Amniotic Fluid Lamellar Body Count Research Articles

Lysophosphatidylcholine acyltransferase 1 protein is present in maternal blood in the third trimester and is upregulated by antenatal corticosteroids.

Lysophosphatidylcholine acyltransferase 1 (LPCAT1) is involved in the production of fetal lung surfactant. We have shown that LPCAT1 mRNA is present in amniotic fluid and maternal plasma and that its quantity correlates with the amniotic fluid lamellar body count. The purpose of the present study was to assay maternal plasma for the LPCAT1 protein in term and preterm pregnancies; and to measure the impact of antenatal corticosteroids. Maternal and newborn plasma samples were obtained from 7 women admitted to the hospital for induction of labor. Maternal plasma was also obtained before administration of corticosteroids and 24h after thesecond dose of corticosteroids from 12 women with premature labor and premature rupture of membranes. After sample preparation, LPCAT1 protein levels were determined using sandwich ELISA. We discovered LPCAT1 protein in maternal plasma in measurable quantities after 32weeks gestation. Further, there was a rise of maternal plasma LPCAT1 in response to the clinical administration of antenatal corticosteroids. Quantitation of maternal plasma LPCAT1 protein offers promise in the ongoing study of fetal lung maturation.

Comparison between Amniotic Fluid Lamellar Body Count and Fetal Pulmonary Artery Doppler Indices in Predicting Fetal Lung Maturity in Cases of PPROM

Comparison between Amniotic Fluid Lamellar Body Count and Fetal Pulmonary Artery Doppler Indices in Predicting Fetal Lung Maturity in Cases of PPROM

Lamellar body count: Marker for foetal lung maturation promoted by intra-amniotic infection and/or inflammation

ObjectiveThere is evidence indicating that the risk of respiratory distress syndrome is reduced in preterm neonates exposed to intra-amniotic infection and/or inflammation. We hypothesised that foetal lung maturation promoted by intra-amniotic infection and/or inflammation results in elevated lamellar body count (LBC) in amniotic fluid (AF). This study aimed to determine the relationship between LBC in AF and intra-amniotic infection and/or inflammation in patients with threatened preterm birth. Study designThis was a retrospective cohort study of patients with threatened preterm birth. A total of 104 consecutive pregnant women underwent amniocentesis in the early preterm period [gestational age < 34 weeks] to evaluate intra-amniotic infection and/or inflammation and foetal lung maturity. Intra-amniotic infection was confirmed by positive AF culture results for aerobic/anaerobic bacteria, fungi, and genital mycoplasma. Intra-amniotic inflammation was defined as a positive AF matrix metalloproteinase-8 rapid test. Outcomes of the study population were compared according to LBC in AF using a cut-off of 15,000/mm3. ResultsThe rates of elevated LBC and intra-amniotic infection and/or inflammation were 23% (24/104) and 52% (54/104), respectively. The median LBC was significantly higher in patients with intra-amniotic infection and/or inflammation than in those without [median LBC, 9,000/mm3 (interquartile range, IQR: 3,000–39,000) vs. 3,000/mm3 (IQR: 2,750–5,000), p < 0.001]. Intra-amniotic infection and/or inflammation was observed in 96% (23/24) of patients with elevated LBC and 39% (31/80) of patients without elevated LBC (p < 0.001). On multivariable analysis, the presence of intra-amniotic infection and/or inflammation was significantly associated with elevated LBC with an odds ratio (OR) of 66.0 [95% confidence interval (CI) 6.6–664.4, p < 0.001], even after accounting for gestational age at amniocentesis being a significantly related factor for predicting elevated LBC with an OR of 1.5 (95% CI 1.1–2.0, p = 0.004). ConclusionLBC elevation was independently associated with the presence of intra-amniotic infection and/or inflammation in women with early threatened preterm birth (gestational age < 34 weeks). This finding may support the view that an intra-amniotic inflammatory response promotes foetal lung maturation that can be detected by elevated LBC in AF.

Ultrasonographic evaluation of fetal lung histogram versus lamellar body count in the prediction of fetal lung maturity

Objective: The current study aims to compare the ultrasonographic evaluation of fetal lung Gray-level histogram width (GLHW) ratio with an amniotic fluid lamellar body count (LBC) in the prediction of fetal lung maturity. Methods: A prospective cohort study was conducted at a tertiary University Hospital in the period between May 1, 2017 and March 31, 2018. The study included pregnant women with a single fetus at ≥37 weeks of gestation scheduled for delivery by elective cesarean section (CS). Ultrasound evaluation was performed for assessment of the fetal lung to liver GLHW ratio to predict lung maturity. Lamellar body count was determined from an amniotic fluid sample obtained via amniotomy during CS. The lamellar body count for this sample was measured using a hematology analyzer. These data were further compared to Apgar scores at 1 and 5 minutes after delivery to assess the condition of the newborn immediately after birth, the degree of respiratory distress syndrome (RDS) and the need for resuscitation. Results: One hundred twenty women and their neonates were included in the study. There was a statistically significant decrease in the levels of both GLHW and LBC among those neonates that showed distressed respiration after Apgar testing as compared with those who did not show similar distress, with p-value <0.001. The Receiver Operating Characteristic Curve (ROC) for LBC levels in the prediction of respiratory distress shows the best cutoff point for LBC was found at ≤20214/μL with a sensitivity of 100.0%, specificity of 75.47% and area under the curve (AUC) of 88.4%. The ROC curve for GLWH levels in the prediction of respiratory distress shows the best cutoff point for GLWH was found at ≤0.93 with sensitivity of 100.0%, specificity of 84.91% and AUC of 97.1%. Conclusions: Ultrasonographic evaluation of GLHW of the fetal lung and liver is a non-invasive, inexpensive and time-efficient test for prediction of fetal lung maturity that has higher sensitivity and specificity.

