Diagnosis of developmental delay: the metabolic biochemist's approach

Abstract

The clinical detail of 'developmental delay' or the shortened form 'Dev Delay' upon a request form often brings gloom to the heart of a Metabolic Biochemist. The comment often seems to have been written either as a detail of last resort or in such haste that other more important details are omitted. The tests required are often complex and may have to be referred to reference laboratories and all too often, the wrong sample taken at the wrong time, into an incorrect container has been sent and all from a patient in whom it is difficult to obtain samples. Cooperation and communication between all the professionals, paediatricians, biochemists, geneticists and others leads to much improved diagnosis and management of patients as well as targeting limited resources appropriately. It is important to carefully plan the investigations of a child with developmental delay early diagnosis is crucial for several reasons (Table 1). Early identification of developmental delay relies on careful clinical skills as well as developmental screening. 1 Many important treatable biochemical causes of developmental delay have a slowly progressive, almost insidious clinical course which can only be identified by careful observation and detailed assessment many children with these conditions are diagnosed extremely late. 2'3 If such assessments are