In all other cases in which a known
or suggestive etiologic agent was detected by PCR alone, the
presence of fungal filaments in direct microscopy would have
indicated at least that a mycosis was present. The five microscopy-negative, PCR-positive cases, though, mean that PCR
increased the number of confirmed mycoses in this study from
181, as would have been recognized in conventional studies, to
186, an increase of 2.8%. Though this may not seem a high
percentage, the high numbers of patients seeking relief from
onychomycosis must be kept in mind. Scher (43) showed that
in one year alone, 662,000 Americans over the age of 65 consulted a physician for handling of suspected onychomycosis. If
2.8% of this population were to have their mycosis missed on
the first examination, this would amount to 18,536 inade quately handled patients over 1 year in just that single demographic group.