Federico Baronio

Thyroid nodules and cancer in children and adolescents affected by autoimmune thyroiditis

OBJECTIVE To investigate the association between juvenile autoimmune thyroiditis (JAT) and thyroid cancer in pediatric patients. DESIGN We conducted a retrospective study among children and adolescents affected by JAT. SETTINGS Data from 6 Italian pediatric endocrinology centers were collected. PARTICIPANTS Three hundred sixty-five children and adolescents affected by JAT diagnosed at 3.6 to 17.0 years of age. INTERVENTIONS All patients underwent clinical examination and thyroid function test every 6 to 12 months and thyroid echography every 12 to 24 months. Fine-needle aspiration biopsy was performed in 39 patients with nodule diameter of 1 cm or larger, as well as in 4 patients with nodule diameter of less than 1 cm and echographic findings suspicious for neoplasm. Twenty-three patients underwent surgery. MAIN OUTCOME MEASURES Thyroid function, echographic pattern, nodule diameter, the presence of lymphadenopathy, and cytologic and histologic diagnoses were considered. RESULTS Thyroid nodules were found in 115 patients; findings in 11 of these were consistent with papillary carcinoma, with 5 exhibiting lymph node metastasis. The prevalence of male sex among patients with cancer was greater than that among patients with JAT (odds ratio [OR], 2.95; 95% confidence interval [CI], 1.44-6.20). The growth of nodules during levothyroxine sodium therapy (OR, 15.60; 95% CI, 1.87-181.90) and the finding of lymphadenopathy (OR, 5.44; 95% CI, 1.05-30.50) were statistically significantly associated with the presence of cancer, while uninodularity and hypoechogenicity were not. CONCLUSIONS The observed prevalences of thyroid nodules and thyroid cancer in our JAT case series were 31.5% and 3.0%, respectively. Papillary carcinoma was the only histotype detected. The finding of lymphadenopathy, a lack of response to levothyroxine therapy, and nodule hypoechogenicity suggested malignancy. Fine-needle aspiration biopsy was reliable in selecting patients for referral to surgery.

Height as a Risk Factor for Osteosarcoma

Previous investigations have suggested that osteosarcoma may be associated with a taller stature, but the relationship between height and osteosarcoma remains controversial. Height at diagnosis was evaluated in a continuous series of 962 osteosarcoma subjects treated between 1981 and 2001. Patients diagnosed during growth (group 1) were separated from those diagnosed in adulthood (group 2). Height (H) and final height (FH) were expressed as standard deviation scores (SDS), calculated by national reference data. Group 1 subjects were above the 50th centile and their mean H-SDS values (0.31 ± 1.1) were significantly higher than the mean FH-SDS values (P < 0.0001) of the group 2 subjects, both in males and females. In contrast, the mean FH-SDS (0.01 ± 1.1) of group 2 did not differ from that of the reference population. The highest incidence of osteosarcoma was at 12.5 years in females, 14.5 years in males. These data confirm previous observations of an association between osteosarcoma development and height, at least in growing individuals. The higher incidence during the pubertal spurt, in the anatomic sites of greater growth and in taller individuals, suggests that growth factors play an important role in the pathogenesis of this bone cancer.

Comparison between liquid and tablet formulations of levothyroxine in the initial treatment of congenital hypothyroidism.

OBJECTIVE To evaluate the effects of liquid (drops) and tablet formulations of levothyroxine in homogeneous groups of infants with congenital hypothyroidism (CH) as diagnosed through neonatal screening. STUDY DESIGN Forty-two consecutive infants with CH were subdivided into 2 groups consisting of infants with the severe or the moderate/mild form. For each form, the infants with CH were randomly assigned to receive liquid (group 1) or tablet (group 2) formulation. In all patients, thyroid function tests were performed before the beginning of therapy and at 15 and 30 days and at 3 and 6 months after the beginning of therapy. RESULTS In the severe form, after 15 days of treatment, serum thyrotropin (TSH) levels became normal in 8 of 9 patients in group 1 and in 5 of 9 patients in group 2; serum free triiodothyronine (fT3) levels were significantly higher in group 1 than in group 2; and serum fT4 levels were higher than the upper limit of the normal range in all patients in both groups. During the follow-up, there were significantly more patients with suppressed TSH concentrations in group 1 than in group 2. In the moderate/mild form, the patients of group 1 and group 2 showed median values of TSH, fT3, and fT4 that were not significantly different. No clinical or electrocardiographic signs of heart disease were found. There were no significant differences in the developmental quotient between group 1 and group 2 patients with severe and moderate/mild CH. CONCLUSIONS Our data seem to indicate that there is not complete bioequivalence between drops and tablets, especially in infants with severe CH.

