False positive rate in newborn screening for congenital adrenal hyperplasia (CAH)-ether extraction reveals two distinct reasons for elevated 17α-hydroxyprogesterone (17-OHP) values

Background

While the sensitivity of newborn screening for the salt wasting form of congenital adrenal hyperplasia (CAH) is good, the positive predictive value is poor due to the high false positive rate of the immunological assays for 17-OHP. Cross-reactivity with steroid sulfates is one of the main causes for false positive results. Several approaches have been described to improve CAH screening: adjusting cut-off levels to gestational age or birth weight, and second-tier molecular genetic analysis or second-tier liquid chromatography-tandem mass spectrometry (TMS).

Methods

17-OHP was extracted with diethyl ether from dried blood spots in order to separate 17-OHP from polar steroids (like steroid sulfates). The dried ether extracts of calibrators, controls, and patient samples were redissolved and measured with the 17-OHP test kit (Wallac).

Results

760 normal, 1049 false positive, and 232 samples of confirmed cases with CAH were analysed. Mean 17-OHP values were significantly lower after extraction: Normal samples: 17.5 nmol/L vs. 3.2 nmol/L; false positive samples: 97.0 nmol/L vs. 25.9 nmol/L; CAH: 275 nmol/L vs. 205 nmol/L. With a cut-off value of 11.9 nmol/L (mean + 3 SD of the normal values), 404 of the false positives turned out to be normal. Ether extraction revealed two distinct subgroups of initially false positives rather than a continuum with normal distribution of 17-OHP values.

Conclusion

Diethyl ether extraction provided evidence for two causes of false positive results in CAH screening. It reduced the rate of false positives by about 40% without loss of sensitivity.     

Neonatal screening for congenital adrenal hyperplasia using 17-hydroxyprogesterone assay in filter paper blood spots

Screening of infants for congenital adrenal hyperplasia (CAH) using filter paper blood samples collected on the 5th day of life was performed with a radioimmunoassay for 17-hydroxyprogesterone without extraction with organic solvents. A total of 153,000 newborns were screened and 12 cases of CAH were detected (1:12,800). With recall levels related to gestational age, the recall rate could be lowered to 0.05%.     

21-Hydroxylase deficiency: screening and incidence in Israel

BACKGROUND: Neonatal screening for congenital adrenal hyperplasia was introduced in 1977. However, even today only a few national screening programs exist and their cost effectiveness is still debatable. This study was conducted in order to evaluate the advisability of a national or regional screening program in Israel. METHODS: From June 1987 until December 1992 we screened a countrywide random sample of 113,846 newborns for 21-hydroxylase (21-OH) deficiency measuring 17alpha-OH progesterone (17-OHP) from blood spotted on filter paper. Between January 1993 and August 1995 we continued the screening program concentrating on the population of northern Israel. A total of 56,958 newborns were screened. We compared these findings with the incidence of 21-OH deficiency in the total population born in Israel during the years 1986-1991. RESULTS: In the countrywide screening program, 4 newborns (2 Arabs and 2 Jews) were found to have levels of 17-OHP between 409 and 2,049 nmol/l (2 males and 2 females). This constitutes a low incidence of 1 in 28,462 live births. In the north-Israel screening program 4 newborns (all Arabs) were detected (2 males and 2 females) constituting a much higher incidence of 1 in 14,240 live births. The data obtained from the archives revealed that the incidence of 21-OH deficiency nationwide during the years 1986-1991 was 1:19,000 live births, 1:30,000 for Jews and 1:8,000 for Arabs. The incidence of 21-OH deficiency among Arab newborns in the northern part of the country was as high as 1:5,000 (14:71,130). The female to male (F:M) ratio was 2.6:1 and the ratio of the salt-losing to the simple virilizing variant was 5:1. Two male patients were diagnosed prenatally, 21 patients (17 F and 4 M) during the first month after birth and 6 others subsequently. CONCLUSIONS: The high F:M ratio of 21-OH deficiency in the total population compared to a 1:1 ratio in our random screening programs suggests that 21-OH-deficient male patients in the general population might have been missed or died early due to a salt-losing crisis. The high incidence of this disease in the northern part of the country and especially among the Arabs, suggests that screening in this part of the country, especially among the Arab population, is warranted and might save the lives of some male patients.     

