Porphyria Laboratory Diagnostics in Thailand

Sarawut Junnu and Chatchawan Srisawat

Department of Biochemistry, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand

Correspondence to Chatchawan Srisawat (MD, PhD),
Department of Biochemistry, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand. Email: chatchawan.sri@mahidol.ac.th


The porphyrias are a group of disorders caused by defective enzymes in the heme biosynthetic pathway; there are 7 main types of porphyrias, presenting with various clinical symptoms ranging from dermatological to neurological manifestations. Because the diseases are quite rare, many patients are often misdiagnosed clinically. Therefore, the laboratory investigations are necessary for accurate diagnosis. In this study, the porphyria cases confirmed by our laboratory at Siriraj Hospital are reported. Urine and blood samples from the patients with clinical suspicions of porphyrias from Siriraj Hospital and other hospitals in Thailand during 2000 to 2019 were sent to the service laboratory at the Department of Biochemistry, Siriraj Hospital, for porphyria investigations. Porphyrins in random urine specimens were analyzed using high-performance liquid chromatography (HPLC) techniques, while delta-aminolevulinic acid and porphobilinogen were determined using spectrophotometric assays; the values were then normalized against urine creatinine. Plasma and erythrocyte specimens were analyzed for the presence of porphyrins using the fluorescence spectroscopic method. Nineteen patients were confirmed by the laboratory to have porphyrias as follows; porphyria cutanea tarda (13 cases), variegate porphyria (3 cases), acute intermittent porphyria, congenital erythropoietic porphyria, and erythropoietic protoporphyria (1 case each). Although porphyrias are rather uncommon, 5 types of porphyrias were identified at Siriraj Hospital, with porphyria cutanea tarda as the most common type. Awareness of porphyrias and appropriate laboratory investigations can lead to accurate diagnosis and effective management of those disorders.

Keywords: Porphyria, Porphyrin, Delta-aminolevulinic acid, Porphobilinogen, Acute intermittent porphyria, Congenital erythropoietic porphyria, Porphyria cutanea tarda, Variegate porphyria, Erythropoietic protoporphyria