COULTER STKS VS ABBOTT CELL-DYN-3500 FOR COUNTING LAMELLAR BODIES IN AMNIOTIC-FLUID

Lamellar body counts in human amniotic fluid assist in the prediction of fetal lung maturity and can be performed rapidly and inexpensively by using the platelet channel of a hematology analyzer. We compared tw o analyzers for enumerating lamellar bodies. We tested 100 fresh amnio tic fluid samples on both instruments. The lamellar body counts ranged from 3 to 364 x 10(3)/mu L (3-364 x 10(9)/L) on one analyzer and from 3 to 195 x 10(3)/mu L (3-195 x 10(9)/L) on the other. Statistical ana lysis showed excellent correlation (r = 0.99) yielding a regression eq uation of y = 3.91 + .467x. This analysis demonstrates that institutio ns will be faced with the challenge of establishing and incorporating instrument-specific lamellar body reporting protocols and reference ra nges that include the specific analyzer and method used.