Detection of CMV in urine: comparison between DNA-DNA hybridization, virus isolation, and immunoelectron microscopy

Urinary cytomegalovirus excretion: The unresolved issues

Cytomegalovirus (CMV) excretion in urine is frequently observed in clinical practice. However, the specific circumstances and pathophysiological mechanisms underlying this shedding remain largely unknown. Here, we address some of the key questions regarding urinary CMV excretion, focusing on new hypotheses raised by recent advances in the field. Cellular origins of CMV shedding, clinical contexts of occurrence, systemic spread of the virus versus compartmentalization in the urinary tract, and clinical impact are successively discussed.

Human cytomegalovirus-viruria in hematopoietic stem cell transplant recipients: Context and impact

BACKGROUND

Episodes of CMV-viruria have been reported in hematopoietic stem cell transplant (HSCT) recipients, but their context of occurrence, pathophysiology, and clinical significance remain misunderstood.

METHODS

Uurine samples from 517 recipients were collected. Clinical features of recipients with or without episodes of CMV-viruria were retrospectively compared.

RESULTS

CMV-viruria was detected in 15.5 % of cases. Age, sex, type of transplantation, HLA-matching, conditioning regimen, and immunosuppressive therapies did not differ between patients with and without CMV-viruria. CMV-seropositive status (R + ) was more frequent among CMV-viruric recipients. Cumulated mortality did not differ between the two groups but graft-versus-host diseases occurred more frequently among CMV-viruric patients (p = 0.04). No reduction of the estimated glomerular filtration rates was observed in CMV-viruric recipients.

CONCLUSIONS

CMV-viruria primarily occurs in CMV-seropositive recipients and is not related to the degree of immunosuppression. We suggest that CMV-viruria is primarily related to the inability of the graft immune system to contain CMV-replication in R + patients. CMV-viruria is not associated with increased mortality or renal dysfunction.

Detection of cytomegalovirus by dot-blot DNA hybridization using probes labelled with 32P by nick translation or random hexanucleotide priming

A DNA hybridization assay for the detection of human cytomegalovirus (HCMV) DNA was developed using random hexanucleotide-primed 32P-labelled Hind III restriction fragments of HCMV DNA as probes, and compared with a DNA hybridization assay using probes labelled with 32P by nick translation. Nick-translated probes were shown to be able to detect between 1 and 10 pg of homologous DNA or the DNA of 10-50 HCMV-infected fibroblasts. Random hexanucleotide-primed DNA probes lowered these detection limits to 0.1-0.5 pg of homologous DNA or one to five HCMV-infected fibroblasts. An increase in the autoradiographic exposure time from 18 h to 4 days increased the level of detection for homologous DNA or HCMV-infected fibroblast DNA by approximately five-fold. Preliminary screening of 35 urine samples by DNA hybridization using a random hexanucleotide-primed probe correctly identified three samples positive by virus isolation in tissue culture or immediate-early nuclear antigen detection and 29 of 32 samples negative by tissue culture.