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M Cappa

Publications and source records attributed to M Cappa.

At least 19 recordsLinked to original sources

Raised C-reactive protein levels in patients with recent onset type 1 diabetes.

BACKGROUND: To investigate serum concentrations of high-sensitive C-reactive protein (CRP) and alpha(1)-acid glycoprotein (AGP) in patients with T1DM, at diagnosis and after 12 months of intensive insulin therapy (T12). METHODS: CRP and AGP were measured in 44 recent onset T1DM patients (26M/18F, mean age 14.9 +/- 9.1 years), and 44 age- and sex-matched controls, using a highly sensitive immunonephelometric assay. RESULTS: There were no significant differences in the concentrations of high-sensitive C-reactive protein (hs-CRP) and AGP between patients and controls. hs-CRP levels significantly increased in patients at T12 compared to the levels at diagnosis [0.69 (0.14-15.5) versus 0.43 (0.14-7.47) mg/L, p < 0.05; for males: 0.77 (0.14-15.5) versus 0.35 (0.14-7.47) mg/L, p < 0.05; for females the increase was not significant]. AGP levels were not different at T12 compared to diagnosis. No significant correlations were found between hs-CRP and body mass index (BMI), C-peptide, glycosylated haemoglobin, or insulin dose. A strong correlation was found between hs-CRP values at diagnosis and those at T12 (rho = 0.73, p < 0.001); indeed, patients with hs-CRP levels above the 50th percentile at diagnosis showed significantly increased hs-CRP values at T12 compared to patients with baseline hs-CRP levels under the 50th percentile [1.61 (0.18-15.5) versus 0.16 (0.14-1.92) mg/L, p < 0.0001)], and to controls [0.55 (0.14-6.50), p = 0.001]. CONCLUSIONS: This is the first report showing that, despite good metabolic control, 1 year of overt T1DM is sufficient to increase hs-CRP levels, especially in males. hs-CRP levels at diagnosis is a predictor for the values observed at 12 months, suggesting the possibility to select a subgroup of patients requiring strict follow-up for cardiovascular complications.

Adolescent↗

Divergent phenotype of two siblings human leukocyte antigen identical, affected by nonclassical and classical congenital adrenal hyperplasia caused by 21-hydroxylase deficiency.

CONTEXT: Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders most often caused by enzyme 21-hydroxylase deficiency. Most mutations causing enzymatic deficiency are generated by recombinations between the active gene CYP21 and the pseudogene CYP21P. Only 1-2% of affected alleles result from spontaneous mutations. The phenotype of CAH varies greatly, usually classified as classical or nonclassical, depending on variable degree in 21-hydroxylase activity. Here we report a divergent phenotype of two human leukocyte antigen identical siblings, affected by nonclassical and classical CAH caused by 21-hydroxylase deficiency due to different genotype. PATIENTS AND METHODS: Using direct sequencing method and Southern blot, we studied two children (one male and one female), affected, respectively, by nonclassical and classical CAH and their parents. RESULTS: The mother was heterozygous for the Q318X mutation, and the father was heterozygous for the V281L mutation. The brother was a compound heterozygote for the mutations V281L and Q318X, whereas the proband was compound heterozygote for the Q318X mutation and a large conversion. The two children are human leukocyte antigen identical (A*02;B*14;DRB1*01/A*33;B*14;DRB1*03). CONCLUSIONS: Different phenotype of the proband is the result of compound heterozygosity for the maternal mutation Q318X and a de novo large conversion.

Adrenal Hyperplasia, Congenital↗

Clinical effects of early treatment with insulin glargine in patients with cystic fibrosis and impaired glucose tolerance.

