Kidney allograft pathology assessment has been traditionally
based on clinical and histological criteria. Despite improvements
in Banff histological classification, the diagnostics in particular
cases is problematic reflecting a complex pathogenesis of graft
injuries. With the advent of molecular techniques, polymerasechain reaction, oligo- and microarray technologies allowed to
study molecular phenotypes of graft injuries, especially acute and
chronic rejections. Moreover, development of the molecular
microscope diagnostic system (MMDx) to assess kidney graft
biopsies represents the first clinical application of a microarraybased method in transplantation. Whether MMDx may replace
conventional pathology is the subject of ongoing research,
however this platform is particularly useful in complex histological
findings and may help clinicians to guide the therapy.