Detection of HCMV from clinical specimens was a slow process until the development of shell vial method with staining for immediate early antigen (IEA). Culture though still considered insensitive is widely used for other than blood samples. A method to improve culture sensitivity is desirable.TurboTreat™, a CMV pretreatment medium from Diagnostic Hybrids Inc., was evaluated on Mv1Lu, R-Mix and MRC-5 cells for improved sensitivity for HCMV detection.Monolayers of Mv1Lu, R-Mix and MRC-5 cells in 48-well plates were treated with TurboTreat™ for overnight (o/n), 4h or left untreated and then inoculated with previously positive HCMV specimens. After o/n incubation, cells were fixed, stained and positive cells counted.CMV TurboTreat™ enhanced detection 2–3-fold after 4h treatment and 4–6-fold after o/n treatment in Mv1Lu and R-Mix cells and to a lesser extend in MRC-5 cells with clinical isolates of HCMV. With frozen clinical specimens, Mv1Lu cells treated o/n, 4h or untreated detected 23, 21 and 15 positive specimens, respectively. R-Mix cells detected 19, 18, and 14 positives, respectively and MRC-5 cells detected 16, 15 and 15 positives, respectively. In no case was a positive detected in another cell line regardless of treatment that was not detected in Mv1Lu treated o/n.The o/n pretreatment with CMV TurboTreat™ on Mv1Lu cells is the optimum condition of treatment and significantly enhanced the detection of HCMV. Even 4h pretreatment of Mv1Lu cells showed significant enhancement over untreated Mv1Lu, R-Mix and MRC-5 cells. Pretreatment of Mv1Lu cells with CMV TurboTreat™ for 4h or longer increased the sensitivity of rapid HCMV detection.