A Retrospective Chart Review and Infant Feeding Survey in the Irish Phenylketonuria (PKU) Population (2016–2020)

Phenylketonuria (PKU) is an inherited disorder of protein metabolism. It is generally treated using dietary management with limited intake of phenylalanine (Phe). Partial breastfeeding (BF) is encouraged among mothers of infants with PKU, together with a Phe-free mixture of synthetic amino acids. We aimed to describe our current BF rates and complementary feeding practices, as well as examining parental experiences of infant feeding. The aim was to better understand the challenges faced by families so improvements can be made to clinical care. A chart review was carried out on 39 PKU patients, examining the BF rate and duration, use of second stage synthetic protein (SP) and average complementary feeding age. A parental questionnaire on complementary feeding and BF experience was designed. 26% of babies were partially breastfed at three months. 70% of mums would like to have breastfed for longer and cited PKU as a reason for stop-ping. 52% parents reported challenges during the complementary feeding process including food refusal, protein calculation and anxiety around maintaining good Phe levels. Suggestions to improve BF continuation and duration include active promotion of the benefits and suitability, access to lactation consultant and peer support. The delay in introducing a second stage SP may contribute to long-term bottle use for SP. Improved patient education, written resources and sup-port is necessary to improve food choices and long term acceptance of SP.