A 35-year-old man with systemic lupus erythematosus presents with hematuria and dysuria. Vital signs show BP 145/92 mmHg, HR 88/min, RR 16/min, temperature 37.2°C, SpO2 98%. Urinalysis reveals pyuria, cellular casts, and 2 g/day proteinuria. Serum creatinine is 1.4 mg/dL. Kidney biopsy demonstrates endocapillary proliferation with wire-loop lesions and subendothelial immune deposits. C3 and C4 are markedly reduced. Complement-fixing antibody titers are elevated. No pulmonary hemorrhage noted. Which lupus nephritis class does this represent?
- A)Class I (minimal mesangial)
- B)Class IV (diffuse proliferative)GABARITO
- C)Class V (membranous)
- D)Class III (focal proliferative)
- E)Class II (mesangial proliferative)
Explicação
Wire-loop lesions (subendothelial immune deposits) with diffuse endocapillary proliferation characterize Class IV lupus nephritis—the most aggressive form. Markedly low C3/C4 reflects severe immune complex deposition. Presentation includes active urinary sedim... Ver explicação completa e trilha adaptativa →