A case report: Necrotising leukocytoclastic vasculitis (NLV) of the breast mimicking necrotising fasciitis (NF)

ABSTRACT

Leukocytoclastic vasculitis (LV) is an inflammation of the small vessels in the dermis characterised by the deposition of immunocomplexes in the involved vessel walls. It commonly manifests as palpable purpura, limited to the skin and predominantly of the lower limb. We report a rare case of necrotising LV (NLV) affecting bilateral breast, manifesting clinical features of necrotising fasciitis (NF), and emphasizes the potential diagnostic challenges that markedly influence the treatment and survival of patients. A 48-year-old female presented with an acute onset left breast skin necrosis and discolouration that rapidly progressed to the contralateral breast with surrounding erythema and oedema of the chest wall yet spared the intermammary cleft. Some non-blanching purpuric rash were also noted on upper abdomen and left lower limb. COVID-19 test was negative. CT scan showed extensive bilateral breast fat stranding and oedema. Patient became clinically septic with a moderately raised CRP and mild acute kidney injury. Radical mastectomies and chest wall excision were performed with intra-operative findings of cloudy fluid and easily peeled away subcutaneous tissue from fascia. Urgent gram stain and culture showed no organisms. Tissue biopsies subsequently showed the diagnosis of NLV. Chest wall defect was then reconstructed with split skin grafts, NLV treated with corticosteroids and patient made an uneventful recovery. This case highlights the incidence of a rare and aggressive manifestation of NLV on the breast that mimics NF, emphasizing the clinical differentiation that may lead to catastrophic results and significant cosmetic defect, if a differential diagnosis cannot be determined at the time.