الفهرس 
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Abstract
Prior to this time, the baby is at risk for developing respiratory distress syndrome (RDS). RDS occur in about 1% of all pregnancies and it can have serious short and long-term consequences, involving both the lungs and other organs that can extend beyond period in its most severe forms.
The fetal lungs are the last organ system to “mature” so that survival outside the womb is possible. Maturity involves several components.
First, there must be sufficient surface area within the lung to allow sufficient exchange of gases (oxygen in and carbon dioxide out) to support metabolic functions. This is accomplished by millions of small sacs called alveoli that give the lungs a sponge-like appearance.
Second, the alveoli must develop to the point that the inner lining of cells (epithelial cells) that come in contact with inspired air are very thin – gas exchange can only occur over a short distance between the blood vessels in the alveoli and the air that fills the alveoli.
Third, the alveoli must be able to remain open so that the air can get into them and gas exchange can take place. The first two events are generally quite complete by about 32-34 weeks, however, the third is the most essential component from that point on and it is the focus of our fetal lung maturity testing as we shall explain.
Lamellar bodies are also defined as lysosome-related, large secretory organelles that are 0.1 to 2.4 micrometers in size. Similar to lysosomes, lamellar bodies contain soluble lysosomal enzymes, such as acid phosphatase (phospholipids) and lysosome associated membrane protrins.
Physiologically, pulmonary surfactant serves three main functions. First and foremost, it increases the compliance of the lung by decreasing the surface tension.
Second, surfactant decreases the amount of fluid accumulation in the alveoli by preserving the tendency for fluid movement into the interstitium.
Finally, the presence of surfactant maintains the equality of alveolar sz during the respiratory cycle, preserving uniform surface area and maximizing gas diffusion and ventilation throughout the pulmonary apparatus.
It was known that glucocorticoids, administrated for at least 24 h, decrease the incidence of hyaline membrane disease, a beneficial effect at least partly explained by accelerated synthesis or release of surfactant.
When babies are very premature, respiratory distress syndrome (RDS) is the result of a combination of both alveolar epithelial cell immaturity (the lining cells have not yet thinned out) and a deficiency of surfactants.
Respiratory distress syndrome (RDS), also known as hyaline membrane disease (HMD), refers to respiratory compromise presenting at or shortly after delivery due specifically to a deficiency of pulmonary surfactant.
Series of tests have been developed in an attempt to predict gestational age-related risk of developing RDS.
These can be divided into indirect, direct biochemical, and direct biophysical tests:
Indirect tests involve determination of the gestational age or size of the fetus in order to infer maturity and pulmonary status; these include calculation of the last menstrual period, appearance of heart tones, identification of the gestational sac on ultrasound, measurement of crown-rump length and biparietal diameter.
Direct biochemical tests measure the concentration of various componants of pulmonary surfactant secreted by the fetal lungs into the amniotic fluid, and include measurement of the lecithin/sphingomyelin (L/S) ratio and the phosphatidylglycerol (PG) band. Direct biophysical tests evaluate the surface-active properties of the phospholipids in pulmonary surfactant and include the foam stability index (FSI), fluorescence polarization (TDx-FLM), and the lamellar body count (LBC).
Lamellar bodies count convey many advantage: faster, more objective, less labour intensive, less technique dependent, less expensive than both PG and L/S analysis
The aim of our work is to correlate lamellar body count in amniotic fluid with fetal outcome regarding development of respiratory distress syndrome (RDS).
47 cases were studied in this study, 28 were normal full term pregnancy and 19 were preterm.
The amniotic fluid samples will be collected in the conventional blood picture tubes and were sent to the laboratory to measure the lamellar body count by the Coulter blood analyzer with no spinning of the specimen.
Regarding development of respiratory distress syndrome RDS:
Two cases in subgroup l (normal full term pregnancy) showed development of RDS resembling 7.1% of the group.
While 18 cases in the preterm subgroup developed RDS resembling 94.7% of the group.
Mean lamellar body count in newborns with RDS: 39,200 ± 12,438
With median 37,500 and interquartile range (30,500 – 47,000)
The p value for LBC was <0.0001, i.e. it is highly significant.
Mean gestational age in newborns with RDS: 33.4±1.8
The p value for gestational age was <0.0001, i.e. it is highly significant.
On studying cases which didn’t develop RDS we found that:
No. of cases was 27 cases
25 of normal full term pregnancy subgroup (92.9% of the group)
1 of the preterm subgroup (5.3% of the group)
Mean lamellar body count in newborns without RDS: 154,000 ± 84,000
With median 142,000 and interquartile range (78,000 – 199,250)
The p value for LBC was <0.0001, i.e. it is highly significant.
Mean gestational age in newborns without RDS: 38±1.3
The p value for gestational age was <0.0001, i.e. it is highly significant.
This shows that the cases developed respiratory distress syndrome (RDS) had a lower level of lamellar body count (LBC) compared to cases that didn’t develop RDS.
On correlation between LBC and RDS we found that:
There was a highly significant positive correlation (p value <0.0001)
This shows that the cases developed respiratory distress syndrome (RDS) had a Lower level of lamellar body count (LBC) compared to cases that didn’t develop RDS.
Also on correlation between LBC and gestational age:
Highly significant correlation found (p value <0.0001)
Correlation co-efficient was 0.894 using Spearman rho (ρ) correlation test.
On correlation between LBC, age and parity of the mother:
There was no statistical significance correlation between LBC and age of the mother (p value = 0.415)
There was no statistical significance correlation between LBC and parity of the mother (p value = 0.881)
ROC (receiver operator characteristics) curve showed that by using 51000/ml as a cut-off point for LBC it is a good predictor for fetal lung maturity with sensitivity 95% and specificity 96.3%.