Precursor-to-product ratios reflect biochemical phenotype in congenital adrenal hyperplasia

Precursor-to-product ratios in steroid hormone metabolism may accurately reflect enzymatic activity and production of metabolites relative to their disappearance. The purpose of this study was to explore the use of direct precursor-to-product steroid ratios to discriminate between infants with congenital adrenal hyperplasia (CAH) due to 21-α-hydroxylase deficiency and infants with no disorder, thus characterizing the biochemical phenotype in CAH. Deidentified dried blood spot samples from confirmed CAH cases identified by newborn screen (CAH-positive, N = 8) and from cases with no disorder (CAH-negative, N = 10) were obtained from the California State Newborn Screening Program. Samples (~6.25 mm circular spots) underwent methanol and water extraction (9:1 ratio). Deuterated steroids served as isotope internal standards. 17-α-hydroxyprogesterone (17-OHP), 11-deoxycortisol (S), androstenedione (A4) and cortisol (F) concentrations were determined by liquid chromatography–tandem mass spectrometry (LC–MS/MS), and the 17-OHP/S, 17-OHP/A4, and S/F ratios were calculated. The mean 17-OHP and A4 concentrations in samples from CAH cases were significantly increased when compared to cases with no disorder (p = 0.003 for both). 17-OHP/S and 17-OHP/A4 ratios were also significantly elevated in CAH cases (p = 0.007 and p < 0.001, respectively). In contrast, S and F concentrations and the S/F ratio were similar between the two groups. In CAH, the elevated 17-OHP/S ratio is a biomarker of diminished 21-α-hydroxylase activity, and the elevated 17-OHP/A4 ratio is a biomarker of adrenal androgen excess via increased 17,20-lyase activity. The similar S/F ratio indicates that the rate of production via 11-β-hydroxylase and disappearance of F is maintained in CAH.     

Extraovarian steroid cell tumor 'not otherwise specified' as a rare cause of virilization in twelve-year-old girl.

BACKGROUND: We present a 12-year-old girl with a 5-year history of progressive virilization. RESULTS: Regarding elevated plasma levels of 17-hydroxyprogesterone (17-OHP) and androgens, normal ultrasound and CT scan of ovaries and adrenal glands, the nonclassic form of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency was presumed the cause of virilization. As the glucocorticoid therapy did not normalize high levels of 17-OHP and androgens, and the DNA analysis did not demonstrate a mutation causing CAH, a laparotomy was performed. Near the right ovary a tumor was found and extirpated. Pathohistological studies determined it to be a rare steroid cell tumor, 'not otherwise specified'. Within the next months the signs of virilization resolved and menarche occurred. CONCLUSIONS: Steroid cell tumor should be considered in differential diagnosis of virilization in childhood. Regarding the age of our patient and pathohistological findings of the tumor, her prognosis is favorable.     

