RT Journal Article SR Electronic T1 How to useā€¦ white blood cell enzyme assays JF Archives of disease in childhood - Education & practice edition JO Arch Dis Child Educ Pract Ed FD BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health SP 143 OP 147 DO 10.1136/archdischild-2015-309964 VO 102 IS 3 A1 James Davison YR 2017 UL http://ep.bmj.com/content/102/3/143.abstract AB White blood cell (leucocyte) enzyme assays are an important part of the investigation of potential metabolic disorders, in particular, lysosomal storage disorders. It is imperative that appropriate tests are selected, and that knowledge of the limitations of these assays is applied to avoid erroneous conclusions about confirmation or exclusion of diagnoses.