Mutational spectrum of steroid 21-hydroxylase and the genotype-phenotype association in Middle European patients with congenital adrenal hyperplasia.

OBJECTIVE: To analyze the mutational spectrum of steroid 21-hydroxylase (CYP21) and the genotype- phenotype correlation in patients with congenital adrenal hyperplasia (CAH) registered in the Middle European Society for Pediatric Endocrinology CAH database, and to design a reliable and rational approach for CYP21 mutation detection in Middle European populations. DESIGN AND METHODS: Molecular analysis of the CYP21 gene was performed in 432 CAH patients and 298 family members. Low-resolution genotyping was performed to detect the eight most common point mutations. High-resolution genotyping, including Southern blotting and sequencing was performed to detect CYP21 gene deletions, conversions, point mutations or other sequence changes. RESULTS: CYP21 gene deletion and In2 and Ile172Asn mutation accounted for 72.7% of the affected alleles in the whole study group. A good genotype-phenotype correlation was observed, with the exception of Ile172Asn and Pro30Leu mutations. In 37% of patients low resolution genotyping could not identify the causative mutation or distinguish homozygosity from hemizygosity. Using high-resolution genotyping, the causative mutations could be identified in 341 out of 348 analyzed patients. A novel mutation Gln315Stop was found in one simple virilising CAH (SV-CAH) patient from Austria. In the remaining seven patients polymorphisms were identified as the leading sequence alteration. The presence of elevated basal and ACTH-stimulated 17-hydroxyprogesterone, premature pubarche, advanced bone age and clitoral hypertrophy directly implicated Asn493Ser polymorphism in the manifestation of nonclassical- (NC) and even SV-CAH. CONCLUSIONS: By genotyping for the most common point mutations, CYP21 gene deletion/conversion and the 8 bp deletion in exon 3, it should be possible to identify the mutation in 94-99% of the diseased alleles in any investigated Middle European population. In patients with a mild form of the disease and no detectable mutation CYP21 gene polymorphisms should be considered as a plausible disease-causing mutation.

Lessons from 30 years of clinical diagnosis and treatment of congenital adrenal hyperplasia in five middle European countries.

Despite the fact that congenital adrenal hyperplasia (CAH) is one of the most common inborn endocrine disorders, some patients are not identified, or may even die, in an acute salt-losing crisis. In a retrospective study covering the last 30 yr, we examined the time elapsing before diagnosis of CAH patients, in 5 Middle European countries, and the mortality rate in diagnosed patients and their siblings during childhood; we also attempted to estimate how many patients are not diagnosed clinically each year. Basic and follow-up clinical data and the family histories of 484 patients with classical forms of CAH diagnosed between 1969 and 1998 were collected and recorded in 5 Middle European countries. The sex-ratio, time elapsing before diagnosis, and mortality among siblings and patients were calculated, and the number of undiagnosed patients was estimated. We found significantly fewer genetic males (43.0%) than females (57.0%) among 484 classic CAH patients, and the percentage of diagnosed boys did not increase with time; 64.7% of them suffered from the salt-wasting (SW) form, and 35.3% from the simple virilizing (SV) form, of the disease. The diagnosis of CAH was established significantly later in males than in females in both forms [SW: 26 vs. 13 days (median), P < 0.0001; SV: 5.0 vs. 2.8 yr, P = 0.03]. Infant mortality in the general population was significantly lower than in either siblings (1.8% vs. 7.0%; P < 0.0001) or in SW (2.29% vs. 11.3%; P < 0.0001). According to our calculations, by our current praxis of clinical ascertainment, 2-2.5 SW and up to 5 SV stay undiagnosed, out of 40 expected CAH patients per year in the countries investigated. Both clinical detection and treatment of CAH patients, at least in males, were insufficient in the five Middle European countries examined during the last 30 yr. Neonatal mass screening and/or greater awareness of the medical community are discussed as ways of improving the efficacy of CAH management. Our experience may be applicable to other countries with similar health care systems.

Serum ECP taken in the acute episode of bronchial obstruction can predict the development of bronchial asthma in young children.

For the early institution of anti-asthma treatment, reliable markers distinguishing the children with asthma from children with virus-associated wheeze are needed. Serum eosinophilic cationic protein (ECP) has been suggested as a marker correlating with the intensity of eosinophilic inflammation. We have studied 27 children (age 3 to 35 months) admitted with acute bronchial obstruction. Each child had been followed for 12 months after the first episode and then assigned to one of two groups (asthma or non-asthma) based on the clinical course. Serum ECP (s-ECP) was taken at the acute episode and again at least 6 months later, when the child was completely symptom-free. Serum ECP was analyzed using the Pharmacia CAP ECP FEIA immunofluorescence system. Mean s-ECP during the acute episode was 26.5 micrograms/L (5.5-69) in the asthma group (n = 14) and 9.7 (5.2-17 micrograms/L) in the non-asthmatics (n = 13), p < 0.01. There was no difference in the s-ECP analyzed during the symptom-free period. Elevated values of serum ECP taken during, but not outside, the acute episodes of bronchial obstruction may be helpful in predicting the development of bronchial asthma in young children with acute obstructive episodes.

