Vol 6, No 2 (2003)
Published online: 2003-10-10
Diagnostic sensitivity of two radio receptor assays (TRAK Assay and TRAK Dyno Human) for detection of TSH receptor antibodies
Nucl. Med. Rev 2003;6(2):119-122.
Abstract
Radio receptor assays for the detection of TSH receptor antibodies
in serum are typically based on binding the competition
of TSH-R antibodies and 125I “labeled” TSH for membrane preparation
of thyrocytes (TBII tests). The sensitivity of the available
tests utilizing porcine cell membranes was found to be around
80%. A new test (TRAK Dyno human, BRAHMS) utilizes human
recombinant TSH receptor and human standard material that
is supposed to improve the performance of the test. We have
compared the results of these two assays. The sensitivity of the
TRAK Assay tested in 356 patients with untreated Graves’ disease
was found to be 85%, and 97.5% for TRAK Dyno human in
111 newly diagnosed patients. Both tests were performed from
the same serum specimen for 60 of the investigated patients.
The TRAK Assay was positive in 50 patients (83.2%) and TRAK
Dyno human in 59 patients (98.3%). The specificity of the new
radio receptor assay was also improved.
Keywords: radioreceptor assayhuman receptorTSH receptor antibodyGraves’ disease