不同胎龄早产儿早期凝血指标的变化及其临床意义

目的:研究不同胎龄早产儿早期凝血指标的变化及其临床意义。方法:选取2012年1月至2017年7月期间我院出生的新生儿392例为研究对象。根据新生儿胎龄的不同分为早期早产儿组(胎龄27~31周)78例、中期早产儿组(胎龄32~33周)102例、晚期早产儿组(胎龄34~36周)116例以及足月新生儿组(胎龄37~42周)96例。四组新生儿出生后2h内抽取静脉血检测凝血指标,包括凝血酶原时间(PT)、活化部分凝血酶原时间(APTT)、纤维蛋白原(FIB),并应用Pearson相关性分析分析新生儿胎龄与上述各项凝血指标水平的相关性。结果:早期早产儿组、中期早产儿组、晚期早产儿组、足月新生儿组的出生体重以及胎龄呈逐渐上升趋势,不同组别新生儿的出生体重以及胎龄差异均有统计学意义(P0.05)。早期早产儿组、中期早产儿组、晚期早产儿组、足月新生儿组PT、APTT均呈逐渐下降趋势,FIB呈逐渐上升趋势,不同组别新生儿PT、APTT、FIB差异均有统计学意义(P0.05)。Pearson相关性分析显示,新生儿胎龄与PT、APTT呈负相关(r=-0.567、-0.691,P=0.000、0.000),而新生儿胎龄与FIB水平呈正相关(r=0.623,P=0.000)。结论:不同胎龄早产儿早期凝血功能存在异常变化,新生儿胎龄与PT、APTT均呈负相关关系,与FIB呈正相关关系,临床应予以重视,及时检测其凝血指标,必要时应予以干预治疗。     

Some essential elements in maternal and cord blood in relation to birth weight and gestational age of the baby

Maternal and cord blood were collected from 54 Indian women at parturition and analyzed for Zn, Cu, and Fe by flame atomic absorption spectrophotometry to determine the relationship between levels of these elements in mother’s and infant’s blood and maternal age, birth weight, and gestational age of the baby. The blood Zn level of mothers in the age group 24–28 yr was significantly higher than those of mothers in the age group of 18–23 yr (p<0.05). Similarly, mothers in the 24 to 28-yr group also had higher blood Fe level than mothers in the group 29–38 yr (p<0.05). The levels of Zn, Cu, and Fe were higher in the maternal blood and lower, but not significantly, in the cord blood of low-birth-weight babies than in those of normal-birth-weight babies. However, differences in the levels of Zn, Cu, and Fe between maternal and cord blood of the two birth-weight groups was statistically significant. There were no significant differences in the levels of the three elements in maternal or cord blood by the gestational age of the baby. A weak but significant correlation was found between the birth weight of the baby and the Fe level in the cord blood (r=0.26; p<0.05). Also, weak significant correlations were observed between gestational age of the baby and Fe (r=0.23; p<0.05) and Cu (r=0.31; p<0.05) levels in the cord blood. Although, there are many confounders of low birth weight and preterm deliveries, a diminished placental transfer of these essential elements could be one of the several etiological factors for low birth weight of newborns.     

Relation of cord blood thyroxine and thyrotropin levels to gestational age and birth weight.

A program of screening cord blood for evidence of primary neonatal hypothyroidism was implemented in a general hospital. In 13 months 3456 newborns were screened: the thyroxine (T4) and triiodothyronine (T3) concentrations were measured in cord blood samples, and when the T4 level was below 8.0 micrograms/dl thyrotropin was also assayed in the sample. The two-tier program was effective. One hypothyroid newborn was detected and treated. More boys than girls had T4 levels below 8.0 micrograms/dl (9.7% v. 4.7%). The T4 level correlated with birth weight slightly better in the boys (r = 0.28 v. 0.21), and in the boys this correlation was stronger when the birth weight was lower. Regression analysis of the data for 54 sets of twins indicated that the T4 level was more strongly related to gestational age than to birth weight.     

Quality of antenatal care and its dose-response relationship with birth weight in a maternal and child health training institute in Bangladesh

