Long-term evolution of endocrine disorders and effect of GH therapy in 35 patients with pituitary stalk interruption syndrome

We report long-term evolution of endocrine functions and the results of GH treatment in 35 patients (26 male and 9 female) with pituitary stalk interruption. At diagnosis, mean chronological age was 4.8 +/- 2.7 years, mean SDS for height -3.1 +/- 0.8 with a bone age retardation of 2.3 +/- 1.3 years and a mean SDS for growth velocity of -0.5 +/- 1.1; 80% presented complete GH deficiency (GHD) and 20% partial GHD; thyroid deficiency was present in 47.1% of children with complete GHD but absent in all partial GHD. Diagnosis was made during the first months of life in only 2 patients while 23% presented with severe neonatal distress; neonatal signs were only observed in the group with pituitary height below 2 mm (45.7% of patients). GHD was isolated in 40.6% of patients below 10 years while multiple hormone deficiencies was consistent at completion of growth in all patients. Height gain was significantly higher in patients who started GH treatment before 4 years (p = 0.002). GH treatment is very effective: in 13 patients, final height was -0.4 +/- 1.0, total height gain 3.2 +/- 1.2 and distance to target height -0.3 +/- 1.6 SDS.     

Eventos adversos perinatales y anomalías neuroanatómicas en pacientes con hipopituitarismo idiopático

ObjectiveTo analyze the possible causes of growth hormone (GH) deficiency, whether isolated (GHD) or in combination with other pituitary deficiencies classified as idiopathic.Patients and methodsWe studied patients with idiopathic GHD included in a protocol of recombinant GH treatment in adults attending the outpatient clinic of the Endocrinology and Nutrition Service of the San Cecilio University Hospital. Perinatal history, findings on magnetic resonance imaging (MRI) of the hypothalamic-pituitary axis and diagnosis of GHD and other deficiencies were retrospectively evaluated.ResultsA total of 17 patients were included: 14 men and 3 women with a mean age at diagnosis of 8.4±7.3 years. Perinatal adverse events occurred in 12 patients (69.2%). MRI showed empty sella (2 patients), pituitary hypoplasia or absence of the pituitary stalk (7 patients) and pituitary hypoplasia with ectopic posterior pituitary gland (6 patients); in the remaining 2 patients these data were not available. All had an established diagnosis of GHD: 15 with (88.2%) gonadotropin deficiency, 9 (52.9%) with adrenocorticotropic hormone (ACTH) deficiency and 8 (47.1%) with thyroid-stimulating hormone (TSH) deficiency.ConclusionsIn our patients, adverse events during pregnancy or the perinatal period and the presence of anatomical abnormalities identified by MRI are a marker of pituitary dysfunction and may be important in the pathogenesis of this entity. The clinical spectrum of disease varies from isolated GH deficiency to multiple pituitary hormone deficiencies.     

Children with isolated growth hormone deficiency: Empty sella versus normal sella

BACKGROUND:

Empty sella (ES) may be associated with variable clinical conditions ranging from the occasional discovery of a clinically asymptomatic pouch within the sella turcica to severe intracranial hypertension and rhinorrhea. The need for replacement hormone therapy in ES, as in other syndromes that may cause hypopituitarism, must be assessed for every single hormone, including growth hormone (GH).

AIM:

To determine whether or not the presence of ES could allow some changes in the GH responses of the isolated growth hormone deficiency (GHD) patients.

MATERIALS AND METHODS:

We included a cohort of 59 short stature children and adolescents with isolated GHD. According to computed tomography finding, they were classified into 2 groups: Group 1 included 40 children with normal sella and 19 children with ES in Group 2. All patients received recombinant human growth hormone (rhGH) with a standard dose of 20 IU/m²/week.

RESULTS:

The baseline results were not significantly different for all variables except weight standard deviation was smaller with statistical significant difference (P = 0.02). We identified no significant differences when comparing both groups, except for height standard deviation (HTSD) after the first year of therapy which revealed significant difference in favor of group 1. When comparing pre- and the two post-treatments HTSD results of the studied cases, all showed significant changes after GH therapy. The results of related variables pre-and post-treatment in both the groups showed significant improvement in all variables of the two groups of the study.

