The identification of somatic
variation is crucial to confirm the heritability of retinoblastoma. We and others have previously shown that, when tumour DNA is unavailable, cell-free DNA (cfDNA) ...derived from aqueous humour (AH) can be used to identify somatic
pathogenic variation. Here we report
pathogenic variant detection, as well as cfDNA concentration in an extended cohort of 75 AH samples from 68 patients. We show cfDNA concentration is highly variable and significantly correlated with the collection point of the AH. Cell-free DNA concentrations above 5 pg/µL enabled the detection of 93% of known or expected
pathogenic variants. In AH samples collected during intravitreal chemotherapy treatment (Tx), the yield of cfDNA above 5 pg/µL and subsequent variant detection was low (≤46%). However, AH collected by an anterior chamber tap after one to three cycles of primary chemotherapy (Dx1+) enabled the detection of 75% of expected pathogenic variants. Further limiting our analysis to Dx1+ samples taken after ≤2 cycles (Dx ≤ 2) provided measurable levels of cfDNA in all cases, and a subsequent variant detection rate of 95%. Early AH sampling is therefore likely to be important in maximising cfDNA concentration and the subsequent detection of somatic
pathogenic variants in retinoblastoma patients undergoing conservative treatment.
Neonates with absent-or-reversed umbilical artery end-diastolic flow (AREDF) are at an increased risk of feeding problems. In this retrospective study, authors evaluated the incidence of feed ...intolerance in 213 preterm neonates (January 2017-May 2022) with AREDF. The median (IQR) gestation and birth weight were 32 (30, 33) wk and 1120 (840, 1425) g, respectively. Of 213 neonates, 103 (48.4%; 95% CI 41.5%, 55.3%) neonates developed feed intolerance. Twelve of 213 neonates developed any stage necrotizing enterocolitis (NEC) (5.6%; 95% CI 2.9%, 9.6%) at a median age of 10 d. On multivariate regression, gestation was the only independent predictor of feed intolerance (OR 1.48; 95% CI 1.28, 1.70; for every 1 wk decrease below 36 wk). Almost 50% of preterm neonates with AREDF develop feed intolerance. Alternative feeding strategies warrant exploration to optimise nutrition in these neonates.