Four hundred and sixty-five pregnant women and their newborn babies were studied at a maternal and child health training institute in Dhaka, Bangladesh, between July 2002 and June 2003 with the objective of (1) examining the relationship between birth weight and maternal factors, and, if there was a dose-response relationship between quality of antenatal care and birth weight, (2) predicting the number of antenatal visits required for women with different significant characteristics to reduce the incidence of low-birth-weight babies. The study revealed that 23.2% of the babies were of low birth weight according to the WHO cut-off point of <2500 g. Mean birth weight was 2674.19+/-425.31 g. A low birth weight was more common in younger (<20 years) and older (> or =30 years) mothers, the low-income group and those with little or no education. The mean birth weight of the babies increased with an increase in quality of antenatal care. The babies of the mothers who had 6+ antenatal visits were found to be 727.26 g heavier than those who had 1-3 visits and 325.88 g heavier than those who had 4-5 visits. No significant relationship was found between number of conception, birth-to-conception interval, BMI at first visit, sex of the newborn and birth weight. Further, from multiple regression analysis (stepwise), it was revealed that number of antenatal visits, educational level of the mother and per capita yearly income had independent effects on birth weight after controlling the effect of each variable. Using multiple regression analysis, the estimated number of antenatal visits required to reduce the incidence of low-birth-weight babies for women with no education and below-average per capita income status was 6; the number required for women with no education and above-average per capita income status was 5; and that for women with education and with any category of income status was 4 visits. So there is a need to stratify women according to their income and educational status so that, along with other measures, the required number of antenatal visits can be estimated beforehand to reduce the incidence of low-birth-weight babies.     

Refractive Status at Birth: Its Relation to Newborn Physical Parameters at Birth and Gestational Age

Background

Refractive status at birth is related to gestational age. Preterm babies have myopia which decreases as gestational age increases and term babies are known to be hypermetropic. This study looked at the correlation of refractive status with birth weight in term and preterm babies, and with physical indicators of intra-uterine growth such as the head circumference and length of the baby at birth.

Methods

All babies delivered at St. Stephens Hospital and admitted in the nursery were eligible for the study. Refraction was performed within the first week of life. 0.8% tropicamide with 0.5% phenylephrine was used to achieve cycloplegia and paralysis of accommodation. 599 newborn babies participated in the study. Data pertaining to the right eye is utilized for all the analyses except that for anisometropia where the two eyes were compared. Growth parameters were measured soon after birth. Simple linear regression analysis was performed to see the association of refractive status, (mean spherical equivalent (MSE), astigmatism and anisometropia) with each of the study variables, namely gestation, length, weight and head circumference. Subsequently, multiple linear regression was carried out to identify the independent predictors for each of the outcome parameters.

Results

Simple linear regression showed a significant relation between all 4 study variables and refractive error but in multiple regression only gestational age and weight were related to refractive error. The partial correlation of weight with MSE adjusted for gestation was 0.28 and that of gestation with MSE adjusted for weight was 0.10. Birth weight had a higher correlation to MSE than gestational age.

Conclusion

This is the first study to look at refractive error against all these growth parameters, in preterm and term babies at birth. It would appear from this study that birth weight rather than gestation should be used as criteria for screening for refractive error, especially in developing countries where the incidence of intrauterine malnutrition is higher.     

Automated, fast and sensitive quantification of 17 alpha-hydroxy-progesterone, androstenedione and testosterone by tandem mass spectrometry with on-line extraction

Plasma 17 alpha-hydroxyprogesterone (17-OHP), androstenedione and testosterone measurements are important for the diagnosis and monitoring of hyperandrogenic disorders, most importantly for congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency. The reliability of immunoassays has proved questionable especially for newborns and children. In order to reduce the analytical interferences due to cross-reactivity or matrix effects, to improve accuracy and shorten the analysis time, we have developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method with atmospheric pressure chemical ionization (APCI) for simultaneous measurement. An on-line extraction cartridge with column-switching technique and liquid chromatography over a Chromolith RP 18 e column allow a rapid and easy quantification. The lowest limit of detection was 0.03-0.06 microg/L. Our method has proved linear up to 250 microg/L (r=0.999). Recoveries (S.D.) of 17-OHP, androstenedione and testosterone in plasma were 100% (5), 102% (2) and 92% (4), respectively. The regression equation for the LC-MS/MS (x) and immunoassay (y) methods for 17-OHP (excluding neonate samples) was y=1.942 x+0.255 nmol/L (r=0.695; n=97). In comparison to our values, the immunoassay generally overestimates steroid concentration. The regression equation for the LC-MS/MS (x) and immunoassay (y) methods for testosterone was y=0.963 x+0.035 nmol/L (r=0.955; n=107). Preliminary reference intervals for children were determined as a function of age and sex. The sensitivity and specificity of the LC-MS/MS method offer advantages over routine immunoassays due to the elimination of interferences especially for newborns, high throughput and short chromatographic run time.     

