Newborn screening of homocystinuria: quantitative analysis of total homocyst(e)ine on dried blood spot by liquid chromatography with fluorimetric detection.
Identification of homocystinuric newborns is hindered by the pitfalls of neonatal screening programs. We propose a fluorimetric HPLC method with a rapid pre-analytical step for homocysteine determination from neonatal dried blood spot cards. Homocysteine in blood spots sampled among 2000 healthy newborns on living day 4, averaged 2.92+/-2.07 microM (range 0.4-7.5). In eight homocystinuric control children, mean values were 61.71+/-52.84 microM (range 18.9-145.7). The method showed a good linearity (r=0.999), precision (RSD<7%) and recovery (95%). The correlation between blood spots and plasma samples was r=0.90. This method has all the essential features for a homocystinuria screening program: an easy and rapid pre-analytical step combined with method linearity and precision.
Accinni
Roberto
R
Institute of Clinical Physiology, CNR Section of Milan, Niguarda Ca' Granda Hospital, P.zza Ospedale Maggiore 3, 20162 Milan, Italy. ifcnigmi@tin.it
Campolo
Jonica
J
Parolini
Marina
M
De Maria
Renata
R
Caruso
Raffaele
R
Maiorana
Andrea
A
Galluzzo
Cino
C
Bartesaghi
Silvia
S
Melotti
Davide
D
Parodi
Oberdan
O
D000596:Amino Acids / Q000737:chemistry; D002138:Calibration; D002853:Chromatography, Liquid; D006710:Homocysteine / Q000032:analysis* / Q000097:blood / Q000652:urine; D006712:Homocystinuria / Q000097:blood / Q000175:diagnosis*; D006801:Humans; D007202:Indicators and Reagents; D007231:Infant, Newborn; D015997:Neonatal Screening / Q000379:methods*; D010949:Plasma / Q000737:chemistry; D015203:Reproducibility of Results; D013050:Spectrometry, Fluorescence; D013438:Sulfhydryl Compounds / Q000097:blood
D000596:Amino Acids; D007202:Indicators and Reagents; D013438:Sulfhydryl Compounds; D006710:Homocysteine