Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The pathogenesis of NC in VLBW infants appears to be multifactorial. The vulnerability of extreme immaturity and the underdevelopment of renal function may be the most important variables. In some ways, we view this problem as similar to that of retinopathy of prematurity. (Clearly the exposure of the retina to high partial pressures of oxygen contributes to the development of retinopathy of prematurity but other variables--some known, such as an immature retina, and others not yet defined--must be present.) Hypercalciuria is common in the VLBW infant, yet not all develop NC. Decreased glomerular filtration rate, low citrate excretion, and frequently an alkaline urine are in part due to the immaturity of renal function of these infants. The need for prolonged hyperalimentation resulting in increased oxalate excretion and the development of BPD frequently requiring diuretics that may cause phosphaturia and magnesium depletion and that may increase calcium excretion are more common in the smallest and sickest of premature infants. Even transient insults to the kidneys, such as hypoxia or hypotension or the use of nephrotoxic drugs that provoke tubular injury and cell death with the probability of crystal formation and growth by way of heterogeneous nucleation, are likely to occur more frequently in this vulnerable population.
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PMID:Nephrocalcinosis. 157 67

The major fetal risk associated with elective delivery is unexpected fetal lung immaturity and the development of hyaline membrane disease soon after birth. Prior to elective vaginal or abdominal delivery it has become standard obstetric practice to predict fetal lung maturity by the analysis of amniotic fluid obtained by amniocentesis or vaginal pool sample following preterm rupture of membranes. A correlation between third-trimester fetal biparietal diameter and the lecithin/sphingomyelin (L/S) ratio has been established by several investigators. In order to determine if a threshold BPD could be consistently correlated with fetal lung maturity, we retrospectively examined the hospital and laboratory records of a group of 115 nondiabetic parturients in whom BPD measurements and amniotic fluid analysis for L/S ratio had been performed for various clinical indications. A threshold BPD of greater than or equal to 9.2 cm in all parturients who underwent elective repeat cesarean delivery was associated with no hyaline membrane disease (HMD). Two of the three neonates who developed HMD had mature L/S ratios but were products of pregnancies complicated by third-trimester hemorrhage. A review of our present data suggests that about one-third of clinically-indicated amniocenteses in the absence of maternal diabetes or third-trimester hemorrhage could potentially be avoided without adverse neonatal impact. Possible therapeutic application of this finding requires further prospective study.
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PMID:Third-trimester biparietal diameter as a predictor of fetal lung maturity. 330 Jun 78