Low Rates of Growth in Paediatric Lung and Heart-Lung Transplant Recipients and Effects on Spirometry

Purpose A retrospective study of paediatric lung and heart-lung transplant (LTx) recipients to assess growth and its relationship with spirometric indices. Methods Analyses of relationships between serially assessed age, height, weight, forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) were undertaken. Serial spirometry at identical heights were analysed as means. Percentile height-for-age was calculated from the CDC 2000 dataset.1 95% confidence intervals are presented in parentheses after values. Results 42 LTx recipients ≤17 years (median at LTx = 13.6 years, 62% female) had spirometry and biometric data available. LTx indications included Cystic Fibrosis (n = 20) and Obliterative Bronchiolitis (n = 6). Median follow-up was 1.24 years (0.13-2.35). There was no significant difference between median biometric or spirometry value changes if recipients with 10cm. The median increase in FVC was 0.94L (0.15-1.72). Median predicted FVC and FEV1 were 67.8% (37.5-98.2) and 58.3% (27.8-88.8) of predicted respectively. Growth was not above expected for age with median change in height for age of -2.9 percentiles (-36.2-30.4). LTx recipients 1year follow-up) had a median height change of 7.5cm (-2.1-17.1 and median age-matched height percentile change of-4.55 percentiles (-22.6-13.47). Conclusion Most paediatric LTx recipients did not significantly change height after LTx. Unlike other solid organ Tx, where growth catch-up is expected, this does not occur.2 Additionally, graft function does not appear to impact growth trajectory. While significant steroid exposure contributes, further research will need to delineate the interplay of LTx on pubertal growth, immunosuppression and the effects of underlying conditions.