Transfusion
Because acute virus infections are sensitively indicated by increased
neopterin concentration, screening for elevated neopterin concentrations in
blood donations allows to reduce risk of infections.
Serum neopterin determination for
the additional safeguarding of blood transfusions. Our experiences with
76,587 blood donors.
Hoenlinger M, et al. Central Institute for Blood Transfusion, University Clinic Innsbruck,
Innsbruck, Austria
(Dtsch Med
Wochenschr 1989; 114: 172-176)
Since October 1986, all volunteer blood donors in the Tirol of Austria have
been tested for neopterin. Serum neopterin levels were raised in 1242
donors (1.6%), 650 of whom (52.3%) consented to another test four weeks
after the donation. In retrospect, 148 of these donors (22.8%) had an
illness or abnormal symptoms at the time of donation or within a few days
of it: according to the "guidelines for blood group testing and blood
transfusion" of the Federal German Chamber of Doctors (Deutsche
Bundesarztekammer) 25 of these (16.9%) should be permanently excluded as
blood donors. The other 123 donors would have been temporarily excluded,
according to the guidelines, if their illness had been known at the time of
donation. Since the beginning of 1988, all donated blood with increased
serum neopterin levels also had an IgM test for cytomegalovirus (CMV): nine
of 243 samples tested (3.7%) indicated an acute CMV infection. The
neopterin assay thus detects a variety of potentially harmful diseases or
conditions which would not be revealed by the usually employed battery of
routine tests.
Acute cytomegalovirus infections in
blood donors are indicated by increased serum neopterin concentrations.
Schennach H, et al. Central Institute for Blood Transfusion, University Clinic Innsbruck,
Innsbruck, Austria
(Med
Microbiol Immunol 2002; 191: 115-118)
In Austria serum neopterin measurement was introduced as an additional
unspecific screening marker for the detection of routinely unscreened viral
infections in blood donations in 1994. This study was performed to test for
associations between serum neopterin concentrations in blood donations and
cytomegalovirus infections of the donors. All consecutive blood donations
from volunteer blood donors collected during 1 year were incorporated into
the study. Serum neopterin concentrations were measured by enzyme-linked
immunosorbent assay (ELISA), and each donation of donors with CMV
seronegativity or unknown CMV status was also screened for CMV antibodies
by CMV IgG/IgM antibody ELISA. Data of donors who had two or more donations
within this period were retrospectively analyzed for CMV seroconversions.
CMV seroconversion was defined as a change in the donor's CMV status from
antibody negative to positive. Frozen, stored plasma samples of the
matching donors were tested for CMV IgM antibodies to confirm
seroconversion. CMV seroconversions were classified by antibody patterns.
In total, 56,068 consecutive blood donations were given by 44,427 volunteer
donors. Among these, 9,105 had more than one donation during the
observation period, and 4,329 (47.5%) out of these repeated donors were
initially CMV antibody negative, of whom 36 were recruited as candidates
for CMV seroconversion; 20 conversions were confirmed. All early infections
( n=8) were associated with neopterin concentrations of more than 13 nmol/l
(98th percentile of all donations = 12.1 nmol/l) and all donations were
excluded from transfusion solely on the basis of their elevated neopterin
level. In addition, 17% of late and carrier states ( n=12) showed elevated
neopterin concentrations. Acute CMV infections among blood donors presented
with elevated serum neopterin concentrations even before CMV IgG/IgM
antibodies were detectable.
Human parvovirus Bb19 detection in
asymptomatic blood donors: association with increased neopterin
concentrations.
Schennach H, et al. Central Institute for Blood Transfusion, University Clinic Innsbruck,
Innsbruck, Austria
(J Infect Dis 2002; 186: 1494-1497)
Serum neopterin concentrations were determined in 20,000 blood donations.
For the 400 donations with neopterin concentrations above the 98 th
percentile and another 1200 donations with neopterin concentrations in the
lower range, results of human parvovirus (HPV) B19 tests were compared.
Infectious specimens were identified by dot blot hybridization assay and
polymerase chain reaction (PCR) that used the outer primers and detected 1
pg of HPV B19 DNA, corresponding to approximately 10(5) copies of the
genome, in the specimens and by a nested PCR that detected 1-10 fg of DNA,
corresponding to 10(2)-10(3) copies of the genome. Of 400 specimens with
neopterin concentrations > or =12 nmol/L (98th percentile, current
cutoff), 10 tested positive by dot blot hybridization assay (9 of these
were confirmed by nested PCR). Among 1200 specimens with low neopterin
concentrations (<12 nmol/L), no specimen containing HPV B19 DNA was
detected. These findings suggest an association between elevated neopterin
concentrations and HPV B19 infectivity.