title: Acute kidney injury induced by thrombotic microangiopathy in a patient with hemophagocytic lymphohistiocytosis.
abstract: BACKGROUND
  Hemophagocytic lymphohistiocytosis (HLH) is a fatal clinical syndrome characterized by excessive immune activation and inflammation. It is frequently complicated by acute kidney injury (AKI) that often develops as acute tubular necrosis (ATN). Meanwhile, renal thrombotic microangiopathy (TMA) is a rare pathologic finding that mostly occurs in hemolytic uremic syndrome or thrombotic thrombocytopenic purpura. There are only few reports on TMA developing in patients with HLH. We present here a rare case of TMA associated HLH.
  
  
  METHODS
  A 60-year-old woman was admitted for a fever of unknown origin that had persisted for several weeks. She presented with AKI and pancytopenia. Clinical, laboratory and bone marrow biopsy findings met the criteria of HLH. Kidney biopsy showed TMA and minimal ATN, which suggested that the primary cause of AKI was TMA in this case. Because of sustained oliguria, we initiated hemodialysis (HD) and also decided to use chemotherapy composed of dexamethasone, etoposide and cyclosporine for treatment of HLH. Six months after the initiation of chemotherapy, pancytopenia was completely resolved, indicating the resolution of HLH. At the same time, serum creatinine decreased to a normal range without the need for HD, suggesting the resolution of TMA.
  
  
  CONCLUSIONS
  We report a case of renal TMA associated HLH. This case suggests that renal TMA should be considered as a primary cause of AKI in patients with underlying HLH.
authors.affiliation: Division of Nephrology, Department of Internal Medicine, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, 222 Banpodae-ro, Seocho-gu, Seoul, 137-040, Korea.
authors.forename: Myoung Nam
authors.initials: MN
authors.lastname: Bae
authors.affiliation: Division of Nephrology, Department of Internal Medicine, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, 222 Banpodae-ro, Seocho-gu, Seoul, 137-040, Korea.
authors.forename: Dae Hun
authors.initials: DH
authors.lastname: Kwak
authors.affiliation: Division of Nephrology, Department of Internal Medicine, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, 222 Banpodae-ro, Seocho-gu, Seoul, 137-040, Korea.
authors.forename: Se Jun
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Division of Nephrology, Department of Internal Medicine, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, 222 Banpodae-ro, Seocho-gu, Seoul, 137-040, Korea.
authors.forename: Bum Soon
authors.initials: BS
authors.lastname: Choi
authors.affiliation: Division of Nephrology, Department of Internal Medicine, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, 222 Banpodae-ro, Seocho-gu, Seoul, 137-040, Korea.
authors.forename: Cheol Whee
authors.initials: CW
authors.lastname: Park
authors.affiliation: Department of Hospital Pathology, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, 222 Banpodae-ro, Seocho-gu, Seoul, 137-040, Korea.
authors.forename: Yeong Jin
authors.initials: YJ
authors.lastname: Choi
authors.affiliation: Division of Hematology, Department of Internal Medicine, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, 222 Banpodae-ro, Seocho-gu, Seoul, 137-040, Korea.
authors.forename: Jong Wook
authors.initials: JW
authors.lastname: Lee
authors.affiliation: Division of Nephrology, Department of Internal Medicine, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, 222 Banpodae-ro, Seocho-gu, Seoul, 137-040, Korea.
authors.forename: Chul Woo
authors.initials: CW
authors.lastname: Yang
authors.affiliation: Division of Nephrology, Department of Internal Medicine, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, 222 Banpodae-ro, Seocho-gu, Seoul, 137-040, Korea.
authors.forename: Yong-Soo
authors.initials: YS
authors.lastname: Kim
authors.affiliation: Division of Nephrology, Department of Internal Medicine, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, 222 Banpodae-ro, Seocho-gu, Seoul, 137-040, Korea. Chungbh@catholic.ac.krAQ2.|Department of Internal Medicine, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, 222 Banpodae-ro, Seocho-gu, Seoul, 137-040, Korea. Chungbh@catholic.ac.krAQ2.
authors.forename: Byung Ha
authors.initials: BH
authors.lastname: Chung
mesh_terms: D058186:Acute Kidney Injury / Q000209:etiology*; D005260:Female; D006801:Humans; D007684:Kidney Tubules / Q000473:pathology*; D051359:Lymphohistiocytosis, Hemophagocytic / Q000150:complications*; D008875:Middle Aged; D009336:Necrosis / Q000209:etiology; D057049:Thrombotic Microangiopathies / Q000150:complications*