Filippo De Luca

Bone demineralization in cystic fibrosis : Evidence of imbalance between bone formation and degradation

Bone turnover, collagen metabolism, and bone mineral status were investigated in 59 patients with cystic fibrosis and in 72 sex- and age-matched control subjects. In all patients and control subjects serum concentrations of osteocalcin (OC), carboxy-terminal propeptide of type I procollagen (PICP), amino-terminal propeptide of type III procollagen(PIIINP), and cross-linked carboxy-terminal telopeptide of type I collagen(ICTP), and urinary values of cross-linked N-telopeptides of type I collagen (NTX), as well as total body bone mineral content (TBBM) were measured. Higher ICTP (μg/L) and NTX (bone collagen equivalent/urinary creatinine (nmol/mmol) values were found in prepubertal, pubertal, and young adult patients than in control subjects (ICTP: 15.4 ± 2.1 and 13.2± 1.8, p < 0.001; 23.3 ± 5.3 and 20.1 ± 4.1,p < 0.02; 4.8 ± 1.1 and 4.0 ± 1.0, p < 0.05, respectively; NTX: 1047.5 ± 528.6 and 227.8 ± 71.8,p < 0.01; 997.8 ± 391.7 and 376.3 ± 91.0,p < 0.01; 993.2 ± 398.0 and 73.9 ± 28.5,p < 0.01, respectively). Lower OC and PICP levels (μg/L) were showed in pubertal patients in comparison with control subjects (OC: 20.2± 12.3 and 39.0 ± 15.1, p < 0.01; PICP: 305.8± 130.4 and 436.2 ± 110.1, p < 0.02, respectively). Lower OC and higher PIIINP levels (μg/L) were found in young adult patients than in control subjects (OC: 4.4 ± 3.0 and 7.0 ± 3.1,p < 0.05; PIIINP: 4.8 ± 1.1 and 3.1 ± 1.0,p < 0.001, respectively). TBBM (z score) was reduced in prepubertal, pubertal, and young adult patients (-0.8 ± 0.4, -1.0± 0.4, -1.1 ± 0.5, respectively). Patients with cystic fibrosis have bone demineralization and imbalance between bone formation and degradation.

Pulmonary autoimmunity as a feature of autoimmune polyendocrine syndrome type 1 and identification of KCNRG as a bronchial autoantigen

Patients with autoimmune polyendocrine syndrome type 1 (APS-1) suffer from multiple organ-specific autoimmunity with autoantibodies against target tissue-specific autoantigens. Endocrine and nonendocrine organs such as skin, hair follicles, and liver are targeted by the immune system. Despite sporadic observations of pulmonary symptoms among APS-1 patients, an autoimmune mechanism for pulmonary involvement has not been elucidated. We report here on a subset of APS-1 patients with respiratory symptoms. Eight patients with pulmonary involvement were identified. Severe airway obstruction was found in 4 patients, leading to death in 2. Immunoscreening of a cDNA library using serum samples from a patient with APS-1 and obstructive respiratory symptoms identified a putative potassium channel regulator (KCNRG) as a pulmonary autoantigen. Reactivity to recombinant KCNRG was assessed in 110 APS-1 patients by using immunoprecipitation. Autoantibodies to KCNRG were present in 7 of the 8 patients with respiratory symptoms, but in only 1 of 102 APS-1 patients without respiratory symptoms. Expression of KCNRG messenger RNA and protein was found to be predominantly restricted to the epithelial cells of terminal bronchioles. Autoantibodies to KCNRG, a protein mainly expressed in bronchial epithelium, are strongly associated with pulmonary involvement in APS-1. These findings may facilitate the recognition, diagnosis, characterization, and understanding of the pulmonary manifestations of APS-1.

Evaluation of the autoimmune regulator (AIRE) gene mutations in a cohort of Italian patients with autoimmune‐polyendocrinopathy‐candidiasis‐ectodermal‐dystrophy (APECED) and in their relatives

Objective   Autoimmune‐polyendocrinopathy‐candidiasis‐ectodermal‐dystrophy (APECED) is a rare syndrome characterized by chronic candidiasis, chronic hypoparathyroidism and Addisons disease. APECED has been associated with mutations in autoimmune regulator (AIRE) gene. Our aim is to perform a genetic analysis of the AIRE gene in Italian APECED patients and in their relatives.

Factors affecting diabetes mellitus onset in cystic fibrosis: evidence from a 10-year follow-up study.

