Moffitt Report Pearls 12/8/17 – painful legs!

Thank you, Hailen, for presenting a case of an older woman with ESRD on PD who presented with a week of progressive pain in her bilateral calves, found to have very tender subcutaneous nodules on exam, a calcium-phosphorus product of ~75, and imaging findings of calcium deposition in the arteries and subcutaneous tissue – putting it all together, concerning for calcemic uremic arteriopathy!

Key Pearls:

  1. The differential diagnosis for subcutaneous nodules is extensive! Starting with a framework to break down categories of disease can be useful, such as primary inflammatory causes, infectious causes (both direct infection and via distant immunephenomena), benign causes, and malignant causes.
  2. Calciphylaxis, now called calcemic uremic arteriopathy is a rare disorder associated with ESRD patients that leads to skin ischemia and necrosis. See more below!

Calcemic Uremic Arteriopathy – check out this 2014 review for more details

  • Thought to develop due to disruption of balance between factors favoring calcification and those preventing pathologic calcification
  • Likely a combination of passive mineralization in setting of high calcium-phosphorus product, as well as abnormal active cellular processes

Hallmarks of Disease:

  • Vasculopathy with extensive medial calcification
  • HIGH risk of cardiovascular mortality

Risk Factors:         #1 CKD/ESRD

  • Demographics: Female sex, white race
  • Comorbidities: Diabetes mellitus, Obesity, Secondary hyperparathyroidism
  • Labs: Calcium-phosphate product > 70, Low serum albumin, Elevated AlkPhos, Protein C and/or S deficiency
  • Time on HD
  • Medications: Vitamin D supplementation, Calcium-based phosphate binders, warfarin, corticosteroids, iron dextran, erythropoietin,

Clinical Presentation:

  • Often initially present as excruciatingly painful subcutaneous nodules with violaceous mottling, similar to livedo reticularis. Lesions generally progress to forming ulcers and eschars as a result of ischemic necrosis.
  • Main body areas affected are those with higher fat concentrations: breast, abdomen, thighs, hips.
  • Secondary infection VERY common

Diagnosis:

  • Often made clinically, though histopathology is considered the gold standard.
    • Medial calcification of small arteries and arterioles with intimal hyperplasia, inflammation, endovascular fibrosis, thrombosis and tissue necrosis. Panniculitis can also be present.
  • However, biopsy does raise concern for initiating a new ulcer that may not heal!
    • Take home: biopsy when clinical picture is not clear in order to rule out other diagnoses such as warfarin-induced skin necrosis, vasculitis, cholesterol embolism syndrome, nephrogenic systemic fibrosis
  • Other diagnostic modalities include:
    • Bone scintography – sensitivity of 97% in detecting abnormal calcifications

Treatment (from the 2014 review by Yerram and Chaudhary linked above):

capture.png

Evernote: https://www.evernote.com/shard/s462/sh/f713400a-0cb6-40ff-8364-d38d25920a33/1892f0305deba2091a3a0370c9f5be38

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s