STUDIES OF ONE INVASIVE AND 2 NONINVASIVE METHODS FOR DETECTION OF BACTERIAL-CONTAMINATION OF PLATELET CONCENTRATES

Recently a new method for noninvasive detection of bacterial contamina tion of platelet concentrates was described [Arpi et al.: Vox Sang 199 3;65:335-336]. A CO2-sensitive label is applied on the outer surface o f the plastic container of the platelet concentrate. When any contamin ating bacteria have increased the pCO(2) to a certain level the label changes color, indicating bacterial growth. We have studied this techn ique and applied such sensitive labels both directly onto PCs and onto plastic bags with culture medium into which platelet contents have be en transferred. However, in both cases the sensitivity of the techniqu e was found insufficient for practical quality control of PCs. There s eem to be two problems with this principle: (1) platelets produce CO2 and (2) a considerable amount of the gas passes beside the detection l abel, in this way decreasing the sensitivity of detection by the label . This noninvasive technique was compared with an invasive method usin g automated bacterial culture, which was found sensitive and rapid.