Hyponatraemia associated with lamotrigine in cranial diabetes insipidus

We report the cases of two children with cranial diabetes insipidus who were treated with lamotrigine for seizures and who had accompanying changes in desmopressin requirements. Lamotrigine is a new anticonvulsant chemically unrelated to other existing antiepileptic drugs. Studies suggest it acts at voltage-sensitive sodium channels and also decreases calcium conductance. Both of these mechanisms of action are shared by carbamazepine, which can cause hyponatraemia secondary to inappropriate secretion of antidiuretic hormone. It is possible that the effect of lamotrigine on fluid balance in the cases described is also centrally mediated.

Growth hormone treatment of Russell-Silver syndrome

Russell-Silver syndrome represents a special group of children with intrauterine growth retardation (IUGR) who do not experience catch-up growth and have characteristic dysmorphic features. They also have characteristics of abnormal growth hormone pulsatility, absence of catch-down growth after growth hormone therapy and inappropriate advancement of bone age during the middle childhood years. Data from children with Russell-Silver syndrome should certainly be analysed as a separate group from short children due to nondysmorphic IUGR. Initial data suggests that final height outcome will be improved by using pharmacological doses of biosynthetic human growth hormone. Indeed, the recent data supports the hypothesis of Blizzard's group in 1974 that if growth hormone became available in sufficient quantities, then final height could be altered in IUGR children. In addition, the early recognition and treatment of spontaneous nocturnal hypoglycaemia may well improve the educational achievement of such children.

Occult T3 toxicosis in McCune-Albright syndrome

We report a girl with McCune-Albright syndrome who presented with Cushing syndrome from adrenal hypersecretion and gonadotrophin-independent precocious puberty in the first year of life. At age 5, she failed to gain weight and was found to have hyperthyroidism, which was occult in that she had T3 toxicosis without a goitre or thyroid ultrasound abnormality. The latter has not been previously reported in McCune-Albright syndrome.

Absence of catch-down growth in Russell-Silver syndrome after short-term growth hormone treatment

We describe 3 children with Russell-Silver syndrome without growth hormone insufficiency who were treated with growth hormone for 2, 3. 7 and 6 years, showing a rapid growth acceleration. After cessation of growth hormone treatment, they grew at a normal rate without 'catch-down' growth. It may be possible that short intra-uterine growth retardation (IUGR) children with dysmorphic features respond to growth hormone therapy differently from non-dysmorphic IUGR short children. Short-term growth hormone treatment for children with Russell-Silver syndrome may avoid side effects and diminish costs.

Growth hormone treatment in growth hormone-sufficient and -insufficient children with intrauterine growth retardation/Russell-Silver syndrome

Fifty-eight short prepubertal children with IUGR received GH treatment (mean dose: 28 IU/m2/week) for a mean (SEM) period of time of 3.4 (0.13) years (range 1-4 years). They were subdivided according to their GH response to a pharmacological test. Twenty-six were GH insufficient (GHI) (group 1) and 32 were non-GHI (group 2). At the commencement of GH therapy mean chronological age was 6.1 (0.4) years in both groups, mean height SDS (SEM) was -3.5 (0.2) in group 1 and -3.6 (0.2) in group 2, mean growth velocity (GV) SDS (SEM) was -1.9 (0.3) in group 1 and -0.3 (0.2) in group 2. GH therapy induced significant growth acceleration throughout the follow-up period without any significant differences between the two groups. GV SDS (SEM) increased to +3.0 (0.5) in group 1 and to +3.7 (0.4) in group 2 (p < 0.05 compared to baseline) during the first year of therapy. Subsequently, the growth-promoting effects of GH therapy diminished with time but GV remained significantly higher than baseline. This growth enhancement produced a significant rise in height SDS (SEM) reaching - 1.4 (0.2) in group 1 and - 1.7 (0.2) in group 2 after 4 years. In conclusion, our data did not show any significant differences in the growth response to GH therapy between GH-sufficient and -insufficient IUGR children who were only distinguishable by their GH secretion. This indicates that the decision to treat a short IUGR child with GH therapy should not be based upon the GH response to a provocative test.

Premature thelarche: clinical follow-up and indication for treatment

Not only is the diagnosis of isolated premature thelarche difficult to distinguish from other variants of premature sexual maturation, but within the subgroups of isolated premature thelarche, there are probably at least two subgroups: "classical" and "atypical". We do not appreciate how potential treatment could affect each group, although it seems likely that those in the "classical" group would not have an indication for treatment. The longer-term follow-up of large numbers of patients is essential if we are to understand the long-term sequelae of this condition.

