Sults are available within 24 hours. Despite good specificity (up to 99 percent), eia is reported to have only moderate and variable sensitivity (60 to 95 percent) . There is a relatively high false negative rate since c to k pg of toxin must be present for the test to be positive . buy viagra in usa online Up to three serial eia tests may increase the diagnostic yield by as much as 10 percent if the initial test is negative, although this incurs excessive cost without substantially enhancing diagnosis . viagra tablets online uk Some laboratories may favor adopting a policy limiting the number of specimens tested from a given patient during a one week period; in a review of 3749 initially negative tests, only 2. 5 percent were positive upon repeat testing within 10 days of the first test . Supplementing negative eia stools tests with tissue culture assay may also be useful. viagra going generic Polymerase chain reaction (pcr) — in 2009 the us food and drug administration approved three real-time pcr assays for the gene encoding toxin b (cepheid gene xpert), bd-geneohn c diff assay, and ivd rt-pcr (pro-gastro, prodesse). viagra cost These modalities are rapid, accurate diagnostic tools for c. Difficile, which is important for prompt implementation of treatment and infection control measures. In a study comparing the cepheid xpert c. Difficile assay with cell cytotoxicity neutralization for diagnosis of clostridium difficile infection, the sensitivity and specificity of the cepheid assay were 97 and 93 percent, respectively . viagra for sale Using the pcr ribotyping as a reference for the hypervirulent 027 strain, the corresponding figures were c and 98. cheap generic viagra 1 percent, respectively. A previous study compared pcr and enzyme immunoassay (eia) techniques with anaerobic culture (the "most sensitive") in 618 stool samples; sensitivity and specificity were better for pcr than eia (93 and 97 percent versus 73 and 97 percent, respectively) . viagra kaufen deutschland (see "epidemiology, microbiology, and pathophysiology of clostridium difficile infection in adults", section on 'hypervirulent strain'. cheap viagra online ) organism detection — organism detection assays include common antigen testing and anaerobic culture. An inherent problem with detection of the organism rather than the toxin is that not all c. nationalityinworldhistory.net/bsh-buy-viagra-online-no-prescription-xr/ Difficile strains are toxigenic and up to 30 percent of hospitalized patients are colonized without disease . In one study of hospitalized patients colonized with c. Difficile, 92 percent of patients with diarrhea were colonized with toxigenic strains, compared with 81 percent of asymptomatic carriers . viagra kaufen deutschland Some labor.