Lamellar Body Phospholipid Content of Amniotic Fluid: A Possible Index of Fetal Lung Maturity

Abstract A micro-method has been devised for isolating a lung-derived membranous fraction from human amniotic fluid. The phospholipid content of this fraction, known as lamellar body phospholipid, provides an indication of fetal lung maturity (Ann. Clin. Biochem 16: 191, 1979). This method has now been applied to 479 samples of amniotic fluid from 330 pregnancies. The lecithin/sphingomyelin ratio has also been determined for each of the samples by the routine method currently in use in the hospitals providing the samples. Hyaline membrane disease was associated with a low concentration of lamellar body phospholipid (< 35 mg/L) in all eight cases encountered in this study. In contrast, in 182 of the 185 cases where the lamellar body content of the amniotic fluid, collected within two days of delivery, exceeded 35 mg/L, the infants were free from serious respiratory problems. Data are presented which suggests that the lecithin/sphingomyelin ratio falsely indicated lung immaturity in many cases, amounting to 44% or more of all values indicating immaturity that were reported.

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Lamellar body phospholipid content of amniotic fluid and L/S ratio compared in assessing fetal lung maturity.

Clinical Chemistry ◽

10.1093/clinchem/26.6.0766 ◽

1980 ◽

Vol 26 (6) ◽

pp. 766-769

Author(s):

C G Duck-Chong ◽

J M Gupta ◽

G N Storey ◽

C R Houghton

Keyword(s):

Amniotic Fluid ◽

Lamellar Body ◽

Fetal Lung ◽

Hyaline Membrane Disease ◽

Phospholipid Content ◽

Human Amniotic Fluid ◽

Respiratory Problems ◽

Fetal Lung Maturity ◽

Hyaline Membrane ◽

Lung Maturity

Abstract A micro-method has been devised for isolating a lung-derived membranous fraction from human amniotic fluid. The phospholipid content of this fraction, known as lamellar body phospholipid, provides an indication of fetal lung maturity (Ann. Clin. Biochem 16: 191, 1979). This method has now been applied to 479 samples of amniotic fluid from 330 pregnancies. The lecithin/sphingomyelin ratio has also been determined for each of the samples by the routine method currently in use in the hospitals providing the samples. Hyaline membrane disease was associated with a low concentration of lamellar body phospholipid (< 35 mg/L) in all eight cases encountered in this study. In contrast, in 182 of the 185 cases where the lamellar body content of the amniotic fluid, collected within two days of delivery, exceeded 35 mg/L, the infants were free from serious respiratory problems. Data are presented which suggests that the lecithin/sphingomyelin ratio falsely indicated lung immaturity in many cases, amounting to 44% or more of all values indicating immaturity that were reported.

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Lamellar body count in amniotic fluid for assessing fetal lung maturity

Medicinski pregled ◽

10.2298/mpns1010595v ◽

2010 ◽

Vol 63 (9-10) ◽

pp. 595-600 ◽

Cited By ~ 3

Author(s):

Jovana Visnjevac ◽

Aleksandra Novakov-Mikic ◽

Aleksandra Nikolic ◽

Nemanja Visnjevac

Keyword(s):

Amniotic Fluid ◽

Screening Test ◽

Lamellar Body ◽

Roc Curves ◽

Fetal Lung ◽

Prospective Clinical Study ◽

Lamellar Bodies ◽

Fetal Lung Maturity ◽

Lung Maturity ◽

Body Count

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.

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Characterization of amniotic fluid lamellar bodies by resistive-pulse counting: relationship to measures of fetal lung maturity.

Clinical Chemistry ◽

10.1093/clinchem/35.4.612 ◽

1989 ◽

Vol 35 (4) ◽

pp. 612-616 ◽

Cited By ~ 35

Author(s):

S B Dubin

Keyword(s):

Amniotic Fluid ◽

Lamellar Body ◽

Fetal Lung ◽

Body Volume ◽

Number Density ◽

Lamellar Bodies ◽

Pulse Counting ◽

Fetal Lung Maturity ◽

Resistive Pulse ◽

Lung Maturity

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.

