Screening for asymptomatic diabetes and metabolic comorbidities in pediatric patients during therapy for acute lymphoblastic leukemia.

OBJECTIVES: Chronic metabolic disturbances related to cancer treatment are well reported among survivors of pediatric acute lymphoblastic leukemia (ALL). However, few studies have investigated the incidence of these complications during the phase of chemotherapy. We evaluated the incidence of acute metabolic complications occurring during therapy in our cohort of patients diagnosed with ALL. METHODS: A prospective study involving 50 ALL pediatric patients diagnosed and treated between 2012 and 2016 in our oncology unit. We collected weight, blood pressure, fasting plasma glucose and hemoglobin A1C (HBA1c) levels during the two years of therapy. RESULTS: Obesity and overweight occurred in 43 and 25%, respectively among patients and have been reached at 12 months of chemotherapy. About 26% of the patients developed high blood pressure and 14% experienced hyperglycemias without meeting diabetes criteria. There was a significant decrease of HBA1c levels between the beginning and the end of therapy (p<0.0001). CONCLUSIONS: Increase of body mass index in our ALL pediatric patients occurred during the first months of therapy and plateaued after a year of treatment. We should target this population for early obesity prevention. HbA1c levels measured during therapy did not reveal diabetes criteria. Hence, fasting blood glucose levels are sufficient to monitor ALL pediatric patients' glycemia.

Long-Term Follow-up of Hypophosphatemic Bone Disease Associated With Elemental Formula Use: Sustained Correction of Bone Disease After Formula Change or Phosphate Supplementation.

In this article, we describe the long-term outcomes of children who were previously reported to have developed hypophosphatemic bone disease in association with elemental formula use. An extended chart review allowed for an updated report of 34 children with regard to severity/duration of bone disease, extent of recovery, and time to correction using radiology reports and biochemical data. After implementation of formula change and/or phosphate supplementation, we found that serum phosphorus concentration increased and serum alkaline phosphatase activity decreased in all patients, normalizing by 6.6 ± 4.0 (mean ± SD) months following diagnosis. The decrease in serum alkaline phosphatase from diagnosis to the time of correction was moderately correlated with the concurrent increase in serum phosphorus (R = 0.48, P < .05). Age at diagnosis significantly correlated with time to resolution (R = 0.51, P = .01). This study supports the earlier report that bone disease associated with hypophosphatemia during elemental formula use responds to formula change and/or phosphate supplementation.

Identifying pediatric diabetes cases from health administrative data: a population-based validation study in Quebec, Canada.

BACKGROUND: Type 1 diabetes is one of the most common chronic diseases in childhood with a worldwide incidence that is increasing by 3-5% per year. The incidence of type 2 diabetes, traditionally viewed as an adult disease, is increasing at alarming rates in children, paralleling the rise in childhood obesity. As the rates of diabetes increase in children, accurate population-based assessment of disease burden is important for those implementing strategies for health services delivery. Health administrative data are a powerful tool that can be used to track disease burden, health services use, and health outcomes. Case validation is essential in ensuring accurate disease identification using administrative databases. AIM: The aim of our study was to define and validate a pediatric diabetes case ascertainment algorithm (including any form of childhood-onset diabetes) using health administrative data. RESEARCH DESIGN AND METHODS: We conducted a two-stage method using linked health administrative data and data extracted from charts. In stage 1, we linked chart data from a large urban region to health administrative data and compared the diagnostic accuracy of various algorithms. We selected those that performed the best to be validated in stage 2. In stage 2, the most accurate algorithms were validated with chart data within two other geographic areas in the province of Quebec. RESULTS: Accurate identification of diabetes in children (ages ≤15 years) required four physician claims or one hospitalization (with International Classification of Disease codes within 1 year (sensitivity 91.2%, 95% confidence interval [CI] 89.2-92.9]; positive predictive value [PPV] 93.5%, 95% CI 91.7-95.0) or using only four physician claims in 2 years (sensitivity 90.4%, 95% CI 88.3-92.2; PPV 93.2%, 95% CI 91.7-95.0). Separating the physician claims by 30 days increased the PPV of all algorithms tested. CONCLUSION: Patients with child-onset diabetes can be accurately identified within health administrative databases providing a valid source of information for health care resource planning and evaluation.