Maternal plasma LPCAT 1 mRNA correlates with lamellar body count.

Human lysophosphatidylcholine acyltransferase 1 (hLPCAT1) is a protein which helps produce surfactant in the fetal lung. We previously reported that levels of cell-free fetal mRNA for hLPCAT1 in amniotic fluid are correlated with lamellar body count (LBC) (r2=0.93). This short communication demonstrates that fetal hLPCAT1 mRNA is also present in maternal blood. Its quantity also correlates with amniotic fluid LBC (r2=0.81). Research in maternal plasma hLPCAT1 may assist in understanding fetal and placental maturational processes.

Amniotic fluid LPCAT1 mRNA correlates with the lamellar body count.

Lysophosphatidylcholine acyltransferase 1 (LPCAT1) is required in the biosynthesis of pulmonary surfactant. This short communication describes our assessment of LPCAT1 mRNA levels in human amniotic fluid. We found a direct correlation between LPCAT1 mRNA copies and the amniotic fluid lamellar body count (LBC). This finding corroborates an association between LPCAT1 and surfactant phospholipid biosynthesis in humans. It may provide a model for future research in perinatal medicine.

Amniotic fluid lamellar body count as a novel biochemical marker for timing elective caesarean delivery

The aim of this study is to evaluate the performance of amniotic fluid lamellar body count (LBC) on the timing of elective caesarean delivery (CS) at ≥ 39 weeks. After allocating the study group (group I, transient tachypnoea of newborn (TTN), n = 14), an age-matched control group (group II, no TTN, n = 79) was selected for amniotic fluid LBC analysis. The median amniotic fluid LBC levels in group I were significantly lower than in the control group. Furthermore, the median values of mean lamellar body volume, median lamellar body distribution width and lamellar bodycrit in group I were also significantly lower than in group II. The best amniotic fluid LBC value to predict TTN was 40.15 × 103/μl, with 82.3% sensitivity and 64.3% specificity. The favourable sensitivity and specificity values to predict the TTN for amniotic fluid LBC may suggest using it as an elective caesarean delivery-time scheduling marker.

The influence of pre-eclampsia on fetal lung maturity

ObjectiveTo use amniotic fluid (AF) lamellar body count (LBC) to assess the influence of pre-eclampsia and associated pathologic conditions on fetal lung maturity (FLM). MethodsA prospective study was conducted to analyze 378 AF samples containing 5mL of AF from 306 singleton pregnancies at 26–39weeks. Stratified by gestational age groups, pregnancies were categorized as follows: pre-eclampsia (n=25); intrauterine growth restriction (IUGR) (n=74); pre-eclampsia and IUGR (n=63); and control (n=144). Amniotic fluid LBC in each group was estimated and medians were compared for defined gestational age periods. Statistical analyses were performed via non-parametric tests. ResultsBetween 31 and 33weeks, significantly lower median LBCs were found in the pre-eclampsia group than in the IUGR group (P=0.022) and in pregnancies with both entities (P=0.031). Between 34 and 36weeks, there were significantly lower median LBCs in the pre-eclampsia and the pre-eclampsia/IUGR groups than in the IUGR group (P=0.026 and P=0.004, respectively), as well as in the pre-eclampsia/IUGR group compared with the control group (P=0.04). ConclusionSignificantly lower LBCs in pre-eclamptic pregnancies between 31 and 36weeks of gestation indicate delayed FLM associated with pre-eclampsia.

Amniotic lamellar body counts can predict the occurrence of respiratory distress syndrome as well as transient tachypnea of the newborn (TTN)

The purpose of this study is to predict the occurrence of transient tachypnea of the newborn (TTN) using amniotic lamellar body count (LBC) and compare the LBCs in neonates with TTN with the LBCs in neonates with respiratory distress syndrome (RDS) and controls. Three hundred and eighty-one amniotic fluid samples were obtained at cesarean section from 27 to 40 weeks of gestation. Samples were analyzed immediately without centrifugation and the number of lamellar bodies was counted. The LBC in amniotic fluid ranged from 1,000 to 577,000/μL. An LBC cut-off value of 48,500/μL resulted in 84.7% sensitivity, 76.2% specificity, and 98.1% negative predictive value for predicting TTN. The LBC in neonates with TTN was significantly lower than that in controls (50,000 vs. 122,000; P<0.001) and significantly higher than that in neonates with RDS (50,000 vs. 21,000; P=0.042). We established a cut-off value of LBC for predicting the occurrence of TTN. The LBC in neonates with TTN was significantly lower than that in controls. Amniotic LBC can be a useful marker to predict if neonatal respiratory management is required.

