Ultrasound-guided core-needle biopsy for the diagnosis of calciphylaxis in a peritoneal dialysis patient

Calciphylaxis is a life-threatening and rare disease, also known as calcific uremic arteriolopathy (CUA). Skin biopsy is the gold standard for diagnosis. However, it is an invasive procedure and might aggravate the ulcer. Therefore, additional precise diagnostic approaches are needed. In this case report, a patient with end-stage renal disease receiving peritoneal dialysis presented with skin ulceration and necrosis on the left leg. Considering the risk of aggravating the existing ulcer, we performed an ultrasound-guided core-needle biopsy. Histopathological examination confirmed calcification of small- and medium-sized vessels in the dermis and subcutaneous tissue, supporting the diagnosis of calciphylaxis. The patient subsequently received comprehensive treatment, including sodium thiosulfate therapy, wound care, correction of chronic kidney disease-mineral and bone disorder, and adjustment of dialysis therapy. With comprehensive and timely treatment, the patient's skin lesions gradually improved and showed progressive healing. This case suggests that ultrasound-guided core-needle biopsy may represent a feasible diagnostic option for calciphylaxis, providing histopathological confirmation.