This study reports the results of genotype characterization and of a 10‐y prospective evaluation of clinical status, glucose tolerance and insulin secretion in 28 originally normoglycaemic patients with cystic fibrosis (CF). The aim of the study was to assess whether any genetic, clinical or metabolic parameters could identify in advance those patients at risk of developing diabetes mellitus over time. During the follow‐up 42.8% of patients became diabetic. Neither gender, age nor clinical parameters were significantly different at entry in the patients who eventually developed diabetes compared with those who did not. Insulin secretion during oral glucose tolerance tests (OGTT) deteriorated over time in both groups, whereas a progressive deterioration of glucose tolerance was only evident in the patients who developed diabetes and increased baseline glucose areas were the only predictive parameter of diabetes onset. Genotype analysis revealed significant differences between patients with and without diabetes: ΔF508 homozygosis was more frequent in the first group and N1303K mutation in the second group. In conclusion, in CF: (i) increased glucose areas during OGTT and deterioration of glucose tolerance over time can predict the evolution towards diabetes; and (ii) ΔF508 homozygosis may predispose to the risk of diabetes, whilst N1303K mutation seems to play a protective role.

Linear growth and intellectual outcome in children with long-term idiopathic subclinical hypothyroidism

OBJECTIVE The treatment of children with subclinical hypothyroidism (SH) is controversial for TSH values between 4.5 and 10 mU/l. The aim of this cross-sectional, controlled study was to evaluate growth and intellectual outcome in children with persistent SH who have never been treated with levothyroxine. DESIGN AND METHODS Clinical and auxological parameters, thyroid function, and intellectual outcome were evaluated in 36 children with persistent SH at the age of 9.7±0.6 (range 4-18.0) years. Children had been followed longitudinally for 3.3±0.3 (range 2.0-9.3) years, from first diagnosis of SH until enrollment in the study. Thirty-six age- and sex-matched children were enrolled in the study as controls. RESULTS At study entry, height (-0.8±0.2 SDS), bone age/chronological age (BA/CA ratio 0.92±0.6), and body mass index (BMI -0.1±0.2 SDS) in SH children were normal. Despite long-term duration of SH, none of these parameters showed a worsening with respect to height (-0.7±0.2 SDS), BA/CA (0.97±0.03), and BMI (-0.1±0.2) at the time of first SH detection. None of the children showed overt signs or symptoms of hypothyroidism during the follow-up. Verbal (99.1±2.2), performance (100.4±1.9), and full-scale (99.7±1.9) intelligence quotient (IQ) scores in SH children were normal and comparable to those of controls. No relationship was detected between IQ scores and the degree or duration of SH. CONCLUSIONS Persistent SH in children is not associated with alterations in growth, bone maturation, BMI, and cognitive function or other complaints that could be ascribed to SH even after several years without therapeutic intervention.

Prevalence of overweight and obesity in 2- to 6-year-old Italian children

Objective: To assess the prevalence of overweight and obesity in 2‐ to 6‐year‐old Italian children and to compare the prevalence between the north and the south of the country.

Comparative Evaluation of Therapy with L -Thyroxine versus No Treatment in Children with Idiopathic and Mild Subclinical Hypothyroidism

Background: The question of whether children with subclinical hypothyroidism (SH) should be treated or not is controversial due to the lack of studies on outcomes of SH children treated with L-thyroxine (L-T4) versus those receiving no therapy. Objectives: (a) To evaluate thyroid tests under L-T4 and after therapy withdrawal in 69 SH children (group A) and (b) to compare our results with those recorded in 92 untreated children (group B). Design: Group A children were treated for 24 months and TSH and FT4 levels 3 months after therapy withdrawal were compared with those measured in group B at the end of follow-up in order to investigate treatment effects. Results: The prevalence of children who had normalized TSH at the end of follow-up was higher in group A, but the prevalence of those who had normalized or maintained unchanged TSH was similar in the two groups, as was the prevalence of children who exhibited a TSH increase >10 mU/l. In group A, TSH values at 27 months were associated with baseline values. Conclusions: (a) Two-year treatment in SH children is unable to modify posttherapy outcome of hyperthyrotropinemia; (b) therapy is unable to prevent the risk of further TSH increase after treatment withdrawal, and (c) posttherapy TSH outcome is conditioned by baseline TSH.

