Peripheral Vascular Disease

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[edit] Peripheral Vascular Disease

Jay D. Coffman

[edit] OBSTRUCTIVE ARTERIAL DISEASE

[edit] Epidemiology and Etiology

Patients with obstructive arterial disease complain of pain, tightness of muscles, fatigue, or weakness of the legs on walking. Symptoms are relieved by rest within a few minutes. This symptom is termed intermittent claudication, which means to limp intermittently.^[1] Most patients have arteriosclerotic obstructive arterial disease. About 2.1% of males and 1.6% of females have symptoms suggesting intermittent claudication. The prevalence is markedly increased in diabetic patients. The incidence is two times greater in smokers than in nonsmokers and increases with the intensity of the habit. The ratio of men to women is about 3:1. Females lag behind males by about 10 years in development of the disease.

[edit] Pathophysiology

The symptoms are usually caused by obstructive arterial disease due to arteriosclerosis. The obstructed or stenosed large or medium-sized artery limits blood flow to the active muscle. A decreased perfusion pressure distal to the lesion falls further with the vasodilation of exercise, and the muscle contraction may actually stop blood flow. Diabetic patients may have more severe and progressive arteriosclerosis obliterans than others. Other risk factors for arteriosclerotic occlusive disease are tobacco smoking, hypertension, and hyperlipoproteinemias.

[edit] History

The patient's muscle symptoms occur after walking a remarkably constant distance, except they are aggravated by walking on inclines or when heavy bundles are carried. The location of the discomfort sometimes helps define the vessel affected; however, calf claudication may occur with the disease at any vascular level, since these muscles are most involved in walking. Low back or buttock claudication suggests aortoiliac disease, thigh pain indicates iliac or common femoral artery disease, and foot symptoms point to diseased vessels at or below the popliteal artery. The most common lesion is an obstruction or stenosis of the superficial femoral artery in the adductor canal, and it causes calf claudication. The other symptoms of obstructive arterial disease of the limbs are rest pain, numbness, and paresthesia. When these occur, the circulation is severely compromised, since even the small nutritional requirements of the skin are not being met. These symptoms usually occur only in feet; rest symptoms in muscles are rare.

[edit] Physical Examination

Most patients with only intermittent claudication have normal appearing limbs. There may be global atrophy of the lower limbs in patients with aortoiliac disease. Hair may be sparse on the lower limbs and absent on the toes. Observation of the limbs in the dependent position may reveal dependent rubor, which is a purplish red discoloration of cool feet seen in patients with rest symptoms. Ulcers and small areas of gangrene may be present, usually on the toes.

All pulses are palpated, and auscultation for bruits over the femoral arteries and abdominal aorta is performed. A systolic bruit indicates an arterial lesion proximal to the point of auscultation, and if accompanied by a decreased pulse, it is a hemodynamically significant obstruction. A diastolic component to the bruit indicates poor collateral blood flow.

The collateral circulation to the affected limbs can be evaluated by a simple office test. With the patient supine, elevation of the limbs at a 45-degree angle should not produce pallor. If the feet become pale, the collateral circulation is not fully compensatory. The patient is then asked to assume a sitting position with the limbs dependent. The feet should flush immediately and the veins of the dorsal foot fill within 20 seconds. If the flushing and venous filling times exceed 30 seconds, the collateral circulation is borderline.

[edit] Laboratory Studies and Diagnostic Procedures

In the few patients in whom the diagnosis cannot be made by physical examination, the most valuable test is the measurement of ankle systolic blood pressure via Doppler methods. This pressure should be equal to or greater than the arm pressure. Arteriography or magnetic resonance arteriography defines the anatomy of the diseased vascular tree but yields little hemodynamic information. It is useful only if surgery is being considered and is rarely needed as a diagnostic test.

[edit] Differential Diagnosis

In over 90% of patients arteriosclerosis obliterans is the cause of intermittent claudication. There are other vascular and nonvascular etiologies (Table 70-1). Neurogenic claudication may be secondary to a prolapsed intervertebral disk, stenosis of the canal, or hypertrophic bony ridging in the intervertebral canal.

