Warfarin (Coumadin)-Induced Skin Necrosis

51 yo AAF was admitted to the hospital with CC: SOB x 1 week and and pain in the right thigh x 3 weeks. The SOB was not getting better with the aerosol treatment. She also complained of occasional orthopnea and PND. Right thigh pain started 3 weeks ago, in the medial part of the right thigh, throbbing in nature, associated with redness. Patient complained of swelling in the same region which had progressed over the the past few days. Denied fever or chills.

PMH:
Asthma, CHF, DM, anemia, pancreatitis, HTN, shingles

PSH:
Cholecystectomy, thyroidectomy

Medications:
Prednisone, Lasix, Synthroid, Norvasc, K-Dur, Diovan, Percocet, aerosols, Advair, Singulair, Flonase, Nexium, Neurontin

FH:
DM, HTN

Physical examination:
Obese lady in NAD
VS 36.7- 88-18-176/95 SpO2 95% on RA
Chest: (B) wheezing
Heart: Clear S1S2
Abd: Obese, NT, +BS
Ext: (B) 3+ edema, right thigh was swollen, erythematous and tender. Peripheral blood vessels could not be felt in the lower extremities because of the edema.

What happened?
BNPep was 10, and D-dimer was 7000
Duplex of LE showed a RLE DVT.

She was admitted for asthma exacerbation and DVT in her right extremity. Patient was started on heparin IV and then later on switched to Lovenox. Coumadin was started within 48 hours.


CBC, BMP, INR; Anticoagulant treatment time frame

What happened next?
Two days after starting Coumadin, the patient developed ecchymoses over her lower abdomen and upper extremities. Small black eschars appeared in the center of some of the ecchymoses with a "halo" around the lesions. These skin lesions were completely asymptomatic - no pain or itching.
Coumadin-induced skin necrosis was diagnosed and Coumadin was stopped. Lovenox 1 mg/kg SQ QD was continued for 2 days, then IVC filter was placed and Lovenox was stopped. She did not have any new lesions.


Coumadin-induced skin necrosis

Final diagnosis:
Coumadin-induced skin necrosis

What did we learn from this case?
Coumadin-induced skin necrosis can occur in DVT patients when oral anticoagulation is started, despite the heparin coverage.
The classic large necrotic areas seen in the textbooks occur in patients treated with Coumadin only (without heparin). In real life, when heparin us used, the skin necrosis areas are often much smaller in size, like in our patient.

References:
Dermatologic Manifestations of Hematologic Disease. eMedicine.
Coumadin Skin Necrosis. Boston University.
Coumadin-Induced Skin Necrosis. Medscape, 11/12/2002.
Heparin-Induced Skin Necrosis - NEJM Volume 335:715, September 5, 1996, Number 10