Cytomegalovirus (CMV) infection is a major complication following solid organ transplantation resulting in significant morbidity and mortality. The guidelines published in 2004 have recommendations for therapy; however, the frequency of resistant CMV infection is increasing and therapy is not clearly defined. There are a few alternatives to ganciclovir such as foscarnet, cidofovir, and leflunomide; however, their use is limited by adverse effects. This report summarizes the successful use of high-dose ganciclovir for the treatment of a resistant CMV caused by UL97 mutation.

MRC-5 cultures treated with dexamethasone, dimethyl sulfoxide, and calcium were compared with untreated cultures and cultures treated with dexamethasone and dimethyl sulfoxide for the detection of human cytomegalovirus by the shell vial method. The addition of calcium resulted in significantly increased growth of human cytomegalovirus AD169. Protein studies and cell counts showed renewed cell proliferation in the treated cultures. When low-titer clinical specimens were retested, 27.5% of all positives revealed were found only on the vials treated with calcium. In a group of freshly tested specimens, the calcium-treated group accounted for 20% of the positives.

Optimum growth conditions for human cytomegalovirus (HCMV) include the use of subconfluent, actively growing cultures of human embryonic fibroblasts. Many clinical virology laboratories, however, use tissue culture cells from commercial sources. These cells are usually confluent, static cultures that tend to be less sensitive to viral infection. To determine whether dimethyl sulfoxide (DMSO) or dexamethasone (DEX), which are known enhancers of HCMV, facilitates the detection of the virus in confluent cells, we tested both HCMV AD169 and a number of clinical specimens suspected to contain HCMV on MRC-5 cells in both shell vials and conventional tube cultures. We found that, in the shell vial test, treatment of the cultures with either DMSO or DEX before and after inoculation increased the number of cells staining positive by threeto sixfold compared with untreated controls. Best results were obtained by pretreating the cultures with DEX alone and by treating the cultures with a combination of DEX and 1% DMSO postinfection. In the conventional MRC-5 culture tubes, treatment with the reagents resulted in the more rapid appearance of cytopathic effect and a more extensive infection of the cell sheet. The experimental findings indicate that the enhancing effect of DEX is attributable mainly to the increased production of a cellular mRNA during the period preceding viral infection.

Standard cell culture and centrifugation culture were compared for the isolation of varicella-zoster virus from 337 clinical specimens. Of a total of 85 (25%) positive specimens, 67 (78.8%) were positive by centrifugation culture alone and 18 (21.2%) were positive by both methods. When epithelial cells from the specimen were included in the vial inoculum, these cells stained positive and increased the varicella-zoster virus detection rate by 30%.

Treatment of MRC-5 cells with dexamethasone, dimethyl sulfoxide, or a combination of the two enhanced the detection of herpes simplex virus by threeto fourfold in these cells. Fluorescent plaques were noticeably larger on cover slips treated with the enhancing agents. Low-positive clinical specimens were stored and tested in parallel in treated and untreated shell vials, and 6 to 40%o of these stained positive in the treated cultures but not in the untreated controls. In standard tube cultures, cytopathic effect began earlier and was more extensive in treated tubes.