Table 70-1 Differential Diagnosis of Leg Pain with Exercise

Thromboangiitis obliterans (Buerger's disease) is a rare cause of intermittent claudication.^[2] The etiology is unknown. Small and medium-sized arteries and veins are affected by an inflammatory reaction; thrombosis in blood vessels may contain sterile microabscesses and multinucleated cells. There are characteristic areas of normal blood vessel between involved segments. The typical patient is a man 20 to 40 years of age, and almost all patients are smokers. Patients usually present with ischemic symptoms or signs in the feet or intermittent claudication. Vasospasm and migratory superficial thrombophlebitis may occur in up to 40% of patients.

[edit] Clinical Course

Several studies have shown that 60% to 90% of patients with intermittent claudication due to arteriosclerosis remain stable or improve over a 5-to 9-year period. Patients with diabetes mellitus usually have progressive disease; their amputation rate is four times greater than that in patients with obstructive arterial disease without diabetes. Acute ischemic events occur in 25% of patients over 4 to 7 years. The amputation rate is about 0.8% to 1% per year but is much higher in diabetics and smokers. Obstructive arterial disease is a marker for shortened survival. Most of these patients die a decade earlier of coronary artery disease and/or diabetes.

[edit] Management

Most patients with intermittent claudication should be treated conservatively. The immediate success rate of graft bypass surgery of the superficial femoral artery is 80% to 90%, and the 5-year graft patency rate is 70% in the best vascular centers. Balloon angioplasty of the iliac arteries can produce excellent results but not in more distal vessels. In Maryland it was found that the use of balloon angioplasty increased 24-fold and peripheral bypass surgery doubled, but the rate of lower extremity amputation did not change over 11 years.^[3] Therefore patients should not be referred for surgery or balloon angioplasty unless the symptoms are interfering with their occupation or lifestyle or there are symptoms and signs of ischemia at rest.

General measures include advice to quit smoking and referral to a cessation program if needed. A graded exercise regimen improves walking distance in about 80% of patients. Patients are instructed to keep their feet warm, clean, and dry; toenails should always be cut straight across. Extremes of temperature should be avoided, since ischemic tissue burns at lower temperatures and is more susceptible to frostbite. Cuts or severe bruises on the limbs and feet should be reported to the physician immediately. Obesity and carrying bundles shorten the walking distance before symptoms, since the muscles receive only enough blood flow for a certain amount of work.

Most vascular specialists consider vasodilator drugs not to be of value. Pentoxifylline purportedly increases blood flow by a decrease in blood viscosity and has been reported to produce a small increase in walking distance. The recommended dosage is 400 mg three times a day with nausea and dyspepsia as side effects. Three meta-analyses have been done; two found pentoxifylline of questionable value, while the other reported it of benefit.^[4] Cilostazol is a phosphodiesterase inhibitor that suppresses platelet aggregation and dilates arteries. It has been shown to significantly increase walking distance in patients with claudication at doses of 50 to 100 mg. Patients must be observed carefully for tachycardia; other frequent side effects are headache, diarrhea, dizziness, and nausea.^[5]

The treatment of thromboangiitis obliterans is similar to that for arteriosclerosis obliterans except sympathectomy may be helpful in cases with severe vasospasm and smoking must be stopped. Vignette: An 85-year-old woman presents with limb-threatening ischemia^[6] and a history of angina. The left leg is pale and cool, the toes are purplish. A vascular surgeon is consulted immediately and recommends an aortogram. An amputation in this patient is associated with a high mortality and, if successful, markedly decreases the quality of life. The aortogram shows a tight stenosis of the left external iliac artery and an occluded superficial femoral artery; the right iliac arteries are patent. Consultation with the interventional radiologist results in a successful balloon dilation and stenting of the iliac artery lesion. The left leg becomes warm and the toes pink. The patient is able to walk 100 yards without leg pain. Six months later, left foot pain recurs at rest. Consultation with the vascular surgeon results in an aortogram showing occlusion of the left common and external iliac arteries. The interventional radiologist explains that this lesion cannot be dilated. An anesthesiologist is consulted who recommends epidural anesthesia, which allows greater safety for surgery in the elderly. The vascular surgeon chooses to perform a femorofemoral bypass to supply the left leg, since the right iliac arteries are patent. He prefers this approach, although an axillofemoral bypass would be an alternative option. A cardiologist is consulted who recommends a dobutamine stress test and then clears the patient for surgery since it does not show reversible ischemia. Following surgery, the left leg again becomes warm and of good color. The patient's recovery is slow, and she finds it difficult to walk because of incisional discomfort. A physical therapist is consulted who recommends transfer to a rehabilitation unit where she works with the patient daily on walking and then stair climbing. In 10 days the patient is fully ambulatory and able to live independently because of the close collaboration of the primary care physician, vascular surgeon, anesthesiologist, cardiologist, and physical therapist.

