title: [Analysis of L-asparaginase induced elevation of blood ammonia and hepatic encephalopathy].
abstract: OBJECTIVE
  To summarize the incidence of various adverse reactions in the clinical application of L-asparaginase (L-Asp), and to analyze the cause of hepatic encephalopathy in three cases.
  
  
  METHODS
  The complete data of 23 patients in our department from December 2009 to December 2010 were collected. Their blood ammonia levels, transaminase, serum albumin and blood coagulation function before, during and after the L-Asp application were assayed.
  
  
  RESULTS
  (1) All patients had elevated blood ammonia level after the L- Asp application. This occurred 2 days after the beginning of treatment and the median time to reach peak level (ranged from 194 to 446 μmol/L, with a median value of 300 μmol/L) was 4 days. It returned to normal level after a median time of 5 days (ranged 3-7 days) with drug withdrawal. Of the 23 patients studied, 3 developed hepatic encephalopathy. (2) All patients appeared lower blood fibrinogen, 10 cases (43.5%) with lower fibrinogen only, while 13 cases (56.5%) with both prolonged APTT and lower fibrinogen. The lowest level of fibrinogen was detected at 1 week after drug application. Of the 23 patients, 14 (60.9%) had mild lower blood fibrinogen (1-2 g/L), and 9 (39.1%) had significantly lower fibrinogen (0-1 g/L). (3) Six cases (26.1%) had slightly elevated level of transaminase (<2 times the upper limits of normal), 8 (34.8%) appeared hypoalbuminemia.
  
  
  CONCLUSIONS
  As the incidence of elevated blood ammonia levels was high in the application of L-Asp, the level of blood ammonia should be closely monitored to avoid the occurrence of hepatic encephalopathy, especially in elderly patients and patients with previous liver disease or long-term heavy drinking. L-Asp can also lead to low fibrinogen level, hypoalbuminemia and abnormal transaminase. Monitoring the blood coagulation function and liver function is required and, if necessary, plasma infusion and liver protection therapy are required.
authors.affiliation: Department of Hematology, Peking University First Hospital, Beijing 100034, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Li
authors.forename: Han-yun
authors.initials: HY
authors.lastname: Ren
authors.forename: Xi-nan
authors.initials: XN
authors.lastname: Cen
authors.forename: Yue
authors.initials: Y
authors.lastname: Yin
authors.forename: Ze-yin
authors.initials: ZY
authors.lastname: Liang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000641:Ammonia / Q000097:blood*; D001215:Asparaginase / Q000009:adverse effects* / Q000627:therapeutic use; D005260:Female; D006501:Hepatic Encephalopathy / Q000139:chemically induced*; D006801:Humans; D008297:Male; D008875:Middle Aged; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000097:blood* / Q000188:drug therapy; D055815:Young Adult
chemical_list: D000641:Ammonia; D001215:Asparaginase