I am a medial technologist working at a large inter city hospital in
the Core Lab.  In Hematology, we are currently checking every MCV >105
by making a 1:3 dilution and then running again through our Hematology
analyzer to verify that it is not caused from rouleaux.  We are also
maintaining a card file of all our patients with MCVs >105 excepting
certain patients with explained increased MCVs.

I just downloaded and read the 2005 CAP requirement (HEM.30200-Phase I
Are red cell indices (MCV, MCH, MCHC) monitored routinely to detect
random errors?) that states "...Patient sample red cell indices
(Wintrobe indices or MCV, MCH, MCHC) should be monitored routinely to
detect random errors, instrument malfunction, or spurious
results...." *

Since we also always do RBC Morphology yearly on these patients by
reviewing peripheral smears on all MCVs > 105 wouldn't that be enough
to verify that we are not missing falsely increased MCVs?  I was
thinking that it would, and also educating everyone to make sure they
look for rouleaux in these cases.

Thanks,
Karen

*www.cap.org/apps/docs/laboratory_accreditation/checklists/hematology_coagulation
_october2005.doc
COMMISSION ON LABORATORY ACCREDITATION
Laboratory Accreditation Program
HEMATOLOGY - COAGULATION CHECKLIST
©2005. College of American Pathologists