Methimazole associated neutropenia in a preterm neonate treated for hyperthyroidism.

Maternal Graves' disease is relatively uncommon with an estimated incidence of 0.4%-1% of all pregnancies, but only 1-5% of newborns delivered to mothers with Graves' disease develop overt clinical signs and symptoms of hyperthyroidism. Here, we describe a case of a 1380-gram female neonate who was born at 30-week gestation to a mother with Graves' disease. Our patient presented with hyperthyroidism followed by transient hypothyroidism requiring treatment with levothyroxine. While hyperthyroid, she was treated with methimazole, iodine, and a beta-blocker. 20 days after the initiation of methimazole, she developed neutropenia. The neutrophil counts started to improve immediately after the initiation of the weaning of methimazole. To the best of our knowledge, this is the first case reported in the literature of methimazole induced neutropenia in a preterm infant being treated for neonatal Graves' disease.

Effect of prolonged discontinuation of L-thyroxine replacement in a child with congenital hypothyroidism.

When diagnosed through neonatal screening and treated promptly and adequately, infants with congenital hypothyroidism (CH) experience normal physical growth and neurological development. Here we present a 3-year-old boy diagnosed with CH as a newborn, who was subsequently left untreated and experienced significant growth failure and developmental delay. This case emphasizes the importance of a consistent adherence to treatment in preventing such complications, especially in infancy and early childhood.

Long-term effects of a non-intensive weight program on body mass index and metabolic abnormalities of obese children and adolescents.

BACKGROUND: Previous studies have demonstrated positive effects of short-term, intensive weight-loss programs in obese children. OBJECTIVES: We evaluated the long-term effects of a non-intensive weight management program on the BMI, glycemic measures and lipid profiles of obese youth. METHODS: Retrospective chart review of 61 obese children followed at our Weight Management Center. During visits, dietary changes and regular physical activity were recommended. Anthropometric and laboratory parameters were evaluated. RESULTS: At the initial visit, the mean age was 11.1 ± 2.6 years. The follow-up period was 47.3 ± 11.1 months; the number of outpatient visits per year (OV/yr) was 2.9 ± 0.9. At the end of the follow-up, the whole group exhibited decreased BMI z-score and LDL-cholesterol when compared to the initial visit. In the subset of subjects in whom OGTT was performed, 2-hour glucose and peak insulin were decreased. Compared to children with ≤ 2 OV/year, those with > 2 OV/year (3.19 ± 0.7) exhibited a significant decrease in their BMI z-score, LDL-cholesterol, 2-hour glucose, and peak insulin. CONCLUSIONS: Our study suggests that a periodical (~ 3 OV/yr) evaluation in a non-intensive, long-term weight management program may significantly improve the degree of obesity and cardiovascular risk factors in childhood.

Role of fibroblast growth factor 21 (FGF21) in undernutrition-related attenuation of growth in mice.

Reduced caloric intake in mammals causes reduced skeletal growth and GH insensitivity. However, the underlying molecular mechanisms are not fully elucidated. The aim of this study was to determine whether the increased activity of fibroblast growth factor 21 (FGF21) during chronic undernutrition in mice causes GH insensitivity and growth failure. After 4 wk of food restriction, fgf21 knockout (KO) mice exhibited greater body and tibial growth than their wild-type (WT) littermates. Daily injections of recombinant human FGF21 in a subgroup of food-restricted fgf21 KO mice prevented these differences in body and tibial growth. At the end of the 4-wk food restriction, GH binding and GH receptor expression were reduced in the liver and in the growth plate of food-restricted WT mice (compared to WT mice fed ad libitum), whereas they were similar between food-restricted and ad libitum KO mice. In addition, a single injection of GH induced greater liver signal transducer and activator of transcription 5 phosphorylation and IGF-I mRNA in food-restricted KO mice than in WT mice. Lastly, in the tibial growth plate of food-restricted WT mice, FGF21 mRNA and protein expression was greater than that of WT mice fed ad libitum. In contrast, the IGF-I mRNA and protein expression was smaller. Our findings support a causative role for FGF21 in the inhibition of skeletal growth during prolonged undernutrition. Such role may be mediated by the antagonistic effect of FGF21 on GH action in the liver and, possibly, in the growth plate.

An adolescent with a mediastinal mass, diagnosed with Graves disease and thymic hyperplasia.

Graves disease is an autoimmune disorder characterized by thyroid enlargement and hyperthyroidism. Thyrotropin receptor (TSHR) autoantibodies bind the TSHR on the membrane of thyroid follicular cells and stimulate cell proliferation and thyroid-hormone synthesis. TSHR has also been identified in extrathyroidal organs, including the human thymus. Thus far, radiologically detectable thymic enlargement has only been reported in adults with Graves disease. We present here the case of a child with Graves disease and significant thymic hyperplasia. L. K. was a 15-year-old girl evaluated for cough and dyspnea on exertion. A chest radiograph was obtained, and it revealed a widened superior mediastinum. A computed-tomography scan of her chest identified a mass in the anterior mediastinum without associated lymphadenopathy. Because of these radiologic findings and her weight loss, she was referred to the oncology service; a biopsy of the mediastinal mass was obtained and revealed thymic reactive hyperplasia. Because of persistent tachycardia, thyroid studies were obtained, and the diagnosis of Graves disease was established. The child's physical examination revealed a minimally enlarged thyroid gland and no exophthalmos. One month after medical treatment was initiated, a repeat computed-tomography scan of her chest identified significantly reduced thymic size. To our knowledge, this is the first pediatric patient reported with Graves disease and significant thymic enlargement. Considering the diagnosis of Graves disease for a child with an anterior mediastinal mass and without the typical physical findings of autoimmune hyperthyroidism (goiter, exophthalmos) may prevent unnecessary diagnostic studies and their associated financial and emotional costs.