Abstract
Background: Detection of amino acids (AA), acylcarnitines (AC), and guanidinoacetate (GAA) in dried blood spots by tandem mass spectrometry has made it possible to detect different inborn errors of metabolism in neonatal screening programs. Despite its proven sensitivity many issues related to sample preparation remain unsolved. Hematocrit has a profound effect on blood viscosity, and may thereby influence flux and diffusion properties of the blood. As newborn infants show a considerable interindividual variability of hematocrit levels, we investigated its effect on levels of AA and AC in dried blood spots. Methods: Blood samples with defined hematocrit levels (20%, 30%, 40%, 50%, 60%) were produced by diluting blood cells with plasma from a single donor. Forty dried blood spots were made for each hematocrit level and a central as well as a peripheral 3 mm disk was punched and analysed for AA, AC, and GAA, respectively. Results: Levels of most AA and GAA increased significantly with increasing hematocrit (p < 0.001), while the effect of hematocrit on some AA was less pronounced. Total AC, free carnitine, some long, medium and short chain AC correlated positively with hematocrit levels (p < 0.001). In samples with low hematocrit, levels of most AA and free carnitine were higher in the peripheral than in the central disk (p < 0.0001). Conclusions: Both hematocrit and position of the disk within the dried blood spot have a significant and sometimes additive effect on levels of AA, AC and GAA in dried blood spots. Theoretically, diagnoses may be missed depending on hematocrit and position of the disk.
| Original language | English |
|---|---|
| Pages (from-to) | 27-31 |
| Number of pages | 5 |
| Journal | Clinica Chimica Acta |
| Volume | 373 |
| Issue number | 1-2 |
| DOIs | |
| State | Published - Nov 1 2006 |
Fingerprint
Keywords
- Acylcarnitine
- Amino acid
- Blood spot
- Hematocrit
- Neonatal
- Screening
ASJC Scopus subject areas
- Biochemistry
- Clinical Biochemistry
Cite this
Influence of hematocrit and localisation of punch in dried blood spots on levels of amino acids and acylcarnitines measured by tandem mass spectrometry. / Holub, Margareta; Tuschl, Karin; Ratschmann, Rene; Strnadová, Kristina Anna; Mühl, Adolf; Heinze, Georg; Sperl, Wolfgang; Bodamer, Olaf A.
In: Clinica Chimica Acta, Vol. 373, No. 1-2, 01.11.2006, p. 27-31.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Influence of hematocrit and localisation of punch in dried blood spots on levels of amino acids and acylcarnitines measured by tandem mass spectrometry
AU - Holub, Margareta
AU - Tuschl, Karin
AU - Ratschmann, Rene
AU - Strnadová, Kristina Anna
AU - Mühl, Adolf
AU - Heinze, Georg
AU - Sperl, Wolfgang
AU - Bodamer, Olaf A.
PY - 2006/11/1
Y1 - 2006/11/1
N2 - Background: Detection of amino acids (AA), acylcarnitines (AC), and guanidinoacetate (GAA) in dried blood spots by tandem mass spectrometry has made it possible to detect different inborn errors of metabolism in neonatal screening programs. Despite its proven sensitivity many issues related to sample preparation remain unsolved. Hematocrit has a profound effect on blood viscosity, and may thereby influence flux and diffusion properties of the blood. As newborn infants show a considerable interindividual variability of hematocrit levels, we investigated its effect on levels of AA and AC in dried blood spots. Methods: Blood samples with defined hematocrit levels (20%, 30%, 40%, 50%, 60%) were produced by diluting blood cells with plasma from a single donor. Forty dried blood spots were made for each hematocrit level and a central as well as a peripheral 3 mm disk was punched and analysed for AA, AC, and GAA, respectively. Results: Levels of most AA and GAA increased significantly with increasing hematocrit (p < 0.001), while the effect of hematocrit on some AA was less pronounced. Total AC, free carnitine, some long, medium and short chain AC correlated positively with hematocrit levels (p < 0.001). In samples with low hematocrit, levels of most AA and free carnitine were higher in the peripheral than in the central disk (p < 0.0001). Conclusions: Both hematocrit and position of the disk within the dried blood spot have a significant and sometimes additive effect on levels of AA, AC and GAA in dried blood spots. Theoretically, diagnoses may be missed depending on hematocrit and position of the disk.
AB - Background: Detection of amino acids (AA), acylcarnitines (AC), and guanidinoacetate (GAA) in dried blood spots by tandem mass spectrometry has made it possible to detect different inborn errors of metabolism in neonatal screening programs. Despite its proven sensitivity many issues related to sample preparation remain unsolved. Hematocrit has a profound effect on blood viscosity, and may thereby influence flux and diffusion properties of the blood. As newborn infants show a considerable interindividual variability of hematocrit levels, we investigated its effect on levels of AA and AC in dried blood spots. Methods: Blood samples with defined hematocrit levels (20%, 30%, 40%, 50%, 60%) were produced by diluting blood cells with plasma from a single donor. Forty dried blood spots were made for each hematocrit level and a central as well as a peripheral 3 mm disk was punched and analysed for AA, AC, and GAA, respectively. Results: Levels of most AA and GAA increased significantly with increasing hematocrit (p < 0.001), while the effect of hematocrit on some AA was less pronounced. Total AC, free carnitine, some long, medium and short chain AC correlated positively with hematocrit levels (p < 0.001). In samples with low hematocrit, levels of most AA and free carnitine were higher in the peripheral than in the central disk (p < 0.0001). Conclusions: Both hematocrit and position of the disk within the dried blood spot have a significant and sometimes additive effect on levels of AA, AC and GAA in dried blood spots. Theoretically, diagnoses may be missed depending on hematocrit and position of the disk.
KW - Acylcarnitine
KW - Amino acid
KW - Blood spot
KW - Hematocrit
KW - Neonatal
KW - Screening
UR - http://www.scopus.com/inward/record.url?scp=33747877255&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33747877255&partnerID=8YFLogxK
U2 - 10.1016/j.cca.2006.04.013
DO - 10.1016/j.cca.2006.04.013
M3 - Article
C2 - 16797519
AN - SCOPUS:33747877255
VL - 373
SP - 27
EP - 31
JO - Clinica Chimica Acta
JF - Clinica Chimica Acta
SN - 0009-8981
IS - 1-2
ER -