[edit] ARTERIAL EMBOLI AND ACUTE THROMBOSIS

[edit] Epidemiology and Etiology

Typically in this disorder the patient calls the physician because of the sudden onset of severe leg pain that is secondary to abrupt interruption of the arterial supply by an embolus or acute thrombosis of a diseased blood vessel. In the differential diagnosis an embolus is unlikely if a source cannot be found (Box 70-1), and an acute thrombosis is likely if other evidence of chronic obstructive arterial disease is present. Paradoxical emboli originate from venous thromboses, travel to the right side of the heart, and reach the peripheral circulation through the foramen ovale. Emboli may also occur from thrombi in aneurysms or from atheromatous ulcers in any proximal vessel. Atheromatous emboli are often caused by catheterization procedures. Acute thrombosis of an artery usually occurs in a patient with stenosed blood vessels due to arteriosclerosis obliterans.

[edit] Pathophysiology

The clinical picture relates to the acute loss of blood supply to the distal extremity. The symptoms and signs are due to the lack of oxygen and the accumulation of toxic metabolites in the limb. In patients with atheromatous emboli, small vessels in skin and muscle are occluded by cholesterol crystals and atheromatous debris.

[edit] History

In 50% of patients, embolism or acute thrombosis of large or medium-sized arteries produces the sudden onset of severe pain in the extremity. The remaining patients complain of a more insidious onset of pain over several hours. Paresthesias and numbness are present in the majority of patients; muscular weakness or paralysis occurs in one of five cases. The pain is usually unrelenting. However, in patients with acute thrombosis of previously diseased arteries, collateral vessels may already be well developed and the symptoms may abate. Questions about the possible etiologies (e.g., heart disease, peripheral vascular disease, rhythm disturbances) are appropriate.

[edit] Physical Examination

Emboli usually lodge at bifurcations of arteries, and therefore the most common sites are the superficial femoral artery– deep femoral artery junction, the aorta at the origin of the iliac arteries, and the popliteal artery above the trifurcation of medium arteries to the calf. Distal to the embolus the extremity is cold, pale, and pulseless, and the veins are collapsed. The muscles may be tender. These manifestations are usually sharply demarcated at some distance distal to the embolus (e.g., the lower third of the thigh in femoral artery embolus).

Small atheromatous emboli produce a typical clinical picture. One or more digits may be cyanotic (blue toe syndrome), petechiae or ecchymoses may be apparent on the distal limb and foot, livedo reticularis is often present, and elevated reddened plaques may appear on the skin. The muscles are usually tender and the extremities cool, but pulses are often present and normal. If collateral circulation is inadequate, hemorrhagic blebs and gangrene may form.

In acute thrombosis of an artery, the clues to diagnosis are an absence of pulses in the unaffected extremity, a history of intermittent claudication, and the absence of a source of emboli.

[edit] Laboratory Studies and Diagnostic Procedures

The clinical picture of acute embolism or thrombosis is usually typical, and special tests are not needed. Devices that detect extremity pulsations show no pulsations. Ankle systolic pressure measured with a Doppler technique is absent (no arterial sounds detected) or very low. In microemboli a source may not be apparent. Atheromatous blood vessels may need to be sought by arteriography and aneurysms by ultrasound studies. In difficult diagnostic cases skin or muscle biopsy shows cholesterol crystals. In acute thrombosis arteriography shows the diseased blood vessels and the site of thrombosis.

