51. Lymphangitis, lymphadenitis and elephantiasis

1. Definition

• Lymphangitis → acute inflammation of lymphatic vessels, usually bacterial, spreading from a skin wound or infection
• Lymphadenitis → inflammation of lymph nodes (acute or chronic), usually draining an infected area
• Lymphoedema → swelling from build-up of protein-rich fluid in the tissues, due to poor lymph drainage
• Elephantiasis → end stage of chronic lymphoedema: huge limb with thick, fibrotic, warty skin

2. Epidemiology

• Lymphangitis and acute lymphadenitis → common; follow minor wounds, cellulitis, abscesses
• Secondary lymphoedema → most common form worldwide:
  • Developed countries → after cancer treatment (axillary or groin dissection, radiotherapy); about 20% after axillary clearance
  • Worldwide → filariasis (over 100 million infected in tropical Asia, Africa, South America)
• Primary lymphoedema → rare (about 1 in 6,000–10,000); more in women

3. Aetiology and risk factors

Lymphangitis and acute lymphadenitis

• Streptococcus pyogenes (most), Staphylococcus aureus
• Entry → cuts, insect bites, tinea pedis (athlete's foot), ingrown nails, abscesses
• Risk factors → diabetes, immunosuppression, lymphoedema, venous disease
• Rare → cat-scratch disease (Bartonella), sporotrichosis, Pasteurella

Chronic lymphadenitis

• Tuberculosis (scrofula, neck) → most common cause of chronic lymphadenitis in endemic areas
• Atypical mycobacteria (children), actinomycosis, HIV, syphilis, toxoplasmosis

Lymphoedema

• Primary → failure of lymph vessel development:
  • Congenital (< 1 year, 10%) → familial form = Milroy's disease
  • Praecox (1–35 years, 80%) → familial form = Meige's disease, around puberty
  • Tarda (> 35 years, 10%)
• Secondary:
  • Surgery → axillary, groin or pelvic node dissection
  • Radiotherapy
  • Tumour invasion of nodes
  • Filariasis → Wuchereria bancrofti, Brugia malayi; mosquito-borne
  • Recurrent cellulitis and lymphangitis
  • Trauma, burns
  • Podoconiosis → barefoot contact with volcanic soil
  • Obesity, chronic venous disease (phlebolymphoedema)

4. Pathogenesis

Lymphangitis and lymphadenitis

1. Bacteria enter through a break in the skin
2. Spread along superficial lymph vessels → red streaks towards the regional nodes
3. Nodes swell, become tender → lymphadenitis
4. Node may suppurate → abscess; bacteria pass the node → bacteraemia, sepsis

Lymphoedema

1. Lymph flow blocked or absent
2. Protein-rich fluid collects in the tissue
3. Protein draws in more water; macrophages and fibroblasts arrive
4. Chronic inflammation → fibrosis and fat deposition
5. Skin thickens; immunity in the limb falls → recurrent infections
6. Each infection destroys more lymphatics → vicious cycle → elephantiasis

Filariasis

• Adult worms live in lymph vessels and nodes → inflammation, blockage
• Acute attacks (filarial fever, lymphangitis) → chronic lymphoedema, hydrocele, chyluria

5. Classification

Lymphangitis

• Acute (reticular, tubular)
• Chronic → recurrent attacks in lymphoedema, fungal, mycobacterial

Lymphadenitis

• Acute (simple, suppurative → abscess)
• Chronic (non-specific, specific: tuberculosis, syphilis, actinomycosis)

Lymphoedema (International Society of Lymphology)

• Stage 0 → latent; lymph transport impaired, no swelling
• Stage I → pitting oedema; settles with elevation
• Stage II → non-pitting; does not settle with elevation; fibrosis
• Stage III → elephantiasis: fibrosis, fat, warty skin (papillomatosis), skin folds

6. Clinical picture

Symptoms

• Lymphangitis → painful red streaks spreading up the limb from a wound; fever, rigors, malaise
• Acute lymphadenitis → painful, tender swollen nodes (groin, axilla, neck)
• Abscess → throbbing pain, fluctuant swelling
• Tuberculous lymphadenitis → painless, slow-growing, matted neck nodes; may form a cold abscess and sinus ("collar-stud" abscess)
• Lymphoedema → heavy, swollen limb; starts distally; little pain

