Synopsis
Recognise painful calcific arteriolopathy before black necrosis appears, distinguish it from infection and other retiform disease, and coordinate urgent renal, wound, analgesic, metabolic and infection management despite limited treatment evidence.
- Calciphylaxis is calcific uraemic arteriolopathy: an uncommon, intensely painful occlusive small-artery disease seen mainly in advanced CKD and dialysis, although non-uraemic cases occur.
- Deep burning pain and firm woody subcutaneous induration can precede visible change; lesions evolve through mottled livedoid or retiform purple-grey plaques to ulcer and black eschar.
- On brown or black skin, early colour may be deep violet, grey-brown or subtle; exquisite focal pain, hardness, temperature and an angular vascular outline should trigger examination under good light and touch.
Key red flags
Pain out of proportion, rapidly enlarging livedoid or retiform plaques, black eschar, new systemic illness, crepitus, hypotension, exposed deep tissue, genital involvement, uncontrolled opioid-resistant pain or acute tissue ischaemia requires same-day multidisciplinary escalation.
A painful irregular ulcer exposes yellow-black fat and develops adherent black eschar, with a high risk of bacterial invasion and sepsis.
Investigation priorities
Recognise the syndrome early and document distribution before ulceration obscures the active edge.
Management branches
A dialysis or high-risk patient develops new focal severe skin pain, hardness or livedoid change.
- Examine the complete painful region and all skin with consent, document depth, temperature, retiform outline and infection and assess ABCDE and limb perfusion.
- Contact nephrology and dermatology the same day and involve tissue viability and pain specialists before waiting for ulceration or a biopsy appointment.