Abstract: SA-PO198
Calcific Uremic Arteriolopathy (CUA) Mimicking Infectious Cellulitis
Session Information
- Vascular Calcification, Nephrolithiasis, Bone
November 05, 2022 | Location: Exhibit Hall, Orange County Convention Center‚ West Building
Abstract Time: 10:00 AM - 12:00 PM
Category: Bone and Mineral Metabolism
- 402 Bone and Mineral Metabolism: Clinical
Authors
- Awad, Mina, Albany Medical Center, Albany, New York, United States
- Gosmanova, Elvira O., Albany Medical Center, Albany, New York, United States
Introduction
CUA is caused by dermis and subcutaneous fat small vessel calcifications leading to skin ischemia and necrosis. CUA is mainly observed in patients with ESKD. CUA usually presents with intensely painful skin nodules or lesions with characteristic purple net-like patterns in areas with high fat content. In this case, the initial presentation of CUA was a diffuse right lower extremity (RLE) erythema and severe pain that were misdiagnosed as infectious cellulitis.
Case Description
A 57-yo male with ESKD on HD developed progressively worsening RLE pain and redness. On exam, RLE was diffusely tender, swollen and erythematous but without skin breaks. There were no associated fever, leukocytosis or DVT. After 10 days of intravenous (IV) vancomycin for the diagnosis of infctious cellulitis, there was no improvement (Fig1a). X-ray of RLE (done to exclude fracture) showed prominent vascular calcifications. Therefore, diagnosis of CUA was suspected. After skin biopsy, empiric treatment with IV sodium thiosulfate 25grams after each HD was started with marked improvement in RLE pain within 1 week. A punch biopsy of RLE skin showed no signs of CUA; however, characteristic stellate lesion for CUA developed at the biopsy site (Fig1b). Patient’s CUA risk factors included ESKD with high fluid gains, diabetes, uncontrolled hyperphosphatemia, treated with lanthanum (previously was on Ca acetate), secondary hyperparathyroidism (PTH>1000pg/ml) on etelcacetide and paricalcitol.
Discussion
It is critical to know unusual presentations of CUA, such as CUA presenting with diffuse skin erythema resembling cellulitis rather than patchy retiform purpura with ulcerative lesions. Misdiagnosis may lead to inappropriate antibiotic use and a delay in CUA treatment. Constellation of severe pain and arterial calcifications in the affected area on x-ray were clues for the diagnosis of CUA. Skin biopsy may lead to skin ulceration and be unrevealing in 50% of cases. We advocate to avoid skin biopsy when clinical suspicion for CUA is high.
Figure1: Skin changes in the right leg before (a) and after (b) skin biopsy.