Amniotic Fluid Lamellar Bodies Count as a Predictor of Fetal Lung Maturity in High Risk Pregnancy

2013 ◽  
Vol 64 (7-9) ◽  
pp. 553-562
Author(s):  
Hani M. Abd El-Aal ◽  
Mohamed F. Abbas ◽  
Abd El-Fattah M. El-Senity ◽  
Gaber Rezk ◽  
Abd El-Aleem El Gendy
Author(s):  
Coral G. Duck-Chong

Lamellar bodies, produced by secretory cells in the alveolar epithelium, are the major source of surfactant phospholipid. As the fetal lung matures, the membranous content of the lamellar bodies is secreted into the alveolar spaces and passes into the amniotic fluid, from which it can be isolated in a morphologically recognisable form. A method is described for the rapid isolation of a lamellar body fraction from amniotic fluid using a small air-driven clinical ultracentrifuge. The lamellar body phospholipid content of amniotic fluid increases towards the end of gestation, but the time of onset and the rate of this increase show wide individual variation. Preliminary results suggest that the lamellar body phospholipid content of amniotic fluid may be a useful index of fetal lung maturity.


2010 ◽  
Vol 63 (9-10) ◽  
pp. 595-600 ◽  
Author(s):  
Jovana Visnjevac ◽  
Aleksandra Novakov-Mikic ◽  
Aleksandra Nikolic ◽  
Nemanja Visnjevac

Introduction. Respiratory distress syndrome (RDS) of the newborn infant caused by immaturity of fetal lung is a very serious clinical problem. Surfactant is stored in the form of lamellar bodies. They are secreted into alveolar space and passed into amniotic fluid where they can be found. The similarity of lamellar body size to platelet size permits the use of a standard automated hematologic cell counter to estimate the number of lamellar bodies in amniotic fluid. Material and Methods. We conducted a prospective clinical study from 2005 - 2006 on amniotic fluid samples. Amniotic fluid samples were collected near delivery by transvaginal amniotomy, amniotomy during Cesarean section and 72 hours before delivery by amniocentesis. A hematology analyzer (Nikon - Kohden?) was used to determine the lamellar body counts. After birth of newborns we compared their complete clinical examination results particularly emphasizing the prediction of the method of RDS by lamellar body count. Maximally specific lamellar body cutoffs for maturity and immaturity were determined using ROC curves. Results and Discussion. Of 232 amniotic fluid samples which were tested, 112 samples were collected by transvaginal amniotomy, 88 were taken during Cesarean delivery and 32 samples were collected by amniocentesis. The incidence of RDS was 14.6%. ROC curves were used to identify cut points for the test. We found that LBC is a good screening test for predicting fetal lung maturity with the area under the curve of 0.751. LBC cutoff of 42x10?/?l, with sensitivity of 82.4% and specificity of 64.6%, proved best for predicting fetal lung maturity. Conclusion. LBC is a good screening test for predicting fetal lung maturity. The advantages of LBC are speed, objectivity, low price, low sample volume required and universal availability.


1989 ◽  
Vol 35 (4) ◽  
pp. 612-616 ◽  
Author(s):  
S B Dubin

Abstract Resistive-pulse counting studies of amniotic fluid lamellar bodies are presented and demonstrate a strong concordance with the predictions of accepted measures of fetal lung maturity. Uncentrifuged as well as centrifuged specimens could be evaluated, because cells and debris are rejected electronically. The technique is not affected by bilirubin or debris of lysed whole blood, and only mildly by meconium. Lamellar body number density and mean lamellar body volume were determined for 161 uncentrifuged and 241 centrifuged specimens. Number density maturity criteria (40,000/microL and 26,000/microL, respectively) were shown to be highly concordant with established measures of fetal lung maturity; mean lamellar body volume did not extend this concordance. Since electronic cell counters are generally available 24 h per day and the approach requires neither centrifugation nor subjective interpretation and is rapid and inexpensive, it is proposed that determining lamellar body number density by resistive-pulse counting may be a useful initial screen for the assessment of fetal lung maturity.


