The patient had a significant medical history, including nonischemic cardiomyopathy due to hypertension and polysubstance use.
By: Mariana Mestizo Hernandez
December 26, 2023
The medical literature describes the case of a 51-year-old woman who presented to the hospital with complaints of lower extremity pain and a skin rash that had progressed over the past month.
Significant background
The patient had a significant medical history, including nonischemic cardiomyopathy due to hypertension and polysubstance use, congestive heart failure with a reduced ejection fraction of 30-35%, complicated by a left ventricular apical thrombus and multiple cardioembolic infarcts, deep vein thrombosis, peripheral vascular disease and cellulitis due to methicillin-resistant Staphylococcus aureus.
The patient’s current medications included carvedilol, furosemide, hydroxyzine, losartan, spironolactone, and warfarin, the latter started one month before presentation to treat left ventricular apical thrombus. Despite this complicated medical history, the patient was vitally stable at the time of presentation.
Physical exploration
On physical examination, a well-defined, violaceous, nonpruritic skin rash was identified located on the bilateral lower extremities. Given the high suspicion of a drug-induced skin rash, treatment was discontinued. Warfarin and subcutaneous low molecular weight heparin (LMWH) were started as an alternative anticoagulant.
Laboratory results revealed relevant findings, and ultrasound ruled out deep vein thrombosis in the lower extremities. A skin biopsy confirmed the presence of a small vessel cutaneous leukocytoclastic vasculitis urticarial subtype, with a predominant perivascular neutrophilic inflammatory infiltrate.
Medical evolution
The rash began to improve two days after discontinuation of the warfarin and it almost completely resolved on the fourth day, without the need to start corticosteroids. Six weeks after hospitalization, the patient had complete resolution of the rash without recurrences or additional thromboembolic events.
Given the diagnosis of small vessel cutaneous leukocytoclastic vasculitis induced by warfarin, it was decided not to resume this treatment. However, due to persistent left ventricular apical thrombus, anticoagulation was considered necessary. Despite the patient’s fear of needles, she was administered apixaban as an alternative to LMWH, with a good clinical response and no significant adverse events during follow-up.
Small vessel cutaneous leukocytoclastic vasculitis
The small vessel cutaneous leukocytoclastic vasculitis is a rare complication associated with treatment with warfarin, according to the diagnostic criteria of the American College of Rheumatology. These criteria include palpable purpura, maculopapular rash, and histopathological confirmation by biopsy.
The small vessel cutaneous leukocytoclastic vasculitis induced by warfarin initially manifests as asymptomatic hemorrhages that evolve into palpable purpura, mainly in dependent areas of the body. The time of appearance varies between one and three weeks from the start of treatment with warfarin.
Therapeutic management involves the suspension of the offending drug and the addition of anti-inflammatories, antihistamines, corticosteroids, or immunosuppressants, depending on the severity. However, the complication arises in patients with concomitant conditions that require continued use of warfarin.
Skin necrosis induced by warfarin, another rare side effect, differs from small vessel cutaneous leukocytoclastic vasculitis due to its early appearance and histopathological characteristics. Prompt identification is essential for adequate treatment.
Warfarin Risks
Although the warfarin is the preferred agent in patients with LV thrombus, those with small vessel cutaneous leukocytoclastic vasculitis high thromboembolic risk pose a challenge. Studies suggest that direct-acting anticoagulants (DOACs) may be an effective alternative, reducing the risk of stroke and bleeding.
The American Heart Association, in its 2022 update, supports the use of DOACs as a reasonable option for warfarin in patients with LV thrombus after myocardial infarction and cardiomyopathies. This approach may improve symptomatology in patients with small vessel cutaneous leukocytoclastic vasculitis and comorbidities that limit the use of warfarin.
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