Diabetes mellitus is an increasing complication of cystic fibrosis (CF), as a result of the improved life expectancy. There is clear association between diabetes and increased morbidity and mortality. Lung function and clinical status deteriorate up to 2-4 yr before the diagnosis of CF-related diabetes (CFRD). The aim of our study was to evaluate the effects, on glucose homeostasis and clinical status, of the early treatment with insulin glargine in CF patients with impaired glucose tolerance (IGT). We selected six subjects with IGT diagnosed at oral glucose tolerance test (OGTT). Median age was 18.12 yr (range 9.2-27.8). Insulin glargine was administered at the median dosage of 0.3 U/kg/day (range 0.2-0.5). After the initial adjustment of the dosage, no patient manifested hypoglycemia during treatment. Median glycosylated hemoglobin (HbA1c) did not show any significant variation during treatment: it was 5.9% at baseline (range 5.5-6.2) and 6.1% (range 5.0-6.7) at the end of follow-up (p=0.496). Median body mass index (BMI) z-score significantly increased during treatment, from -0.95 (range -3.2-+0.6) at baseline to -0.5. (range -3.0-+0.9) at the end of follow-up (p=0.026). Lung function, measured by median forced expiratory volume in the first second (FEV1%), showed a mild but significant improvement during insulin treatment. It was 72.7% at baseline (range 41.5-98.4) and 76.7% (range 42.0-106.8) at the end of follow-up (p=0.027). No significant variation was found between the number of hospitalizations for clinical exacerbation (no./patient/yr) in the last 2 yr before treatment and during follow-up. Median number at baseline was 1.95/patient/yr (range 1-3) and 2.0/patient/yr (range 1-3) at follow-up (p=0.715). Our data seem to indicate that early insulin therapy can be safe, no patient manifested hypoglycemia or other adverse effects during treatment. Insulin is an anabolic hormone implicated in both lipid and protein metabolism. The appearance of IGT out of infections can indicate an early insulin deficiency, with a potential impact on the nutritional and clinical status of the patient, even before the appearance of overt diabetes. Larger controlled trials are necessary to verify if early insulin therapy is able to reduce the deterioration of nutritional status and lung function associated with the onset of IGT.

Adolescent↗

Metabolic factors affecting residual beta cell function assessed by C-peptide secretion in patients with newly diagnosed type 1 diabetes.

BACKGROUND: In recent onset of type 1 diabetes, the residual beta cell function, assessed by baseline and/or stimulated C-peptide secretion, can be a useful parameter to establish the extension of beta cell destruction. How metabolic parameters at diagnosis influence residual C-peptide secretion is not well established. PATIENTS AND METHODS: We analyzed 553 consecutive patients with recent onset (<4 weeks) of type 1 diabetes (250 females and 303 males, mean age 15+/-8 years). Baseline and stimulated C-peptide by i.v. glucagon were evaluated using a highly sensitive radio-immunoassay. Metabolic parameters including blood glucose, HbA1c, insulin dose, and BMI were also evaluated. RESULTS: Baseline and stimulated C-peptide were 0.26+/-0.22 and 0.47+/-0.38 nmol/l and correlated positively with age (p<0.001). There was no significant correlation between C-peptide and blood glucose at diagnosis. BMI was positively correlated with both baseline and stimulated C-peptide secretion (p<0.001). By contrast, HbA1c levels inversely correlated with both baseline and stimulated C-peptide secretion (p<0.001). CONCLUSION: In type 1 diabetes at diagnosis, baseline and stimulated C-peptide are higher in pubertal and young adult patients compared with pre-pubertal patients suggesting that such parameter can be used as an end point marker for studies aimed at protecting and/or restoring beta cells in patients with substantial beta cell function. High levels of HbA1c and lower BMI are dependent variables of C-peptide values.

Adolescent↗

Influence of gender and pubertal stage at diagnosis on growth outcome in childhood thyrotoxicosis: results of a collaborative study.

OBJECTIVE: To evaluate the influence of sex as well as pubertal stage at diagnosis on the growth outcome of childhood thyrotoxicosis. DESIGN: Retrospective, collaborative study. PATIENTS AND METHODS: Longitudinal auxological evaluation in 101 patients (M/F 23/78) for 4.7 +/- 3.1 years subdivided according to pubertal stage at diagnosis into prepubertal (group I) and pubertal (group II). RESULTS: At diagnosis height and bone age (BA) standard deviation score (SDS) were positive both in girls and boys of groups I and II. In boys of group II, height SDS was significantly higher than in girls of the same group (P = 0.007) and in boys of group I (P = 0.026). During the follow-up, in group I, height SDS remained positive without significant differences between boys and girls, and in group II, height SDS remained significantly lower in girls than in boys. The age at onset of puberty and the age at menarche were within the normal range. Final height (FH) was within target height (TH) range in all groups The FH SDS and the height gain (FH-TH) were similar in girls and in boys in group I and significantly higher in boys than in girls (P < 0.05) in group II. The boys of group II showed a mean height gain significantly greater than that found in all the other groups. CONCLUSIONS: Despite the advancement of BA at presentation, there were no adverse effects on subsequent growth and FH; the growth outcome seems to be better in boys than in girls in group II.

