[76Br]Bromodeoxyuridine PET in tumor-bearing animals.

5-bromodeoxyuridine (BUdR) provides in vitro measures of tumor cell proliferation. We used positron emission tomography to study tissue and plasma kinetics of [76Br]BUdR in tumor-bearing animals. In order to account for the slow washout of the major plasma metabolite, [76Br]bromide, a mathematical correction for the distribution volume of [76Br]bromide was applied. However, following correction specific tumor tracer retention was low or even zero and did not correlate with independent measures of proliferation. The kinetic characteristics of [76Br]BUdR make this tracer unsuitable for proliferation imaging.

Bromide kinetics and distribution in the rat. II. Distribution of bromide in the body.

The distribution of 82Br-bromide in 15 different organs and tissues of rats has been determined by high-resolution gamma-ray spectrometry and by the scintillation counting technique at different times after the application of Na 82Br, either by subcutaneous injection or by continuous administration in the drinking water. The amount of 82Br-bromide in the various tissues reached its largest uptake within a few hours, and the concentration ratio of 82Br in the tissues to blood remained practically constant between 8 and 396 h after the application. The whole stomach of rats was the only organ of those investigated that had a larger uptake of 82Br than blood. Contrary to some previous findings, the concentration of radiobromide in the thyroid was found not to exceed that in the blood. A remarkably high concentration of 82Br was found in the skin, which represented, because of its large mass, the most abundant depot of bromide in the body of rats. The demonstrated excretion of bromide was mainly renal, at a rate of approximately 5% of the administered dose per 24 h.

The use of the bromine partition test in the diagnosis and prognosis of tuberculous meningitis.

The bromine partition test was successfully used to differentiate cases of proven tuberculous meningitis from patients with aseptic and non-tuberculous meningitis. Forty patients, 22 males and 18 females aged 5 to 30 years (mean 13.5 +/- 6.2), were included in the study. Nineteen patients were confirmed to have tuberculous meningitis, 12 had aseptic meningitis, and 9 bacterial meningitis. All patients received 0.6 mci/kg of bromine 82 administered through a nasogastric tube as ammonium bromide dissolved in 5 ml of isotonic sodium chloride. The serum to CSF bromine ratio was then calculated 48 hours after the dose. The test was then repeated 8 days later in patients with bacterial meningitis and 8, 90, and 180 day later in patients with tuberculous meningitis. The test was very useful in quickly differentiating cases of aseptic from bacterial and tuberculous meningitis and was also a useful prognosticator in patients with severe tuberculous meningitis.