CONCLUSION:

Our study showed a similar stature outcome in the two treatment groups.     

Final height in children with idiopathic growth hormone deficiency treated with a fixed dose of recombinant growth hormone

There is no consensus regarding the optimal dosing of recombinant human growth hormone (rhGH) for children with growth hormone deficiency (GHD). Our objective was to evaluate the final adult height (FAH) in children with idiopathic GHD treated with a fixed rhGH dose of 0.18 mg/kg/week. We reviewed all charts of patients with idiopathic GHD treated with rhGH since 1985 who reached FAH. Ninety-six patients were treated for an average of 5.4 years. The mean age was 11.9 years, the mean height -2.87 standard deviation score (SDS) and the mean FAH was -1.04 SDS. Females had a lower predicted adult height than males at the initiation of therapy (-2.0 vs. -1.01 SDS; p = 0.0087) but a higher FAH - predicted adult height (1.08 vs. 0.04 SDS; p = 0.0026). In multiple regression analysis, the FAH SDS was positively related to the midparental height SDS, the height SDS at GH initiation and growth velocity during the first year of therapy, and negatively correlated with peak GH and bone age at initiation (r(2) = 0.51; p < 0.005). Treatment of children with idiopathic GHD with a fixed dose of 0.18 mg/kg/week rhGH is sufficient to reach FAH within 2 SDS of the normal population range (84%) with an average FAH within -0.5 SDS of midparental height.     

Total pubertal growth and markers of puberty onset in adolescents with GHD: comparison between mathematical growth analysis and pubertal staging methods

Two methods of determining puberty onset (Preece- Baines model 1 (PB1) and Tanner staging) were used to calculate total pubertal growth (TPG) in adolescents with growth hormone deficiency (GHD). PATIENTS AND METHODS: 34 patients (11 girls) met the following inclusion criteria: isolated GHD, >2 years growth hormone therapy prior to puberty onset, regular weight-adjusted GH dosage, known final height (age >21 years or height velocity <0.5 cm/year), no induction of puberty. PB1 was used to define age and height at onset of the pubertal growth spurt ("take-off"). RESULTS: The results (mean +/- SD) were as follows: in girls, mean age at take-off was 9.8 years; 2.0 +/- 1.1 years before breast stage B2. In boys, mean age at take-off was 11.3 years; 1.4 +/- 0.8 years before testes volume >3 ml. Height at take-off was lower than at Tanner stage 2 by 12.4 +/- 7.6 cm in girls and 7.7 +/- 5.3 cm in boys. TPG was thus markedly greater (p < 0.001) using the PB1 method, as compared with Tanner stage2. Peak height velocity was normal. Final height was -0.5 +/- 0.7 SDS in females and -0.4 +/- 0.9 SDS in males. CONCLUSIONS: The method of measuring TPG from take-off is more objective, and has potentially greater implications for GH therapeutics than the Tanner stage method. In our study, 40% of TPG occurred before "breast stage B2" was attained in GHD girls; whereas 23% of TPG occurred before "testes >3 ml" in GHD boys.     

Final height in children with idiopathic growth hormone deficiency treated with recombinant human growth hormone: the Belgian experience

BACKGROUND: The growth response to recombinant hGH (rhGH) treatment and final height of 61 Belgian children (32 boys) with idiopathic growth hormone deficiency (GHD) were studied. PATIENTS/METHODS: Two patient groups were compared: Group 1 with spontaneous puberty (n = 49), Group 2 with induced puberty (n = 12). The patients were treated with daily subcutaneous injections of rhGH in a dose of 0.5-0.7 IU/kg/week (0.17-0.23 mg/kg/week) from the mean +/- SD age of 11.9 +/- 3.1 years during 5.1 +/- 2.1 years. RESULTS: rhGH treatment induced a doubling of the height velocity during the first year and resulted in a normalisation of height in 53 (87%) patients. Final height was -0.7 +/- 1.1 SDS, being 170.4 +/- 7.2 cm in boys and 158.0 +/- 6.4 cm in girls. Corrected for mid-parental height, final height was 0.0 +/- 1.1 SDS. Ninety-two percent of the patients attained an adult height within the genetically determined target height range. Although height gain during puberty was smaller in the patients with induced puberty (boys: 17.1 +/- 7.0 cm vs. 27.5 +/- 6.6 cm (p < 0.005); girls: 9.6 +/- 7.4 cm vs. 22.2 +/- 6.1 cm (p < 0.005)), no differences in final height after adjustment for mid-parental height were found between patients with spontaneous or induced puberty. CONCLUSIONS: We conclude that patients with idiopathic GHD treated with rhGH administered as daily subcutaneous injections in a dose of 0.5-0.7 IU/kg/week reach their genetic growth potential, resulting in a normalisation of height in the majority of them, irrespective of spontaneous or induced puberty.     

