From the Guidelines
Levamisole-associated vasculitis is primarily caused by the immunomodulatory effects of levamisole, leading to immune complex formation, antibody induction, and direct endothelial damage, as noted in the 2023 study by Beck Jr et al 1. The mechanism of levamisole-associated vasculitis involves:
- Immune complex formation and deposition in blood vessel walls, triggering inflammation and vessel damage
- Induction of antibody formation, particularly antineutrophil cytoplasmic antibodies (ANCA) and antiphospholipid antibodies
- Enhancement of neutrophil chemotaxis and adhesion
- Direct damage to endothelial cells lining blood vessels
- Induction of antibodies against neutrophils, leading to neutropenia
- Potential triggering of autoimmunity by altering self-antigens This combination of immune dysregulation and direct toxicity leads to the characteristic clinical presentation of purpuric skin lesions, particularly on the ears and extremities, along with systemic symptoms, as discussed in the context of ANCA-associated vasculitis management 1. The primary treatment involves cessation of cocaine use, as the vasculitis typically resolves within weeks to months after removing the exposure, though immunosuppressive therapy may be needed in severe cases, in line with recommendations for managing ANCA-associated vasculitis 1.
From the Research
Mechanism of Levamisole-Associated Vasculitis
The mechanism of levamisole-associated vasculitis is not fully understood, but several studies have shed light on its characteristics and effects on the body.
- Levamisole, an immunomodulator and anthelmintic medication, has been linked to severe adverse events such as vasculitis and neutropenia 2.
- The use of levamisole-adulterated cocaine has been associated with a characteristic cutaneous vasculitis syndrome, presenting with painful, purpuric rash in a retiform or stellate pattern 3.
- Histologic features of levamisole-induced vasculitis include microvascular thrombi and/or leukocytoclastic vasculitis involving small vessels of the superficial and deep dermis 3.
- Laboratory findings may include leukopenia, neutropenia, elevated erythrocyte sedimentation rate, and positive autoantibodies such as perinuclear and cytoplasmic antineutrophil cytoplasmic antibodies 3.
Clinical Presentation and Diagnosis
- Patients with levamisole-induced vasculitis typically present with a painful, purpuric rash, often with central necrosis, involving the extremities, trunk, nasal tip, digits, cheeks, and/or ears 3, 4.
- A history of cocaine abuse is often elicited, and lesions typically resolve with the cessation of cocaine use 3.
- Diagnosis requires a multidisciplinary team approach, as no standardized diagnostic or treatment algorithm exists for this condition 5.
- Early identification of levamisole-induced ulcers is crucial for favorable treatment outcomes, and a complete medical and social history is necessary for physicians to treat these lesions with local wound care and provide therapy for patients with addictions 6.