Very Severe Resistance to Thyroid Hormone ß in One of Three Affected Members of a Family with a Novel Mutation in the THRB Gene.

A 13-year-old female with a novel THRB gene mutation (c.1033G>T, p.G345C) presented with 3- to 6-fold higher serum iodothyronine levels and more severe clinical manifestation than 2 other family members carrying the same mutation. The leukocytes of the proband expressed both wild-type and mutant THRB mRNAs, excluding the possibility of a partial deletion of the allele not carrying the mutation. The proband's fibroblasts showed reduced responsiveness to triiodothyronine compared with those of another affected family member. The more severe clinical and biochemical phenotype suggest a modifier-mediated worsening of the resistance to thyroid hormone.

Unexpected widespread hypophosphatemia and bone disease associated with elemental formula use in infants and children.

OBJECTIVE: Hypophosphatemia occurs with inadequate dietary intake, malabsorption, increased renal excretion, or shifts between intracellular and extracellular compartments. We noticed the common finding of amino-acid based elemental formula [EF] use in an unexpected number of cases of idiopathic hypophosphatemia occurring in infants and children evaluated for skeletal disease. We aimed to fully characterize the clinical profiles in these cases. METHODS: A retrospective chart review of children with unexplained hypophosphatemia was performed as cases accumulated from various centres in North America and Ireland. Data were analyzed to explore any relationships between feeding and biochemical or clinical features, effects of treatment, and to identify a potential mechanism. RESULTS: Fifty-one children were identified at 17 institutions with EF-associated hypophosphatemia. Most children had complex illnesses and had been solely fed Neocate® formula products for variable periods of time prior to presentation. Feeding methods varied. Hypophosphatemia was detected during evaluation of fractures or rickets. Increased alkaline phosphatase activity and appropriate renal conservation of phosphate were documented in nearly all cases. Skeletal radiographs demonstrated fractures, undermineralization, or rickets in 94% of the cases. Although the skeletal disease had often been attributed to underlying disease, most all improved with addition of supplemental phosphate or change to a different formula product. CONCLUSION: The observed biochemical profiles indicated a deficient dietary supply or severe malabsorption of phosphate, despite adequate formula composition. When transition to an alternate formula was possible, biochemical status improved shortly after introduction to the alternate formula, with eventual improvement of skeletal abnormalities. These observations strongly implicate that bioavailability of formula phosphorus may be impaired in certain clinical settings. The widespread nature of the findings lead us to strongly recommend careful monitoring of mineral metabolism in children fed EF. Transition to alternative formula use or implementation of phosphate supplementation should be performed cautiously with as severe hypocalcemia may develop.

The acetylome regulators Hdac1 and Hdac2 differently modulate intestinal epithelial cell dependent homeostatic responses in experimental colitis.

Histone deacetylases (Hdac) remove acetyl groups from proteins, influencing global and specific gene expression. Hdacs control inflammation, as shown by Hdac inhibitor-dependent protection from dextran sulfate sodium (DSS)-induced murine colitis. Although tissue-specific Hdac knockouts show redundant and specific functions, little is known of their intestinal epithelial cell (IEC) role. We have shown previously that dual Hdac1/Hdac2 IEC-specific loss disrupts cell proliferation and determination, with decreased secretory cell numbers and altered barrier function. We thus investigated how compound Hdac1/Hdac2 or Hdac2 IEC-specific deficiency alters the inflammatory response. Floxed Hdac1 and Hdac2 and villin-Cre mice were interbred. Compound Hdac1/Hdac2 IEC-deficient mice showed chronic basal inflammation, with increased basal disease activity index (DAI) and deregulated Reg gene colonic expression. DSS-treated dual Hdac1/Hdac2 IEC-deficient mice displayed increased DAI, histological score, intestinal permeability, and inflammatory gene expression. In contrast to double knockouts, Hdac2 IEC-specific loss did not affect IEC determination and growth, nor result in chronic inflammation. However, Hdac2 disruption protected against DSS colitis, as shown by decreased DAI, intestinal permeability and caspase-3 cleavage. Hdac2 IEC-specific deficient mice displayed increased expression of IEC gene subsets, such as colonic antimicrobial Reg3b and Reg3g mRNAs, and decreased expression of immune cell function-related genes. Our data show that Hdac1 and Hdac2 are essential IEC homeostasis regulators. IEC-specific Hdac1 and Hdac2 may act as epigenetic sensors and transmitters of environmental cues and regulate IEC-mediated mucosal homeostatic and inflammatory responses. Different levels of IEC Hdac activity may lead to positive or negative outcomes on intestinal homeostasis during inflammation.