[edit] Prognosis

The prognosis for patients with acute arterial embolism depends heavily on their underlying disease and the high incidence of recurrent emboli.^[7] The mortality in most series is more than 20% because of these factors. The prognosis for a given limb depends on the vessel size, patient age, and ischemic time before operation. Larger vessel emboli (aortoiliac) require surgery or gangrene ensues. Smaller vessels may be managed with watchful waiting.

[edit] Management

A vascular surgeon should be consulted as soon as possible. Anticoagulation with heparin is started to prevent thrombus formation and recurrent embolization. Thrombolytic therapy may be used before anticoagulation and is successful in about one third of patients. The affected extremity is placed in the dependent position and the body and limb kept warm. Heat should not be applied directly to the extremity, since ischemic tissues burn at lower temperatures than normal tissue. Adequate analgesia must be given, since the pain is often intense. If conservative therapy does not improve the color and temperature of the extremity or the pain in 1 to 4 hours, and if the patient is stable, embolectomy is indicated. Following embolectomy, anticoagulation must be reinstituted.

Treatment of an acute occlusion of an artery narrowed by arteriosclerosis can be conservative with bed rest, anticoagulation, and analgesics. If the limb improves, no further therapy is necessary. If rest pain continues, vascular surgery may be necessary. If thrombolytic therapy is used and successfully dissolves the thrombus, the stenosed vessel must be dilated by angioplasty or bypassed to prevent recurrence.

The treatment of atheromatous emboli is often unsatisfactory. Anticoagulation with heparin or administration of antiplatelet agents has been advocated. Warfarin is usually avoided, since it has been implicated as a cause of the emboli.

[edit] ERYTHROMELALGIA

Patients with erythromelalgia complain of burning pain associated with a bright red color of the feet and, less commonly, the hands on exposure to warmth, on dependency of the limb, or during exercise.^[8] It may occur idiopathically or be associated with hypertension, thrombocythemia, lupus erythematosus, or myeloproliferative diseases. There is no age or sex predilection. There is evidently a hypersensitivity of the skin to heat, but when a high platelet count is present, prostaglandins or thromboxane may be involved because aspirin relieves the pain. The attacks of burning pain may be mild to disabling, and often occur in bed at night. During an attack the affected areas are warm, red, very sensitive, and may sweat profusely. Arterial pulses are normal. Cyanosis and necrosis of the toes can occur in thrombocythemia. Attacks can be produced by exposure of the limb to 32° to 36° C water, dependency of the limb, or venous engorgement. Peripheral neuropathies should be ruled out; the dependent rubor of obstructive arterial disease is associated with a cold, pulseless foot. Attacks may be relieved by elevating the extremity and cooling. Treatment is generally unsatisfactory, requiring large doses of sedatives.

[edit] RAYNAUD'S PHENOMENON

[edit] Epidemiology and Etiology

Raynaud's phenomenon includes episodic, ischemic attacks of the digits induced by cold or emotional stimuli.^[9] If no underlying cause can be found, the phenomenon is considered primary Raynaud's phenomenon. The primary syndrome occurs more frequently in females and is much more common than the secondary causes of the phenomenon. It may be present in as many as 16% of young women in cool climates. The onset of attacks is usually between puberty and 40 years of age. Raynaud's phenomenon may be secondary to a number of underlying causes, most of which involve ischemia or trauma to the digital tissue or its nerve or vascular supply (Box 70-2).

[edit] Pathophysiology

Evidence points to a local fault in the digital vessels, causing them to be abnormally reactive to cold; this local problem can be aggravated by a normal amount of reflex sympathetic nerve activity. The initial pallor of the attacks is due to digital artery vasoconstriction; this may be followed by cyanosis due to slow blood flow. When the vessels reopen, a reactive hyperemia occurs, imparting a bright red color to the digits. During the first phase numbness is usual; the patient often describes the part as dead. Pain is more common in the reactive hyperemic stage.

