Korean J Clin Pathol.  1999 Apr;19(2):181-189.

Clinical Utility of Adenosine Deaminase Isoenzyme Determinations in Leukemia

• Shin DH
• Cho HC
• Kang SH
• Park IG
• Yoon KJ

Abstract

BACKGROUND
Adenosine deaminase (ADA), an enzyme involved in purine metabolism, catalyzes the hydrolytic deamination of adenosine or 2-deoxyadenosine to inosine or 2-deoxyinosine. Human ADA consists of three molecular forms: ADA1, ADA1+CP, and ADA2. The two ADA isoenzymes represent two different gene products and have different tissue distributions, and their concentrations in serum appear to reflect different pathological conditions or physiological responses. Elevation of serum ADA activity has been described especially in leukemia and lymphoma. The purpose of this study was to evaluate the clinical utility of ADA isoenzyme determination in the diagnosis of leukemia.
METHODS
We studied the activity of serum ADA and its isoenzyme in 44 leukemic patients. The study population consisted of 17 patients with acute lymphoblastic leukemia (ALL), 23 with acute myeloid leukemia (AML), and 4 with chronic myelogenous leukemia (CML). ADA isoenzyme was measured by erythro-9- (2-hydroxy-3-nonyl) adenine [EHNA] inhibitory assay using the Hitachi 7170 autoanalyzer.
RESULTS
The rates of abnormally high total ADA activity were 100% for ALL, 60.8% for AML, and 50% for CML. In isoenzyme pattern, there was a clear difference between ALL and AML. High level of ADA1 activity was found in patients with ALL (P <0.01). The ADA1/ADA2 ratio was significantly higher (P <0.001) in ALL than AML. There was a correlation between ADA1 and absolute number of peripheral blasts in AML (r=0.840).
CONCLUSIONS
It is concluded that the measurement of ADA isoenzyme may be a useful biochemical marker for leukemic diagnosis.

Keyword

Adenosine deaminase isoenzyme; Leukemia; Erythro-9- (2-hydroxy-3-nonyl) adenine [EHNA]

MeSH Terms

Adenine
Adenosine Deaminase*
Adenosine*
Biomarkers
Deamination
Diagnosis
Humans
Inosine
Isoenzymes
Leukemia*
Leukemia, Myelogenous, Chronic, BCR-ABL Positive
Leukemia, Myeloid, Acute
Lymphoma
Metabolism
Precursor Cell Lymphoblastic Leukemia-Lymphoma
Tissue Distribution
Adenine
Adenosine
Adenosine Deaminase
Inosine
Isoenzymes