Abstract :

ABSTRACT

The AlloMap® Gene Expression Test is a non-invasive screening tool approved for use in heart transplant recipients 15 years of age and older. Experience with AlloMap® in pediatric heart transplant recipients is limited. We aimed to describe differences in his AlloMap® scores observed in pediatric heart transplant recipients. This is a retrospective study of all pediatric heart transplant recipients evaluated by his AlloMap® at a single institution between 2013 and 2014. All possible ratings were recorded. Additional variables recorded at the time of each AlloMap® score include immunosuppressive therapy, patient demographics, and endocardial biopsy (EMB) results. Patients who underwent another solid organ transplant or multiple solid organ transplants were excluded. Her 100 AlloMap® scores were obtained from 42 patients, and her mean age at implantation was 4.3 years. Her median AlloMap® score for all patients was 32 (IQR: 30-35). Of the 100 AlloMap® scores, 10% were collected from her 12-year-old patient. There was little difference in the median score between age groups (p=0.143). Forty-five scores had a concomitant biopsy. Twenty-eight (62%) patients had ISHLT grade 0 and 16 (36%) had ISHLT grade 1 rejection. AlloMap® scores were higher in patients with evidence of ISHLT grade 1 acute cellular rejection (ACR) on EMB (p=0.044). AlloMap® scores were similar across all immunosuppression regimens (p=0.403), with TAC+MMF (n=43) and TAC+SIR (n=27) being the most commonly used regimens. In patients with multiple AlloMap® scores, the mean change from baseline in AlloMap® score was 2 (IQR, 2-5), with no significant change in biopsy findings. Among pediatric heart transplant recipients, patients with ISHLT Grade 1 rejection had higher AlloMap® scores than those with ISHLT Grade 0 rejection, although AlloMap® scores were affected by patient age and immunity. It did not appear to be affected by suppressive therapy. Further research is needed to confirm the results of this study and to determine the role of her AlloMap® in monitoring pediatric patients after transplantation.

KEYWORDS

Aromap®; heart transplantation in children; gene expression; immunosuppressive.