Plasma F2-isoprostanes are elevated in newborns and inversely correlated to gestational age

F(2)-isoprostanes, prostaglandin F(2)-like compounds formed by free radical-catalyzed lipid peroxidation, are considered the most reliable markers of oxidative stress. It has been repeatedly suggested that newborns are exposed to conditions of oxidative stress resulting from the change from a low oxygen pressure in utero to a high oxygen pressure at birth. We measured the levels of F(2)-isoprostanes in plasma of newborns by gas chromatography/mass spectrometry and we found that F(2)-isoprostanes are significantly higher in term newborns compared to healthy adults. The greatest values were found in preterm newborns in whom F(2)-isoprostanes are even higher than in term babies. Moreover a significant inverse correlation was found between the plasma levels of isoprostanes and the gestational age. A quite normal level of isoprostanes was found in the mothers both at delivery and during pregnancy. Placental total F(2)-isoprostanes (sum of free plus esterified) were significantly higher in preterm compared to term deliveries and such a difference might account for the difference in plasma isoprostanes. Plasma non-protein-bound iron is higher in preterm than in term newborns, even if no correlation was found with plasma F(2)-isoprostanes. Erythrocyte desferrioxamine-chelatable iron content (0 time) and release (24 h of aerobic incubation) are higher in newborns than in adults and in preterm than in term newborns, but again no correlation was found with plasma F(2)-isoprostanes. The marked increase in plasma isoprostanes suggests that oxidative stress is a feature of the physiopathological changes seen in the perinatal period.     

Prevalence of congenital hypothyroidism in Isfahan, Iran: results of a survey on 20,000 neonates

AIMS: To evaluate the prevalence of congenital hypothyroidism (CH) in a screening program performed for the first time in Isfahan, Iran. METHODS: From May 2002 to December 2002, T4 and TSH serum concentrations of 20,000 3- to 7-day-old newborns, born in all 17 hospitals of the city, were measured by radioimmunoassay and immunoradiometric assay, respectively. The newborns with abnormal screening results (TSH >20 mIU/l, T4 <6.5 microg/dl and based on the weight) were re-examined. RESULTS: Of 531 recalled subjects (recall rate 2.6%), 54 were confirmed to be hypothyroid, showing a prevalence of 1:370 for CH. CONCLUSION: Considering the high frequency of CH, the necessity of implementing a routine screening program in the healthcare system of Isfahan Province is emphasized.     

Functional abilities at age 4 years of children born before 29 weeks of gestation.

OBJECTIVES--To assess the rate of impairment and disability among babies born very preterm and to investigate the association between such impairment and gestational age at birth. DESIGN--Cohort study of a geographically defined population of babies. SETTING--Oxford Regional Health Authority. SUBJECTS--All babies born alive before 29 weeks of gestation to mothers resident in the region during 1984-6. MAIN OUTCOME MEASURES--Survival rates and rates of impairment and disability among survivors at the age of 4 years. RESULTS--Of the 342 babies, half (170) survived to be discharged home. Of the 164 survivors to age 4 years, 153 (93%) were assessed. A total of 35 (23%; 95% confidence interval 16% to 30%) were severely disabled and only 54 (35%; 28% to 43%) were unimpaired. The risk of impairment and disability increased with decreasing gestational age at birth (p < 0.003). CONCLUSIONS--With the increasing survival rate among babies born before 29 weeks of gestation, we need urgently to establish reliable ways of monitoring the proportion of survivors who have a disability.     

