Objective Inborn errors of metabolism are a significant public health problem in Saudi Arabia. Incidence is estimated to be 5 times higher than in the US. Adherence to a special diet is essential for management of phenylketonuria (PKU) in order to prevent developmental disability. Our aim is to identify risk factors that lead to inadequate control over PKU and its diet for patients at King Faisal Specialist Hospital & Research Centre in Saudi Arabia to improve nutritional management.

Methods Qualitative study: assessed nutritional knowledge, attitudes and practices: 5 interviews and 2 focus groups with health care providers; 6 interviews with patients; and 17 interviews with families.

Quantitative study: anthropometric measurements, dietary intake, phenylalanine blood levels, developmental assessments, and questionnaires with 40 PKU patients and their families.

Results Major qualitative themes: lack of sufficient services; limited dietary knowledge; limited resources; social and emotional attitudes towards diet and compliance.

Quantitative initial results Of the 40 patients 62% have developmental disabilities ranging from mild to severe. This is due to delayed diagnosis (77%), poor compliance (92%), limited knowledge or a combination of these.

Conclusion In Saudi Arabia targeted nutrition management programmes need to be developed to support patients and their families. Education and metabolic care services need major improvements to be able to deliver optimal care.