Basilar invagination as a sequela of multisystem Langerhans' cell histiocytosis

We report the presence of basilar invagination, an unexpected and previously undescribed abnormality of the skull base, in 7 of 38 long-term survivors of multisystem Langerhans' cell histiocytosis. The abnormality is acquired, but its pathogenesis is uncertain.

Sexually dimorphic and radiation dose dependent effect of cranial irradiation on body mass index

OBJECTIVES

To investigate the relation between cranial irradiation received during treatment for childhood leukaemia and obesity at final height.

DESIGN

Retrospective cross sectional study.

SETTING

Paediatric oncology centres at Great Ormond Street Hospital for Children and the Royal Marsden Hospital.

SUBJECTS

Survivors of childhood leukaemia who received cranial irradiation, were in continuous first remission, and had reached final height. An unirradiated group of patients from the United Kingdom acute lymphoblastic leukaemia XI trial was also included; these patients were in continuous first remission and had been followed for at least four years from diagnosis.

MAIN OUTCOME MEASURES

Body mass index standard deviation score (BMI z score) at final height for irradiated patients and at most recent follow up for unirradiated patients. Regression analysis was used to examine the effect on BMI z score of sex, age at diagnosis, and the dose of radiation received.

RESULTS

For cranially irradiated patients, an increase in the BMI z score at final height was associated with female sex and lower radiation dose, but not with age at diagnosis. Severe obesity, defined as a BMI z score of > 3 at final height, was only present in girls who received 18-20 Gy irradiation and had a prevalence of 8%. Both male and female unirradiated patients had raised BMI z scores at latest follow up and there was no association with age at diagnosis.

CONCLUSIONS

These data are further evidence for a sexually dimorphic and dose dependent effect of radiation on the human brain.

The spectrum of Silver-Russell syndrome: a clinical and molecular genetic study and new diagnostic criteria

The Silver-Russell syndrome (SRS) is characterised by severe intrauterine growth retardation, with a preserved head circumference, leading to a lean body habitus and short stature. Facial dysmorphism and asymmetry are considered typical features of the syndrome, although the range of phenotypic variance is unknown. Fifty seven subjects varying in age from 0.84 to 35.01 years, in whom the diagnosis of SRS had been considered definite or likely, were re-evaluated in a combined clinical and molecular study by a single observer (SMP). In 50 patients the clinical findings complied with a very broad definition of SRS. Notable additional findings included generalised camptodactyly seen in 11 (22%), many with distal arthrogryposis. Thirteen of the 25 males required genital surgery for conditions including hypospadias and inguinal hernia. Fourteen (36.8%) subjects above school age have received a statement of special educational needs. Molecular genetic analysis was performed in 42 subjects and has identified maternal uniparental disomy of chromosome 7 in four. The phenotype was generally milder with birth weights for one patient above and three below -2 SD from the mean. Two children had classical facial dysmorphic features, and two had a milder facial phenotype. Of relevance to the possible molecular mechanism underlying this condition, none of the four disomic patients had significant asymmetry.

Lipid profile, glucose tolerance and insulin sensitivity after more than four years of growth hormone therapy in non-growth hormone deficient adolescents

OBJECTIVE

To study the effects of long-term (> 4 years) growth hormone (GH) therapy on insulin sensitivity, glucose tolerance and lipid profile in non-GH deficient adolescents at completion of their growth.

SUBJECTS

Thirty non-GH deficient (15 'idiopathic' short stature, 8 intrauterine growth retardation, 7 partial GH deficiency in childhood but normal on retesting) were recruited, median (range) age 16.9 years (15-20.3) prior to ceasing their GH therapy. Their median (range) duration of GH treatment was 7.9 years (4-11). Insulin sensitivity was also recorded in 10 normal controls with a median (range) age of 20.5 years (18.4-22.3).

METHODS

Insulin sensitivity was assessed by a short insulin tolerance test in 18 patients on GH therapy and controls. It was repeated in 14 patients six months after stopping their GH therapy. A 3-h standard oral glucose tolerance test (OGTT) was performed in 19 patients on GH therapy, and repeated after 6 months off GH in 10 patients. Fasting lipids were also measured.

RESULTS

Insulin sensitivity index was significantly lower in the patients on GH therapy than in the controls, (median (range)) 3.7%/min (1.2-5.3) and 5.3%/min (3.8-6.2), respectively. Six months after termination of GH therapy, insulin sensitivity increased significantly from 3.6%/min (1.2-5) to 4. 8%/min (2.8-5.6). Fasting plasma insulin decreased significantly off GH therapy from 10.1 to 3.6 mU/l. The area under the insulin curve during the OGTT was also significantly higher on GH therapy. Apart from one patient with impaired glucose tolerance on GH treatment, plasma glucose concentrations remained within the normal range. No lipid abnormalities were recorded.

