52 M with skin rash and abdominal pain

on
NEET PG Case Study: Autoimmune Vasculitis

NEET PG Case Study: Autoimmune Vasculitis

Case Presentation

You are presented with a 52-year-old male with a known history of Rheumatoid Arthritis (RA). He comes to the clinic with a new-onset rash and significant abdominal pain accompanied by vomiting.

Case Details (Interactive Tabs)

Initial Lab Findings

  • Antinuclear Antibody (ANA): Positive
  • Anti-Ro-52 (SSA): Positive

Skin Examination

Forearm: Multiple, scattered, small, non-blanching, erythematous-to-purpuric macules and papules. Discrete lesions. Minor excoriations proximally.

Trunk/Flank: More extensive rash with numerous non-blanching, erythematous and purpuric macules and papules, often coalescing into larger patches. Highly suggestive of cutaneous vasculitis.

Radiology Findings

CT Scan (Abdomen & Pelvis): Diffuse bowel wall thickening (primarily small bowel) with significant mesenteric stranding and edema. Findings raise concerns for mesenteric vasculitis or enteritis.

">

What are your thoughts?

(This is where students would pause and write down their initial differential diagnoses and reasoning.)

Case Resolution & Diagnosis

  • Final Diagnosis: Autoimmune Vasculitis (likely RA-SLE/Sjögren's overlap or severe RV) with cutaneous and mesenteric involvement.
  • Treatment & Outcome: Patient improved significantly after treatment with IV steroids.

Differential Diagnosis: Rashes (Examples)

It's important to differentiate the patient's rash from other vasculitic or autoimmune rashes:

">HSP Rash Example
">SCLE Rash Example

(Note: These are placeholders. In a live version, you would use actual representative images, perhaps like the ones we searched for earlier.)

Teaching Module: Autoimmune Vasculitis

Autoimmune Vasculitis - An Overview

Vasculitis means inflammation of blood vessels, leading to thickening, weakening, or occlusion. It's often classified by vessel size. In CTDs like RA and SLE, it's often an immune complex-mediated small-vessel vasculitis, but can affect medium vessels too.

Key Points:

  • RV occurs in long-standing, seropositive RA.
  • SLE can affect vessels of any size.
  • Sjögren's can cause cutaneous vasculitis and neuropathy.

Pathophysiology

Key mechanisms include:

  • Immune Complex Deposition: Type III Hypersensitivity. Complexes deposit, activate complement, attract neutrophils, causing damage.
  • Autoantibodies: ANA, Ro-52 (risk factor for extra-articular RA/Sjögren's), RF, Anti-CCP play roles.
  • Cell-Mediated Immunity: T-cells orchestrate the attack.
  • Endothelial Activation: Creates a pro-inflammatory cycle.

This leads to non-blanching purpura (skin) and ischemia/edema (gut).

Clinical Presentation

Highly variable. Includes:

  • Constitutional: Fever, weight loss, fatigue.
  • Cutaneous: Palpable purpura (classic!), ulcers, livedo, nodules.
  • GI: Abdominal pain (intestinal angina), N/V, bleeding, ischemia.
  • Neurological: Mononeuritis multiplex (classic!), peripheral neuropathy, CNS (rare).
  • Renal: Glomerulonephritis.
  • Pulmonary: DAH, ILD.

Overlap syndromes are common.

Lab & Radiology Findings

Labs:

  • ESR/CRP (↑), CBC (anemia), CMP (renal function).
  • Urinalysis (hematuria, proteinuria, casts).
  • Autoantibodies (ANA, Ro-52, RF, Anti-CCP, ANCA, C3/C4).

Radiology:

  • CT Abdomen (Bowel wall thickening, stranding, edema).
  • Angiography (Stenosis, occlusion, aneurysms).

Biopsy: Skin (LCV), Nerve, Kidney, Gut - often definitive.

Management

Goals: Induce remission, maintain, minimize toxicity.

  • Induction:
    • Glucocorticoids: IV Pulse Methylprednisolone -> High-dose oral Prednisolone.
    • Immunosuppressants (Severe): Cyclophosphamide or Rituximab.
  • Maintenance:
    • Low-dose steroids.
    • Azathioprine, Mycophenolate, Methotrexate, Rituximab.
  • Supportive Care: PJP prophylaxis, osteoporosis prevention, BP control, CV risk management.

Flashcards (Click to Flip)

52M RA + Abd Pain/Vomiting/Rash + CT Thickening + ANA/Ro-52+. Dx?
Autoimmune Vasculitis (RA-SLE/Sjögren's Overlap or RV) with Cutaneous & Mesenteric involvement.
Significance of Anti-Ro-52+ in RA?
Increased risk of Sjögren's overlap & Extra-articular features (like vasculitis).
How to clinically ID cutaneous vasculitis rash?
Typically Palpable and Non-Blanching Purpura.
Main mechanism of Lupus Mesenteric Vasculitis?
Immune Complex Deposition -> Complement Activation -> Neutrophil Influx -> Damage.
Foot drop + Wrist drop in RA suggests?
Mononeuritis Multiplex -> Vasculitis (RV).
Cornerstone of initial treatment for severe autoimmune vasculitis?
High-dose Glucocorticoids (IV Pulse).
Prophylaxis needed with high-dose steroids + CYC/RTX?
PJP (PCP) Prophylaxis (e.g., Co-trimoxazole).

NEET PG Style Quiz

Q1. A 55-year-old male with long-standing seropositive RA presents with painful skin ulcers on his legs and new-onset foot drop. ANA is negative. Which is the *most* likely primary diagnosis?

Q2. Which autoantibody, when positive in an RA patient, is particularly associated with an increased risk of developing Sjögren's overlap and vasculitis?

Q3. The *most* characteristic feature of a rash caused by small-vessel cutaneous vasculitis is:

Q4. A patient with SLE is admitted with severe abdominal pain, vomiting, and fever. A CT scan confirms diffuse small bowel wall thickening and mesenteric stranding. What is the *most* appropriate *initial* management step?

Q5. The underlying mechanism responsible for damage in most immune complex-mediated small-vessel vasculitis involves:

Comments

Post a Comment