Patterns of renal pathology in Chinese patients with systemic sclerosis undergoing renal biopsy at a tertiary medical center

OBJECTIVE: We investigated renal injury characteristics in Chinese patients with systemic sclerosis (SSc) who had undergone renal biopsy. METHODS: We searched the medical records of patients with SSc who were hospitalized at Peking Union Medical College Hospital between January 1990 and August 2019. We analyzed the clinical characteristics and pathological results of these patients. RESULTS: We identified 25 patients who had undergone renal biopsy. Of these patients, 10 had scleroderma renal crisis (SRC); one underwent renal biopsy twice (for diffuse mesangial proliferative glomerulonephritis and for SRC); two had antineutrophil cytoplasmic antibody-associated glomerulonephritis; one had immunoglobulin M nephropathy; one had minimal change nephropathy; seven had lupus nephritis; one had scleroderma renal crisis with comorbid lupus nephritis; and two had drug-related kidney injury (caused by aristolochic acid in one and D-penicillamine in the other). Acute tubular necrosis was observed in the patient taking oral aristolochic acid, while minimal change nephropathy was observed in the patient with D-penicillamine-induced renal injury. CONCLUSIONS: SRC was the most commonly encountered renal damage in patients with SSc. We recommend biopsy for patients undergoing treatment for SRC who have persistent renal injury with proteinuria, regardless of hematuria. Rheumatologists in Eastern countries should be aware of aristolochic acid nephropathy.