[edit] History

In Raynaud's phenomenon the patient may have only sharply demarcated blanching or cyanosis, or all three color changes, during attacks (Fig. 70-1). At first only one or two fingers may be affected, but later all fingers of both hands are involved. Episodes may last minutes to hours; they may terminate spontaneously or by warming the digits. The fingers are affected alone in the majority of cases, the fingers and toes next in frequency, and only the toes in few patients.

Figure 70-1 Well-demarcated pallor of the fingers occurring during episodes of cold exposure in a young woman with Raynaud's phenomenon.

[edit] Physical Examination

Between attacks the digits appear normal in the primary form. Arterial pulses are normal. Trophic changes appear in progressive cases with the development of sclerodactyly. This is characterized by thin, tapering, contracted fingers with smooth, tight skin. Recurrent painful digital infections, blisters, and small areas of gangrene may occur. In patients showing these trophic changes, scleroderma may be present, although positive tests or other symptoms or signs may not appear until many years later. Patients with obstructive arterial diseases have an absence of pulses in the afflicted extremity. The attacks in patients with other secondary causes have no distinguishing features.

[edit] Laboratory Studies and Diagnostic Procedures

Important laboratory tests include the white blood cell count, hemoglobin, erythrocyte sedimentation rate, protein electrophoresis, urinalysis, complement levels, and tests for antinuclear antibodies and rheumatoid factor. In some cases cold agglutinins and cryoproteins are sought. The capillaries of the fingernail fold can be examined under a microscope. In scleroderma, mixed connective tissue disease, and dermatomyositis there are enlarged, deformed capillary loops surrounded by avascular areas, and hemorrhages may be present. The capillaries are normal in the primary syndrome.

[edit] Differential Diagnosis

Raynaud's phenomenon is often diagnosed from the history of well-demarcated color changes of the digits on exposure to cold, since attacks are difficult to induce in the physician's office. The diagnosis of primary Raynaud's phenomenon depends on exclusion of all secondary causes. A careful history and physical examination eliminates the drug-or work-related cases and elicits symptoms and signs of connective tissue diseases or occlusive arterial disease.

Patients who present with an unevenly blue-red discoloration of the digits that can extend to the wrists and ankles have acrocyanosis.^[10] The etiology is unknown but is probably a vasospastic disturbance of the cutaneous arterioles due to cold hypersensitivity. Acrocyanosis has no special age or sex incidence; it may be associated with various endocrine diseases. The blue discoloration appears in cool environments; the hands usually sweat profusely and are persistently cool. The hands and/or feet are symmetrically involved. The digits may swell and mild hypesthesia may be present, but trophic changes do not occur. Acrocyanosis can be distinguished from Raynaud's phenomenon by the persistent nature of the discoloration in the former entity.

[edit] Prognosis

In primary Raynaud's phenomenon about one sixth of the patients improve or even recover, about one third progress, and the rest remain stable. The progressive form with sclerodactyly, recurring infection, or local gangrene can become a disabling, painful disease, but distal digital loss occurs in fewer than 1%. The prognosis for secondary Raynaud's phenomenon depends on the underlying cause.

[edit] Management

In most patients with primary Raynaud's phenomenon reassurance that the prognosis is benign and an explanation of the attacks is the only treatment necessary. The body and extremities must be kept warm to prevent reflex sympathetic vasoconstriction. Loose-fitting warm clothing should be worn. Tobacco smoking is discouraged because it causes cutaneous vasoconstriction, which aggravates the underlying disease. If these measures fail to allow the patient to engage in usual activities, drug therapy may be tried; it is palliative in approximately two thirds of patients. Nifedipine, a calcium channel blocker, decreases the frequency, severity, and duration of vasospastic attacks and is the most effective treatment. However, some patients cannot tolerate the side effects of headache, anxiety, nausea, edema, and reflex tachycardia. The extended action tablets (30 to 90 mg) given once daily have fewer side effects. Prazosin, an α-receptor blocker, 3 to 6 mg daily, may also be tried; side effects include dizziness, headaches, drowsiness, palpitations, and nausea. Although lumbar sympathectomy has successfully alleviated Raynaud's phenomenon involving the feet, cervicodorsal sympathectomy for the finger symptoms is not recommended. Symptoms usually return within 6 to 24 months after upper extremity sympathectomy.

