Lamellar body counts for rapid fetal lung maturity testing.
OBJECTIVE
To evaluate amniotic fluid lamellar body counting as a fetal lung maturity test. Lamellar body particles can be rapidly counted using the platelet channel of most blood cell analyzers.


METHODS
We conducted a 3-year prospective clinical outcome study. During the interval under study, outcomes of 247 neonates were used to evaluate the test; 28 neonates developed respiratory distress syndrome (RDS). Lecithin-sphingomyelin ratio (L/S) was available for 187 cases.


RESULTS
All cases of RDS had lamellar body counts of 55,000/microL or less and L/S of 2.2 or less; 59% of cases with no RDS had counts greater than 55,000/microL and 70% of normal cases had L/S higher than 2.2.


CONCLUSIONS
Use of lamellar body counts is justified as a rapid screening test to predict fetal lung maturity. Immature results should be followed by a more specific test such as L/S.
Ashwood
E R
ER
Department of Pathology, University of Utah School of Medicine, Salt Lake City.
Palmer
S E
SE
Taylor
J S
JS
Pingree
S S
SS
D000653:Amniotic Fluid / Q000737:chemistry*; D003584:Cytological Techniques; D005325:Fetal Organ Maturity / Q000502:physiology; D006801:Humans; D007231:Infant, Newborn; D008168:Lung / Q000196:embryology*; D010713:Phosphatidylcholines / Q000032:analysis; D011446:Prospective Studies; D011663:Pulmonary Surfactants / Q000032:analysis*; D012680:Sensitivity and Specificity; D013109:Sphingomyelins / Q000032:analysis
D010713:Phosphatidylcholines; D011663:Pulmonary Surfactants; D013109:Sphingomyelins