BPIFB1 IS A LUNG-SPECIFIC AUTOANTIGEN ASSOCIATED WITH INTERSTITIAL LUNG DISEASE

Autoimmunity targeting the lung-specific antigen BPIFB1 may be important to the pathogenesis of interstitial lung disease. Seeing the Forest by Examining the Trees Sometimes looking at something too closely obscures the big picture. However, when the big picture is too big, a reductionist approach may be best. Interstitial lung disease (ILD) is a complex and heterogeneous disorder, frequently associated with autoimmune syndromes. However, due in part to this heterogeneity, it remains unclear whether autoimmunity directly contributes to ILD. Now, Shum et al. attack this question by example—connecting one form of autoimmune disease, autoimmune polyglandular syndrome type 1 (APS1), with clinical ILD. The authors screened patients with APS1 and found autoantibodies to a lung-specific protein—BPIFB1—associated with the development of ILD in APS1 patients. They then extended these findings to non-APS1–associated ILD and found that 12 to 15% of patients also had these autoantibodies. The authors then examined a potential pathogenic mechanism of these autoantibodies in a mouse model of APS1, finding that similar autoantibodies and development of ILD resulted from a defect in thymic tolerance. Indeed, autoimmune targeting of BPIFB1 could cause ILD in mice without the autoimmune defect. These results suggest not only that ILD may be an autoimmune disorder in APS1 patients but also that autoimmunity may also contribute to pathology in a broader swath of ILD patients. Interstitial lung disease (ILD) is a complex and heterogeneous disorder that is often associated with autoimmune syndromes. Despite the connection between ILD and autoimmunity, it remains unclear whether ILD can develop from an autoimmune response that specifically targets the lung parenchyma. We examined a severe form of autoimmune disease, autoimmune polyglandular syndrome type 1 (APS1), and established a strong link between an autoimmune response to the lung-specific protein BPIFB1 (bactericidal/permeability-increasing fold-containing B1) and clinical ILD. Screening of a large cohort of APS1 patients revealed autoantibodies to BPIFB1 in 9.6% of APS1 subjects overall and in 100% of APS1 subjects with ILD. Further investigation of ILD outside the APS1 disorder revealed BPIFB1 autoantibodies present in 14.6% of patients with connective tissue disease–associated ILD and in 12.0% of patients with idiopathic ILD. The animal model for APS1, Aire−/− mice, harbors autoantibodies to a similar lung antigen (BPIFB9); these autoantibodies are a marker for ILD. We found that a defect in thymic tolerance was responsible for the production of BPIFB9 autoantibodies and the development of ILD. We also found that immunoreactivity targeting BPIFB1 independent of a defect in Aire also led to ILD, consistent with our discovery of BPIFB1 autoantibodies in non-APS1 patients. Overall, our results demonstrate that autoimmunity targeting the lung-specific antigen BPIFB1 may contribute to the pathogenesis of ILD in patients with APS1 and in subsets of patients with non-APS1 ILD, demonstrating the role of lung-specific autoimmunity in the genesis of ILD.

Late hormonal function after testicular torsion

INTRODUCTION Testicular torsion may be an important cause of male infertility. We aimed to investigate the late hormonal function in patients with testicular ischemia/reperfusion injury of the testis after orchidectomy or detorsion. METHODS Twenty patients (mean age, 13.6 years) were prospectively evaluated at a mean of 5 years after testicular torsion. The serum follicle-stimulating hormone, luteinizing hormone (before and after gonadotropin-releasing hormone stimulation), testosterone, and inhibin B were measured. Fifteen age-matched adolescents without evidence of endocrine disease were used as controls for inhibin B values. Data are quoted as mean +/- SEM. RESULTS Twelve patients were treated with detorsion and orchidopexy, and 8 underwent orchidectomy. Serum follicle-stimulating hormone, luteinizing hormone, and testosterone were all within the reference range. Inhibin B levels were significantly reduced in the 2 groups compared with the controls (34.5 +/- 5.2 vs 63.9 +/- 12.8 pg/mL, P = .02), but were not significantly different between the orchidectomy group and the group that underwent detorsion (41.3 +/- 9.7 vs 30.4 +/- 5.9 pg/mL, P = .41). CONCLUSION Hormonal testicular function can be compromised after testicular torsion, although the type of surgery (orchidectomy or orchidopexy) does not seem to change the effect of this ischemia/reperfusion injury.

Thyroid Function Patterns at Hashimoto’s Thyroiditis Presentation in Childhood and Adolescence Are Mainly Conditioned by Patients’ Age

Background: There are few studies investigating the factors which may affect different biochemical presentations of Hashimoto’s thyroiditis (HT) and these are frequently based on limited pediatric populations. Aims: (1) To assess the frequency of thyroid function patterns at HT diagnosis in 608 children and adolescents, and (2) to analyze the factors that affect thyroid status at diagnosis. Results: At presentation, test results showed euthyroidism in 52.1% of patients (subgroup A), overt or subclinical hypothyroidism in 41.4%, and overt or subclinical hyperthyroidism in 6.5%. The mean age of patients with thyroid dysfunctions (subgroup B) was significantly lower than that of subgroup A, and the rate of children below 10 years of age was significantly greater in subgroup B. Other variables related to thyroid function patterns were prepubertal status; association with either Down or Turner syndromes, which correlated with increased risk of thyroid dysfunctions, and association with other autoimmune diseases, which correlated with decreased risk of thyroid dysfunctions. None of the remaining factors analyzed were associated with increased risk of thyroid dysfunctions. Conclusions: Biochemical thyroid function patterns at HT presentation in childhood and adolescence are mainly conditioned by patients’ age.