[edit] LIVEDO RETICULARIS

In livedo reticularis the patient presents with a painless, reddish blue mottling of the skin of the extremities (reticular pattern, fishnet) or rarely on the trunk of the body on exposure to cold environments or during emotional upsets.^[9] In the idiopathic type, there are no other physical findings or diagnostic tests. The blanched areas of skin are believed secondary to vasospasm of the perpendicular arterioles that perforate the skin from the subcutaneous tissue. The bluish periphery around the blanched area is caused by deoxygenated blood in the surrounding horizontally arranged venous plexuses. Besides the idiopathic type, livedo reticularis may accompany other vasospastic diseases or be a clue to systemic disease (Box 70-3). In the idiopathic type no treatment except reassurance is necessary. Rare patients develop cutaneous ulcerations in the winter, or even the summer. These patients actually have an underlying vasculitis for which no treatment has proved satisfactory.

[edit] POSTPHLEBITIC SYNDROME AND VARICOSE VEINS

[edit] Epidemiology and Etiology

The postphlebitic syndrome is a chronically swollen limb often with stasis dermatitis, subcutaneous tissue induration, and ulcerations.^[11] It can appear soon after phlebitis or 10 to 20 years later and is due to incompetent superficial or deep veins.

Varicose veins are distended, tortuous veins with incompetent valves that may appear following phlebitis or pregnancy or with no apparent instigating cause.^[10]

[edit] Pathophysiology

High venous pressure in the limb due to incompetent venous valves leads to capillary leakage of fluid and red blood cells. The tissue reacts to the hemoglobin from red blood cells with inflammation and fibrosis. A brown pigmentation occurs from the inflammatory reaction and deposition of hemoglobin. Ulceration is probably the result of stasis of blood with ensuing hypoxia of the tissue.

Varicosities are due to incompetent venous valves as a result of high venous pressure distending and stretching the veins or to destruction of the valves from thrombophlebitis. For the pathophysiology of ulcers see Chapter 93 .

[edit] History

Patients with the postphlebitic syndrome have a chronically swollen extremity. Often medical care is not sought until very advanced disease with ulcers is present because of the absence of pain. Aching pain in the leg may occur after long periods of standing.

Most patients with varicose veins have no symptoms, whereas others complain of fatigue or aching in the lower part of the leg or swelling at the end of the day.

[edit] Physical Examination

In the postphlebitic syndrome varicose veins are usually present. The edema is pitting but later may become indurated. An itchy, inflamed, scaly rash above or below the medial malleolus is followed by brown pigmentation of the area and finally ulceration.

Varicose veins can be seen as dilated, tortuous, sacculated superficial veins.

[edit] Laboratory Studies and Diagnostic Procedures

The clinical picture of the postphlebitic syndrome almost always is diagnostic. When the diagnosis is in doubt, a venogram shows the involved leg to contain an excessive number of veins often with valve destruction and a feathery appearance of the lining of some veins indicating previous phlebitis.

The incompetent valves of varicose veins can be demonstrated by applying a tourniquet on an elevated extremity so that the superficial veins are empty. The patient then stands; release of the tourniquet allows the vein distally to enlarge quickly if incompetent valves are present. If two tourniquets are applied, filling of the saphenous vein between the tourniquets delineates incompetent communicating (perforating) veins.

[edit] Differential Diagnosis (Table 70-2)

The postphlebitic syndrome should not be confused with lymphedema. Patients with lymphedema do not usually have varicose veins, stasis pigmentation, or ulcers. Venograms or lymphangiograms are rarely necessary in the differential diagnosis.

Table 70-2 Differential Diagnosis of the Swollen Limb

[edit] Management

Postphlebitic syndrome is difficult to treat and requires patient compliance. Heavy-gauge elastic support (30 mm Hg or greater) must be worn when the patient is ambulatory. Patients must usually sleep with the foot of the bed elevated above heart level to keep edema to a minimum. In elderly patients, especially with arthritis, some arrangement must be made to help them put on the stockings.