CONCLUSIONS

These data suggest that long-term GH therapy may cause insulin resistance in non GH deficient adolescents, but usually with neither impaired glucose tolerance nor hyperlipidaemia.

Multiple neonatal endocrinopathies in McCune-Albright syndrome

Two cases of McCune-Albright syndrome (MAS) are reported who presented in the neonatal period with profound failure to thrive, cardio-respiratory distress, precocious puberty and Cushing's syndrome for which both underwent bilateral adrenalectomy. Both girls had also bilateral nephrocalcinosis; in one case that may have been attributed to Cushing's syndrome, but in the second case the cause remained obscure with no obvious abnormality of calcium metabolism. The first girl had hydrocephalus which is uncommon in this condition and the second girl still failed to thrive at the age of 6 years, despite adequate caloric intake and hormonal manipulation. A constellation of other abnormal features are described. These cases illustrate the complexity of MAS which can become a life-threatening or a debilitating disorder.

Growth failure and pituitary function in CHARGE and VATER associations

Growth failure and anterior pituitary dysfunction are clinical features of the CHARGE and VATER associations. This study investigated pituitary dysfunction as a potential cause of poor growth in a series of four and three patients with the CHARGE and VATER associations, respectively, who had height standard deviation scores (SDS) less than-2. Five of the seven patients had associated subnormal growth velocity SDS. Patients were investigated with a combination of dynamic and basal endocrine tests. All patients were found to be normonatraemic and to have normal basal thyrotroph and stimulated corticotroph function. The one peripubertal patient had evidence of biochemical gonadotroph dysfunction. Although two patients had marginally low stimulated serum growth hormone responses to glucagon stimulation testing, this was associated with either normal growth velocity or normal serum insulin-like growth factor binding protein 3 (IGFBP-3) concentrations. Thus, somatotroph dysfunction could not be demonstrated unequivocally in any patient. Poor childhood linear growth in the CHARGE and VATER associations does not appear to be associated with pituitary dysfunction.

Pituitary dysfunction, morbidity and mortality with congenital midline malformation of the cerebrum

The purpose of this study was to review systematically a series of patients with congenital midline brain defects and pituitary dysfunction in early childhood and to quantitate the degree of dysfunction and clinical outcome. This study was a retrospective analysis of case notes of patients with pituitary dysfunction associated with either a midline cerebral anomaly and/or optic nerve hypoplasia. Forty patients were studied: 2 with semilobar holoprosencephaly, 2 with lobar holoprosencephaly, 18 with septo-optic dysplasia with an intact septum pellucidum, 7 with septo-optic dysplasia with an absent septum pellucidum, 7 with agenesis of the corpus callosum and 4 patients with isolated pituitary hypoplasia. An early age of diagnosis, feeding difficulties, neurodevelopmental disability, visual impairment and seizures were common occurrences. Despite disordered neuro-anatomy, most seizure disorders were caused by hypoglycaemia or hypernatraemia. Hypotensive/hypoglycaemic crises accounted for two out of three deaths within the study population. Most of patients had multiple pituitary hormone deficiency with growth hormone and adrenocorticotrophic hormone deficiency occurring most commonly. Unequivocal isolated hypothalamic dysfunction was an uncommon finding. In congenital midline brain malformation there is a spectrum of disordered neuro-anatomy associated with variable pituitary dysfunction. Clinical manifestations such as convulsions and developmental delay may be due to disordered metabolism and/or neuro-anatomy.

CONCLUSION

Children with congenital midline brain defects frequently manifest convulsions, neurodevelopmental disability and poor growth due to disordered metabolism and/or neuro-anatomy. Treating clinicians must be aware of the complex, dynamic neurological and metabolic nature of these patients and their potential for early demise.

Why is the retention of gonadotrophin secretion common in children with panhypopituitarism due to septo-optic dysplasia?

Septo-optic dysplasia (De Morsier syndrome) is a developmental anomaly of mid-line brain structures and includes optic nerve hypoplasia, absence of the septum pellucidum and hypothalamo-pituitary abnormalities. We describe seven patients (four female, three male) who had at least two out of the three features necessary for the diagnosis of septo-optic dysplasia. Four patients had hypopituitarism and yet normal gonadotrophin secretion: one of these also had anti-diuretic hormone insufficiency; three had isolated GH deficiency and yet had premature puberty, with the onset of puberty at least a year earlier than would have been expected for their bone age. In any progressive and evolving anterior pituitary lesion it is extremely unusual to lose corticotrophin-releasing hormone/ACTH and TRH/TSH secretion and yet to retain gonadotrophin secretion. GnRH neurons develop in the nasal mucosa and migrate to the hypothalamus in early fetal life. We hypothesise that the arrival of GnRH neurons in the hypothalamus after the development of a midline hypothalamic defect may explain these phenomena. Progress in spontaneous/premature puberty in children with De Morsier syndrome may have important implications for management. The combination of GH deficiency and premature puberty may allow an apparently normal growth rate but with an inappropriately advanced bone age resulting in impaired final stature. GnRH analogues may be a therapeutic option. In conclusion, some patients with De Morsier syndrome appear to retain the ability to secrete gonadotrophins in the face of loss of other hypothalamic releasing factors. The migration of GnRH neurons after the development of the midline defect may be an explanation.

