Diagnosis and treatment of systemic vasculitis: Case report and literature review

Systemic vasculitis is one of the most challenging, complex and difficult diseases in the field of rheumatic diseases and even in the field of internal medicine, which can involve multiple systems of the whole body. Owing to their rich vascular beds, the lungs and kidneys are among the most commonly affected organs in systemic vasculitis. Lung involvement can manifest as interstitial lung disease, diffuse alveolar hemorrhage, pulmonary nodules, pulmonary arterial hypertension, pulmonary aneurysms, pulmonary arteriovenous thrombosis, etc, which are easily confused with infections, tumors, and other diseases. Renal involvement in systemic vasculitis presents with a diverse spectrum of clinical manifestations. Given its high prevalence, complex clinical presentation, significant diagnostic challenges, and generally poor prognosis, achieving a thorough understanding of its various phenotypes, establishing an early diagnosis, and initiating prompt and aggressive treatment are crucial for substantially improving patient outcomes.

A 68-year-old man presented with a cough. His condition deteriorated despite antibiotic treatment for suspected pneumonia, followed by the development of worsening renal function evidenced by progressively elevated serum creatinine and proteinuria. Subsequent serological testing was positive for antineutrophil cytoplasmic antibody antibodies.

Laboratory tests and pulmonary computed tomography scan.

The patient was started on a regimen of oral cyclophosphamide and high-dose glucocorticoids.

The patient's renal function has deteriorated and requires maintenance hemodialysis.

This case emphasizes the necessity of maintaining vigilance when distinguishing ANCA-associated vasculitis lung damage from lung infection in patients.