Usefulness of the measurement of azathioprine metabolites in the assessment of non-adherence.
Azathioprine is a thiopurine immunosuppressive antimetabolite used to chronically treat inflammatory bowel disease and autoimmune hepatitis. Azathioprine treatment is a long-term therapy and therefore it is at risk for non-adherence, which is considered an important determinant of treatment inefficacy. Measurement of 6-thioguanine and 6-methylmercaptopurine nucleotides has been recently suggested as a screener for non-adherence detection. We describe four young patients in which non-adherence to azathioprine therapy was detected only through the measurement of drug metabolite concentrations, and the criterion for non-adherence was undetectable metabolite levels. After the identification of non-adherence, patients and their families were approached and the importance of a correct drug administration was thoroughly enlightened and discussed; this allowed obtaining a full remission in all subjects. Our observations support the use of undetectable metabolite levels as indicators of non-adherence to therapy in azathioprine treated patients. The additional level of medical supervision given by this assay allows getting a better adherence to medical treatment, which results in an improvement in the response to therapy; these benefits may justify the costs associated with the assay.
Department of Life Sciences, University of Trieste, Italy.
Gabriele
G
Stocco
Margherita
M
Londero
Angelo
A
Campanozzi
Stefano
S
Martelossi
Sara
S
Marino
Noelia
N
Malusa
Fiora
F
Bartoli
Giuliana
G
Decorti
Alessandro
A
Ventura
D000293:Adolescent; D001379:Azathioprine / Q000378:metabolism* / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006150:Guanine Nucleotides / Q000097:blood*; D019693:Hepatitis, Autoimmune / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy; D006801:Humans; D007166:Immunosuppressive Agents / Q000378:metabolism* / Q000627:therapeutic use*; D015212:Inflammatory Bowel Diseases / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy; D008297:Male; D055118:Medication Adherence; D015122:Mercaptopurine / Q000031:analogs & derivatives* / Q000097:blood; D013873:Thionucleotides / Q000097:blood*; D055815:Young Adult
D006150:Guanine Nucleotides; D007166:Immunosuppressive Agents; D013873:Thionucleotides; C003964:6-thioguanylic acid; C010240:6-methylthiopurine; D015122:Mercaptopurine; D001379:Azathioprine