Pubertal development in the Prader-Labhart-Willi syndrome.

The sexual maturation in the Prader-Labhart-Willi (PLW) syndrome was investigated in 14 patients, 10 females and 4 males. A wide variability in the pattern of pubertal development was found including delayed puberty in 5 patients and normal puberty in 4 patients; sexual precocity was also observed in 5 patients, true precocious puberty in one patient and incomplete sexual precocity in the form of precocious pubarche in 4 patients. In 5 patients, 3 of them with precocious pubarche, the appearance of the pubertal signs was followed by a delay or arrest in their future development. An LH-RH stimulation test was performed in 11 patients. In the 6 patients who eventually developed normal puberty, the basal levels and the peak responses of both LH and FSH were within the range of those observed in normal controls of the same pubertal stage. In 4 patients showing marked delay or arrest of puberty, the basal levels were normal or low and the responses of LH and FSH to LH-RH were blunted. Priming with repeated LH-RH stimulation in one of the male patients led to an augmented LH response, suggesting a hypothalamic hypogonadotrophism. It is concluded that the lack of uniformity in the pattern of sexual maturation in the PLW syndrome is due to a variability in the location and extent of a hypothalamic lesion, which may comprise an active process continuing beyond the perinatal period.     

Pituitary height and neuroradiological alterations in patients with Prader-Labhart-Willi syndrome

Prader-Willi syndrome (PWS), a genetic disorder due to an alteration in the paternally derived long arm of chromosome 15, is characterized by a complex clinical picture (short stature, obesity, hypogonadism) that seems to be referable to as a central hypothalamic/pituitary dysfunction. To determine whether there is any diminution in the anterior pituitary gland or other neuroradiological alterations, we retrospectively analysed 91 patients with PWS (42 females, 49 males; age range: 0.7–16.8 years) by cerebral magnetic resonance imaging (MRI). Of these 91 patients, MRI analysis showed a reduction in pituitary height in 45 patients (49.4%), a complete absence of the posterior pituitary bright spot in six patients (6.6%) and other neuroradiological alterations in ten patients (11%). Altogether, neuroradiological alterations were present in 61 of the 91 (67%) patients. Our results indicate that neuroradiological alterations are more frequent in PWS patients than has been reported to date.     

Primary gonadal failure and precocious adrenarche in a boy with Prader-Labhart-Willi syndrome

A 7-year-old boy with Prader-Labhart-Willi syndrome who had precocious adrenarche was found to have primary gonadal failure, as evidenced by appropriate laboratory investigations: elevated basal levels of plasma FSH and LH with exaggerated responses to LH-RH stimulation and unresponsiveness of plasma testosterone to repeated hCG stimulations. The elevated values of plasma DHEA which were found indicate an early activation of the adrenal gland. This patient demonstrates the varibility of pubertal development in the Prader-Labhart-Willi syndrome, with the unusual association of primary gonadal failure and precocious adrenarche.     

Low insulin, IGF-I and IGFBP-3 levels in children with Prader-Labhart-Willi syndrome

It is well established that insulin-like growth factor I (IGF-I), insulin-like growth factor binding protein-3 (IGFBP-3) and insulin are low in growth hormone deficiency, but due to their dependence on nutrition, they are elevated in healthy obese children. As the presence of growth hormone deficiency in Prader-Labhart-Willi syndrome (PWS) is still controversial, we studied insulin, IGF-I and IGFBP-3 levels in 19 children with PWS (age range 0.5–14.6 years). Serum concentrations of insulin (SDS: −0.7±0.9, P=0.01) and IGF-I (SDS: −0.7±0.8,P=0.002) were low, but IGFBP-3 (SDS: −0.3±1.2, P=0.2) was normal compared to normal weight age-matched children. Since children with PWS are typically obese, insulin, IGF-I and IGFBP-3 levels should be compared to normal obese children who present increased levels of these hormones. In comparison to data of healthy obese children reported in the literature, not only IGF-I, but also IGFBP-3 levels are low and fasting insulin levels even very low, suggesting a growth hormone deficiency. Received: 19 November 1997 / Accepted in revised form: 2 March 1998     

Premature adrenarche, increased growth velocity and accelerated bone age in male patients with Prader-Labhart-Willi syndrome

Premature adrenarche/pubarche in male patients with Prader-Labhart-Willi syndrome may be associated with increased growth velocity and bone age acceleration.     

Ortner syndrome in infants

Ortner syndrome or cardiovocal syndrome refers to hoarseness of voice due to recurrent laryngeal nerve paralysis secondary to cardiovascular disease. We present three cases of Ortner syndrome in infants with congenital heart disease. All the three cases had moderate to severe pulmonary hypertension with moderately dilated pulmonary artery. We believe that the dilated pulmonary artery caused compression of the left recurrent laryngeal nerve resulting in hoarseness of voice.     

Superior vena cava syndrome in infants

Superior vena cava syndrome is uncommon in infants. With the increased use of central venous catheters, however, there has been an increased incidence of central venous occlusion. We report a case of superior vena cava syndrome occurring on two separate occasions in a premature infant with an indwelling central line. We discuss current concepts of prevention and management.     

Ovarian hyperstimulation syndrome in preterm infants

Estradiol-producing ovarian cysts were found in four very preterm females at a postconceptional age that slightly preceded the expected time of delivery. The serum concentration of estradiol was very high. In the first infant one cystic ovary was removed surgically. When cysts appeared in the other ovary, the girl was treated with medroxyprogesterone acetate. The serum concentration of estradiol then fell and the cysts disappeared. Medroxyprogesterone acetate treatment was given also to the second girl, who had a high and rising serum concentration of estradiol. In infants 3 and 4 the cysts disappeared and the serum estradiol normalized spontaneously. Measurements of serum concentrations of luteinizing hormone and follicle-stimulating hormone before and after an iv injection of luteinizing hormone releasing hormone showed that preterm girls with early estradiol-producing ovarian cysts have a postpubertal type of response to luteinizing hormone-releasing hormone. When the test is repeated some months later they have a prepubertal type of response, which is normal for their age.