ABSTRACT
BACKGROUND: We report on two allogeneic stem cell transplant recipients who developed cytomegalovirus disease associated with new viral mutations that conferred antiviral drug resistance. METHODS: Blood specimens obtained during symptomatic disease were analyzed for mutations in the CMV UL97 and DNA polymerase genes and new mutations were assessed by recombinant phenotyping. RESULTS: Rising cytomegalovirus (CMV) antigenemia occurred after 4-5 months of preemptive valganciclovir therapy, followed by symptomatic CMV disease including fatal pneumonia in one case. In one case, a new viral UL97 mutation (deletion of codons 601-603) was found which conferred 15-fold increased ganciclovir resistance. In the other case, a known UL97 resistance mutation M460V and a new DNA polymerase (pol) mutation D413A were found. D413A conferred ganciclovir and cidofovir resistance. CONCLUSIONS: Known and newly discovered drug resistance mutations arising during preemptive therapy may complicate post-transplant CMV disease in stem cell recipients. Improved recombinant phenotyping methods enable the rapid quantitation of the resistance conferred by newly identified UL97 and pol mutations.
Subject(s)
Antiviral Agents/therapeutic use , Cytomegalovirus Infections/virology , Cytomegalovirus/genetics , DNA-Directed DNA Polymerase/genetics , Drug Resistance, Viral/genetics , Ganciclovir/analogs & derivatives , Mutation , Phosphotransferases (Alcohol Group Acceptor)/genetics , Stem Cell Transplantation , Cytomegalovirus/drug effects , Cytomegalovirus/growth & development , Cytomegalovirus Infections/drug therapy , Cytomegalovirus Infections/prevention & control , Female , Ganciclovir/therapeutic use , Humans , Middle Aged , Transplantation, Homologous , ValganciclovirABSTRACT
We describe 4 patients with encephalitis due to possible reactivation of human herpesvirus 6 (HHV-6) infection who were enrolled in the California Encephalitis Project. All were immunocompetent and had HHV-6 loads determined in cerebrospinal fluid specimens. Tests for detection of HHV-6 should be considered for individuals with encephalitis.
Subject(s)
Encephalitis, Viral/virology , Herpesvirus 6, Human/isolation & purification , Roseolovirus Infections/diagnosis , Adolescent , Adult , Aged , Antiviral Agents/therapeutic use , Encephalitis, Viral/cerebrospinal fluid , Encephalitis, Viral/drug therapy , Female , Humans , Male , Polymerase Chain Reaction/methods , Roseolovirus Infections/cerebrospinal fluid , Roseolovirus Infections/drug therapy , Roseolovirus Infections/virology , Viral LoadABSTRACT
The Roche MagNA Pure automated nucleic acid extraction system was tested for its ability to extract Borrelia burgdorferi DNA from a diverse set of spiked specimen types including blood, cerebral spinal fluid, synovial fluid, urine and ticks. A method comparison between MagNA Pure automated extraction and manual extraction, using either QIAamp columns or phenol/chloroform extraction, showed equivalent detection sensitivities for all methodologies with all specimen types (except for urine, in which case QIAamp extraction was twofold less sensitive). Eighty positive clinical specimens (as determined by an independent testing method), including 76 synovial fluid, and 4 cerebral spinal fluid specimens, were found to be positive by the MagNA Pure/real-time PCR method of extraction and detection. This data shows that the MagNA Pure system can be used to extract B. burgdorferi DNA from clinical specimens, and when combined with real-time PCR, the result is an extremely sensitive assay with limited hands on time and rapid turn around times.