Lymphedema

Etiology and classification

In surgical practice, lymph outflow disorders are divided into two main forms:

1. Primary form. It develops due to a congenital defect or anomaly in the development of the lymphatic system. It is extremely rare, and the edema is predominantly localized to the lower leg.
2. Secondary (acquired) form. Diagnosed significantly more often. The patency of lymphatic pathways is disrupted as a result of external factors or other diseases.

The main causes of secondary lymphostasis include:

• Inflammatory diseases of the skin and cellular tissue: lymphadenitis, pyoderma, trophic ulcers, and erysipelas (the most frequent cause).
• Traumatic and iatrogenic factors: direct vessel injury, compression of pathways by a hematoma, radiation therapy (scarring compresses collaterals), surgical removal of lymph nodes (e.g., during mastectomy).
• Oncological processes: blockade of lymph nodes by tumor metastases.
• Chronic specific infections: syphilis, tuberculosis.
• Parasitic infestations: filariasis (accompanied by lymphangitis and the formation of persistent edema).

Pathogenesis: how persistent edema develops

The development of lymphedema represents a cascade of successive hemodynamic and structural disorders in the lymphatic bed.

It all begins with a primary outflow disturbance, causing local lymph stasis. Due to increased pressure, lymphatic vessels overfill and significantly dilate. Such overstretching of the wall leads to functional insufficiency of the valve apparatus. As a result, reflux occurs—uncontrolled dumping of lymph into the lower parts of the limb. Stasis is exacerbated, the drainage function of the tissues is completely disrupted, forming persistent edema.

Pathogenesis during inflammation (e.g., in recurrent erysipelas) has a special mechanism. Under the influence of an infectious agent, vessels dilate, then become deformed, and chronic scarring leads to their complete obliteration (overgrowth). Each new relapse of inflammation inevitably increases the area of lymphostasis, ultimately leading to elephantiasis.

Clinical presentation

The symptoms of lymphostasis directly depend on the cause that triggered the pathology.

• Congenital insufficiency: debuts at an early age or during puberty. It manifests as a progressive thickening of the feet, lower legs, and thighs. Initially, patients complain only of a cosmetic defect.
• Traumatic injury: early edema can rapidly increase as early as the second day after surgery, and a persistent clinical picture forms within 6–8 weeks.
• Local inflammatory processes (erysipelas): edema develops very rapidly. Acute phenomena resolve within 5–7 days, but the edema itself disappears extremely slowly.
• Filariasis: begins with enlarged lymph nodes, lymphangitis, and a feeling of heaviness during physical exertion. Edema forms over years.

Skin examination: Visual inspection reveals an increase in the volume of the limb or scrotum. In the early stages, the skin over the affected area is thin, shiny, and smooth. However, once elephantiasis has formed, the epidermis changes drastically: massive papillomatous growths and pronounced hyperkeratosis appear. When complicated by erysipelas, eczema and trophic ulcerations may be observed.

Differential diagnosis

When examining a patient with an increased limb volume, it is critically differentiated to distinguish lymphatic edema from venous edema.

Lymphatic edema:

• Skin is pale.
• Edema is extremely dense: pressing with a finger leaves no pit.
• Superficial varicose veins are absent.
• The main manifestation is a uniform increase in limb volume.

Venous edema:

• Skin is cyanotic, often thinned and atrophic.
• Pigmentation is pronounced, especially in the lower third of the shin.
• Pain syndrome is present.
• Acute deep thrombophlebitis is often found in the anamnesis, with visible signs of chronic venous insufficiency.

To accurately verify lymph circulation disorders, lymphography is used. This is the most valuable diagnostic method in which a radiopaque substance is injected into the lymphatic bed. On the images, the physician assesses the degree of lumen narrowing, pathological dilation, or areas of complete vessel obliteration.

Principles of treatment

Treatment tactics are selected individually depending on the stage of the process.

1. Etiotropic therapy. First of all, it is necessary to relieve the disease that provoked the lymph outflow disorder (treatment of erysipelas, tuberculosis, syphilis).
2. Conservative treatment. Effective in the initial, still reversible period. The patient is recommended a strict limitation of prolonged standing (up to a change of profession). Mechanical impact is prescribed: wearing a pressure bandage, therapeutic exercise (physical therapy), and special massage. Among physiotherapy methods, therapeutic mud and hydrogen sulfide baths are used.
3. Surgical treatment. Prescribed when conservative measures are ineffective or at the stage of elephantiasis.
4. Microsurgical methods: to restore outflow, surgeons create an artificial anastomosis between the lymphatic and venous systems.
5. Plastic surgery: used for pronounced elephantiasis of the extremities or genitals. Scar-altered subcutaneous adipose tissue is completely excised. Then, plastic surgery is performed: skin flaps, freed from fat, are engrafted directly onto the muscular fascia.

Briefly: answers to topical questions

Class and exam questions

What else to study on this topic

• Methodology for radiopaque lymphography
• Microsurgical technique for lymphovenous anastomosis formation
• Features of skin grafting during subcutaneous tissue excision
• Pathogenesis of wuchereriasis and mechanisms of scrotal elephantiasis development
• Mechanisms of functional insufficiency of lymphatic vessel valves

Other topics of 'CHAPTER 13. VASCULAR AND LYMPHATIC INSUFFICIENCY OF THE EXTREMITIES'

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