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Lamellar Body Count With Cell Dyn Emerald And Cell Dyn Ruby Methods On Preterm Birth

Journal Of Vocational Health Studies ◽

10.20473/jvhs.v1.i1.2017.7-10 ◽

2017 ◽

Vol 1 (1) ◽

pp. 7

Author(s):

Erlinda Widyastuti ◽

Ario Imandiri

Keyword(s):

Preterm Birth ◽

Amniotic Fluid ◽

Lamellar Body ◽

Fetal Lung ◽

Impedance Method ◽

Lamellar Bodies ◽

Cross Sectional ◽

Fetal Lung Maturity ◽

Lung Maturity ◽

Body Count

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).

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Aberrant lamellar body counts noted on the Beckman Coulter Unicel DxH 800

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2012-0026 ◽

2012 ◽

Vol 50 (9) ◽

Author(s):

Patrick B. Kyle ◽

Thomas J. Lawrence

Keyword(s):

Quality Control ◽

Amniotic Fluid ◽

Proficiency Test ◽

Lamellar Body ◽

Fetal Lung ◽

Lamellar Bodies ◽

Fetal Lung Maturity ◽

Target Values ◽

Quality Control Materials ◽

Lung Maturity

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.

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Comparative analysis of amniotic fluid lamellar body count and foam stability test as indices of fetal lung maturity

Medicinski pregled ◽

10.2298/mpns1012747v ◽

2010 ◽

Vol 63 (11-12) ◽

pp. 747-752 ◽

Cited By ~ 2

Author(s):

Jovana Visnjevac ◽

Aleksandra Novakov-Mikic ◽

Aleksandra Nikolic ◽

Nemanja Visnjevac

Keyword(s):

Respiratory Distress Syndrome ◽

Respiratory Distress ◽

Amniotic Fluid ◽

Distress Syndrome ◽

Lamellar Body ◽

Fetal Lung ◽

Receiver Operating Characteristic Curves ◽

Fetal Lung Maturity ◽

Lung Maturity ◽

Body Count

Introduction. Respiratory distress syndrome of the newborn caused by the fetal lung immaturity is a very serious clinical problem. Different tests of prenatal analysis of amniotic fluid, such as lamellar body count and Clements? test, are available for predicting the fetal lung maturity. Material and methods. A prospective clinical study was conducted on amniotic fluid samples from 2005 to 2006. The amniotic fluid samples were obtained at the gestational age of 30 to 42 weeks and collected by vaginal amniotomy, amniotomy during Caesarean section and 72 hours before the delivery by amniocentesis. A haematology analyzer (Nikon-Kohden?) was used to determine the lamellar body counts. Clements? test involved adding an equal volume of 96% ethanol to the multiple amniotic fluid volume (1:2, 1:4, 1:16, 1:32), followed by shaking and noting the presence of ring of bubbles. After the delivery, we compared the lamellar body count results and Clements? test and the outcome of pregnancies, primarily the development of respiratory distress syndrome. The most specific lamellar body cutoffs for maturity and immaturity were determined according to receiver operating characteristic curves. Results and Discussion. Out of 232 amniotic fluid samples which were tested, 112 samples were collected after vaginal amniotomy, 88 during the Caesarean delivery and 32 samples by amniocentesis. The overall incidence of respiratory distress syndrome was 14.6%. Receiver operating characteristic curves were used to identify cutoff points for the test. We found that both tests are good screening tests for predicting the fetal lung maturity with the area under the curve of 0.782 in Clements? test and 0.751 in the lamellar body count. Clements? cutoff 2 with sensitivity of 67.6% and specificity of 72.2%, proved best in the prediction of the fetal lung maturity. The lamellar body count cutoff of 42x10?/?l had the sensitivity of 82.4% and specificity of 64.6% in predicting the fetal lung maturity. Conclusion. Although both tests are good in predicting the fetal lung maturity, the lamellar body count has more advantages, because it is not only more objective, but also inexpensive, easy and fast to do, requires a small sample volume and is universally available.

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