Tumor lysis syndrome (TLS) is a metabolic disorder caused by massive tumor lysis. Hypouricemic agents are administered to prevent TLS-related hyperuricemia and renal failure. We experienced three cases of urine xanthine crystals during TLS in patients with hematologic malignancies who received prophylactic febuxostat. ⋯ Urine microscopy revealed that the deposits were xanthine crystals. In rapid tumor lysis, inhibition of xanthine oxidase can cause xanthine accumulation and urine xanthine crystallization. During TLS, urine xanthine crystals may be overlooked, so careful observation and management are required to avoid xanthine nephropathy.
Shoko Ito, Shin-Ichiro Fujiwara, Tomoaki Yoshizawa, Kaori Hayatsu, Kaoru Sekiguchi, Rui Murahashi, Hirotomo Nakashima, Sae Matsuoka, Takashi Ikeda, Yumiko Toda, Shinichiro Kawaguchi, Takashi Nagayama, Kent... more o Umino, Daisuke Minakata, Hirofumi Nakano, Kaoru Morita, Ryoko Yamasaki, Masahiro Ashizawa, Chihiro Yamamoto, Kaoru Hatano, Kazuya Sato, Ken Ohmine, and Yoshinobu Kanda. less
Division of Hematology, Department of Medicine, Jichi Medical University, Japan.
Intern. Med. 2022 Nov 1; 61 (21): 327132753271-3275.
AbstractTumor lysis syndrome (TLS) is a metabolic disorder caused by massive tumor lysis. Hypouricemic agents are administered to prevent TLS-related hyperuricemia and renal failure. We experienced three cases of urine xanthine crystals during TLS in patients with hematologic malignancies who received prophylactic febuxostat. Yellowish and pinkish deposits were observed in urinary tract catheters and urinary bags. Urine microscopy revealed that the deposits were xanthine crystals. In rapid tumor lysis, inhibition of xanthine oxidase can cause xanthine accumulation and urine xanthine crystallization. During TLS, urine xanthine crystals may be overlooked, so careful observation and management are required to avoid xanthine nephropathy.