Detection of IgM antibody to cytomegalovirus and rapid diagnosis of this virus infection by the shell vial assay.

Multiple serum specimens from 10 patients with known cytomegalovirus (CMV) infections and 498 sera consecutively submitted to the laboratory for the diagnosis of CMV infection were tested for anti-CMV IgM after treatment with goat anti-human IgG and QAE-Sephadex A50 column chromatography. Specimens from all 10 patients were positive for IgM after treatment with anti-IgG, but only 8 after the column procedure. Anti-CMV IgM was detected in 23 of 498 (4.6%) specimens pretreated with anti-IgG but in only 12 (2.4%) of these samples after the sera was passed through QAE-Sephadex A50 columns. Anti-CMV IgM was detected exclusively in 2 sera after QAE-Sephadex A50 column treatment (sensitivity, 83%) and in 13 specimens pretreated with anti-IgG sera (specificity, 97%). Serology (IgG and IgM) was compared with the shell vial cell culture assay and histology for providing the first evidence of CMV infection in 28 liver transplant patients. CMV infection was detected initially by the rapid shell vial assay (24) or histology (3) in 27 (96%) of these patients. Detection of anti-CMV IgM in these patients had little value for rapid diagnosis of these infections, and suggests that serology should be recommended mainly for the diagnosis of primary CMV infections in localities in which the rapid shell vial assay is not available.