Table 5

Overview of haemototoxicity reported in the azathioprine group (n=41)

Patient IDTPMT genotypeTPMT activity at baseline (nmol 6-MTG/g Hb/h)*Adverse eventMaximum 6-TGN level observed after onset of adverse event (pmol/8×108 RBC)Premature withdrawalPrimary reason for withdrawal
703*1/*3A19Leucopenia600YesLack of cooperation
706*1/*3A22Leucopenia370YesIntolerable adverse event (leucopenia)
728*1/*3A19Leucopenia/anaemia944YesIntolerable adverse event (leucopenia)
742*1/*138Leucopenia/anaemia604YesIntolerable adverse event (hyperamylasaemia)
831*1/*148Leucopenia/anaemia978YesLack of cooperation
  • * TPMT activity <23 nmol 6-MTG/g Hb/h is considered an intermediate metaboliser TPMT phenotype.23

  • Hb, haemoglobin; MTG, methyl-thioguanine; RBC, red blood cell; TGN, thioguanine nucleotides; TPMT, thiopurine methyltransferase.