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

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. 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. 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 42 x 10(3)/microl had the sensitivity of 82.4% and specificity of 64.6% in predicting the fetal lung maturity. 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.

How does amniotic fluid lamellar body count compare with FLM, PG, and L/S?

How does amniotic fluid lamellar body count compare with FLM, PG, and L/S?

Amniotic Fluid Lamellar Body Count

In Brief Objective To create a highly specific cascade testing scheme for fetal lung maturity using the lamellar body count, lecithin/sphingomyelin ratio (L/S), and phosphatidylglycerol. Methods A nondedicated hematology analyzer (Sysmex NE 1500, Toa Medical Electronics, Los Angeles, CA) was used to determine the lamellar body counts of 209 unspun amniotic fluid specimens. Maximally specific lamellar body count cutoffs for biochemical maturity and immaturity were determined using receiver operating characteristic curves. Biochemical lung maturity was defined as either a mature L/S ratio or phosphatidylglycerol. Biochemical lung immaturity was defined as both an immature L/S ratio and an immature phosphatidylglycerol. Results A lamellar body count of less than 8000 (n = 17) was 100% specific for biochemical lung immaturity (positive predictive value = 100%, negative predictive value = 86%). A lamellar body count of greater than 32,000 was 98% specific for biochemical lung maturity (positive predictive value = 99%, negative predictive value = 63%). Conclusion Testing only specimens where the lamellar body count was greater than 8000 and less than or equal to 32,000 for the L/S ratio and phosphatidylglycerol would preclude the need for 76% of all L/S and phosphatidylglycerol assays. Because the lamellar body count is quick, simple, and universally available, it could serve as an extremely cost-effective screening test for fetal lung maturity. The use of lamellar body counts in a cascade testing scheme can eliminate the need for the majority of lecithin/sphingomyelin ratios and phosphatidylglycerol assays.

Amniotic fluid lamellar body count: cost-effective screening for fetal lung maturity

Objective: To create a highly specific cascade testing scheme for fetal lung maturity using the lamellar body count, lecithin/sphingomyelin ratio (L/S), and phosphatidylglycerol. Methods: A nondedicated hematology analyzer (Sysmex NE 1500, Toa Medical Electronics, Los Angeles, CA) was used to determine the lamellar body counts of 209 unspun amniotic fluid specimens. Maximally specific lamellar body count cutoffs for biochemical maturity and immaturity were determined using receiver operating characteristic curves. Biochemical lung maturity was defined as either a mature L/S ratio or phosphatidylglycerol. Biochemical lung immaturity was defined as both an immature L/S ratio and an immature phosphatidylglycerol. Results: A lamellar body count of less than 8000 ( n = 17) was 100% specific for biochemical lung immaturity (positive predictive value = 100%, negative predictive value = 86%). A lamellar body count of greater than 32,000 was 98% specific for biochemical lung maturity (positive predictive value = 99%, negative predictive value = 63%). Conclusion: Testing only specimens where the lamellar body count was greater than 8000 and less than or equal to 32,000 for the L/S ratio and phosphatidylglycerol would preclude the need for 76% of all L/S and phosphatidylglycerol assays. Because the lamellar body count is quick, simple, and universally available, it could serve as an extremely cost-effective screening test for fetal lung maturity.

Amniotic fluid lamellar body count as a cost-effective screening test for fetal lung maturity

Amniotic fluid lamellar body count as a cost-effective screening test for fetal lung maturity

Amniotic fluid lamellar body count: a rapid and reliable fetal lung maturity test

To evaluate the lamellar body count as a predictor of fetal lung maturity. We conducted a prospective clinical outcome study. Amniocentesis was performed for evaluation of fetal lung maturity status within 72 hours of delivery in 130 patients. A lamellar body count was performed on each specimen, and a lecithin-sphingomyelin ratio and lung phospholipid profile were performed when possible (insufficient sample or contamination in eight cases). Each infant was evaluated for evidence of respiratory distress syndrome (RDS). A lamellar body count exceeding 30,000/microL predicted pulmonary maturity correctly in all cases (negative predictive value 1.00). All 16 cases of RDS had counts of 30,000/microL or less. If the lamellar body count was less than 10,000/microL, the positive predictive value for RDS was 67%, and the likelihood of a mature result from chromatographic phospholipid analysis was low (one of 14, 7%). Values between 10,000-30,000/microL indicated intermediate risk (four of 39, 10%) for developing RDS. Phospholipid analysis indicated fetal lung maturity in 35 of 39 (90%) cases with lamellar body counts in the intermediate risk range. The lamellar body count compares favorably with traditional phospholipid testing in the prediction of fetal lung maturity. Phospholipid analysis is not needed with lamellar body counts greater than 30,000/microL or less than 10,000/microL, but may be of benefit for values in the intermediate risk range. Advantages of this test include speed, objectivity, small sample volume required, and universal availability of instrumentation.