title: Clinical utility of ammonia concentration as a diagnostic test in monitoring of the treatment with L-asparaginase in children with acute lymphoblastic leukemia.
abstract: L-asparaginase (ASP) is an enzyme used as one of the basic regimens in the acute lymphoblastic leukemia (ALL) therapy. Because of the possibility of the enzyme inactivation by antibodies, monitoring of ASP activity is essential. The aim of the study was to examine if plasma concentration of ammonia, a direct product of the reaction catalyzed by ASP, can be used in the assessment of ASP activity. A group of 87 patients with acute lymphoblastic leukemia treated in the Department of Pediatric Oncology and Hematology in Krakow was enrolled to the study. ASP activity and ammonia concentration were measured after ASP administrations during induction. A positive correlation was found between the ammonia concentration and ASP activity (R = 0.44; P < 0.0001) and between the medium values of ammonia concentration and ASP activity (R = 0.56; P < 0.0001). The analysis of ROC curves revealed the moderate accuracy of the ammonia concentration values in the ASP activity assessment. It was also found that the medium value of ammonia concentrations can be useful in identification of the patients with low (<100 IU/L) and undetectable (<30 IU/L) ASP activity. The plasma ammonia concentration may reflect ASP activity and can be useful when a direct measurement of the activity is unavailable.
authors.affiliation: Department of Pediatric Oncology and Hematology, Children's University Hospital, ul. Wielicka 265, 30-663 Krakow, Poland.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Czogała
authors.affiliation: Department of Pediatric Oncology and Hematology, Children's University Hospital, ul. Wielicka 265, 30-663 Krakow, Poland ; Department of Pediatric Oncology and Hematology, Polish American Institute of Pediatrics, Jagiellonian University Medical College, ul. Wielicka 265, 30-663 Krakow, Poland.
authors.forename: Walentyna
authors.initials: W
authors.lastname: Balwierz
authors.affiliation: Department of Clinical Biochemistry, Polish American Institute of Pediatrics, Jagiellonian University Medical College, ul. Wielicka 265, 30-663 Krakow, Poland.
authors.forename: Krystyna
authors.initials: K
authors.lastname: Sztefko
authors.affiliation: Department of Clinical Biochemistry, Polish American Institute of Pediatrics, Jagiellonian University Medical College, ul. Wielicka 265, 30-663 Krakow, Poland.
authors.forename: Iwona
authors.initials: I
authors.lastname: Rogatko
mesh_terms: D000293:Adolescent; D000641:Ammonia / Q000097:blood*; D001215:Asparaginase / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D003955:Diagnostic Tests, Routine / Q000379:methods*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008991:Monitoring, Physiologic; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000097:blood / Q000175:diagnosis* / Q000188:drug therapy*; D012372:ROC Curve
chemical_list: D000641:Ammonia; D001215:Asparaginase