Uncomplicated varicose veins respond well to heavy-gauge elastic stockings. This prevents symptoms, edema, and further enlargement of the veins. Panty girdles or garters are never worn. Ligation and stripping of veins have decreased in popularity, since the veins may be needed in the future for arterial bypass.

[edit] LYMPHEDEMA

[edit] Epidemiology and Etiology

Lymphedema is a chronically swollen, painless limb^[12] (see Box 70-4).

[edit] Pathophysiology

The chronic swelling of the limb is due to aplasia, hypoplasia, or varicosities of the lymphatic vessels that drain the tissue fluid. Subcutaneous fibrosis of the edematous tissue gradually occurs.

[edit] History

The swelling in lymphedema is usually gradual in onset and asymptomatic. Some patients do complain of a heaviness and pain. Patients should be questioned about a family history of leg swelling, episodes of cellulitis, radiation therapy, surgery, and travel to areas where filariasis is common. Recurrent lymphangitis can lead to lymphedema, and extremities inflicted with lymphedema are very susceptible to recurrent episodes of cellulitis.

[edit] Physical Examination

Lymphedema first involves the distal extremity or the entire limb and is soft, pitting, and reversible. Later the edema becomes indurated and nonpitting, the skin thickens and resists wrinkling, and hair follicles become prominent dimples. The skin finally becomes coarse, thick, folded, and hard; the extremely disfigured extremities have been aptly termed elephantiasis. The lower extremities are involved most often, and approximately 50% of patients have bilateral swelling. Secondary lymphedema usually involves only one extremity.

[edit] Laboratory Studies and Diagnostic Procedures

Lymphoscintigraphy may confirm the diagnosis but is usually not necessary.

[edit] Differential Diagnosis

Painless, chronic swelling of an extremity, without varicosi-ties, stasis dermatitis, and collateral veins are diagnostic of lymphedema. In lipodystrophy the subcutaneous tissue of the legs feels nodular; lymphoscintigraphy is necessary to demonstrate the normal lymphatics displaced by lipomatous masses.

[edit] Management

With lymphedema it is important to attempt to keep the involved extremities as free from edema as possible to prevent subcutaneous fibrosis and skin thickening as well as recurrent episodes of lymphangitis. Heavy surgical elastic support garments (30 to 50 mm Hg) covering the entire involved area with graded pressure from distal to proximal extremity must be worn whenever ambulatory. The patient should sleep with the involved extremity above heart level. In late, disfiguring cases surgical removal of the subcutaneous tissue has been performed, but it is itself a very disfiguring operation.

[edit] LYMPHANGITIS

[edit] Epidemiology and Etiology

In most cases of infection of the lymphatic vessels the agent is the hemolytic streptococcus or the coagulase-positive staphylococcus. Although a portal of entry for the bacteria is not always apparent, fungal infections of the toes are commonly present.

[edit] Pathophysiology

The bacterial infection spreads along lymphatics with an inflammatory response often spreading to surrounding tissues (cellulitis).

[edit] History

Patients often show systemic symptoms of infection: fever, shaking, chills, headache, general malaise, nausea, and vomiting.

[edit] Physical Examination

Red streaks appear, following the pathways of lymphatic vessels, and proximal lymph nodes are often enlarged and tender. The limb may be swollen, and there may be diffuse redness, increased temperature, and tenderness indicative of cellulitis.

[edit] Laboratory Studies and Diagnostic Procedures

The clinical picture is usually typical. Leukocytosis with a left shift in polymorphonuclear cells may be present. Culture of any open lesion may yield the inciting organism.

[edit] Management

Broad-spectrum antibiotics are administered in high doses intravenously until culture reports are obtained. Debridement or drainage of any focus of origin is also very important. Bed rest and extremity elevation may hasten healing by decreasing edema. In recurrent cases, especially with underlying lymphedema, a prophylactic antibiotic, usually penicillin, is administered on a long-term basis.

[edit] REFERENCES