Adolescent↗

XK-aprosencephaly and related entities.

We offer further biological characterization of the XK atelen/aprosencephaly syndrome in two infants, one with prolonged survival, the other presenting prenatally with apparent hydranencephaly and an orbital tumor (OS). Familial occurrence in the former born to presumably nonconsanguineous Lybian parents may represent parental germinal mosaicism or autosomal recessive inheritance. Both had apparently normal chromosomes; however, the Lybian infant had slightly increased induced chromosome breakage suggesting that this rare multiple congenital anomalies syndrome may involve a DNA repair defect. Virtual absence of atelen/aprosencephalic structures may lead to an arthrogryposis-like prenatal movement disorder. The orbital tumor in the Utah infant consisted of dystopic neural tissue compressing a rudimentary globe and was connected by a thin bridge of neural tissue to the small mass of disorganized brain tissue usually found in atelen/aprosencephalic infants and fetuses. No evidence of an encephaloclastic process was found in the autopsied Utah infant.

Abnormalities, Multiple↗

Long-term results of the surgical treatment of craniopharyngioma: the experience at the Policlinico Gemelli, Catholic University, Rome.

BACKGROUND: Craniopharyngioma (CP) is the most common intracranial non-glial tumour observed in pediatric age. Although histologically benign and amenable to surgical treatment, its location and relation with vital nervous and vascular structures makes the feasibility of a radical resection difficult even in the microneurosurgery era. Beside the difficulties experienced when performing tumour resection, post-operative complications, such as endocrinological imbalance, represent another point that makes CP total excision a challenge. In order to avoid such complications, some authors have suggested to renounce to radical resection and to rely on post-operative radiation therapy to minimise the risk of residual tumour progression. METHODS: We report our experience with 52 children and adolescents operated on for CP at the Department of Pediatrics, Section of Pediatric Neurosurgery, Catholic University Medical School, Rome, between January 1985 and December 2002. The study included 14 children <5 years old (five less than 2 years of age), 25 between 6 and 10 years old, and 13 more than 10 years old. The most common presenting signs were related to endocrinological imbalance (35 cases), increased intracranial pressure (32 cases), and to a lesser extent, visual compromise (17 cases). Concerning location, CP was intrasellar in three cases; sellar/suprasellar with prominent prechiasmatic growth in 24 cases; retrochiasmatic/3rd ventricular in 14 cases, and giant (with an extension into the middle and/or posterior cranial fossae) in 11 cases. The tumour was managed by means of a single surgical approach in 47 cases and with a two-stage operation in the remaining five cases. In 11 cases of intrasellar or intra/suprasellar midline location, the first surgical approach was done through the transsphenoidal route (which represented the first step of a staged operation in five instances); in the remaining 41 patients, craniotomy was the first surgical procedure. Radical tumour resection was achieved in 40 cases, subtotal (only small tumour remnants adherent to the carotid arteries, 3rd ventricle floor or visual pathways) in nine, and only partial in the remaining three cases RESULTS: Histology demonstrated the adamantinous variant in all cases. Two surgical deaths were recorded in this series (both following a transsphenoidal approach): one secondary to uncontrollable intra-operative bleeding from the carotid artery, and the other to fulminating bacterial meningoencephalitis. Morbidity included endocrinological disturbances, namely hypopituitarism and diabetes insipidus, in more than 80% of cases, worsening of pre-operative visual deficit in six cases, and transitory neurological deficits in five cases. One late death was recorded 2 years after surgery, secondary to electrolytic imbalance although favoured by a major head trauma with subacute subdural haematoma. Nine recurrences occurred 1-8 years after surgery (three true recurrences, and six re-growths of incompletely resected tumours) that required re-operation. Twelve patients underwent radiotherapy, six after an initially incomplete tumour resection and six following relapse. One patient presented with a malignant thalamic glioma 8 years after radiotherapy. At long-term follow-up, all survivors showed good clinical condition, even though approximately 60% relied on hormone replacement, and some patients presented obesity. Diabetes insipidus has subsided in about 80% of the cases; visual deficits improved or remained stable, whereas post-operative neurological deficits subsided in all but one patient. CONCLUSION: In our experience, radical resection of CP represented the first and almost unique treatment modality. Although not insignificant, post-operative mortality and morbidity do not seem to represent a major contraindication in attempting a radical tumour resection whenever possible. On the other hand, extensive hypothalamic involvement should suggest a less aggressive attitude.

