tolazoline (Tolazoline, benzylzoline, priscoline) 25-50mg per time, orally, 3 times a day; or 2-50mg, intramuscular injection, 1~2 times a day.
②Papaverine 30～60mg, 3～4 times a day, orally or by subcutaneous injection. This drug has addictive properties and should not be used for a long time.
③Nicotinic acid 50～100mg, orally, 3 times a day.
④ magnesium sulfate 2.5% magnesium sulfate solution 100ml, intravenous drip, 1 to 2 times a day, 15 times for a course of treatment. After an interval of 2 weeks, the second course of treatment is feasible.
⑤ other such as phentolamine, benzylamine, benzpheniramine and butorphanolamine can be used.
3.Low molecular dextran can reduce blood consistency, increase the negative charge on the surface of red blood cells, and resist platelet aggregation, thus improving microcirculation, preventing thrombus extension, and promoting the formation of collateral circulation. 500ml each time, 1~2 times a day, intravenous drip, 10~14 days for a course of treatment. It can be repeated at intervals of 7 to 10 days. It should not be used when the ulcer gangrene is secondary to infection, so as not to cause the spread of inflammation.
4.Defibrinization treatment The application of an anticoagulant substance extracted from snake venom can reduce fibrinogen and blood viscosity, which can be used to treat arteriovenous thrombosis with good results. In recent years, China has purified “antithrombin” and “clear thrombin” from northeast snake island and Changbai Mountain pit viper venom, which can be used to treat thrombo-occlusive vasculitis, with good effect and no obvious side effects.
5.Prostaglandin E1 (PGE1) has the function of vasodilatation, anti-platelet and prevention of atherosclerosis, which has been used for the treatment of thrombo-occlusive vasculitis only in recent years.
C. Physical therapy
1.Ultrasonic wave Use ZY-1 ultrasonic wave instrument, using direct and indirect contact method, to treat the affected limb. Once a day, 30-60 minutes each time, rest 1 day after 6 times, 24 times for 1 course of treatment.
2, negative limb pressure and positive and negative pressure alternate therapy Under negative limb pressure, the affected limb blood vessels can be passively dilated, which has the effect of improving blood flow and increasing the formation of collateral circulation. During treatment, the affected limb is placed in a closed chamber, and the upper limb is given -10.6KPa (-80mmHg) and the lower limb is given -13.3KPa (-100mmHg) pressure for 10-15 minutes each time, once or twice a day, 10-20 times for a course of treatment. The combination of positive and negative pressures can promote blood return under positive pressure and blood entry into the limb under negative pressure, thus increasing blood flow to the limb and improving blood circulation. Generally, it is -6.7～+13.3KPa (-50～+100mmHg) alternating with each other, each holding 10～15 seconds, treatment time 30～60 minutes, 1～2 times a day, 10～20 times a course of treatment.
3. Hyperbaric oxygen In the hyperbaric oxygen chamber, the oxygen supply to the limb can be increased through the increase of blood oxygen, which is effective in reducing pain and promoting wound healing. Once a day, 3-4 hours each time, 10 times as a course of treatment.
(II) Surgical treatment
1.Lumbar sympathetic ganglion resection
2.Arterial thrombus endarterectomy
3.Arterial bypass grafting
4.Large omental transplantation
5.Arterialization of limb veins
6, Amputation
Prevention
(1) Absolute abstinence from smoking Statistical studies show that the incidence of occlusive thrombophlebitis in patients who smoke is much higher than the prevalence of non-smokers. Smoking can cause peripheral vasoconstriction, or even spasm, increasing the degree of lumen occlusion, thus aggravating the disease.
(2) Keep the feet clean and dry to prevent trauma and infection Patients with vasculitis are prone to infection due to insufficient blood supply to the legs and reduced skin resistance. Clean, dry feet are less likely to be attacked by bacteria. And once the foot is traumatized, the wound will not heal, combined with infection.
(3) local insulation Some people believe that vasculitis is related to the cold. Cold can make the vascular contraction or even spasm, so that the occlusion of the blood vessels more poorly, aggravating the disease. But insulation should not be overheated, so as not to enhance local metabolism, increase oxygen consumption, aggravate the local ischemic performance.
(4) Change position at any time during labor Do not maintain the same posture for a long time, so as not to affect blood circulation, especially long-term standing, blood stagnation in the lower extremities, will aggravate local swelling and pain and other symptoms.
(5) Avoid the use of vasoconstrictive drugs epinephrine, ephedrine and other drugs have the effect of vasoconstriction, the use of such drugs will cause peripheral vasoconstriction, narrowing of the lumen, increased venous pressure, thereby aggravating the condition.