Long-term Clinical Significance of Thyroid Autoimmunity in Children with Celiac Disease

OBJECTIVE To evaluate the long-term outcome of thyroid function and autoimmunity in a large series of children with celiac disease. STUDY DESIGN This longitudinal, retrospective study (duration of follow-up, 8.9 +/- 4.0 years) was conducted at the Pediatric Department, University of Bologna, Italy. One hundred thirty-five consecutive patients diagnosed between June 1990 and December 2004 and followed on a gluten-free diet were examined. Inclusion criteria were good dietary compliance and duration of follow-up for at least 3 years. RESULTS Of 101 patients who never showed positive antithyroid titers during the follow-up, 86 remained euthyroid; 15 showed high thyroid-stimulating hormone values at diagnosis that normalized in 11 cases after 12 to 18 months of gluten withdrawal. Of 31 patients with persistently positive antibody titers, 23 (74%) remained consistently euthyroid during the follow-up and 8 (26%) had a subclinical hypothyroidism. The prevalence of cases with positive antibodies was similar in children with growth retardation or gastroenterological symptoms at diagnosis and different durations of gluten exposure. CONCLUSIONS The presence of antithyroid antibodies in children with celiac disease has a low predictive value for the development of thyroid hypofunction during the indicated surveillance period. Longer follow-up is needed.

Birth length and weight in congenital adrenal hyperplasia according to the different phenotypes

The aims of this study were to: (1) retrospectively investigate the birth length and weight of our patients with congenital adrenal hyperplasia (CAH); (2) compare these parameters with standards for birth length and weight recently assessed in an Italian control population; (3) evaluate whether neonatal auxological data may change depending on the different clinical forms of CAH. Birth length and weight were retrospectively evaluated in 101 children with different clinical forms of CAH and compared with standards for birth length and weight assessed in an Italian control population. In both sexes the average birth length of patients with classical CAH was greater than the mean birth length of the controls, and both length and weight were greater in children with classical CAH than in those with the non-classical form. Among the patients with classical CAH, those with the salt-wasting form were longer but also weighed less than those with the simple-virilizing form. Conclusions: (1) fetal length velocity in patients with CAH may be increased only in those infants with classical forms of the syndrome, while it is unaffected in those with the non-classical form; (2) the greater the enzymatic activity impairment, the longer the birth length of newborns with CAH.

Focal nodular hyperplasia of the liver after intensive treatment for pediatric cancer: is hematopoietic stem cell transplantation a risk factor?

Focal nodular hyperplasia (FNH) is a benign hepatic lesion very rarely described in the pediatric population. It has been reported more frequently in patients treated for pediatric cancers with chemotherapy or hematopoietic stem cell transplantation. The use of high dosage of alkylating agents, the occurrence of venous occlusive disease, graft-versus-host disease, and other variables linked to the hematopoietic stem cell transplantation procedure can represent risk factors for the development of FNH in the pediatric age. The discovery of hepatic nodules in the follow-up of patients treated for malignancies suggests recurrence of disease and raises a diagnostic dilemma. Here we describe possible risk factors, clinical and radiological findings of eight pediatric patients who developed focal nodular hyperplasia after hematopoietic stem cell transplantation. The aim of this report is to provide useful diagnostic tools to facilitate accurate diagnosis of FNH and suggest a correct management of this benign lesion during postcancer follow-up.

A new DAX1 gene mutation associated with congenital adrenal hypoplasia and hypogonadotropic hypogonadism

We report on a DAX1 gene investigation in a patient with X‐linked adrenal hypoplasia congenita (AHC) and hypogonadotropic hypogonadism (HH) in order to identify mutations causing this disorder and to confirm the clinical diagnosis. The description of the clinical course of the condition with a detailed documentation of longitudinal data is also reported. A male newborn was referred at 45 days of life because of vomiting, dehydration, and weight loss. The diagnosis was primary adrenal insufficiency. The appropriateness of glucocorticoid therapy during the prepubertal period was difficult to judge because of elevated ACTH levels on one hand and progressive retardation of bone age on the other hand. Basal and GnRH stimulated gonadotropin levels remained low during the entire period of examination and exogenous gonadotropin treatment was begun. This had to be interrupted at age 14.6 years because of the occurrence of a 3rd degree anaplastic ependimoma of the left posterior‐parietal region, without apparent lepto‐meningeal involvement. The molecular analysis of DAX1 gene of the propositus showed deletion of nucleotides AAT in exon 2, resulting in the loss of the Asn430. No alterations were found in the mother and grandmother. This deleted residue lies in one of the helices forming the hydrophobic core of the ligand‐binding domain (LBD); thus this mutation may be the cause of the observed phenotype. Further investigations are needed to verify its causal role in AHC associated with HH.

