A rare complication of IgA vasculitis: renal and intestinal ischemia successfully treated with plasmapheresis.

BACKGROUND: IgA vasculitis (IgAV) is a multisystemic small vessel vasculitis and is the most common vasculitis in childhood. The characteristic findings of IgAV are palpable purpuric rash, abdominal pain, arthralgia or arthritis, and hematuria. Ischemic complications are very rare in IgAV. Thrombotic complications can be observed after a COVID-19 infection. Also in the presence of familial Mediterranean fever, IgAV may have an atypical or more severe course. CASE: We present a case of IgAV complicated with renal infarction and intestinal ischemia. There was no recent or distant history of COVID-19 in the patient or family members, but the patient`s COVID-19 antibody was positive. In addition, MEFV gene analysis of the patient showed homozygous M694V mutation. The patient did not respond to enoxaparin, pulse methylprednisolone, intravenous immunoglobulin (IVIG), iloprost, and cyclophosphamide treatments. She was successfully treated with six sessions of plasmapheresis. CONCLUSIONS: Plasmapheresis seems to be an effective treatment option in IgAV-related ischemic findings that do not respond to intensive immunosuppressive therapy.

A pediatric case of Takayasu's arteritis with anti-neutrophil cytoplasmic antibody-associated vasculitis triggered by COVID-19 infection.

Takayasu's arteritis (TA) is a rare chronic granulomatous vasculitis characterized by large-vessel involvement. The aorta and its main branches are most commonly involved. Although pulmonary artery involvement is common, hemoptysis or respiratory findings are rarely seen. Herein, we present a case of TA who developed anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis with diffuse alveolar hemorrhage after coronavirus disease 2019 (COVID-19) infection. A 17-year-old female patient with the diagnosis of TA presented with cough, bloody vomiting, and diarrhea. In follow-up, she developed tachypnea and dyspnea and was transferred to the pediatric intensive care unit. The findings on the chest computed tomography were compatible with acute COVID-19 infection, but the SARS-CoV2 reverse transcription-polymerase chain reaction test was negative, but SARS-CoV2 immunoglobulin (Ig) G and IgM antibody tests were positive. The patient was not vaccinated against COVID-19. The bronchoscopy showed bronchial mucosal fragility, bleeding foci, and mucosal bleeding. The broncoalveolar lavage hemosiderin-laden macrophages were seen in the histopathologic examination. The indirect immunofluorescence assay-ANCA test became 3 (+) with myeloperoxidase (MPO)-ANCA of 125 RU/ml (normal: <20). Cyclophosphamide and pulse steroid treatment were started. After immunosuppressive therapy, the patient condition improved and did not have hemoptysis again. The successful response was obtained by applying balloon angioplasty to the patient with bilateral renal artery stenosis. Types of post-COVID vasculitis include thromboembolic events, cutaneous vasculitis, Kawasaki-like vasculitis, myopericarditis, and ANCA-associated vasculitis. It is thought that COVID-19 may impair immune tolerance and trigger autoimmunity with cross-reaction. To the best of our knowledge, the third pediatric case was reported with MPO-ANCA-positive COVID-associated ANCA vasculitis.