AN INCREASE IN THE NUMBER OF POLYMORPHONUCLEAR LEUKOCYTES INOCULATED ON SHELL-VIAL CULTURE INCREASES THE SENSITIVITY OF THIS ASSAY IN THE DETECTION OF CYTOMEGALOVIRUS IN THE BLOOD OF IMMUNOCOMPROMISED PATIENTS

A prospective study mas conducted comparing the sensitivity of the pp6 5 antigenemia assay (AGA) to that of the shell-vial culture (SVC) inoc ulated with increasing quantities polymorphonuclear leukocytes (PMNLs) in the detection of cytomegalovirus (CMV) in peripheral blood. From t he cellular sits pension, three SVCs were inoculated with 200,000, 400 ,000, and 800,000 PMNLs, Respectively. Of the 201 patients studied, 67 (31.9%) had positive results in one of the two analytic tests (AGA or SVC). In this group, 13 (19.4%) presented a negative AGA assay; 13 (1 9.4%) an AGA of 1; 13 (19.4%) an AGA of between 2 nl and 5; and 28 (41 .8%) an AGA with ii value >6 PMNL-positive x 100,000 PMNLs. The SVC in oculated with 200,000 PMNLs detected the presence of CMV in 42 cases ( 62.6%); 55 (82%) with 400,000; and 64 (95.5%) with 800,000. Statistica lly significant differences were observed between the isolation capaci ties of the SVC inoculated with 200,000 and 400,000, and the SVC inocu lated with 800,000 PMNLs (p = 0.0001). In the comparison of the overal l sensitivity of the AGA with that of the SVC with 200,000, the AGA wa s found to be significantly more sensitive (p = 0.0052). When comparin g with the SVC with 400,000 PMNLs, the two techniques were found to be equally sensitive; and in the comparison? with the SVC with 800,000, the culture displayed a greater detection sensitivity (p = 0.0023). Ac cording to these results, ii seems evident that the increase in the ab solute number of PMNLs inoculated in the SVC leads to a significant in crease in the sensitivity of the SVC in the detection of low-level vir emia by CMV. (C) 1998 Elsevier Science Inc.