Estimation of gluconeogenesis in newborn infants

The rate of glucose turnover (R(a)) and gluconeogenesis (GNG) via pyruvate were quantified in seven full-term healthy babies between 24 and 48 h after birth and in twelve low-birth-weight infants on days 3 and 4 by use of [(13)C(6)]glucose and (2)H(2)O. The preterm babies were receiving parenteral alimentation of either glucose or glucose plus amino acid with or without lipids. The contribution of GNG to glucose production was measured by the appearance of (2)H on C-6 of glucose. Glucose R(a) in full-term babies was 30 +/- 1.7 (SD) micromol. kg(-1). min(-1). GNG via pyruvate contributed approximately 31% to glucose R(a). In preterm babies, the contribution of GNG to endogenous glucose R(a) was variable (range 6-60%). The highest contribution was in infants receiving low rates of exogenous glucose infusion. In an additional group of infants of normal and diabetic mothers, lactate turnover and its incorporation into glucose were measured within 4-24 h of birth by use of [(13)C(3)]lactate tracer. The rate of lactate turnover was 38 micromol. kg(-1). min(-1), and lactate C, not corrected for loss of tracer in the tricarboxylic acid cycle, contributed approximately 18% to glucose C. Lactate and glucose kinetics were similar in infants that were small for their gestational age and in normal infants or infants of diabetic mothers. These data show that gluconeogenesis is evident soon after birth in the newborn infant and that, even after a brief fast (5 h), GNG via pyruvate makes a significant contribution to glucose production in healthy full-term infants. These data may have important implications for the nutritional support of the healthy and sick newborn infant.     

Longitudinal assessment of pituitary-thyroid axis and adrenal function in preterm infants raised by 'kangaroo mother care'

OBJECTIVE: To assess whether complete kangaroo mother care (KMC), a skin-to-skin contact intervention, would affect longitudinal/developmental patterns of hormonal change. METHOD: An open randomized controlled trial was conducted in a large tertiary care hospital, comparing KMC and traditional care for newborn infants weighing less than 2,001 g. Eighty-seven healthy preterm (<37 weeks gestational age) infants from this study provided three blood-spot samples on filter paper: at randomization (postnatal age 1-5 days), 2 weeks later, and at calculated term (41 weeks gestational age). They met a number of additional inclusion criteria including discharge from the hospital within the first postnatal week. The levels of 17alpha-hydroxy-progesterone (17-OHP), thyroxine-stimulating hormone (TSH) and thyroxine (T(4)) were assessed by radioimmunoassay. Birth weight (<1,800 or > or =1,800 g) and prenatal maternal corticosteroid treatment were taken into account in the analysis. INTERVENTIONS: Complete KMC includes early discharge, positioning the infant on the parent's chest in an upright position, 24 h/day in skin-to-skin contact, and breast-feeding. In the traditional care group, infants were discharged according to routine hospital practice. RESULTS: Levels of 17-OHP and TSH decreased significantly from eligibility to calculated term while T(4) levels did not change significantly over time. Most importantly, overall, treatment (KMC) did not interact with the pattern of physiological change. CONCLUSIONS: Maturation of the pituitary-thyroid axis and adrenal function is apparently not compromised by KMC, at least in healthy preterm infants.     

Preterm or Not – An Evaluation of Estimates of Gestational Age in a Cohort of Women from Rural Papua New Guinea