Signs

• Lymphangitis → tender red lines; surrounding cellulitis
• Lymphadenitis → tender, warm, enlarged nodes; fluctuation if suppurating
• Lymphoedema:
  • Starts at the foot; swelling of the dorsum ("buffalo hump")
  • Stemmer's sign → cannot pinch a fold of skin at the base of the second toe
  • Square toes
  • Pitting early; non-pitting later
  • Thick, rough skin, hyperkeratosis, papillomas, deep folds
  • Lymph leak (lymphorrhoea), fungal infection between toes
  • No ulcers and no pigment (unlike venous disease)

7. Diagnosis

Acute infection

• Clinical diagnosis
• FBC, CRP; blood cultures if systemically unwell
• Swab or pus culture
• Ultrasound → node abscess

Chronic lymphadenitis

• Fine-needle aspiration or excision biopsy → tuberculosis, lymphoma, metastases
• Acid-fast stain, culture, PCR; chest X-ray

Lymphoedema

• Clinical in stages II–III
• Lymphoscintigraphy → test of choice: radioactive tracer injected into the web space; shows slow or absent transport, dermal backflow
• Indocyanine green (ICG) lymphography → maps superficial lymphatics before surgery
• MRI or CT → exclude pelvic or abdominal tumour (new lymphoedema in an adult)
• Duplex → exclude venous disease
• Filariasis → night blood smear (microfilariae), antigen test, ultrasound ("filarial dance" sign)
• Limb volume measurement → follow-up

8. Differential diagnosis

• Lymphangitis versus superficial thrombophlebitis, cellulitis, necrotising fasciitis
• Lymphadenitis versus lymphoma, metastatic nodes, hernia (groin), cyst
• Lymphoedema versus:
  • Venous oedema (pigment, ulcers, varicose veins)
  • Lipoedema → both legs, fat, spares the feet, women
  • Heart, kidney, liver failure, hypoproteinaemia (both legs, pitting)
  • Myxoedema
  • Deep vein thrombosis

9. Treatment

Conservative

• Lymphangitis and acute lymphadenitis:
  • Antibiotics → flucloxacillin or penicillin (co-amoxiclav, clindamycin in allergy)
  • Rest, elevation, analgesia
  • Treat the portal of entry (wound, tinea pedis)
  • IV antibiotics if septic or not responding
• Tuberculous lymphadenitis → antituberculous drugs for 6 months
• Lymphoedema → no cure; aim to reduce swelling and prevent infection:
  • Complete decongestive therapy:
    1. Manual lymphatic drainage (massage)
    2. Multilayer compression bandaging
    3. Exercise
    4. Skin care
  • Then compression garments for life (class III–IV)
  • Elevation, weight loss
  • Intermittent pneumatic compression
  • Skin hygiene, emollients, antifungals
  • Prophylactic penicillin → recurrent cellulitis (≥ 2 attacks a year)
  • Diuretics → no role (only short-term effect)
• Filariasis → diethylcarbamazine, albendazole, ivermectin; mass drug treatment; hygiene and limb care

Surgical

• Lymph node abscess → incision and drainage; send pus for culture
• Tuberculous cold abscess → aspirate through a non-dependent site; excise nodes if drugs fail or sinus persists
• Lymphoedema surgery (stage II–III, when conservative care fails):
  • Physiological (restore drainage; early disease):
    • Lymphovenous anastomosis (bypass)
    • Vascularised lymph node transfer
  • Reductive / excisional (late disease):
    • Liposuction → removes fat in non-pitting lymphoedema; needs lifelong compression
    • Staged subcutaneous excision under flaps (Homans', Sistrunk)
    • Charles' operation → excise all skin and subcutaneous tissue down to the deep fascia; cover with split-skin grafts; for elephantiasis
• Filarial hydrocele → excision of the sac (hydrocelectomy)

10. Complications

• Lymphangitis → cellulitis, abscess, sepsis, necrotising fasciitis (rare)
• Lymphadenitis → abscess, sinus, scarring
• Lymphoedema:
  • Recurrent cellulitis
  • Disability, psychological distress
  • Lymphorrhoea, skin breakdown
  • Lymphangiosarcoma (Stewart-Treves syndrome) → rare, aggressive tumour after > 10 years of lymphoedema (classically arm after mastectomy)
• Charles' operation → poor cosmetic result, graft breakdown, hyperkeratosis, amputation in severe cases