Biomedical subjects
A Prader
Publications and source records attributed to A Prader.
Loss and recovery of trabecular bone in the distal radius following fracture--immobilization of the upper limb in children.
Computed tomography of the human radius is performed using a special purpose scanning device which incorporates a radionuclide (125I) as radiation source. Parameters decribing the trabecular bone and the compact bone are determined at a distal and a diaphyseal measuring site respectively. Using this measurement technique changes in bone mineralization in the radius were studied in a group of 23 children following immobilization of an upper limb for fracture healing. An immobilization period of between three to six weeks resulted in a reduction of the relevant parameter value of up to 44% (mean 16%) in the distal part of the radius, whereas no significant change could be seen in the diaphyseal part of the same bone. Rapid remineralization of trabecular bone is indicated by the increase of the corresponding parameter value at a rate of up to several percent per week. However, in some of the patients studied complete normalization was not attained during the first six months following cast removal.
Low urinary estriol during pregnancy caused by isolated fetal ACTH-deficiency.
In a 34-year-old pregnant woman, serum HPL and urinary HCG were normal, but urinary estriol was repeatedly low. A normal boy was delivered after 38 week gestation. During the neonatal period, he had hypoglycemia, muscular hypotonia and transient hyperbilirubinemia. The ACTH-test was normal, but the THS-response to metyrapone was low. Serum ACTH did not respond to insulin and metyrapone. Growth hormone, TSH and gonadotropin responses to stimuli were normal. Treatment with hydrocortisone resulted in disappearance of the symptoms. It is concluded that fetal ACTH-deficiency is one of the specific endocrine causes of low maternal estriol.
Bone densitometry using computed tomography. Part I: selective determination of trabecular bone density and other bone mineral parameters. Normal values in children and adults.
Gamma-ray computed tomography (gamma-ray CT), using a special purpose scanner, enables in-vivo quantitative analysis of bone mineralization. Trabecular bone density (TBD), the relative amount of compact bone (bone density, BD) and the total absorption (TA) for a cross-section of the radius are determined from measurements of local linear absorption coefficients. A preliminary study of normal children (n = 49) and adults (n = 34) indicated that TBD is independent of age and sex in the age range 4 to 40 years. DB remains constant throughout childhood but increases after puberty in both women and men. TA is higher for adults than for children, and also higher for men than for women. A correlation between TA and parameters relating to body size indicates a relationship between body weight and bone mass.
Bone densitometry using computed tomography. Part II: increased trabecular bone density in children with chronic renal failure.
The method of gamma-ray computed tomography (gamma-ray CT) bone densitometry described in the preceding article provides selective determination of trabecular bone density (TBD), the relative amount of compact bone (bone density, BD), and the total absorption (TA) within a bone cross section. Seven of nine children with chronic renal failure (CRF), and selected only on the basis of their serum creatinine value (greater than 5 mg/100 ml), had increased TBD values above the normal range, whereas the other bone mineral parameters were normal. Radiographic signs of secondary hyperparathyroidism (subperiosteal erosions, cysts) were reported in the five patients with the highest TBD values, whereas the subjective diagnosis of osteosclerosis reported in three of these five and in one other patient correlated less well with the TBD increases. However, this is the first report of an objective, non-invasive documentation of the radiological finding of osteosclerosis in CRF. It also explains why methods for bone mineral measurements used previously, such as a photon absorptiometry which provides only a parameter equivalent to TA, failed to reveal increases in bone mineral content in renal osteodystrophy even when signs of osteosclerosis were present. Thus, gamma-ray CT helps to document objectively the degree of osteosclerosis and its location.
Unusual heterozygotes of congenital adrenal hyperplasia due to 21-hydroxylase deficiency confirmed by HLA tissue typing.
In a previous publication, three relatives of patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency from two families were considered to be unusual heterozygotes rather than homozygotes with mild clinical manifestations. Their heterozygosity could now be confirmed by HLA tissue typing.
Possible genetic linkage disequilibrium between HLA and the 21-hydroxylase deficiency gene (congenital adrenal hyperplasia).
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Hearing impairment following therapy of Haemophilus influenzae meningitis.
From 97 children with bacteriologically confirmed Haemophilus influenzae meningitis, 39 were treated with chloramphenicol (before 1970) and 58 with ampicillin (since 1970). In 1977 all patients were followed up with history, clinical examination, and audiometry. Sensorineural hearing defect was found in 5 chloramphenicol patients and in 10 ampicillin patients. Of the 82 patients for whom treatment was begun within 48 h of onset of symptoms, only two showed hearing deficit, while 13 of the 15 patients in whom treatment was begun later suffered from hearing impairment. It appears that it is not the antibiotic, but the delay between onset of symptoms and start of therapy, that is decisive for the occurrence of inner ear impairment.
Silver-Russell syndrome. Observations in 20 patients.
