Viapath’s Porphyria Laboratory Now Offers An Urgent Urine Porphobilinogen (PBG) Service
Viapath’s Porphyria Laboratory, headed by Dr Joanne Marsden, is one of only two Supraregional Assay Service (SAS) designated laboratories in the UK offering diagnosis of rare porphyria disorders.
The porphyrias are a group of mainly inherited diseases of the haem synthesis pathway. The porphyrias are classified into acute and cutaneous depending on their presenting symptoms. There are eight different porphyrias and they can present with symptoms such as severe abdominal pain, blisters or photosensitivity. Porphyria are diagnosed using urine, blood and stool specimens and techniques such as ion exchange chromatography, spectrophotometry and fluorimetry and more recently, genetic analysis.
Patients with an acute porphyria can have life threatening attacks that usually require admission to hospital and specific treatment. The biochemical hallmark of an acute porphyria attack is the increase in urine excretion of urine porphobilinogen (PBG) that can increase significantly during an attack. Recent guidelines from the British and Irish Porphyria Network (BIPNET) have recommended that urine is analysed promptly for quantitative PBG concentration (Ann Clin Biochem 2016, in press).
Only a few laboratories are able to perform the analysis due to restraints in technology and staff training. The Porphyria Laboratory is now able to offer an urgent weekday service for PBG analysis (Monday to Friday during working hours) to internal and external customers. Results will be reported by telephone on the same day of analysis. The method is based on ion-exchange chromatography and a colour reaction with Ehrlich’s reagent. It is recommended that a positive result is followed up by providing blood and stool samples to confirm the type of porphyria. The patient is also referred to the Porphyria Clinic for advice on management of the disease. Porphyria genetics are also available and performed in Viapath’s Molecular Department for inheritance studies.
Please contact the Porphyria Laboratory on 020 3299 3856 to discuss.