BackgroundKnowledge of accurate gestational age is required for comprehensive pregnancy care and is an essential component of research evaluating causes of preterm birth. In industrialised countries gestational age is determined with the help of fetal biometry in early pregnancy. Lack of ultrasound and late presentation to antenatal clinic limits this practice in low-resource settings. Instead, clinical estimators of gestational age are used, but their accuracy remains a matter of debate.MethodsIn a cohort of 688 singleton pregnancies from rural Papua New Guinea, delivery gestational age was calculated from Ballard score, last menstrual period, symphysis-pubis fundal height at first visit and quickening as well as mid- and late pregnancy fetal biometry. Published models using sequential fundal height measurements and corrected last menstrual period to estimate gestational age were also tested. Novel linear models that combined clinical measurements for gestational age estimation were developed. Predictions were compared with the reference early pregnancy ultrasound (<25 gestational weeks) using correlation, regression and Bland-Altman analyses and ranked for their capability to predict preterm birth using the harmonic mean of recall and precision (F-measure).ResultsAverage bias between reference ultrasound and clinical methods ranged from 0–11 days (95% confidence levels: 14–42 days). Preterm birth was best predicted by mid-pregnancy ultrasound (F-measure: 0.72), and neuromuscular Ballard score provided the least reliable preterm birth prediction (F-measure: 0.17). The best clinical methods to predict gestational age and preterm birth were last menstrual period and fundal height (F-measures 0.35). A linear model combining both measures improved prediction of preterm birth (F-measure: 0.58).ConclusionsEstimation of gestational age without ultrasound is prone to significant error. In the absence of ultrasound facilities, last menstrual period and fundal height are among the more reliable clinical measures. This study underlines the importance of strengthening ultrasound facilities and developing novel ways to estimate gestational age.     

Late-onset adrenal hyperplasia in north Indian hirsute women

The occurrence of late-onset congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency was studied in 60 consecutive hirsute women by means of adrenocorticotrophin (ACTH)-stimulated serum 17-hydroxyprogesterone (17-OHP) levels. Five (8.3%) women had an exaggerated response (ACTH-stimulated 17-OHP 3,160 +/- 560 ng/dl). All of them had regular periods and 3 were virilized. The other 2 were indistinguishable from those with idiopathic hirsutism or polycystic ovarian disease.     

Changes of several adrenal delta 4-steroids measured by HPLC-UV spectrometry in neonatal patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency

We have developed an easy and rapid method of reverse-phase high-performance liquid chromatography (HPLC)-UV spectrometry for measuring adrenal delta 4-steroids. Three female neonates with adrenal 21-hydroxylase deficiency (2 salt-losers and 1 simple virilizer), two of whom were recalled by neonatal mass-screening for congenital adrenal hyperplasia (CAH), were diagnosed using this method. Changes of several adrenal steroids were examined in these patients before and after treatment with hydrocortisone. Before treatment, the cortisone and cortisol peaks were very low and those of 17 alpha-hydroxyprogesterone (17-OHP) and 21-deoxycortisol (21-DOF) were high in all 3 patients (17-OHP: 79.9-997 nmol/l, 21-DOF: 83.7-324 nmol/l). The androstenedione peak was also high in 2 of them. A peak produced by 21-deoxycortisone, which is a product of oxidation of 21-DOF at the C-11 position, was also detected in all cases (14.5-297 nmol/l). After treatment, all of these abnormally elevated delta 4-steroids decreased or disappeared. This new method is thought to be valuable for the rapid diagnosis of CAH, and especially for use in neonatal mass-screening for CAH.     

Nonspecific killer cells in premature and mature neonates and infants

K (killer) and natural killer (NK) cells were investigated in peripheral blood of 76 children, preterm small for date babies (n = 8), preterm babies (n = 15), fullterm small for date babies (n = 6) fullterm babies (n = 7) and infants up to 12 months age (n = 40). The K and NK cell activity of human leukocytes was analysed as compared with those cells of the K 562 cell line and murine cells covered by xenologous antibodies in Graffi erythroblast leukemia by means of the 51Cr release test. K cell activities were significantly lower in preterm small for date babies to infants with 1-12 months of age. In our results it is shown that NK capacity of preterm or term newborns and infants up to 6 months age does not differ significantly from each other. Children who are 6-12 months old will have significantly higher NK cell activities. It can be concluded that K cell activities are fully developed during pregnancy and NK cell activities later when the children are between 6 and 12 months of age.