Intratracheal furosemide in infants after cardiac surgery: its effects on lung mechanics and urinary output, and its levels in plasma and tracheal aspirate.

OBJECTIVE: Recent studies have suggested direct pulmonary effects of furosemide in asthmatics and infants with bronchopulmonary dysplasia. We tested the hypothesis that intratracheally administered furosemide also increases respiratory compliance in children after cardiac surgery, and investigated whether furosemide has a topical and/or systemic action. STUDY DESIGN: Prospective study with intra-individual control. In twelve infants and toddlers (age: 10 +/- 8 months, weight: 6.9 +/- 3 kg) mechanically ventilated for compromised lung mechanics after cardiac surgery, 0.5 mg/kg furosemide was intratracheally administered to the lungs. Lung mechanics were serially assessed using a computerised system (Sensormedics 2600) during a 2 h control and 2 h intervention period. Urine output was measured by an indwelling bladder catheter and levels of furosemide were determined in blood and tracheal aspirates. RESULTS: Static compliance improved within 30 min in all patients, reached a maximum of 44 (20-85)% above baseline and remained improved throughout the study (p < 0.05). An immediate, short and significant diuretic effect of intratracheally applied furosemide was observed. Furosemide levels 1 h after intervention were 795 ng/ml in the blood and 431 micrograms/ml (i.e. 1000-fold higher) in the tracheal aspirate. Changes in compliance were correlated only to urine output values over the 2 h (r = 0.82, p = 0.044, n = 9) after furosemide administration. CONCLUSION: We conclude that intratracheally applied furosemide improves static compliance in infants and toddlers with compromised lung mechanics after cardiac surgery. We demonstrated that furosemide is absorbed from the lung and has a systemic effect within 15 min after its intratracheal instillation.

Quasistatic volume-pressure curve to predict the effects of positive end-expiratory pressure on lung mechanics and gas exchange in neonates ventilated for respiratory distress syndrome.

The shape of the volume-pressure (V/P) curve indicates alveolar collapse if it is convex to the pressure axis and indicates overdistension if it is concave. Positive end-expiratory pressure (PEEP) should either improve or decrease compliance and oxygenation in neonates ventilated for respiratory distress syndrome (RDS), depending on predominance of either alveolar collapse or overdistension. To test this hypothesis, we determined quasistatic V/P curves in 13 preterm neonates and characterized their shape by an alveolar distension index (ADI) at PEEP levels of 2, 4, and 6 cm H2O. We calculated the ADI dividing the V/P ratio at a low tidal volume by the V/P ratio at a high tidal volume. This ADI was then related to the effect of PEEP changes on respiratory compliance and alveolar to arterial oxygen tension difference (AaDO2). ADI was assumed to indicate alveolar collapse if less than 1 and overdistension if more than 1. An increased PEEP in neonates with alveolar collapse (ADI less than 1) decreased AaDO2 more (12 vs 10 mm Hg/cm PEEP, not significant) and decreased compliance less (3 vs 17%/cm PEEP; P < 0.05) than in those neonates with alveolar overdistension (ADI more than 1). Conversely, a decreased PEEP in neonates with alveolar overdistension increased compliance more (19 vs 5%; not significant) and increased AaDO2 less (7 vs 26 mm Hg; P < .01) than in those with alveolar collapse. AaDO2 and compliance changes after PEEP alterations were significantly correlated to the ADI before PEEP alterations (P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Measurement of airway resistance in awake cats.

Airway resistance (Raw) measurement with continuous recording was studied in 10 awake cats. The method used was a transducer enabling to incorporate additive resistances by rotating blind. The signals were processed electronically. Part of the measuring device in a pneumotachographic transducer (measurement V') and VT is obtained by integrating V'. Values for mean Raw were read in both parts of the breathing cycle. The experiments have shown that the method could be used in awake cats. Values for mean Rawinsp. were 1.3 +/- 0.24 kPa.l-1.s, Rawexp. of 1.43 +/- 0.26 kPa.l-1.s, end-inspiratory Raw was 1.44 +/- 0.33 kPa.l-1.s and end-expiratory Raw of 1.49 +/- 0.31 kPa.l-1.s.