Isolated thyrotropin deficiency due to a pituitary tumour.

Hypothyroidism due to isolated deficiency of thyrotropin (TSH) associated with an enlarged sella turcica, presumably the result of a nonfunctioning pituitary adenoma, occurred in a 58-year-old man. Low serum concentrations of TSH and thyroid hormones, together with the lack of TSH response to administration of thyroid releasing hormone, indicated a pituitary deficiency of TSH. Serum values of other pituitary hormones were normal.     

Long-Term GH therapy: epidemiology and auxologic outcome

OBJECTIVES: Epidemiologic and auxologic characteristics of patients treated with GH during childhood and adolescence and entered in a national registry in Catalonia were studied between 1988 and 1997. At the end of 1997, prevalence was 53.2 treatments/100,000 inhabitants aged 0-14 years. Maximum annual incidence rates were observed in 1990 and 1991 (34.0-35.6 cases/100,000 inhabitants aged 0-14 years). STUDY DESIGN: Analysis of treatments terminated in 1993 (n = 548) revealed, for the three principal reasons for cessation of treatment ('near-final height', 'adequate height but further growth potential', and 'poor growth response'), that males began and ended treatment at older ages with a better auxologic situation in SDS than girls at the beginning and end of therapy in the first two subgroups, with a similar duration of therapy. Severe GH deficiency (GHD) [both multiple pituitary hormone deficiency (MPHD) and the most severe isolated GHD (IGHD-A)] was more frequent in the group ending treatment at 'near-final height', whereas cessation of therapy because of 'poor growth response' was more frequent in the group with 'other causes of short stature' and no demonstrable GHD by routine tests. In the near-final height group, after excluding Turner's syndrome, MPHD and GHD cases secondary to brain tumors and GH deficiencies associated with malformative syndromes, positive linear correlations were observed between HSDS at the end of treatment and HSDS at the beginning, predicted adult height SDS (PAHSDS) and target height SDS (THSDS). Multiple regression analysis showed that in this group of patients, 41.4% of the variability in HSDS increment can be explained by the equation: HSDS increment = -0.33 + 0.29 THSDS - 0.68 HSDS at the beginning of treatment. RESULTS: The outcome showed a reasonable use of GH, since good-response cases generally continued treatment until final height whereas therapy was suspended in doubtful cases.     

Pituitary stalk interruption syndrome: diagnostic delay and sensitivity of the auxological criteria of the growth hormone research society

Objectives

To study the diagnostic delay for pituitary stalk interruption syndrome (PSIS) with growth hormone deficiency (GHD) and the sensitivity of the auxological criteria of the Growth Hormone Research Society (GHRS) consensus guidelines.

Methods

A single-center retrospective case-cohort study covering records from January 2000 through December 2007 evaluated the performance of each GHRS auxological criterion for patients with GHD and PSIS. Diagnostic delay was calculated as the difference between the age at which the earliest GHRS criterion could have been observed and the age at diagnosis of PSIS with GHD. A diagnostic delay exceeding one year was defined as late diagnosis.

Results

The study included 21 patients, 16 (76%) of whom had isolated GHD and 5 (24%) multiple pituitary hormone deficiencies. The median age at diagnosis was 3.6 years (interquartile range, IQR, 2.6–5.5). The median diagnostic delay was 2.3 years (range 0–12.6; IQR 1.5–3.6), with late diagnosis for 17 patients (81%). Height more than 1.5 SDS below target height was the most effective criterion: 90% of the patients met the criterion before diagnosis at a median age of 1 year, and it was the first criterion to be fulfilled for 84%.

