Vasculitis (Inflammation of Blood Vessels)

Vasculitis is an inflammation of blood vessel walls that can be limited to the skin (mild, self-limiting) or systemic (life-threatening, multi-organ). Patients present with symptoms of systemic inflammation + organ dysfunction.

A. Cutaneous Small-Vessel Vasculitis (Skin-Focused):

• Onset: Abrupt crop of lesions, often following a trigger (new drug, recent infection).

• Symptoms: "Spots" or "bruises" on the legs that are raised and tender. Burning, pain, or itch at the lesion sites.

• Distribution: Primarily on the lower legs, often worsened by prolonged standing/walking.

• Warning Signs: Joint pains, abdominal pain, or haematuria suggest a systemic form (e.g., IgA vasculitis, ANCA-associated).

B. General/Systemic Vasculitis (The "Organ Damage" Clues):

• Constitutional: Fever, malaise, unintentional weight loss.

• Renal: Dark/bloody urine, frothy urine, or oedema (suggests glomerulonephritis).

• Respiratory: Cough, haemoptysis (coughing blood), chronic sinusitis, or nosebleeds.

• Vascular/Neurological: Digital ulcers, claudication, sudden visual loss (GCA), or peripheral neuropathy (foot/wrist drop).

Crucial Note for Darker Skin Tones:

• Patients rarely describe "redness"; they report “dark purple/brown marks” or “bruise-like spots.”

• It is essential to ask if the bumps feel raised to the touch and if old lesions leave behind persistent dark staining (haemosiderin).

A. Skin Examination (Small-Vessel Vasculitis):

• Key Finding: Palpable Purpura (the hallmark): Non-blanching, raised purplish papules/plaques, predominantly on the lower legs.

• Other Features: Urticarial-like lesions that evolve into purpura, haemorrhagic bullae, or superficial ulceration in severe cases.

• Capillaritis: Pinpoint petechiae with a rusty/orange-brown stain (haemosiderin) suggesting chronic leakage.

B. Systemic Examination (Look for Organ Involvement):

• Vitals: Check blood pressure in both arms (discrepancy may suggest large-vessel disease).

• Eyes: Check for conjunctival injection, uveitis, or visual acuity (GCA).

• ENT: Look for nasal crusting or septal perforation.

• Neurology: Assess for peripheral neuropathy or focal deficits.

• Pulses: Check peripheral pulses for absence or bruits (suggests large-vessel disease).

Key Examination Nuances in Darker Skin Tones:

• Colour: Purpura appears dark red, violaceous, brown, or almost black rather than bright purple.

• Haemosiderin Staining: The residual orange-brown to dark brown patches that persist after the acute rash are highly noticeable.

• Palpation is Key: Since the color change is subtle, always run fingers over the lesions—the raised texture of palpable purpura confirms the diagnosis regardless of skin tone.

• Treatment is dictated by whether the disease is skin-limited or systemic/organ-threatening.

• 1. General Principles (Crucial First Steps):

• Identify/Remove Trigger: Stop all suspected new medications (especially antibiotics, NSAIDs) and treat underlying infections (Hepatitis B/C).

• Assess Systemic Risk: Perform a complete systemic review (including urinalysis for haematuria).

2. Cutaneous Small-Vessel Vasculitis (Skin-Limited):

• Supportive Care (First-line for mild, first episode):

  • • Rest and Leg Elevation: Avoid prolonged standing.

    • Compression stockings (if tolerated and ischaemia is excluded).

    • Simple analgesia; careful wound care for ulcers.

• Active Immunomodulation (For severe, recurrent, or ulcerated disease):

  • • Short course oral corticosteroids (e.g., Prednisone 0.5 mg/kg/day, tapered).

    • Steroid-sparing agents (Colchicine, Dapsone).

3. Systemic Vasculitis (Requires Urgent Specialist Care): Managed jointly with Rheumatology/Nephrology.

• Induction: High-dose Glucocorticoids (e.g., Prednisone 40–60 mg/day) plus potent immunosuppressants (e.g., Cyclophosphamide or Rituximab for severe ANCA-associated vasculitis).

• Maintenance: Long-term immunosuppression (Azathioprine, Methotrexate, Rituximab) to prevent relapse.

Darker Skin Tones – Treatment Considerations:

• PIH Counselling: Warn the patient that the post-inflammatory hyperpigmentation (PIH) will persist for months, even after the inflammation clears.

• Sun Protection: Encourage consistent sun protection on the legs to minimize darkening of residual PIH.

Vasculitis – StatPearls (NCBI Bookshelf): https://www.ncbi.nlm.nih.gov/books/NBK545186/

Cutaneous Small Vessel Vasculitis – DermNet: https://dermnetnz.org/topics/cutaneous-small-vessel-vasculitis

Cutaneous Vasculitis – DermNet: https://dermnetnz.org/topics/cutaneous-vasculitis