Adolescent↗

Plasma levels of adrenomedullin in patients with adrenoleukodystrophy/adrenomyeloneuropathy.

BACKGROUND/AIMS: Adrenomedullin (AM) is a recently purified hypotensive peptide and its encoding gene has been sequenced from a human pheochromocytoma. High levels of AM have been shown in Addison's disease (AD). X-linked adrenoleukodystrophy/adrenomyeloneuropathy (ALD/AMN) is a peculiar adrenal insufficiency due to an accumulation of very-long chain fatty acid in adrenal cells and it is very often associated with a devastating demyelination of the central nervous system. METHODS: We studied the AM plasma levels of 22 patients with ALD/AMN (18 with hypoadrenalism, ALDa, and 4 with normal adrenal function, ALDb) and compared them with 18 males with classical AD and 16 normal male subjects. All patients with hyposurrenalism were studied before treatment with hydrocortisone. RESULTS: Both patients with ALD/AMN and AD showed increased levels of AM and all of them showed a significant difference from the control group (p < 0.0001). The plasma renin activity was higher in all patient groups than in the control group (p <0.001 ALDa, ALDb and AD vs. control group). The aldosterone levels were higher in ALDa and ALDb groups than AD (ALDa vs. AD p < 0.01; ALDb vs. control group p < 0.05; AD vs. controls p < 0.01). ACTH plasma levels were higher in ALDa and AD than ALDb and the control group (ALDa vs. AD not significant while ALDa and AD vs. control p <0.0001). CONCLUSIONS: Our data indicate that plasma AM levels in ALDa, ALDb and AD are higher than controls. These results were previously described in untreated AD. While classical AD patients show complete adrenal insufficiency (both mineralocorticoid and glucocorticoid defects), ALD/AMN patients show a less compromised glomerular function, indicating that AM is not completely correlated with mineralocorticoid insufficiency, and that the exact mechanism responsible for the increased AM levels in ALD/AMN is still unknown.

Addison Disease↗

Growth hormone treatment in non-growth hormone-deficient short children.

The unlimited availability of GH obtained by recombinant DNA technology has allowed optimization of treatment in GH-deficient (GHD) children. At the same time it has prompted a number of studies in conditions not characterized by GHD such as Turner syndrome, intrauterine growth retardation, chronic renal failure and other chromosomal and genetic abnormalities associated with short stature. Several controlled and uncontrolled studies have now reported the adult height of patients with short stature and normal GH secretion. Critical reviewing of the data shows that some short non-GHD children may benefit from a prolonged treatment with GH. However, further studies are needed in order to be able to identify the subjects for whom treatment is really beneficial.

Adolescent↗

New findings on X-linked Adrenoleukodystrophy: 5alpha-reductase isoform 2 relative gene expression is modified in affected fibroblasts.

X-linked Adrenoleukodystrophy (X-ALD) is a neurodegenerative disease with an endocrinological component since, in addition to the nervous system, the adrenal cortex and the testis are mainly affected, with corresponding clinical signs. 5Alpha-reductase, a key enzyme in steroid hormone metabolism, catalyzes the conversion of testosterone into the potent androgen dihydrotestosterone and other metabolic steps in steroidogenesis. It is present in two isoforms, 5alpha-reductase isoform 1 and 2, that are encoded by different genes. The isoforms are differently expressed in the tissues, where they have distinct physiological relevance. Our study shows that the expression of isoform 2, evaluated by Real-Time PCR, is significantly altered in fibroblasts from patients affected by X-ALD with respect to controls, whereas isoform 1 is not affected. This is the first demonstration of an alteration of 5alpha-reductase isoform 2 gene expression in X-ALD, that may be related to the steroidogenesis impairment and to the specific organ malfunction.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗

Gender-, age-, body composition- and training workload-dependent differences of GH response to a discipline-specific training session in elite athletes: a study on the field.