The histone deacetylase Hdac1 regulates inflammatory signalling in intestinal epithelial cells.

BACKGROUND: It has recently been found that both nuclear epithelial-expressed histone deacetylases Hdac1 and Hdac2 are important to insure intestinal homeostasis and control the mucosal inflammatory response in vivo. In addition, HDAC inhibitors modulate epithelial cell inflammatory responses in cancer cells. However, little is known of the specific role of different HDAC, notably Hdac1, in the regulation of inflammatory gene expression in intestinal epithelial cells (IEC). METHODS: We investigated the role of Hdac1 in non-transformed IEC-6 rat cells infected with lentiviral vectors expressing specific Hdac1 shRNAs, to suppress Hdac1 expression. Proliferation was assessed by cell counting. Deacetylase activity was measured with a colorimetric HDAC assay. Cells were treated with IL-1ß and/or the JQ1 bromodomain acetyl-binding inhibitor. Nuclear protein levels of Hdac1, Hdac2, phosphorylated or unphosphorylated NF-κB p65 or C/EBPß, and NF-κB p50 and actin were determined by Western blot. Chemokine and acute phase protein expression was assessed by semi-quantitative RT-PCR analysis. Secreted cytokine and chemokine levels were assessed with a protein array. Chromatin immunoprecipitation experiments were done to assess RNA polymerase II recruitment. RESULTS: Reduced Hdac1 protein levels led to Hdac2 protein increases and decreased cell proliferation. Hdac1 depletion prolonged nuclear IL-1ß-induced phosphorylation of NF-κB p65 protein on Ser536 as opposed to total p65, and of C/EBPß on Ser105. In addition, semi-quantitative RT-PCR analysis revealed three patterns of expression caused by Hdac1 depletion, namely increased basal and IL-1ß-stimulated levels (Hp, Kng1), increased IL-1ß-stimulated levels (Cxcl2) and decreased basal levels with normal IL-1ß induction levels (Ccl2, Ccl5, Cxcl1, C3). Secreted cytokine and chemokine measurements confirmed that Hdac1 played roles both as an IL-1ß signalling repressor and activator. Hdac1 depletion did not alter the JQ1 dependent inhibition of basal and IL-1ß-induced inflammatory gene expression. Hdac1 depletion led to decreased basal levels of RNA polymerase II enrichment on the Ccl2 promoter, as opposed to the Gapdh promoter, correlating with decreased Ccl2 basal mRNA expression. CONCLUSIONS: Hdac1 is a major nuclear HDAC controlling IL-1ß-dependent inflammatory response in IEC, notably by regulating gene-specific transcriptional responses. Hdac1 may be important in restricting basal and inflammatory-induced gene levels to defined ranges of expression.

HDAC1 and HDAC2 restrain the intestinal inflammatory response by regulating intestinal epithelial cell differentiation.

Acetylation and deacetylation of histones and other proteins depends on histone acetyltransferases and histone deacetylases (HDACs) activities, leading to either positive or negative gene expression. HDAC inhibitors have uncovered a role for HDACs in proliferation, apoptosis and inflammation. However, little is known of the roles of specific HDACs in intestinal epithelial cells (IEC). We investigated the consequences of ablating both HDAC1 and HDAC2 in murine IECs. Floxed Hdac1 and Hdac2 homozygous mice were crossed with villin-Cre mice. Mice deficient in both IEC HDAC1 and HDAC2 weighed less and survived more than a year. Colon and small intestinal sections were stained with hematoxylin and eosin, or with Alcian blue and Periodic Acid Schiff for goblet cell identification. Tissue sections from mice injected with BrdU for 2 h, 14 h and 48 h were stained with anti-BrdU. To determine intestinal permeability, 4-kDa FITC-labeled dextran was given by gavage for 3 h. Microarray analysis was performed on total colon RNAs. Inflammatory and IEC-specific gene expression was assessed by Western blot or semi-quantitative RT-PCR and qPCR with respectively total colon protein and total colon RNAs. HDAC1 and HDAC2-deficient mice displayed: 1) increased migration and proliferation, with elevated cyclin D1 expression and phosphorylated S6 ribosomal protein, a downstream mTOR target; 2) tissue architecture defects with cell differentiation alterations, correlating with reduction of secretory Paneth and goblet cells in jejunum and goblet cells in colon, increased expression of enterocytic markers such as sucrase-isomaltase in the colon, increased expression of cleaved Notch1 and augmented intestinal permeability; 3) loss of tissue homeostasis, as evidenced by modifications of claudin 3 expression, caspase-3 cleavage and Stat3 phosphorylation; 4) chronic inflammation, as determined by inflammatory molecular expression signatures and altered inflammatory gene expression. Thus, epithelial HDAC1 and HDAC2 restrain the intestinal inflammatory response, by regulating intestinal epithelial cell proliferation and differentiation.