Severe hypoglycemic episodes: A persistent threat for children with Type 1 diabetes mellitus and their families

Background: As lowering glycated hemoglobin (HbA1c) levels is still the main goal of insulin treatment, severe hypoglycemia (SH) remains a common experience in children with Type 1 diabetes mellitus (T1 DM) and their families. Aim: This study aims to evaluate the incidence and the clinical features of SH episodes in our Centre in the last 20 yr. Subjects and Methods: We analyzed SH incidence in 269 patients (pts) diagnosed from 1990 to 2010 (total follow-up 2212.9 pts/yr). Inclusion criteria were at least 3 visits/yr and 1-yr follow-up. SH episode was defined as any condition of low blood glucose requiring third-party assistance. Results: 50.2% of patients experienced at least 1 SH episode for a total of 345 episodes. Whole incidence was 15.6/100 pts/yr, slightly different between first and second decade (12.6 vs 16.5, p=0.047). HbA1c at the time of SH was lower in the non-basal bolus group (7.4±1.3 vs 8.2±1.4; p=0.0001) and worsened 3 months later (p=0.0001). Impaired awareness was the main or only symptom in 43.5%. SH occurred at night in 32% of patients; they were significantly younger than those with SH at other times. Five SH episodes or more occurred in 8.1% of patients who presented a lower HbA1c, a younger age and shorter disease duration than the other patients. HbA1c at first SH was negatively correlated with number of SH (r=−0.20; p=0.05). Conclusions: Despite the advent of new insulin regimens, we confirm that SH still represents a relevant risk and a current threat for patients with T1DM and their families.

Clinical relevance of short-chain acyl-CoA dehydrogenase (SCAD) deficiency: Exploring the role of new variants including the first SCAD-disease-causing allele carrying a synonymous mutation

Short-chain acyl-coA dehydrogenase deficiency (SCADD) is an autosomal recessive inborn error of mitochondrial fatty acid oxidation caused by ACADS gene alterations. SCADD is a heterogeneous condition, sometimes considered to be solely a biochemical condition given that it has been associated with variable clinical phenotypes ranging from no symptoms or signs to metabolic decompensation occurring early in life. A reason for this variability is due to SCAD alterations, such as the common p.Gly209Ser, that confer a disease susceptibility state but require a complex multifactorial/polygenic condition to manifest clinically. Our study focuses on 12 SCADD patients carrying 11 new ACADS variants, with the purpose of defining genotype–phenotype correlations based on clinical data, metabolite evaluation, molecular analyses, and in silico functional analyses. Interestingly, we identified a synonymous variant, c.765G > T (p.Gly255Gly) that influences ACADS mRNA splicing accuracy. mRNA characterisation demonstrated that this variant leads to an aberrant splicing product, harbouring a premature stop codon. Molecular analysis and in silico tools are able to characterise ACADS variants, identifying the severe mutations and consequently indicating which patients could benefit from a long term follow- up. We also emphasise that synonymous mutations can be relevant features and potentially associated with SCADD.

The Influence of Growth Hormone Treatment on Glucose Homeostasis in GrowthHormone-Deficient Children: A Six-Year Follow-Up Study

Background: Growth hormone (GH) influences glucose homeostasis by negatively affecting insulin sensitivity, leading to a compensatory increase in insulin secretion. It has recently been reported, in animals and humans, that GH might also stimulate insulin secretion by directly affecting the growth and function of pancreatic β-cells. The aim of this work was to longitudinally study the insulin sensitivity (HOMA-S), insulin secretion [insulinogenic index (IGI)] and capacity of β-cells to adapt to changes in insulin sensitivity [oral disposition index (ODI)] in GH-deficient (GHD) children under GH treatment. Methods: We studied 99 GHD (62 male, 37 female; age 8.9 ± 3.5 years) children for a median period of 6 years (range 1.5-16.2). Every year, our patients underwent an oral glucose tolerance test, which was used to calculate the HOMA-S, IGI and ODI. Results: Although HOMA-S remained unchanged, an increase in IGI and ODI was observed, becoming significant after 6 years of treatment (1.25 ± 1.28 vs. 2.35 ± 2.38, p < 0.05 and 0.57 ± 0.68 vs. 1.50 ± 1.92, p < 0.01, respectively). Conclusion: Our results suggest a positive influence of GH treatment on the β-cell secretory capacity in children with GH deficiency.