Background: Erythropoietic protoporphyria (EPP) is a rare disorder of heme biosynthesis hallmarked by early-onset photosensitivity and mainly due to defective ferrochelatase activity leading to increased erythrocyte protoporphyrin IX (PPIX) levels. Evidence regarding the relationship between erythrocyte PPIX concentration and photosensitivity is limited. Methods: To investigate the relationship between free erythrocyte PPIX (FEP) concentration; routine laboratory tests, particularly iron metabolism biomarkers; and ultraviolet (UV) A/visible light phototesting findings, 20 genetically confirmed EPP and one XLPP treatment-naive patients were included in our study. They underwent UVA and visible light phototesting. On the same day, blood samples were collected for measurement of FEP, serum iron, transferrin, transferrin saturation, and ferritin, 25-hydroxyvitamin D, and liver enzyme levels. Results: Median FEP concentration at the time of phototesting was 57.50 (IQR: 34.58-102.70) μg/g of Hb. UVA and visible light phototesting were positive in 9 (42.9%) and 8 (38.1%) patients, respectively. Median FEP concentration was significantly higher in UVA phototest–positive patients than in those negative (64.37 [IQR: 57.45-121.82] vs 45.35 [IQR: 24.53-74.61] μg/g of Hb, respectively; P =.04486). Similarly, UVA photosensitive individuals had significantly lower median serum iron levels (61.5 [IQR: 33.5-84] μg/dL vs 109 [IQR: 63.25-154] μg/dL, respectively; P =.01862) and transferrin saturation values (15.005 [IQR: 7.0775-18.41] % vs 29.645 [IQR: 17.8225-34.3575] %; P =.0109) than those negative. Conclusions: Our study demonstrates that UVA phototest positivity is associated with higher FEP concentration and lower transferrin saturation and serum iron concentration in EPP.

Ultraviolet A phototest positivity is associated with higher free erythrocyte protoporphyrin IX concentration and lower transferrin saturation values in erythropoietic protoporphyria / G. Genovese, C.A. Maronese, C. Moltrasio, R. Piccinno, D.A. Marletta, G. De Luca, G. Graziadei, F. Granata, E. Di Pierro, M.D. Cappellini, A.V. Marzano. - In: PHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE. - ISSN 0905-4383. - (2021). [Epub ahead of print] [10.1111/phpp.12727]

Ultraviolet A phototest positivity is associated with higher free erythrocyte protoporphyrin IX concentration and lower transferrin saturation values in erythropoietic protoporphyria

A.V. Marzano
Ultimo
2021

Abstract

Background: Erythropoietic protoporphyria (EPP) is a rare disorder of heme biosynthesis hallmarked by early-onset photosensitivity and mainly due to defective ferrochelatase activity leading to increased erythrocyte protoporphyrin IX (PPIX) levels. Evidence regarding the relationship between erythrocyte PPIX concentration and photosensitivity is limited. Methods: To investigate the relationship between free erythrocyte PPIX (FEP) concentration; routine laboratory tests, particularly iron metabolism biomarkers; and ultraviolet (UV) A/visible light phototesting findings, 20 genetically confirmed EPP and one XLPP treatment-naive patients were included in our study. They underwent UVA and visible light phototesting. On the same day, blood samples were collected for measurement of FEP, serum iron, transferrin, transferrin saturation, and ferritin, 25-hydroxyvitamin D, and liver enzyme levels. Results: Median FEP concentration at the time of phototesting was 57.50 (IQR: 34.58-102.70) μg/g of Hb. UVA and visible light phototesting were positive in 9 (42.9%) and 8 (38.1%) patients, respectively. Median FEP concentration was significantly higher in UVA phototest–positive patients than in those negative (64.37 [IQR: 57.45-121.82] vs 45.35 [IQR: 24.53-74.61] μg/g of Hb, respectively; P =.04486). Similarly, UVA photosensitive individuals had significantly lower median serum iron levels (61.5 [IQR: 33.5-84] μg/dL vs 109 [IQR: 63.25-154] μg/dL, respectively; P =.01862) and transferrin saturation values (15.005 [IQR: 7.0775-18.41] % vs 29.645 [IQR: 17.8225-34.3575] %; P =.0109) than those negative. Conclusions: Our study demonstrates that UVA phototest positivity is associated with higher FEP concentration and lower transferrin saturation and serum iron concentration in EPP.
erythropoietic protoporphyria; photosensitivity; phototesting; porphyria; protoporphyrin IX; UVA phototesting
Settore MED/35 - Malattie Cutanee e Veneree
22-ago-2021
Article (author)
File in questo prodotto:
File Dimensione Formato  
Photoderm Photoimm Photomed - 2021 - Genovese - Ultraviolet A phototest positivity is associated with higher free.pdf

accesso aperto

Descrizione: Online first
Tipologia: Publisher's version/PDF
Dimensione 662.29 kB
Formato Adobe PDF
662.29 kB Adobe PDF Visualizza/Apri
Pubblicazioni consigliate

Caricamento pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/2434/891693
Citazioni
  • ???jsp.display-item.citation.pmc??? 3
  • Scopus 3
  • ???jsp.display-item.citation.isi??? 3
social impact