"In vivo" kinetics of 99m-technetium labelled leucocytes in dogs and the effects of an abscess.

A new labelling method of blood white cells using "cold" pyrophosphate and 99m-technetium pertechnetate was assessed in 6 normal dogs and 6 dogs with turpentine induced abscesses (8). In normal dogs, blood kinetic studies showed a two component exponential disappearance pattern of the radioactivity, the late half-life being from 4 to 20 hours. Direct organ counting and external computer assisted gamma camera counting showed an immediate accumulation in the lungs followed by a progressive decrease. There is a marked uptake into the liver and spleen. In bearing abscesses dogs, there is an obvious increase in local radioactivity, in spite of a decreased local blood supply, allowing scintigraphic demonstration of such foci in a limb. However, the abscess model is far from perfect and further studies are required before there is a routine use in man for the detection of abscesses.