Abstract
Systemic vasculitis associated with antineutrophil cytoplasmic antibodies (ANCA) are rare but clinically significant disorders characterized by polymorphic symptoms and often diagnosed at the stage of irreversible organ damage. Early diagnosis largely depends on the vigilance of the internist, who is the first to encounter nonspecific manifestations. The article discusses the clinical case of a 54-year-old male patient presented to an internist with complaints of prolonged low-grade fever, weight loss, arthralgia, weakness, paresthesia in the feet, and newly diagnosed arterial hypertension. The internist, considering the combination of symptoms, ordered a urinalysis and blood biochemistry, which revealed active nephritic sediment (hematuria, proteinuria, cylindruria) and elevated creatinine to 142 µmol/L (eGFR 48 mL/min/1.73 m2), indicating rapidly progressive glomerulonephritis. The patient was urgently referred to a nephrologist with suspected systemic vasculitis. Immunological testing confirmed high-titer anti-myeloperoxidase antibodies, and kidney biopsy revealed pauci-immune necrotizing glomerulonephritis with crescents. A diagnosis of microscopic polyangiitis with renal, pulmonary, and peripheral nervous system involvement was made. Induction immunosuppressive therapy (glucocorticoids, cyclophosphamide, plasmapheresis) was initiated, leading to stabilization of renal function and clinical and laboratory remission. This case highlights the pivotal role of the internist in the early diagnosis of systemic vasculitis. Systemic clinical thinking, correct interpretation of routine tests (urinalysis, creatinine), and timely patient referral prevented irreversible kidney damage. The internist acts not only as the first point of contact but also as the coordinator of multidisciplinary management for patients with systemic diseases.
Keywords: microscopic polyangiitis, systemic vasculitis, ANCA-associated vasculitis, rapidly progressive glomerulonephritis, multiple mononeuritis, therapist, differential diagnosis, systemic disease.
For citation:Ametova L.O., Dolya E.M., Alpan A.E., Abdurazakova E.E., Yakubov A.S., Shumilina N.I., Seydametova M.A., Alieva M.A. Systemic vasculitis involving the kidneys, lungs, and peripheral nervous system: a clinical case of microscopic polyangiitis, diagnosed by a therapist during analysis of non-specific symptoms. Clinical review for general practice. 2026; 7 (6): 74–78 (In Russ.). DOI: 10.47407/kr2026.7.6.00866
All accepted articles publish licensed under a Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) which allows users to read, copy, distribute and make derivative works for non-commercial purposes from the material, as long as the author of the original work is cited properly.
