Utilization of dried blood spot citrulline level as a noninvasive method for monitoring graft function following intestinal transplantation.
BACKGROUND
Citrulline concentrations have been proposed as a marker for intestinal allograft rejection. We instituted dried blood spot (DBS) specimen monitoring of citrulline to simplify sample collection posttransplant. This study demonstrates the correlation between plasma and dried blood spot specimen citrulline concentrations after intestinal transplantation.


METHODS
Plasma and DBS samples were analyzed by hydrophilic interaction chromatography tandem mass spectrometry. Comparison of the strength of linear correlation was made according to the type of surgery, sonication time, DBS citrulline levels, and the time interval between the blood sample collection and the assay date.


RESULTS
A very strong linear correlation exists between the plasma and DBS citrulline concentrations (r=0.87; P<0.001). The correlation between plasma and DBS citrulline concentrations was maintained when evaluating only the intestinal transplant recipients. There was no significant difference in the strength of linear correlation according to sonication time, cirtrulline concentrations, or length of time to assay date.


CONCLUSIONS
DBS citrulline monitoring will ease sample collection following intestinal transplantation and improve the ability to detect intestinal dysfunction and rejection by a noninvasive means.
Yu
Hee Chul
HC
Department of Surgery, Division of Transplantation, University of Miami School of Medicine, Miami, FL 33136, USA.
Tuteja
Sony
S
Moon
Jang Il
JI
Kleiner
Gary I
GI
Conanan
Lobella
L
Gaynor
Jeffrey J
JJ
Kato
Tomoaki
T
Levi
David M
DM
Nishida
Seigo
S
Selvaggi
Gennaro
G
Gandia
Carlos
C
Weppler
Debbie
D
Esquenazi
Violet
V
Ruiz
Phillip
P
Miller
Joshua
J
Tzakis
Andreas G
AG
D000328:Adult; D000368:Aged; D001800:Blood Specimen Collection / Q000379:methods; D002648:Child; D002675:Child, Preschool; D002956:Citrulline / Q000097:blood*; D005260:Female; D006498:Hepatectomy; D006801:Humans; D007223:Infant; D007422:Intestines / Q000637:transplantation*; D016031:Liver Transplantation / Q000502:physiology; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods; D014184:Transplantation, Homologous / Q000502:physiology*
D002956:Citrulline