Question

A 50 year old male with rheumatoid arthritis (RA) for 10 years on treatment presents with a non healing ulcer on the lower limb and stocking-glove neuropathy. What is the most likely cause?

• A. RA vasculitis
• B. Drug induced neuropathy
• C. Amyloid neuropathy
• D. Diabetic neuropathy

Hint:

Rheumatoid vasculitis generally affects patients with long-standing ($>$10 years), severe, nodular, and seropositive RA. It is characterized by high titers of Rheumatoid Factor and a sudden decline in joint symptoms while systemic symptoms (fever, weight loss, ulcers, neuropathy) flare up.

Answer 1

The Correct Option is A

Concept:
The presentation of a non-healing lower extremity ulcer and peripheral neuropathy (stocking-glove pattern or mononeuritis multiplex) in a patient with long-standing, treated Rheumatoid Arthritis is the hallmark of Rheumatoid Vasculitis (RV).
RV is a severe, rare, extra-articular complication of long-standing, seropositive RA.
Explanation:

• Rheumatoid Vasculitis involves the inflammation of small to medium-sized blood vessels. It typically arises in patients with a history of severe, erosive, seropositive (high RF and anti-CCP) RA of at least 10 years duration.

• Dermatologic manifestations are the most common, presenting as deep, punched-out, non-healing cutaneous ulcers (particularly on the lower limbs/malleoli), palpable purpura, or digital infarcts.

• Neurological involvement occurs due to vasculitis of the vasa nervorum (blood vessels supplying the nerves). This leads to ischemic nerve damage, manifesting as mononeuritis multiplex (e.g., sudden foot drop or wrist drop) or a symmetric distal sensorimotor neuropathy (stocking-glove pattern).

• Option (B), Drug-induced neuropathy, may occur with certain medications (e.g., leflunomide), but it would not explain the severe, non-healing vasculitic ulcer.

• Option (C), Amyloid neuropathy, can occur in secondary (AA) amyloidosis due to chronic RA, but prominent cutaneous deep ulcers are much more typical of active vasculitis. AA amyloidosis more classically presents with significant proteinuria/nephrotic syndrome.

• Option (D), Diabetic neuropathy, is a common cause of ulcers and neuropathy globally, but in the context of a board question emphasizing a 10-year RA history, RV is the targeted unified diagnosis.
Final answer:
The combination of ischemic skin ulcers and peripheral neuropathy in a long-standing RA patient points precisely to Rheumatoid Vasculitis.