Conclusion

In our cohort, the delay for diagnosis of PSIS with GHD was long and could have been reduced by using the GHRS criteria, in particular, height more than 1.5 SDS below the target height. The specificity of such a strategy needs to be tested in healthy populations.     

Empty sella in control subjects and patients with hypopituitarism

The frequency and distribution of various degrees of empty sellae have been examined in subjects without any pituitary disorder and in patients with hypopituitarism. Among them none had sellar enlargement. Sellar computed tomography (CT) with contiguous 2 mm slices (thickness in the axial projection) was performed in 56 control subjects. The CT findings on sella turcica were graded into 4 groups (0, 1+, 2+, and 3+), and grades 2+ and 3+ indicated moderate and marked empty sellae. Thirty-nine percent of the control subjects had empty sellae of grade 2+ or 3+. Sellar CT scans with contiguous 2 mm slices were also performed in 11 patients with hypopituitarism. The sellar volume ranged from 224 to 715 mm3. CT scan was carried out more than 2 years after the onset of hypopituitarism in 10 of 11 patients, and showed typical empty sellae of grade 3+ in all 10 patients. There was no empty sella in a patient with hypopituitarism whose CT scan was carried out 3 months after the massive postpartum hemorrhage. Our results indicate that moderate empty sella of grade 2+ can be seen in subjects without any pituitary disorder, and that a typical empty sella of grade 3+ is present in hypopituitarism with a normal sized sella turcica. An empty sella associated with hypopituitarism may be due to shrinkage of the pituitary gland related to its hypofunction.     

Depression,smoking, physical inactivity and season independently associated with midnight salivary cortisol in type 1 diabetes

Background

Trisomy 9p is an uncommon anomaly characterised by mental retardation, head and facial abnormalities, congenital heart defects, kidney abnormalities, and skeletal malformations. Affected children may also show growth and puberty retardation with delayed bone age. Auxological and endocrinological data are lacking for this syndrome.

Methods

We describe three girls and one boy with 9p trisomy showing substantial growth failure, and we evaluate the main causes of their short stature.

Results

The target height was normal in all families, ranging from 0.1 and -1.2 standard deviation scores (SDS). The patients had a low birth-weight (from -1.2 to -2.4 SDS), birth length (from -1.1 to -3.2 SDS), and head circumference (from -0.5 to -1.6 SDS). All patients presented with substantial growth (height) retardation at the time of 9p trisomy diagnosis (from -3.0 to -3.8 SDS). The growth hormone stimulation test revealed a classic growth hormone (GH) deficiency (GHD) in patients 1, 3, and 4. In contrast, patient 2 was determined to have a GH neurosecretory dysfunction (GHNSD). The plasma concentrations of IGF-I and IGFBP-3 were low in all patients for their ages and sexes (from -2.0 to -3.4 SDS, and from -1.9 to -2.8 SDS, respectively). The auxological follow-up showed that those patients who underwent rhGH treatment exhibited a very good response to the GH therapy, whereas patients 3 and 4, whose families chose not to use rhGH treatment, did not experience any significant catch-up growth.

Conclusions

GH deficiency appears to be a possible feature of patients with 9p trisomy syndrome. These patients, particularly those with growth delays, should be evaluated for GH secretion.     

Plasma growth hormone response to synthetic GH-RH1-44 in 52 children and adults with growth hormone deficiency of various etiologies

52 patients (42 children and 10 adults) with growth hormone deficiency (GHD), grouped into four diagnostic categories, and 6 children with constitutional short stature who served as controls were tested for plasma GH response to synthetic GH-RH1-44 given in an intravenous bolus. The response was classified into three degrees according to the magnitude of the maximal rise: Good, greater than 9 ng/ml; Partial, 3.1-9.0 ng/ml; None, less than or equal to 3 ng/ml. Among the GHD patients the highest response was observed in patients with partial growth hormone deficiency (PGHD), and 60% of the children with isolated GH deficiency (IGHD) showed an increase in plasma GH levels. Nevertheless, the response of the GHD patients was lower than that in the control group. In the children and adolescents with PGHD and IGHD the response was not age related. Among those with multiple pituitary hormone deficiencies-idiopathic (MPHD-ID) there was no response in the adolescents although a hypothalamic disorder had been documented by other tests. Among those with MPHD-organic (MPHD-ORG) the GH-RH stimulated GH secretion in the patients with glioma, who had received only irradiation treatment, and in the youngest of the patients with craniopharyngioma. Of the 10 young adults tested none showed a good response. It is concluded that GH-RH is useful in differentiating between GH deficiency of hypothalamic origin and that of pituitary origin, and in selecting those patients who might benefit from long-term treatment with GH-RH in the future.     

