Deep vein thrombosis: An unusual way of revealing microscopic polyangiitis. Deep vein thrombosis in microscopic polyangiitis

Abstract

Unexplained deep vein thrombosis may justify screening for antineutrophil cytoplasmic antibody‐associated vasculitis as it can be an unusual presentation of this disease.

Propylthiouracil-Induced Anti-Neutrophil Cytoplasmic Antibody (ANCA)-Associated Vasculitis Presenting with Multiple Sterile Abscesses, Mononeuritis Multiplex, and Splenic Vein Thrombosis: A Case Report and Literature Review

“…Some case reports describe AAV presenting with venous thromboembolism (VTE) [ 17 ], and one case report described cerebral vasculitis as a manifestation of the disease [ 13 ]. Even though ANCA autoantibodies are implicated in primary AAV, different mechanisms likely contribute to PTU-induced AAV [ 2 ].…”

“…The most affected systems in AAV include renal, pulmonary, and skin [ 6 , 7 , 15 , 16 ], with common symptoms being hematuria, proteinuria, hemoptysis, dyspnea, ulcers, purpura, and rash [ 7 ]. Less common symptoms include joint swelling, uveitis, abdominal pain, and multiple cranial nerve deficits [ 7 ], with VTE also reported [ 17 ]. Cutaneous manifestations can vary widely, with sterile pustules/abscesses being less common [ 16 ].…”

“…Studies indicate that in active AAV, NET formation is abundant and closely associated with thrombi, suggesting that NETs are significant drivers of hypercoagulability through activation of both intrinsic and extrinsic pathways [ 15 , 19 ]. AAV-related VTE is treated with standard anticoagulation therapies [ 17 ], and common VTE sites include deep veins, pulmonary embolism, and rare splanchnic thromboses [ 17 ].…”

“…Diagnosis of PTU-induced AAV typically involves histologic evidence of vasculitis, serum ANCA presence, and exposure to a causative drug like PTU. Common diagnostic specimens include renal or skin biopsies, with bronchoscopy used to detect diffuse alveolar hemorrhage [ 9 , 17 ]. In our case, a sural nerve biopsy confirmed vasculitis as skin biopsies were inconclusive, and renal involvement was mild at presentation.…”