Metaphyseal growth arrest lines in psychosocial short stature

Metaphyseal growth arrest lines are seen in children who experience significant physical stress such as infection or malnutrition over a sufficient period of time. These lines have not been reported previously in children with psychosocial short stature (PSS). Two boys and a girl with PSS with metaphyseal growth arrest lines on skeletal radiographs at the time of maximal stress in their homes are described. All three had reversible growth hormone insufficiency during admission, which is pathognomic for PSS. Multiple growth arrest lines in the distal end of the radius or vertebrae should alert clinicians to an alternative diagnosis in a child with growth hormone insufficiency. This may provide a clue to the diagnosis of occult PSS.

Recognition of children with psychosocial short stature: a spectrum of presentation

We describe 65 children (32F, 33M) with psychosocial short stature from 51 families. Average age was 6.6 years (range 0.9-16.5) and all but five were prepubertal. 67% of the patients lived in families with three or more children, but in 73% of cases the patient was the first or the second born child. 45% of the parents were divorced and in 31% of the families the father was unemployed. In 56 children, the birth weight was known and in only 29% was it above 3000 g; 21% were premature, 29% had features of low birth-weight syndrome (including four with Russell-Silver syndrome). Average birth weight was 2786 g (range 1650-4676). In all patients, the predominant reason for referral was growth failure. In 28% an environmental aetiology was suspected and in a further 29%, social or emotional problems were known to the referring physician but not suspected as the aetiology of the growth failure, despite social services involvement in 60% at the referral to our unit. At initial presentation in our clinic, we found additional features leading to the suspicion of psychosocial short stature; 54% abnormal eating pattern, 42% behaviour problems, 26% encopresis, 18% nocturnal enuresis and 12% inappropriate urination. During the observation period of a mean of 3.7 years, 27 (41%) of our patients were found to have been sexually or physically abused. In these 27 children hyperphagia, bizarre eating habits, behaviour problems, soiling and nocturnal enuresis were more common.

Frontonasal dysplasia with optic disc anomalies and other midline craniofacial defects: a report of six cases

The association of optic disc abnormalities with basal encephaloceles, specifically of the sphenoethmoidal type, and midline facial clefts has rarely been reported, although the association of midline facial clefts with encephaloceles is well described. We now report six cases of children, three males and three females, presenting with a sphenoethmoidal encephalocele, optic disc anomalies, midline facial clefting, hypertelorism, complete or partial agenesis of the corpus callosum, and endocrinological disturbances, including diabetes insipidus and pituitary dysfunction. This report underlines the importance of careful ophthalmic and endocrinological investigation of children with midline clefts associated with basal encephaloceles. These cases may represent a distinct entity within the spectrum of frontonasal dysplasia.

GH treatment induces sustained catch-up growth in children with intrauterine growth retardation: 7-year results

The anthropometric response to 7 years of GH treatment was assessed in 11 short children with Russell-Silver syndrome (RSS) and in 5 with non-dysmorphic intrauterine growth retardation (NRSS). GH treatment induced a significant increase (p < 0.0001) in the mean height standard deviation score (SDS) and at the 7-year follow-up a height appropriate for the natural history of final stature in NRSS/RSS was already attained. An appreciable growth rate was still present with final height being attained only in 2 girls. There was no significant change in height SDS for bone age. Multiple regression analysis showed only chronological age at the onset of GH treatment was a predictor of gain in height SDS during GH therapy. These findings suggest that early GH treatment improves long-term growth in children with NRSS/RSS. Moreover, final height attainment is required for a definitive assessment of the beneficial effect on adult stature. Bone age assessment is not a reliable parameter to predict final height outcome in these children.

Precocious pseudopuberty due to a granulosa cell tumour in a seven-month-old female

We describe a juvenile granulosa cell tumour resulting in pseudopuberty in an infant female. The progression of the clinical signs of puberty were non-consonant and the diagnosis was complicated by marginally elevated serum alpha-fetoprotein levels. The histological appearance of the resected tumour and binding of MIC2 antibody to tumour cells confirmed the diagnosis.