Ninety-nine Italian elite athletes (61 M, 38 F, mean age +/- SE: 24.1 +/- 0.6 yr, age range: 17-47 yr) of different disciplines volunteered to participate in this investigation. Basal GH concentrations were significantly higher (p<0.0001) in females (6.2 +/- 1.1 ng/ml) vs males (1.9 +/- 0.5 ng/ml). Basal GH values were negatively correlated with age and body mass index (BMI); no significant correlation was found between GH and IGF-I levels. Among female athletes, 8/38 had basal GH values higher than 10 ng/ml [2/8 athletes were taking oral contraceptives (OC)], while among males 6/61 had values higher than 5 ng/ml. In females, training sessions significantly increased (p<0.0001) basal GH concentrations (peak GH: 18.5 +/- 1.9 ng/ml), while in males GH responses were lower than in females (11.8 +/- 1.4 ng/ml, vs F: p<0.005). Six out of 38 female and 6/61 male athletes were considered GH hypo-responders (i.e. negative difference between peak GH and basal GH values), the large majority of them being subjects with elevated basal GH concentrations. In responsive athletes, peak GH values occurred immediately at the end of the training session both in males and in females; GH concentrations rapidly declined during recovery. No significant correlations were found between peak GH and age, body weight and BMI in either gender. GH responses were directly related (p<0.001) to the intensity of the workload during the sessions. In conclusion, the present study demonstrates that: 1) some elite athletes had increased GH concentrations before training, which were however associated with normal IGF-I levels; 2) GH peaks after a discipline-specific training session were significantly higher in females than in males performing the same discipline, gender-related differences disappearing when post-exercise total GH outputs (area under the curve) were compared; 3) peak GH values were directly correlated with training workload; 4) GH concentrations rapidly declined during recovery, values at the end of the post-training GH sampling being generally lower than those found in basal condition.

Adolescent↗

Maintenance of a normal meal-induced decrease in plasma ghrelin levels in children with Prader-Willi syndrome.

Ghrelin is a 28-amino acid peptide recently identified in the stomach as the endogenous ligand for the growth hormone secretagogue receptor (GHS-R1a). Ghrelin is a potent stimulator of GH secretion. It was recently shown that circulating ghrelin levels in humans rise shortly before and fall shortly after every meal, and that ghrelin administration increases voluntary food intake. The hypothesis that ghrelin hypersecretion might contribute to genetic obesity has never been investigated. In this context, Prader-Willi syndrome is the most common form of human syndromic obesity. As ghrelin affects appetite as well as GH secretion and both are abnormal in PWS, it has been surmised that these alterations might be due to ghrelin dysregulation. The aim of the study was to investigate whether ghrelin is suppressed by the meals differently in PWS children than in PWS adults. Overnight circulating fasting ghrelin levels and ghrelin levels 120 min after breakfast were assayed in 7 PWS children (10.2 +/- 1.7 yr), 7 subjects with morbid obesity (10.3 +/- 1.3 yr), and 5 normal controls (8.4 +/- 1.4 yr). Because of the data spread, no statistical difference was observed in fasting ghrelin levels between PWS and control children (p = NS); anyway, fasting ghrelin levels were significantly lower in obese children than in the other groups (p < 0.05 vs. control and PWS children). Ghrelin levels were slightly suppressed by the meal in control subjects (mean fasting ghrelin: 160.2 +/- 82 pg/ml; after the meal, 141.2 +/- 57 pg/ml, p = NS); the meal failed to suppress ghrelin levels in obese children (mean fasting ghrelin: 126.4 +/- 8.5 pg/ml; after the meal, 119.1 +/- 8.3 pg/ml, p = NS). Interestingly, the meal markedly suppressed ghrelin levels in PWS children (mean fasting ghrelin: 229.5 +/- 70.4 pg/ml; after the meal, 155.8 +/- 34.2 pg/ml, p < 0.01). In conclusion, since a lack of decrease in circulating ghrelin induced by the meal was previously reported in PWS adults, the finding of a meal-induced decrease in ghrelin levels in our population of young PWS would imply that the regulation of the ghrelin system involved in the orexigenic effects of the peptide is operative during childhood, although it progressively deteriorates and is absent in adulthood when hyperphagia and obesity progressively worsen.

Adipose Tissue↗

Voiding dysfunction in x-linked adrenoleukodystrophy: symptom score and urodynamic findings.