Greater efficiency of human growth hormone therapy in children below five years of age with growth hormone deficiency. A 5-year follow-up study

The effect of human growth hormone (hGH) therapy was studied in 39 prepubertal children with growth hormone deficiency (24 with isolated growth hormone deficiency; 15 with multiple pituitary hormone deficiencies) who had been treated for 2-5 years. They were divided into two groups according to age at the initiation of therapy: group A (n = 21), 0.7-4.8 years (mean chronological age, 2.9 +/- 1.4 years, and bone age, 1.2 +/- 0.9 years); group B (n = 18), 5.2-9.9 years (mean chronological age, 7.4 +/- 1.3 years, and bone age, 4.0 +/- 1.5 years). hGH was given at an initial dose of 2-4 IU 3 times/week, raised to 4-6 IU 3 times/week when growth velocity slowed. In the first year, the mean height SDS gain was 1.7 for group A and 0.8 for group B, and in the second year, 1.1 and 0.1, respectively. Subsequently this remained consistent. Bone age advancement was significantly slower in the younger group (3.8 vs. 5.8 years during 5 years) although this group had a greater catch-up response to therapy. It is concluded that hGH therapy is significantly more effective in achieving normalization of height when treatment is initiated at an early age.     

Echocardiographic assessment of subclinical left ventricular eccentric hypertrophy in adult-onset GHD patients by geometric remodeling: an observational case-control study

Background

Most patients with growth hormone deficiency (GHD) show high body mass index. Overweight subjects, but GHD patients, were demonstrated to have high left ventricular mass index (LVMi) and abnormal LV geometric remodeling. We sought to study these characteristics in a group of GHD patients, in an attempt to establish the BMI-independent role of GHD.

Methods

Fifty-four patients, 28 F and 26 M, aged 45.9 ± 13.1, with adult-onset GHD (pituitary adenomas 48.2%, empty sella 27.8%, pituitary inflammation 5.5%, cranio-pharyngioma 3.7%, not identified pathogenesis 14.8%) were enrolled. To minimize any possible interferences of BMI on the aim of this study, the control group included 20 age- and weight-matched healthy subjects. The LV geometry was identified by the relationship between LVMi (cut-off 125 g/m²) and relative wall thickness (cut-off 0.45) at echocardiography.

Results

There was no significant between-group difference in resting cardiac morphology and function, nor when considering age-related discrepancy. The majority of patients had normal-low LVM/LVMi, but about one fourth of them showed higher values. These findings correlated to relatively high circulating IGF-1 and systolic blood pressure at rest. The main LV geometric pattern was eccentric hypertrophy in 22% of GHD population (26% of with severe GHD) and in 15% of controls (p = NS).

Conclusion

Though the lack of significant differences in resting LV morphology and function, about 25% of GHD patients showed high LVMi (consisting of eccentric hypertrophy), not dissimilarly to overweight controls. This finding, which prognostic role is well known in obese and hypertensive patients, is worthy to be investigated in GHD patients through wider controlled trials.     

Changes of thyroid function during long-term hGH therapy in GHD children. A possible relationship with catch-up growth?