The growth and development data of 20 patients with the Silver-Russell syndrome (14 boys, 6 girls) were analyzed. Family history, pregnancy and delivery did not reveal any significant anomalies. Birth length was 44.0 +/- 3.0 cm (boys) and 43.8 +/- 2.1 cm (girls), birth weight 2.0 +/- 0.4 kg and 2.05 +/- 0.3 kg, respectively. At the time of diagnosis (mean age 4.1 +/- 2.2 years), height was -4.4, bone age -1.9, weight -3.7, and head circumference -1.5 standard deviations below the normal mean for age. Calculated or reached adult height corresponded to 82--94% of target height. Intelligence was normal in most patients. 8 had asymmetrical extremities, 3 an asymmetrical face. 7 of 14 boys had cryptorchidism (3 uni-, 4 bilateral), 2 incomplete masculinization, and 2 of 6 girls hypertrophy of the clitoris. Development of secondary sex characters was appropriate for bone age with exception of one boy, whose puberty was early. In 3 boys with completed pubertal development, testicular volume was small and gonadotropins (before and after LHRH) high. It is concluded that 1. the growth pattern in Silver-Russell syndrome is quite homogeneous, and rather accurate predictions are possible; 2. Intersexual genitalia do not seem to be related to endocrine factors, and 3. hypergonadotropic hypogonadism appears to be frequent in males.
Testicular volume and function in adolescence after breech delivery.
Testicular volume and pubertal development were investigated in 108 boys born by breech delivery aged 14 1/2 to 19 1/2 years. Mean testicular volume was slightly but not significantly lower than in a control group of the same age. Pubertal development was normal. One boy had unilateral and two boys bilateral testicular atrophy (one with azoospermia and one with oligospermia). In a control group of 135 boys delivered from vertex position ther were three cases with unilateral and none with bilateral testicular atrophy. In both groups all cases with unilateral testicular atrophy could be explained by postnatal testicular injury, whereas the two cases of bilateral atrophy in the group of breech delivered boys remained unexplained. They may have originated from local trauma during breech delivery. It is concluded that testicular atrophy as a complication of breech delivery is seen with a frequency of only 2% or less.
Genetic mapping of the 21-hydroxylase-deficiency gene within the HLA linkage group.
To document further the proposed genetic linkage between congenital adrenal hyperplasia due to 21-hydroxylase deficiency and HLA, 34 unrelated families from New York and Zurich, with a total of 48 patients, 48 siblings and their parents, were studied. All patients were HLA genotypically different from the healthy sibs; when two or more children were affected in the same sibship they were always HLA-B identical. The gene for 21-hydroxylase deficiency was separated by genetic recombination from the HLA-A locus and from the locus for glyoxalase I-polymorphism. No HLA-A, HLA-B or HLA-C antigen was selectively increased among the 34 unrelated patients. Lod-score analysis for HLA-B:21-hydroxylase deficiency gave a peak for theta approximately 0.00 at 5.20 for females and 4.30 for males, giving a total peak lod score of 9.5 at theta approximately 0.00 when male and female lod scores were combined. Close genetic linkage between HLA-B and 21-hydroxylase deficiency was thus established.
[Development of intestinal and bladder control from birth until the 18th year of age. Longitudial study].
The development of bowel and bladder control from 0 to 18 years of age in 321 Swiss children of the Zurich Longitudinal Study (1955-1976) is described. 3% of the children had started toilet training by the age of 1 month and 96% by 12 months. Bowel control was completed in 32% at age one, in 75% at age two and in 97% at age three. Complete bladder control by day and at night was established in none of the children at age one, in 20% at ages two and three and in 90% at age five. About one quarter of the boys and one tenth of the girls had a period of incomplete bowel or bladder control between 6 and 18 years. During the prepubertal period, the annual incidence of enuresis was 7-15% in boys and 7-10% in girls, and that of encopresis 2-4% and 1-2% respectively. Some combination of enuresis diurna, enuresis nocturna and encopresis were found in 7% of all children, although in most children, these events did not occur simultaneously. With the exception of primary diurnal enuresis, the different types of enuresis and encopresis were more frequent in males than in females. By the onset of puberty, encopresis resolved in all children and enuresis persisted in only a few children. The role of toilet training and the etiologies and pathogenesis of enuresis and encopresis are discussed from a development point of view.
Bayley-Pinneau, Roche-Wainer-Thissen, and Tanner height predictions in normal children and in patients with various pathologic conditions.
Bayley-Pinneau, Roche-Wainer-Thissen, and Tanner height predictions at various chronologic ages were compared with final adult height in 56 normal subjects and in 34 patients with abnormal growth pattern (11 with familial tall stature, 7 with idiopathic precicious puberty, 6 with Turner syndrome, and 10 with primordial small stature or Silver-Russell syndrome). The two recent methods (Roche-Wainer-Thissen and Tanner) gave very accurate results and were superior to the Bayley-Pinneau method in normal subjects and in patients with familial tall stature. However, they overestimated adult height grossly in precocious puberty and moderately in Turner syndrome and in primordial small stature. It is concluded that calculations based on coefficients and regression equations obtained from normal children (as in the Roche-Wainer-Thissen and Tanner methods) can only be used in normal children or in patients with normal growth potential under adequate treatment. Calculations based on percentages of adult height (as in the Bayley-Pinneau method) are preferable in conditions in which the growth potential in relation to bone maturation is inherently reduced and cannot be corrected by treatment.