2017 ◽  
Vol 1 (1) ◽  
pp. 7
Author(s):  
Erlinda Widyastuti ◽  
Ario Imandiri

Background: Lamellar bodies are produced by pneumocyte type II cells in the lung alveoli. Lamellar bodies are present in amniotic fluid in increasing quantities as gestation advances, 1 – 5 µm in size, similar in size to small platelets and can be counted on most electronic cell counters in hematology analyzer. Lamellar body count is useful for prediction of fetal lung maturity and neonatal respiratory distress syndrome. The current gold standard for determination of fetal lung maturity is the evaluation of phospholipids in amniotic fluid samples by thin-layer chromatography, but it is time-consuming and not continuously available at most institutions. In this study we compare Cell Dyn Emerald and Cell Dyn Ruby method, which is expected to be a review for lamellar body count method. Purpose:  The aim of this study was to analyze lamellar body count with Cell Dyn Emerald and Cell Dyn Ruby method on preterm birth. Methods : This was a cross sectional study. Thirty three samples study were inpatient’s amniotic fluid with premature rupture of membranes in Obstetry and Gynecology ward emergency room Dr. Soetomo Hospital Surabaya. Lamellar body count was counted with Cell Dyn emerald and Cell Dyn Ruby method. The statistical differences were assessed using the ANOVA test . Results : The results showed significant differences (t=49,04), lamellar body count with Cell Dyn Ruby method was much lower than Cell  Dyn Emerald method. The lowest result with Cell Dyn Ruby method was 3.38 x 103/µL and 17 x 103/ µL with Cell Dyn Emerald method. The highest results with Cell Dyn Ruby method was 98,2 x 103/ µL and 221 x 103/ µL with Cell Dyn Emerald method. Conclusion : Lamellar body count with impedance method (Cell Dyn Emerald) is significantly higher than optic method (Cell Dyn Ruby).


Author(s):  
Patrick B. Kyle ◽  
Thomas J. Lawrence

AbstractThe lamellar body count (LBC) plays a crucial role in fetal lung maturity testing. Lamellar bodies are often counted in the platelet channel of routine hematology analyzers, resulting in a rapid and inexpensive assay for fetal lung maturity. Recently, significant imprecision was noted during LBC validation on the Beckman Coulter Unicel DxH 800.The results of two Beckman Coulter Unicel DxH 800 instruments were compared to those of a Coulter LH 750 and Coulter LH 500. Three pools of amniotic fluid, commercial quality control materials, and proficiency test specimens were analyzed on all four instruments. Fifty patient specimens were also analyzed using the Coulter LH 500 and the Unicel DxH 800.The mean values and precision obtained from commercial quality control materials and proficiency test samples were comparable on all four instruments. However, many erroneously low LBC results were produced from amniotic fluid pools using both DxH 800 instruments. The erroneous values were approximately 50% lower than respective target values, occurred randomly, and affected the low, medium, and high LBC results. Inter-assay precision of the three pools ranged from 24.7 to 39.0 CV% on the DxH 800 instruments.The source of LBC errors likely involves the exclusion of smaller lamellar bodies from the counts. The DxH 800 combines new data fusion technology and mathematical algorithms to produce increased accuracy and flagging efficiency. Laboratorians should be aware that the improved specificity of the DxH 800 may preclude its use for this laboratory-developed test.


1981 ◽  
Vol 27 (2) ◽  
pp. 239-242 ◽  
Author(s):  
M Y Tsai ◽  
M Cain ◽  
M W Josephson

Abstract We describe an indirect test of fetal lung maturity: the quantitation of disaturated phosphatidylcholine in amniotic fluid. The lipids in samples of amniotic fluid from 172 patients were reacted with osmium tetroxide, and disaturated phosphatidylcholine was then isolated by thin-layer chromatography. Interfering substances were retained by a pre-adsorbent layer. The charred disaturated phosphatidylcholine, quantitated by densitometry, was compared to standard dipalmitoyl phosphatidylcholine. Both within-run and between-run coefficients of variation were about 10%. Blood and meconium do not interfere. Six infants developed respiratory distress when disaturated phosphatidylcholine concentrations of amniotic fluid drawn within 72 h of delivery were less than 5.5 mg/L. A concurrently determined lecithin/sphingomyelin ratio falsely predicted lung maturity in one of these. In seven other samples for which lecithin/sphingomyelin ratios suggested lung immaturity but disaturated phosphatidyl-choline predicted maturity, none of the infants developed respiratory distress. In normal pregnancies, measurement of disaturated phosphatidylcholine in amniotic fluid appears to be a better predictor of fetal lung maturity than is measurement of the lecithin/sphingomyelin ratio. Further studies are needed to determine if this analysis is a better predictor in diabetic pregnancies.


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