BACKGROUND: Growth hormone (GH) treatment in patients with GH deficiency (GHD) can determine changes in the thyroid function. The clinical significance of these changes remains controversial, and all studies have so far covered rather a short period--usually no longer than one year. OBJECTIVE: To determine the effect of long-term recombinant hGH treatment in children with idiopathic GHD on the thyroid function. PATIENTS AND METHODS: Nineteen prepubertal children (12 boys and 7 girls, mean age 9.2 +/- 3.1 years) with idiopathic GHD were studied and followed for twenty-four months. None of the patients showed multiple pituitary hormone deficiencies. Nineteen healthy children matched for age and sex acted as controls. RESULTS: Patients with GHD showed a significant increase in TT (3) at twelve months and in FT (3) at six and twelve months after starting GH treatment, with a significant decrease at eighteen and twenty-four months. TT (4) level decreased significantly at twelve months and increased significantly at eighteen and twenty-four months. FT (4) also decreased, but only slightly, after twelve months of hGH treatment, and then increased significantly at twenty-four months. TSH levels did not vary significantly during the course of therapy. TT (3)/TT (4) and FT (3)/FT (4) ratios increased significantly after six and twelve months of therapy and significantly decreased later, approaching pre-therapy values. The SDS of Growth Velocity (SDS-GV) increased remarkably during the first year of therapy and then decreased significantly during the second year, although it remained significantly higher than the pre-therapy values. TT (3) and TT (3)/TT (4) ratio displayed a significant correlation with SDS-GV at twelve months of therapy. In a multiple regression analysis with age, bone age, parental height, GH dose, TT (3,) TT (3)/TT (4), and the SDS of IGF-I, only the TT (3)/TT (4) ratio at twelve months of therapy (p < 0.001) was identified as a significant predictor of SDS-GV. CONCLUSION: Our data confirm that changes in thyroid function are present in GHD children during long-term hGH therapy. These changes probably resulted from the effect of hGH on the peripheral metabolism of thyroid hormones and appear to be transitory, disappearing during the second year of hGH treatment. We speculate on the functional significance of these changes, and in particular, on their role in catch-up growth after hGH therapy.     

Auxological and endocrine evolution of 28 children with Prader-Willi syndrome: effect of GH therapy in 14 children

We report on the auxological and endocrine evolution of 28 patients presenting with Prader-Willi syndrome. Half of them received growth hormone (GH) therapy (group 2). The spontaneous auxological evolution was analyzed in the two groups from 2 to 8 years; the mean SDS for height remained stable (-0.6 +/- 0.6) in group 1 and decreased (from -2.0 +/- 0.9 to -2.7 +/- 0.6) in group 2. Magnetic resonance imaging showed marked pituitary hypoplasia in the two groups. In group 2, the mean GH peak after two provocative tests was 3.8 +/- 2.4 microg/l, the mean SDS values for insulin-like growth factor I levels were -2.0 +/- 1.5 (range from -0.5 to -5.0). The mean duration of GH treatment was 3.6 +/- 2.9 (range 1-9.3) years. 14 children completed 1 year of treatment. The two groups had opposite evolutions in Delta SDS for height (-0.8 +/- 0.8 vs. +1.1 +/- 0.8), for growth velocity (-1.9 +/- 2.2 vs. +2.9 +/- 2.7), and for Z score of the body mass index (+0.37 +/- 1.3 vs. -0.14 +/- 0.76; group 1 vs. group 2). This retrospective study shows that, in children with Prader-Willi syndrome and true GH deficiency, long-term GH therapy is effective in increasing growth velocity and in maintaining body mass index.     

Bone age progression during the first year of growth hormone therapy in pre-pubertal children with idiopathic growth hormone deficiency, Turner syndrome or idiopathic short stature, and in short children born small for gestational age: analysis of data from KIGS (Pfizer International Growth Database)

BACKGROUND/AIMS: The beneficial effects of growth hormone (GH) therapy on statural growth in children are well established, but the effects on skeletal maturation are less clear. The progression of bone age (BA) was therefore studied during the first year of GH treatment in pre-pubertal children with idiopathic GH deficiency (GHD), Turner syndrome (TS) or idiopathic short stature (ISS), and in short pre-pubertal children born small for gestational age (SGA). METHODS: Cross-sectional data on 2,209 short children with idiopathic GHD, 694 with TS, 569 with ISS and 153 with SGA were analysed. Longitudinal data were also analysed from 308 children with idiopathic GHD, 99 with TS, 57 with ISS and 29 with SGA. All patients included in the study were enrolled in KIGS (Pfizer International Growth Database) and were being treated with recombinant human GH (Genotropin). BA was assessed using the Greulich and Pyle method at baseline and after 1 year of GH therapy. RESULTS: In all groups of patients the mean progression of BA was 1 year during the year of GH therapy, although there was considerable individual variation. Progression of BA was not correlated with chronological age, BA, height SD score (SDS) or body mass index SDS at the onset of GH therapy. There was also no consistent effect of the GH dose on BA progression. CONCLUSION: Progression of BA appears to be normal in patients receiving GH in these diagnostic groups, at least over the first year of treatment in pre-puberty.     

