Calciphylaxis

Background

• Most commonly HD/ESRD patients (1% of ESRD)
  • Seen almost exclusively in patients with Stage 5 chronic kidney disease
• No available data in general population (non-uremic calciphylaxis)
• Calcium and phosphate levels rise beyond solubility and precipitate in arteries
• May be increasing due to widespread IV vitamin D
• Mortality as high as 60-80%; sepsis from necrotic skin lesions

Features

• Very painful lesions develop suddenly and progress rapidly
• Dermatolgic appearances:
  • Livedo reticularis
  • Stellate purpura
  • Usually LEs, hands, or torso

Differential Diagnosis

• Brown recluse spider bite
• Bullous Pemphigoid
• Cellulitis, necrotizing fasciitis
• Erythema Nodosum
• Vasculitis
• Venous ulcers
• Hypercalcemia
• Hyperphosphatemia
• Nephrogenic systemic fibrosis (MRI w/ gadolinium in dialysis pt)

Diagnosis

Labs

• Serum PTH level
• CBC, CMP, phosphate, coags
• Inpatient - hepatitis panel, cryofibrinogen level, lipase, ESR, CRP, ANA, ANCA

Imaging

• Plain radiographs - arborization of vascular calcification within dermis and subQ tissues

Management

• Rigorous and continuous control of phosphate and calcium balance
• Medical
  • Discontinue calcium increasing interventions
  • Increase dialysis frequency
  • Calcimimetics in hyperparathyroidism
  • Bisphosphonates
  • Sodium thiosulfate - off-label, increases solubility of calcium deposits
  • Fix hypercoagulability
  • Surgical
• Aggressive wound care and debridement of necrotic tissues
  • Wound VAC
  • Total or subtotal parathyroidectomy