This is a devastating condition of vascular calcification in ESRD patients, leading to intensely painful, retiform purpura and necrotic ulcers, a different presentation than tender erythematous nodules.
Also known as nodular vasculitis, this condition presents as chronic, ulcerative nodules on the posterior calves, whereas EN nodules are on the anterior shins and do not typically ulcerate.
Exaggerated bite reactions can form nodules, but they are typically pruritic and have a central punctum.
This is a panniculitis in lupus patients, distinguished by deep, firm nodules that often heal with significant atrophy and depression of the skin.
This is a rare form of panniculitis associated with pancreatic disease, characterized by nodules that may suppurate and discharge an oily substance.
Cutaneous PAN presents with tender subcutaneous nodules that often follow the course of an artery and may be associated with livedo reticularis and ulceration.
These are typically asymptomatic, firm, deep nodules, most often in children on the shins or scalp, lacking the acute tenderness of erythema nodosum.
While EN is a reaction pattern, true vasculitis (like PAN) involves inflammation of the vessel wall and presents with more specific signs like livedo reticularis or palpable purpura.