Differential effects of hGH and IGF-I on body proportions

The differential growth effects of hGH and IGF-I on the upper/lower (U/L) body segment in relation to height (Ht) were analyzed in 15 patients with isolated Growth hormone deficiency (IGHD,:7M, 8F) mean age 5.0 +/- 3.2 (SD) years treated with hGH; 21 patients with multiple pituitary hormone deficiency including growth hormone (MPHD: 14M, 7F) aged 10.0 +/- 3.8, treated with hGH; 9 patients with Laron Syndrome (LS) (4M,5F) aged 6.9 +/- 5.6 years treated with IGF-I; 9 boys with intrauterine growth retardation (IUGR) aged 6.3 +/- 1.25 years treated by hGH; and 22 boys with idiopathic short stature (ISS) aged 8.0 +/- 1.55 years treated by hGH. The dose of hGH was 33 microg/kg/day, that of IGF-I 180-200 microg/kg/day. RESULTS: the U/L body segment ratio in IGHD patients decreased from 2.3 +/- 0.7 to 1.1 +/- 0.7 (p <0.001), and the Ht SDS increased from -4.9 +/- 1.3 to 2.3 +/- 1 (p < 0.001) following treatment. In MPHD patients the U/L body segment decreased from 1.1 +/- 1.1 to -0.6 +/- 1.0 (p < 0.001), and the Ht SDS increased from -3.3 +/- 1.4 to -2.5 +/- 1.0 (p < 0.009). In the LS group the U/L body segment ratio did not change with IGF-I treatment but Ht improved from -6.1 +/- 1.3 to -4.6 +/- 1.2 (p < 0.001), The differential growth response of the children with IUGR and with ISS resembled that of the children with LS. CONCLUSIONS: hGH and IGF-I act differentially on the spine and limbs.     

Fracture rates in patients with growth hormone deficiency

There is some evidence that bone mass is reduced in the majority of adult patients with growth hormone deficiency (GHD), suggesting that such patients have an increased risk of fractures and clinically significant osteoporosis. To date, there have been only two reports of fracture rates in patients with hypopituitarism. Both these retrospective studies show an increased fracture prevalence in this patient group compared with the general population, but patient numbers were low for assessing fracture rates. However, an analysis of data from a large-scale pharmacoepidemiological survey of adults with GHD, KIMS (Pharmacia International Metabolic Database), confirms the findings of these earlier studies. The prevalence of all fractures among patients in KIMS was 2.7 times that in the control population, and the risk of fracture was independent of whether patients had isolated GHD or multiple pituitary hormone deficiencies. The results suggest that GHD is a risk factor for fractures, if a direct endocrine cause is assumed. Notably, there are some data on subgroup analyses from KIMS suggesting that growth hormone replacement therapy may help to reduce fracture risk, although further evidence is needed to confirm this effect.     

Defining growth hormone status in adults with hypopituitarism

The identification of adults with severe growth hormone (GH) deficiency (GHD) is not straightforward. The insulin tolerance test remains the gold standard diagnostic test, although other stimuli such as GH-releasing hormone-arginine are gaining acceptance. Insulin-like growth factor-I has a poor diagnostic sensitivity in adult-onset GHD, but is more useful in the subgroup of adults with childhood-onset GHD. Therapeutic developments include increasing recognition of the need to continue GH therapy beyond final height in young adults with severe GHD on retesting. Consensus guidelines have provided a useful algorithm to identify individuals requiring retesting and the number of tests needed. The concept of partial GHD, recognized by paediatric endocrinologists for many years, is being examined in adults with hypothalamic-pituitary disease. Preliminary evidence suggests that this entity is associated with metabolic and anthropometric abnormalities intermediate between those in severe GHD and in healthy controls. It remains to be seen whether this subgroup will derive benefit from GH therapy. To date, therapeutic benefits of GH have been demonstrated only in adults with severe GHD. It is, therefore, imperative that these individuals are unequivocally identified; the diagnosis becomes more uncertain in the presence of obesity, increasing age, and in the absence of additional pituitary hormone deficits.