RESUMO
El metotrexato es un antineoplásico muy utilizado y eficaz en neoplasias como las leucemias, los linfomas y los osteosarcomas. La toxicidad renal es un efecto secundario indeseable que se pretende evitar con una alcalinización urinaria e hiperhidratación eficaz. En caso de intoxicación aguda se establece el uso de carboxipeptidasa G2, una enzima que provoca la hidrólisis del metotrexato en sus metabolitos inactivos. Por su parte, el uso de glutamina durante el tratamiento oncológico previene parte de los efectos indeseables secundarios a éste. Se presenta el caso clínico de un adolescente afectado de linfoma no hodgkiniano en tratamiento con glutamina, que tras la administración de un tercer ciclo de metotrexato (5g/m2) presentó un cuadro de insuficiencia renal que precisó la administración de carboxipeptidasa, con descenso no satisfactorio de las concentraciones de metotrexato en sangre, si bien no se pudo diferenciar la fracción activa del metabolito inactivo por carecer de esta técnica en España. Se revisó la bibliografía sobre la interacción de glutamina y metotrexato y se discutió su fisiopatología sobre un posible papel de la glutamina como favorecedora de la toxicidad por metotrexato (AU)
Methotrexate (MTX) is widely used as anticancer agent in various malignancies, including acute lymphoblastic leukaemia, lymphoma and osteosarcoma. High doses of MTX may cause acute renal dysfunction. Nephrotoxicity is prevented by the use of alkalinization and hydration. More recently Carboxypeptidase-G2, a recombinant bacterial enzyme that rapidly hydrolyzes MTX to inactive metabolites, has become available for the treatment of acute nephrotoxicity. On the other hand, glutamine is usually administered in oncology treatments to avoid other side effects. We report a case of an adolescent who was diagnosed with T lymphoblastic lymphoma. He was receiving treatment with glutamine when the third course of methotrexate was administered (5g/m2) and he suffered a deterioration in his renal function. Carboxypeptidase was used but the methotrexate serum concentration reduction was not satisfactory. The technique to assess the amount of enzyme-inactivated methotrexate by quantification of MTX metabolites is not available in our country, therefore, the concentrations of MTX may be overestimated. The literature was reviewed to study the influence of glutamine on delayed methotrexate elimination which may lead to acute toxicity (AU)
Assuntos
Humanos , Masculino , Adolescente , Carboxipeptidases/farmacocinética , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Metotrexato/toxicidade , Interações Medicamentosas , Antineoplásicos/toxicidade , Injúria Renal Aguda/induzido quimicamenteRESUMO
Methotrexate (MTX) is widely used as anticancer agent in various malignancies, including acute lymphoblastic leukaemia, lymphoma and osteosarcoma. High doses of MTX may cause acute renal dysfunction. Nephrotoxicity is prevented by the use of alkalinization and hydration. More recently Carboxypeptidase-G2, a recombinant bacterial enzyme that rapidly hydrolyzes MTX to inactive metabolites, has become available for the treatment of acute nephrotoxicity. On the other hand, glutamine is usually administered in oncology treatments to avoid other side effects. We report a case of an adolescent who was diagnosed with T lymphoblastic lymphoma. He was receiving treatment with glutamine when the third course of methotrexate was administered (5 g/m(2)) and he suffered a deterioration in his renal function. Carboxypeptidase was used but the methotrexate serum concentration reduction was not satisfactory. The technique to assess the amount of enzyme-inactivated methotrexate by quantification of MTX metabolites is not available in our country, therefore, the concentrations of MTX may be overestimated. The literature was reviewed to study the influence of glutamine on delayed methotrexate elimination which may lead to acute toxicity.