PURPOSE: Adrenoleukodystrophy is an x-linked genetic disorder characterized by the breakdown of the myelin sheath surrounding nerve cells in the brain and progressive dysfunction of the adrenal gland with 6 possible phenotypes. Lower urinary tract symptoms affect the quality of life of these patients but only sporadic cases have been previously studied by urodynamics. We report to our knowledge the first series in the literature looking at the prevalent pattern. MATERIALS AND METHODS: A total of 14 children and adults 8 to 53 years old (average age 30) with different phenotypes were referred for evaluation. Of the patients 6 had adrenomyeloneuropathy without cerebral involvement (C-) 3 had the adult cerebral form, 3 had the childhood cerebral form, 1 had cerebral involvement (C+) and 1 was asymptomatic. All patients were submitted to a screening protocol, consisting of the self-administered short form questionnaire International Conference on Incontinence Questionnaire-Short Form (ICIQ-SF) and a 3-day voiding diary. Patients were divided in group 1-no urinary symptoms, ICIQ-SF score 0 and no further investigation (3); group 2-frequency/urgency, ICIQ-SF score 1 to 5, uroflowmetry and post-voiding residual urine (4); and group 3-voiding symptoms and incontinence, ICIQ-SF score greater than 5, standard urodynamic examination (7). RESULTS: A neurogenic overactive bladder was the prevalent urodynamic finding (6 of 7 patients), while hypocontractility was found in 1 case. CONCLUSIONS: Vesicosphincteric dysfunction can be explained by spinal and/or cerebral involvement in the different neurological forms of adrenoleukodystrophy. Attempts at treatment with anticholinergics and neuromodulation in 4 of our patients provided temporary benefit with clear subjective amelioration of symptoms and improved quality of life.

Adolescent↗

Lipoprotein (a) in childhood: correlations with family history of cardiovascular disease.

The association between lipoprotein (a) [Lp(a)] and cardiovascular diseases is well known. Lp(a) is an independent risk factor for the development of atherosclerosis. Little information concerning Lp(a) during childhood is available. The aim of the present investigation was to determine the Lp(a) concentration in a cohort of children aged between 4 and 15 yr and to correlate Lp(a) with: a) overweight status; b) body fat distribution; c) family history of vascular diseases in their parents and grandparents. Six hundred and eighty-nine children (350 males, 339 females), were enrolled in the study. BMI as index of being overweight was calculated; the waist-to-hip ratio (WHR) and the waist-to-thigh ratio (WTR) were calculated to obtain two anthropometric indexes for the pattern of body fat distribution. The areas of visceral (VAT) and subcutaneous adipose tissue (SAT) were evaluated by MRI at the L4-L5 level in only 30 overweight subjects. The serum of Lp(a), total cholesterol (TC), HDL-cholesterol, LDL-cholesterol and triglycerides were evaluated in the whole population. Moreover, the same biochemical study was performed in 70 children's parents randomly chosen. A structured questionnaire was administered to the children's parents to investigate the presence of cardiovascular disease (CVD) in family stories. Our data show no Lp(a) serum differences between children according to sex, age and body composition. The strong correlation between the children's and the parents' Lp(a) concentrations and the occurrence of CVD in their grandparents suggests that Lp(a) represents an important independent early risk factor for the development of CVD in adulthood. Measurements of Lp(a) in childhood may help to evaluate this risk in subjects with family history of cardiovascular diseases.

Adolescent↗

Evaluation of growth disorders in the paediatric clinic.

Growth is one of the most important indicators of child's well-being. The growth pattern is the result of the complex interaction between genetic and environment factors. The gold standard for the diagnosis of GH-deficient (GHD) children is not yet defined. In this review we focused on sensitivity and specificity of the commonly used test for GH secretion and neuroimaging evaluation. Initially, accurate determinations of height, weight, head circumferences and growth velocity should be performed and plotted on an appropriate growth chart. Once chronic non-endocrine diseases such as celiac disease, chronic inflammatory bowel diseases, liver disorders and renal failure have been excluded, children whose height is lower than the 2nd percentile or 2 SD below the mean associated with a decreased height velocity (less than 25th percentile), or height less than -2.4 SD alone, or height velocity less than 10th percentile alone, should be investigated for possible abnormalities in the GH-IGF-I axis. A single IGF-I determination will be the great diagnostic value in all patients with severe GHD or GH insensitivity. Stimulation tests and imaging studies will confirm the etiology. One of the major problems of the provocative tests lies in their poor reproducibility and in the great number of falsely abnormal responses observed also in normal children. Genetic tests are also indicated in all cases of genetic forms. Patients with growth failure and abnormal MRI findings have a very high probability of having GHD and can be identified easily by serum IGF-I or by GH testing. All patients with subnormal GH responses to pharmacological stimulation either with normal or low IGF-I concentration but normal MRI findings should be followed up before a diagnosis of GHD is firmly established.

Adolescent↗