Implementation gaps in phenylketonuria management: a multicenter clinician survey from Turkiye

Phenylketonuria (PKU) is a rare inherited metabolic disorder requiring lifelong dietary management and regular monitoring to maintain metabolic control. Although international guidelines provide clear recommendations, their implementation in real-world clinical practice may be limited by structural and patient-related factors. This study aimed to evaluate clinician-reported PKU management practices across multiple centers in Turkiye and to identify key barriers to guideline implementation.

A descriptive cross-sectional survey was conducted among metabolic specialists from multiple centers across Turkiye during a scientific meeting. The questionnaire, developed based on international PKU guidelines, assessed monitoring practices, dietary management, and barriers to implementation. Participants reported both theoretically recommended and clinician-reported monitoring frequencies across different age groups. Data were analyzed using descriptive statistics, and differences between recommended and reported practices were evaluated using the Stuart-Maxwell test.

Sixteen metabolic specialists from 16 centers participated. While 69% of clinicians recommended weekly monitoring in infants, only 25% reported achieving this in practice (p = 0.018). Similar discrepancies were observed in adolescents and adults (p = 0.009 and p = 0.043, respectively), whereas no significant difference was found in children aged 1-12 years (p = 0.122). Home-based dried blood spot monitoring was not routinely used in 69% of centers. The most important barriers to optimal monitoring included lack of home sampling systems, geographical distance, and work or school-related constraints. Substantial variability was also observed in dietary management practices, including protein prescription and protein substitute use.

PKU management in Turkiye is characterized by a clear gap between guideline recommendations and clinician-reported practices, primarily driven by structural and implementation-related barriers. These findings highlight the importance of strengthening healthcare infrastructure, improving access to monitoring tools, and integrating patient-centered strategies to enhance the real-world implementation of evidence-based care in rare diseases.