PNP (Purine nucleoside phosphorylase) enzyme assay
- Description
- Purine nucleoside phosphorylase (PNP) deficiency catalyses the conversion of the purine nucleosides inosine, deoxyinosine, guanosine and deoxyguanosine to the respective bases. The enzyme is assayed in red cell lysates using inosine as the substrate with products of the reaction separated from substrate by HPLC. This test is not currently included in the laboratory's UKAS scope of accreditation to ISO15189:2022.
- Clinical details
Inherited severe combined immunodeficiency. Children typically present with recurrent infections due to absent T-cell immunity. There may be B-cell dysfunction leading to autoimmunity. Neurological abnormalities are present in about 50% of patients. Uric acid in plasma may be low, but not always. The disorder is autosomal recessive.
- Related condition
- Reference range
3000 – 7000
- Units
nmol/h/mgHb
- Testing site
- Synnovis : Reference Services : Blackfriars Hub
- Laboratory
- Inherited Metabolic Disease
- Sample type and volume required
4 mL blood EDTA (purple top)
- Storage and transport
Store in fridge, ( don’t freeze). Transport to lab within 24hrs
- Turnaround time
1 week
- Contacts
Inherited Metabolic Diseases Unit at Blackfriars Hub
Phone: 020 4591 0070
IMD Duty Biochemist: 07592 502653
Email: ClinicalScientistIMD@synnovis.co.uk
Reference Chemistry
Floor 1, Synnovis hub
Friars Bridge Court
41-43 Blackfriars Road
London
SE1 8NZ