Analysis of the adolescent growth spurt using smoothing spline functions.
Height growth velocity curves between 4.5 and 17.75 years were estimated, using smoothing spline functions, for 112 boys and 110 girls from the Zurich Longitudinal Study (1955--1976). Parameters characterizing the growth process, such as peak height velocity and age at peak height velocity, were calculated directly from the estimated curves. The variability of parameters describing the adolescent growth spurt is large, both between and within sexes. Peak height, defined as increase of height velocity during the growth spurt, and age at peak height velocity both characterize the sex difference in growth in a highly significant manner. Peak height of at least 4 cm/year is found in 70% of the boys, but in only 11% of the girls. The age at peak height velocity averages 12.2 years in girls and 13.9 years in boys and has a wide range of 5.7 years and 3.8 years respectively. The sex difference in adult height of 12.6 cm is composed of the following 4 factors: +1.6 cm caused by more prepubertal growth in boys, +6.4 cm by the boys' delay in spurt, +6.0 cm by the more extensive spurt in boys and -1.4 cm by more post-spurt growth in girls. Correlations between parameters indicate that the adult height depends neither on the duration of growth, nor on the duration and height of the peak. Minimal pre-spurt height velocity and peak height velocity, but not peak height, are age- and height-dependent. Partial correlations given adult height reveal two compensating mechanisms between growth in the prepubertal and in the pubertal period. Small prepubertal height and low height velocity with respect to adult height are followed by a late adolescent spurt and vice versa. Small height at the onset of the spurt with respect to adult height is followed by a longer lasting, but not higher spurt and vice versa.
Endocrine studies in Fanconi's anaemia. Report of 4 cases.
Four boys with Fanconi's anaemia and growth hormone (GH) deficiency are reported. Case 1 had isolated GH deficiency and responded to HGH and to oxandrolone treatment. Case 2, his brother, had milder haematological and dysmorphic manifestations and maintained a low-normal growth rate without treatment in spite of laboratory evidence of GH deficiency. Case 3 had multiple hypothalamopituitary defects, including deficiencies of GH, ACTH, and gonadotrophins. Case 4 had isolated GH deficiency and responded moderately well to HGH treatment. 3 of the 4 patients had bilateral cryptorchidism, 2 with increased plasma gonadotrophins, indicating primary testicular failure. We conclude that GH deficiency, isolated or combined with other hypothalamopituitary defects, and primary testicular failure with cryptorchidism are frequent but not constant features of Fanconi's anaemia.
Pseudohypoparathyroidism and idiopathic hypoparathyroidism: relationship between serum calcium and parathyroid hormone levels and urinary cyclic adenosine-3',5'-monophosphate response to parathyroid extract.
Forty patients with hypocalcemia and/or Albright's hereditary osteodystrophy were studied. Based on the estimation of serum calcium and parathyroid hormone (PTH) levels as well as the urinary cAMP response to infusions with parathyroid extract, it was possible to classify all of the patients studied as cases with idiopathic hypoparathyroidism (n = 6, low PTH, normal cAMP response), pseudohypoparathyroidism (PHP) type I (n = 18, high PTH, low cAMP response) and type II (n = 2, high PTH, normal cAMP response), as well as pseudopseudohypoparathyroidism (n = 14, normal PTH, normal cAMP response). In three cases studied at the age of 12, 17, and 23 yr, the signs of Albright's hereditary osteodystrophy were not observed. PTH levels were unusually high for a given serum calcium concentration in some patients with PHP, the increased PTH levels were, however, normalized during iv calcium infusions. In two young children with PHP, a gradual increase of serum PTH levels occurred despite persistent normocalcemia over a period of 3 yr. This suggests that factors other than hypocalcemia or frequent small unobservable falls of the serum calcium concentration, such as a deficient formation of 1,25-dihydroxyvitamin D3, secretion of an abnormal PTH, or an abnormal metabolism of the hormone, may contribute to the secondary hyperparathyroidism in PHP.
Unusual heterozygotes of congenital adrenal hyperplasia due to 21-hydroxylase deficiency.
Three otherwise healthy relatives of patients with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency and salt-wasting presented with clinical and/or biochemical findings, which exceeded those usually seen in heterozygotes: Two females (1 mother and 1 prepubertal sister of a patient with CAH) had marked hypertrichosis and hirsutism and excreted pregnanetriolone in their urine. The mother had increased basal plasma 17alpha-OH-progesterone (296 ng/100 ml), which increased to 7170 ng/100 ml after ACTH as in homozygotes of CAH. One adult male (brother of a patient with CAH) was clinically normal, but also excreted pregnanetriolone and had a high plasma 17alpha-OH-progesterone (1905 ng/100 ml), which increased further to 6352 ng/100 ml after ACTH. It is concluded that these subjects represent unusually marked heterozygotes of CAH rather than mild homozygotes. In females, this condition should be included in the differential diagnosis of idiopathic hirsutism, in males, it will pass unnoticed, unless relatives of patients with CAH are systematically tested.
Treatment of excessively tall girls and boys with sex hormones.
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