P2Y(2) receptor expression is regulated by C/EBPß during inflammation in intestinal epithelial cells.

Inflammatory bowel diseases are characterized by relapses and remission periods during which numerous factors, including stress factors and nucleotides, are mobilized to re-establish intestinal mucosal homeostasis. We have previously found that expression of the P2Y(2) nucleotide receptor is increased in colonic tissue isolated from inflammatory bowel disease patients as well as in a mouse model of colitis, and that P2Y(2) transcription is regulated in part by nuclear factor κB (NF-κB) p65. Transcription factor DNA-binding site analysis identified three potential CCAAT/enhancer-binding protein ß (C/EBPß) binding sites in the P2Y(2) proximal promoter. We then assessed the role of C/EBP transcription factors in the regulation of P2Y(2) in intestinal epithelial cells (IECs). We identified a region between -229 and -220 bp upstream of the transcription initiation site as a DNA-binding site for C/EBPß, by electrophoretic mobility and supershift assays. Mutagenesis of this site decreased C/EBPß-dependent P2Y(2) expression, as assessed by luciferase assays. In vivo, C/EBPß as well as P2Y(2) expression was increased in colonic IECs isolated from mice with dextran sulfate sodium-induced acute colitis. In contrast, P2Y(2) expression was decreased in C/EBPß-deficient mice treated with dextran sulfate sodium. Although C/EBPß was sufficient to induce P2Y(2) transcription, the effect of C/EBPß and NF-κB p65 on receptor transcription was synergistic. Chromatin immunoprecipitation assays revealed that both proteins simultaneously bind to the P2Y(2) promoter. Thus, we have identified C/EBPß as a novel regulator of P2Y(2) expression.

Prophylactic thyroidectomy in pediatric carriers of multiple endocrine neoplasia type 2A or familial medullary thyroid carcinoma: mutation in C620 is associated with Hirschsprung's disease.

PURPOSE: Prophylactic total thyroidectomy is now recommended after having confirmed RET mutations in children of parents with multiple endocrine neoplasia type 2 or familial medullary thyroid carcinoma. We reviewed our experience to determine the incidence of medullary thyroid carcinoma with respect to age at surgery, the location of the mutation, and its association with Hirschsprung's disease (HD). METHODS: A retrospective review from 1996 to 2005 revealed 20 children with genetic screening for multiple endocrine neoplasia type 2A or familial medullary thyroid carcinoma who underwent a prophylactic total thyroidectomy with parathyroid gland preservation. RESULTS: The median age of the 20 patients (9 boys and 11 girls) included in this study was 8.2 years (range, 3.7-16.9 years) at the time of their surgery. Final pathology revealed normal thyroid tissue (n = 3; median age, 5.9 years), C-cell hyperplasia (n = 13; median age, 10 years), or medullary thyroid carcinoma (n = 4; median age, 8 years). Four children, all with mutations in C620, had a previous diagnosis of HD. At a median follow-up of 3.7 years (range, 1 month to 8.4 years), all patients were well and cancer free. CONCLUSIONS: There is no correlation between histologic findings and median age at surgery. Hirschsprung's disease was found in 50% of the patients with the RET mutation in C620. In children of C620 parents, symptoms of HD should be actively sought, and if such are found, rectal biopsies should be performed even if mutation results are not yet available. Based on the age of the earliest cancer and the safety of total thyroidectomy, children should promptly undergo surgery after genetic screening and before their fifth year of life.